Interventions for treating cavitated or dentine carious lesions

BACKGROUND

Traditionally, cavitated carious lesions and those extending into dentine have been treated by 'complete' removal of carious tissue, i.e. non-selective removal and conventional restoration (CR). Alternative strategies for managing cavitated or dentine carious lesions remove less or none of the carious tissue and include selective carious tissue removal (or selective excavation (SE)), stepwise carious tissue removal (SW), sealing carious lesions using sealant materials, sealing using preformed metal crowns (Hall Technique, HT), and non-restorative cavity control (NRCC).

OBJECTIVES

To determine the comparative effectiveness of interventions (CR, SE, SW, sealing of carious lesions using sealant materials or preformed metal crowns (HT), or NRCC) to treat carious lesions conventionally considered to require restorations (cavitated or micro-cavitated lesions, or occlusal lesions that are clinically non-cavitated but clinically/radiographically extend into dentine) in primary or permanent teeth with vital (sensitive) pulps.

SEARCH METHODS

An information specialist searched four bibliographic databases to 21 July 2020 and used additional search methods to identify published, unpublished and ongoing studies.  SELECTION CRITERIA: We included randomised clinical trials comparing different levels of carious tissue removal, as listed above, against each other, placebo, or no treatment. Participants had permanent or primary teeth (or both), and vital pulps (i.e. no irreversible pulpitis/pulp necrosis), and carious lesions conventionally considered to need a restoration (i.e. cavitated lesions, or non- or micro-cavitated lesions radiographically extending into dentine). The primary outcome was failure, a composite measure of pulp exposure, endodontic therapy, tooth extraction, and restorative complications (including resealing of sealed lesions).

DATA COLLECTION AND ANALYSIS

Pairs of review authors independently screened search results, extracted data, and assessed the risk of bias in the studies and the overall certainty of the evidence using GRADE criteria. We measured treatment effects through analysing dichotomous outcomes (presence/absence of complications) and expressing them as odds ratios (OR) with 95% confidence intervals (CI). For failure in the subgroup of deep lesions, we used network meta-analysis to assess and rank the relative effectiveness of different interventions.

MAIN RESULTS

We included 27 studies with 3350 participants and 4195 teeth/lesions, which were conducted in 11 countries and published between 1977 and 2020. Twenty-four studies used a parallel-group design and three were split-mouth. Two studies included adults only, 20 included children/adolescents only and five included both. Ten studies evaluated permanent teeth, 16 evaluated primary teeth and one evaluated both. Three studies treated non-cavitated lesions; 12 treated cavitated, deep lesions, and 12 treated cavitated but not deep lesions or lesions of varying depth.  Seventeen studies compared conventional treatment (CR) with a less invasive treatment: SE (8), SW (4), two HT (2), sealing with sealant materials (4) and NRCC (1). Other comparisons were: SE versus HT (2); SE versus SW (4); SE versus sealing  with sealant materials (2); sealant materials versus no sealing (2).  Follow-up times varied from no follow-up (pulp exposure during treatment) to 120 months, the most common being 12 to 24 months. All studies were at overall high risk of bias. Effect of interventions Sealing using sealants versus other interventions for non-cavitated or cavitated but not deep lesions There was insufficient evidence of a difference between sealing with sealants and CR (OR 5.00, 95% CI 0.51 to 49.27; 1 study, 41 teeth, permanent teeth, cavitated), sealing versus SE (OR 3.11, 95% CI 0.11 to 85.52; 2 studies, 82 primary teeth, cavitated) or sealing versus no treatment (OR 0.05, 95% CI 0.00 to 2.71; 2 studies, 103 permanent teeth, non-cavitated), but we assessed all as very low-certainty evidence. HT, CR, SE, NRCC for cavitated, but not deep lesions in primary teeth The odds of failure may be higher for CR than HT (OR 8.35, 95% CI 3.73 to 18.68; 2 studies, 249 teeth; low-certainty evidence) and lower for HT than NRCC (OR 0.19, 95% CI 0.05 to 0.74; 1 study, 84 teeth, very low-certainty evidence). There was insufficient evidence of a difference between SE versus HT (OR 8.94, 95% CI 0.57 to 139.67; 2 studies, 586 teeth) or CR versus NRCC (OR 1.16, 95% CI 0.50 to 2.71; 1 study, 102 teeth), both very low-certainty evidence. CR, SE, SW for deep lesions The odds of failure were higher for CR than SW in permanent teeth (OR 2.06, 95% CI 1.34 to 3.17; 3 studies, 398 teeth; moderate-certainty evidence), but not primary teeth (OR 2.43, 95% CI 0.65 to 9.12; 1 study, 63 teeth; very low-certainty evidence). The odds of failure may be higher for CR than SE in permanent teeth (OR 11.32, 95% CI 1.97 to 65.02; 2 studies, 179 teeth) and primary teeth (OR 4.43, 95% CI 1.04 to 18.77; 4 studies, 265 teeth), both very low-certainty evidence. Notably, two studies compared CR versus SE in cavitated, but not deep lesions, with insufficient evidence of a difference in outcome (OR 0.62, 95% CI 0.21 to 1.88; 204 teeth; very low-certainty evidence). The odds of failure were higher for SW than SE in permanent teeth (OR 2.25, 95% CI 1.33 to 3.82; 3 studies, 371 teeth; moderate-certainty evidence), but not primary teeth (OR 2.05, 95% CI 0.49 to 8.62; 2 studies, 126 teeth; very low-certainty evidence). For deep lesions, a network meta-analysis showed the probability of failure to be greatest for CR compared with SE, SW and HT.

AUTHORS' CONCLUSIONS

Compared with CR, there were lower numbers of failures with HT and SE in the primary dentition, and with SE and SW in the permanent dentition. Most studies showed high risk of bias and limited precision of estimates due to small sample size and typically limited numbers of failures, resulting in assessments of low or very low certainty of evidence for most comparisons.

Maxillary Implant-Supported Overdentures: Mechanical Behavior Comparing Individual Axial and Bar Retention Systems. A Cohort Study of Edentulous Patients

Background and objectives: To compare the medium- to long-term mechanical behavior of overdentures with two different retention systems: overdentures with Locator® axial retention, and vertical insertion overdentures with bar retention, used to rehabilitate edentulous maxillar. Material and Methods: This prospective study assessed patients presenting complete maxillary edentulism, rehabilitated by means of implant-supported overdentures (n = 20), 10 with Locator® axial retention (ODA group) and 10 with overdentures on bars (ODB group). Patients also completed a questionnaire to determine their satisfaction with treatment. Results: The mean follow-up time in both groups was 11.4 years, with follow-up times in both groups ranging from 5 to 14 years. The ODA group suffered mechanical complications such as retention loss, need for nylon retention insert changes, resin fracture, and need for relining. In the ODB group, prosthetic dental wear, screw loosening, and complete prosthetic failure were more common. A total of 19 implants failed (23.8%); of these, 11 were in the ODA group (failure rate = 27.5%) and eight in the ODB group (failure rate = 20%). The patient satisfaction questionnaire obtained a mean score of 7.9 out of 10 in the ODA group, and 9.75 in the ODB group. Conclusions: in rehabilitations of edentulous maxillar by means of implant-supported overdentures, both the systems assessed were shown to be effective in the medium to long term. Patients expressed a high level of satisfaction with the treatments received.

Dental cavity liners for Class I and Class II resin-based composite restorations

BACKGROUND

Resin-based composite (RBC) is currently accepted as a viable material for the restoration of caries for posterior permanent teeth requiring surgical treatment. Despite the fact that the thermal conductivity of the RBC restorative material closely approximates that of natural tooth structure, postoperative hypersensitivity is sometimes still an issue. Dental cavity liners have historically been used to protect the pulp from the toxic effects of some dental restorative materials and to prevent the pain of thermal conductivity by placing an insulating layer between restorative material and the remaining tooth structure. This is an update of the Cochrane Review first published in 2016.

OBJECTIVES

The objective of this review was to assess the effects of using dental cavity liners in the placement of Class I and Class II resin-based composite posterior restorations in permanent teeth in children and adults.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 12 November 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10) in the Cochrane Library (searched 12 November 2018), MEDLINE Ovid (1946 to 12 November 2018), Embase Ovid (1980 to 12 November 2018) and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 12 November 2018). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomized controlled trials assessing the effects of the use of liners under Class I and Class II posterior resin-based composite restorations in permanent teeth (in both adults and children). We included both parallel and split-mouth designs.

DATA COLLECTION AND ANALYSIS

We utilized standard methodological procedures prescribed by Cochrane for data collection and analysis. Two review authors screened the search results and assessed the eligibility of studies for inclusion against the review inclusion criteria. We conducted risk of bias assessments and data extraction independently and in duplicate. Where information was unclear we contacted study authors for clarification.

MAIN RESULTS

Eight studies, recruiting over 700 participants, compared the use of dental cavity liners to no liners for Class I and Class II resin-based composite restorations.Seven studies evaluated postoperative hypersensitivity measured by various methods. All studies were at unclear or high risk of bias. There was inconsistent evidence regarding postoperative hypersensitivity (either measured using cold response or patient-reported), with a benefit shown at some, but not all, time points (low-quality evidence).Four trials measured restoration longevity. Two of the studies were judged to be at high risk and two at unclear risk of bias. No difference in restoration failure rates were shown at 1 year follow-up, with no failures reported in either group for three of the four studies; the fourth study had a risk ratio (RR) 1.00 (95% confidence interval (CI) 0.07 to 15.00) (low-quality evidence). Three studies evaluated restoration longevity at 2 years follow-up and, again, no failures were shown in either group.No adverse events were reported in any of the included studies.

AUTHORS' CONCLUSIONS

There is inconsistent, low-quality evidence regarding the difference in postoperative hypersensitivity subsequent to placing a dental cavity liner under Class I and Class II posterior resin-based composite restorations in permanent posterior teeth in adults or children 15 years or older. Furthermore, no evidence was found to demonstrate a difference in the longevity of restorations placed with or without dental cavity liners.

Comparative study of immediate loading on short dental implants and conventional dental implants in the posterior mandible: A randomized clinical trial

PURPOSE

Immediate dental implant loading has been investigated with favorable results. However, short implants have not been investigated in this treatment option. This study compared the clinical outcomes and survival rates of immediately loaded short and conventional length dental implants in replacing mandibular molar teeth.

MATERIALS AND METHODS

Forty-six implants (23 short dental implants and 23 conventional dental implants) in 46 patients were included in the study. Provisional computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic crowns were cemented to the abutments and immediately loaded. Several clinical parameters were recorded and statistically analyzed at 4-month- and 1-year-follow-up.

RESULTS

Two short implants lost integration, and one conventional implant failed. No statistically significant difference between the two implant types was found (P = 1.00). Minor complications were recorded; three provisional crown fractures were found in the short implant group and two provisional crown fractures in the conventional implant group. There was no significant difference in implant stability quotient values for short or conventional implants between baseline (short: 73.86 ± 2.38, conventional: 75.05 ± 3.26, P = .088), 4 months after loading (short: 72.37 ± 1.35, conventional: 72.89 ± 1.87, P = .165), and 1 year after loading (short: 74.60 ± 2.03, conventional: 75.35 ± 2.66, P = .296). The mean marginal bone level loss 4 months after loading was 0.28 ± 0.29 mm for short implants and 0.25 ± 0.25 mm for conventional implants (P = .73), and at 1 year after loading was 0.33 ± 0.47 mm for short implants and 0.26 ± 0.27 mm for conventional implants (P = .554); there was no statistical difference between the two implant types.

CONCLUSION

The immediate loading of short implants is comparable to conventional length implants in terms of implant survival, marginal bone level change, and implant stability quotient value.

Clinical Outcomes of Monolithic Zirconia Crowns with CAD/CAM Technology. A 1-Year Follow-Up Prospective Clinical Study of 65 Patients

Aim/Purpose: The primary aim of this study was to examine the clinical performance of posterior monolithic single crowns in terms of failure or complications and the secondary aim was to assess the quality of these restorations according to the United States Public Health Service (USPHS) criteria. Methods: Ιn a private dental clinic, 65 patients with need of posterior crowns were restored with monolithic zirconia crowns. All the restorations were evaluated 6 and 12 months after their cementation. The modified United States Public Health Service (USPHS) criteria and periodontal parameters were applied for the clinical evaluation of the crowns. Restorations with Alpha or Bravo rating were considered a success. Results: Descriptive statistics and nonparametric tests were used for statistical analysis. Sixty-five patients (mean age: 49.52) were restored with 65 monolithic zirconia crowns. No fracture of the restorations was recorded. The overall success rate was 98.5%. The clinical quality of all crowns was acceptable except for the marginal discoloration of one crown at the 6- and 12-month follow-up examination. Conclusions: In this study, no fracture of single-tooth monolithic crowns occurred and the success rate was high. Monolithic zirconia restorations fabricated is a viable option for the restoration of single posterior teeth.

Analysis of the causes of dental implant fracture: A retrospective clinical study

OBJECTIVE

Fracture of osseointegrated dental implants is the most severe mechanical complication. The aim of the present study was to analyze possible causative factors for implant body fracture.

METHOD AND MATERIALS

One hundred and one patients with 218 fitted implants and a follow-up period of 3 to 10 years were studied. Factors associated with biomechanical and physiologic overloading such as parafunctional activity (eg, bruxism), occlusion, and cantilevers, and factors related to the planning of the dental prosthesis, available bone volume, implant area, implant diameter, number of implants, and their inclination were tracked. The impact of their effect was analyzed using the Bonferroni-corrected post-hoc Mann-Whitney test for each group.

RESULTS

The incidence of dental implant fracture was 2.3% in the investigated cases. Improper treatment planning, bruxism, and time of the complication setting in were the main factors leading to this complication. Typical size effect was established only for available bruxism, occlusal errors, and their activity duration. These complications were observed most often with single crown prostheses, and in combination with parafunctional activities such as bruxism and lack of implant-protected occlusion.

CONCLUSION

Occlusal overload due to bruxism or inappropriate or inadequate occlusion as a single factor or a combination of these factors during the first years after the functional load can cause implant fracture. Fracture of the implant body more frequently occurred with single crowns than with other implant-supported fixed dental prostheses.

Does the Presence of a Cantilever Influence the Survival and Success of Partial Implant-Supported Dental Prostheses? Systematic Review and Meta-Analysis

PURPOSE

To investigate if the presence of a cantilever influences the survival and success of partial fixed implant-supported prostheses, through a systematic review and meta-analysis, with additional analysis of the survival and marginal bone loss rates and prosthesis complications.

MATERIALS AND METHODS

The register protocol of the review in the PROSPERO database is CRD42016052008. The MEDLINE and Scopus databases were used for an electronic search of relevant studies up to November 2016, by means of two independent reviewers. The keywords included the combinations "fixed partial denture" with "dental implants", and with "extension" or "cantilever"; and "implant-supported dental prosthesis" with "extension" or "cantilever". The inclusion criteria were randomized clinical trials and prospective and retrospective clinical studies in English that addressed the comparison of success and survival of the use of implant-supported fixed prostheses, with and without cantilevers. Data from the selected studies were used to perform the statistical analysis.

RESULTS

Among the 408 articles identified, 4 articles met the eligibility criteria. The presence of a cantilever did not compromise marginal bone loss or the survival of the prostheses. However, minor complications were encountered for the group of partial fixed prostheses without cantilevers, with a statistical difference (P = .008).

CONCLUSION

Cantilevers can be used in fixed prostheses and do not interfere negatively in the survival or success of the prosthesis or the marginal bone loss. However, there are minor complications when prostheses without cantilevers, or short cantilevers, are used.

Comparative Clinical Evaluation of Composite Overcast Gold Post and Core Buildups in Endodontically Treated Teeth

BACKGROUND

The management of non-vital teeth includes endodontic treatment and restoration followed by post and core restoration in selected cases. The present study was conducted to compare the indirect cast post, and core buildup with direct composite post build up in patients.

MATERIALS AND METHODS

The present study was conducted on 128 teeth of 82 patients. The success rate over 3 years was evaluated clinically and radiographically by observing caries, tooth mobility, probing depth, periapical pathology, and root fractures.

RESULTS

Group I consisted of 16 incisors, 20 canines, 22 premolars, and six molars while group II had 17 incisors, 14 canines, 25 premolars, and eight molars. The difference was statistical non-significant (p-0.1). Forty-four teeth in group I and 42 teeth in group II utilized composite cement, whereas 18 teeth in group I and 16 teeth in group II used GIC and zinc phosphate was used in two teeth in group I and six teeth in group II. The difference was statistical ly significant (p< 0.05). Four teeth in group I and 8 in group II were lost. One tooth in group I and two teeth in group II showed root fracture and three teeth in group I and six teeth in group II showed periapical pathology. The difference was statistically significant (p-0.01). Most common type of complication was probing depth > 4 mm, caries, tooth mobility, and root fracture. The difference was non- significant (p-0.31).

CONCLUSION

Both composite post buildup and cast gold post and core build-up exhibited similar properties.

CLINICAL SIGNIFICANCE

Both composite post buildup and cast gold post and core build-up exhibited similar properties hence either of the methods can be used in post core build up.

Microtensile Bond Strength Between Glass Ionomer Cement and Silver Diamine Fluoride-Treated Carious Primary Dentin

Purpose: The study objectives were to investigate the effect of silver diamine fluoride (SDF) on the microtensile bond strength between glass ionomer cement and carious primary dentin and evaluate the mode of restoration failure. Methods: Forty carious primary molars were sectioned in half through the middle of the carious lesion and randomly allocated to test and control groups. The test specimens were treated with 38 percent SDF, and the control, deionized water. The samples were stored in artificial saliva for 14 days at 37 degrees Celsius, and the dentin surfaces were conditioned and restored with Fuji IX GP Extra. After 24 hours in artificial saliva, the specimens were prepared for microtensile bond strength testing and stressed in tension at one mm per minute until failure. Mean bond strengths were compared using the paired t test. The failure mode was assessed with a stereomicroscope under 40X magnification. Results: The mean microtensile strength for the test group was 7.4 MPa (SD=±5.1) and 6.3 (±4.6) for the control group (P>0.05). Most common failure mode was the mixed failure mode in both groups. Conclusion: Silver diamine fluoride does not adversely affect the bond strength between glass ionomer cement and carious primary dentin in vitro.

Prognostic Implication of Selective Serotonin Reuptake Inhibitors in Osseointegration of Dental Implants: A 5-year Retrospective Study

AIM

Dental implants are the preferred treatment modality in the present edentulous era. Selective serotonin reuptake inhibitors (SSRIs) have detrimental effect on bone density. The present study was conducted to determine the effect of SSRIs on the success rate of dental implants.

MATERIALS AND METHODS

The present study was conducted on 352 patients of both genders with 680 dental implants. History of depression and SSRI medication was retrieved. Patients were divided into two groups. Group I (110 patients, 230 dental implants) patients were on SSRI, while group II (242 patients, 450 dental implants) patients were non-SSRI. In all patients, the implant failure rate was recorded.

RESULTS

In group I, 35 patients were >50 years, while 75 were <50 years of age. In group II, 60 patients were >50 years, while 182 were <50 years of age. The difference was significant (p < 0.05). Group I had 45 males and 65 females, while group II comprised of 105 males and 137 females. Group I showed 25 implant failures and group II had 21 implant failures. Age group >50 years showed 12 implant failures while <50 years had 13 in group I compared with 10 in patients >50 years and 11 in patients with <50 years of age; 56% smokers had implant in group I as compared with 60% failure in group II. In group I, 27% diabetic patients had failures as compared with 13.4% in group II. The difference was significant (p < 0.05). Group I showed maximum failures in terms of loosening of screw (8) followed by fracture of implant (7), peri-implantitis (6), and fracture of screw (4), whereas in group II, 7 cases were of loosening of screw, 6 cases were of fracture of screw, 5 cases of fracture of implant, and 3 cases of peri-implantitis. The difference was nonsignificant (p > 0.05).

CONCLUSION

Selective serotonin reuptake inhibitors cause increased osteoclastic activity, leading to bone loss and implants placed in patients with history of depression are more prone to failures.

CLINICAL SIGNIFICANCE

Failure rates of dental implants are significantly increased in patients taking SSRIs due to depression. Careful case analysis and history of depression may minimize the failure rates.

Retrospective Analysis of Long-Term (up to 12 years) Clinical and Radiologic Performance of Anodized-Surface Implants

To accurately assess the long-term performance of anodized-surface implants, more data monitoring is needed outside of clinical evaluations. This retrospective study evaluated long-term implant survival and bone remodeling after up to 12 years of function. Data from 195 implants placed in 60 patients over a follow-up period ranging from 0.6 to 12.1 years were included. The implant-level survival rate was 99.0%. Marginal bone loss remained low across all follow-up cohorts. The data show that anodized-surface implants are a safe, reliable option with high implant survival rates and low levels of bone loss.

Immediately Loaded, Implant-Supported Overdentures Retained by a Milled Bar: An Up-to-5-Year Retrospective Clinical Study

This study was conducted as an up-to-5-year retrospective investigation estimating survival rate, marginal bone loss (MBL), patient satisfaction, complications, and required prosthodontic maintenance for immediately loaded, milled bar-retained, implant-supported overdentures (ISOs). A total of 60 patients, 69 overdentures, and 179 implants were examined. The implant survival rate was 96.65%, and the mean MBL was 0.57 mm (SD 0.52). High subjective satisfaction ratings, ranging from 3 to 5 with a mean of 4.3 (SD 0.6), were observed. The incidence of complications and prosthetic maintenance was low and required short standard appointments. The present findings encourage the use of immediately loaded, milled bar-retained ISOs.

The longevity of posterior restorations in primary teeth

Data sourcesSciVerse Scopus, ISIS Web of Science, Cochrane library, Medline/PubMed. Studies published from 1996 to 2017 in English were considered.Study selectionTwo independent reviewers screened the literature. Randomised clinical trials, non-randomised clinical trials with parallel groups or single group, retrospective studies) evaluating different posterior restorations (class I, class II restorations and crowns) with different materials (amalgam, compomer, composite, glass ionomer cement, stainless steel crown) placed in primary teeth by reporting different outcomes measures (survival rate, success rate, annual failure rate).Data extraction and synthesisTwo independent reviewers extracted data. Risk of bias was assessed using the Cochrane tool. A qualitative analysis was conducted.ResultsThirty-one studies were included. Seven different materials were used for restorations: amalgam (six studies), compomer (nine studies), composite (six studies), conventional glass ionomer cement (five studies), metal-reinforced glass ionomer cement (MRGIC) (four studies), resin-modified glass ionomer cement (ten studies), and stainless steel crown (SSC) (three studies). When considering the annual failure rate (AFR), composite showed the lowest (1.7-12.9%) and MRGIC showed the highest (10.0-29.9%). For the success rate, SSC presented the highest (96.1%) and MRGIC presented the lowest (57.4%). Class I restorations and restorations placed under the use of rubber dam revealed better results in both AFR and success rate. The main reason for failure was secondary caries.ConclusionsThere is a large variation in longevity of posterior restorations in primary teeth. Secondary caries is the main reason causing failure.

Success and Failure Rates of 1,344 6- to 9-mm-Length Rough-Surface Implants Placed at the Time of Transalveolar Sinus Elevations, Restored with Single Crowns, and Followed for 60 to 229 Months in Function

PURPOSE

To assess the success and stability of 6-, 7-, 8-, and 9-mm-long, 6.5-mm-wide-neck tissue-level implants placed at the time of transalveolar sinus augmentation therapy, utilizing a trephine and osteotome approach, which were restored with single crowns.

MATERIALS AND METHODS

In total, 1,344 implants were placed by the author, varying in length from 6 to 9 mm, with parallel-wall 4.8-mm-diameter implant bodies and 6.5-mm-diameter implant necks. The implants were restored with single abutments and crowns by a variety of practitioners. They were followed for 60 to 229 months in function, with a mean time of 121.1 months in function. Implant success was evaluated by the author utilizing a combination of the Albrektsson et al criteria, and buccal and palatal/lingual bone sounding under anesthesia.

RESULTS

The overall cumulative success rate was 98.8%. One hundred ninety 6-mm-long implants demonstrated a cumulative success rate of 97.5% at a mean time of 109.2 months in function. Eleven 7-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 218.5 months in function. One thousand ninety-four 8-mm-long implants demonstrated a cumulative success rate of 98.9% at a mean time of 112.3 months in function. Forty-nine 9-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 212.1 months in function.

CONCLUSION

Implants of 6 to 9 mm in length, placed at the time of trephine and osteotome transalveolar sinus elevation procedures and restored with abutments and single crowns, demonstrate a high level of long-term clinical success, assuming specific comprehensive treatment criteria are met.

Two Bilateral Zygomatic Implants Placed and Immediately Loaded: A Retrospective Chart Review with Up-to-54-Month Follow-up

PURPOSE

To report on the outcome of placement of two bilateral zygomatic implants with an immediately loaded prosthesis.

MATERIALS AND METHODS

A retrospective chart review was conducted of all patients treated with zygomatic implants between August 1, 2011 and June 6, 2016. All patients had at least two zygomatic implants placed bilaterally and immediately loaded with a provisional prosthesis the same day of implant placement. The implants were Nobel Biocare TiUnite or machined surface with lengths of 30 to 52.5 mm. All patients were treated by a team consisting of one surgeon, a restorative dentist or prosthodontist, an anesthesiologist, and a laboratory technician. Implant success was defined as successful integration of the implant; prosthetic success was defined as retention of the prosthesis under normal function.

RESULTS

One hundred five zygomatic implants were placed and immediately loaded in 28 patients over a period of 1 to 60 months. Ages ranged from 46 to 81 years, with 26 female and 2 male patients. All the implants were placed by one surgeon. The immediate load on the day of implant placement was completed by either one of 2 prosthodontists or 11 restorative dentists. Implant success was 96% (101/105). All four failed implants were in one patient and were TiUnite surface coated.

CONCLUSION

This study demonstrated that two zygomatic implants bilaterally placed and immediately loaded with a full-arch splinted prosthesis will provide a predictable outcome.

Effect of Abutment Preparation and Fatigue Loading in a Moist Environment on the Fracture Resistance of the One-Piece Zirconia Dental Implant

PURPOSE

One-piece zirconia dental implants have been widely used in Europe for many years. This in vitro study was done to evaluate the effect of abutment preparation and fatigue (cyclic) loading in a moist environment on the fracture resistance of the one-piece zirconia dental implant.

MATERIALS AND METHODS

Twenty-four Cera Root zirconium oxide dental implants, divided into three groups of eight, were used in this study: group 1 (control group): implants with no preparation, tested in a dry environment; group 2: implants with no preparation, tested in a moist environment (simulating clinical conditions); and group 3: implants after abutment preparation tested in a moist environment. All implants received IPS e.max porcelain crowns. All samples were subjected to nearly 1 million cycles of sinusoidal fatigue loading (-10 N to -200 N) in a universal testing machine. The postfatigue samples were loaded to fracture. Significant differences (α = .05) in mean fracture loads were statistically analyzed.

RESULTS

There was no catastrophic failure of any of the implants during the fatigue tests. The mean (SD) of the fracture loads in postfatigue load-to-failure tests were: group 1: 1,202.9 (62.6); group 2: 1,164.6 (73.8); and group 3: 953.5 (103). Analysis of variance (ANOVA) and post hoc Tukey-Kramer contrast revealed a statistically significant difference (P < .05) between the mean fracture load of group 3 and those of groups 1 and 2, but no significant difference (P > .05) between groups 1 and 2.

CONCLUSION

While there was a statistically significant adverse effect of abutment preparation and fatigue loading in a moist environment on the postfatigue implant failure load, the load-to-fracture mean of surface-prepared implants after fatigue tests was nevertheless significantly higher than the mean fracture load of the crowns (P < .05) as well as the minimum load-bearing requirement (300 N) for anterior restorations. Abutment preparation in a one-piece zirconia implant is therefore considered clinically safe and acceptable.

Retrospective evaluation of posterior composite resin sandwich restorations with Herculite XRV: 18-year findings

OBJECTIVE

The aim of this retrospective study was to evaluate the long-term clinical outcomes of posterior composite resin sandwich restorations, and secondarily to assess the influence of potential factors on survival and causes of failure.

METHOD AND MATERIALS

Two hundred and four posterior Herculite XRV restorations due to primary caries performed between 1991 and 1997 were included. The restorations were assessed after 18 years, by two calibrated examiners, according to USPHS criteria. The survival of the restorations was estimated by the Kaplan-Meier estimator. Cox regression was applied to evaluate the influence of the cavity size, location of the tooth, caries risk, and gender on survival rate. The predictive power of the analyzed variables on survival rate was studied with multiple linear regression analysis.

RESULTS

After 10 years the survival rate was 92.6%, and 82.4% at the end of the study. Thirty-six (17.6%) restorations failed during the evaluation period, 21 (10.3%) of them after more than 10 years. The most common failure was secondary caries (69.4% of the failures). There were statistically significant differences in survival rate depending on caries risk (P = .000), but not between Class I and II (P = .106), and the type and localization of the tooth (P = .115).

CONCLUSION

Posterior Herculite XRV restorations due to primary caries have high long-term survival rates. Generally, failures occur by secondary caries and are more common in molars. The patient's caries risk is the variable that best predicts the survival of posterior restorations.

Atraumatic restorative treatment versus conventional restorative treatment for managing dental caries

BACKGROUND

Dental caries is a sugar-dependent disease that damages tooth structure and, due to loss of mineral components, may eventually lead to cavitation. Dental caries is the most prevalent disease worldwide and is considered the most important burden of oral health. Conventional treatment methods (drill and fill) involve the use of rotary burs under local anaesthesia. The need for an electricity supply, expensive handpieces and highly trained dental health personnel may limit access to dental treatment, especially in underdeveloped regions.To overcome the limitations of conventional restorative treatment, the Atraumatic Restorative Treatment (ART) was developed, mainly for treating caries in children living in under-served areas of the world where resources and facilities such as electricity and trained manpower are limited. ART is a minimally invasive approach which involves removal of decayed tissue using hand instruments alone, usually without use of anaesthesia and electrically driven equipment, and restoration of the dental cavity with an adhesive material (glass ionomer cement (GIC), composite resins, resin-modified glass-ionomer cement (RM-GICs) and compomers).

OBJECTIVES

To assess the effects of Atraumatic Restorative Treatment (ART) compared with conventional treatment for managing dental caries lesions in the primary and permanent teeth of children and adults.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 22 February 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 1), MEDLINE Ovid (1946 to 22 February 2017), Embase Ovid (1980 to 22 February 2017), LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 22 February 2017) and BBO BIREME Virtual Health Library (Bibliografia Brasileira de Odontologia; 1986 to 22 February 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with at least six months' follow-up that compared the effects of ART with a conventional restorative approach using the same or different restorative dental materials to treat caries lesions.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results, extracted data from included studies and assessed the risk of bias in those studies. We used standard methodological procedures expected by Cochrane to evaluate risk of bias and synthesise data. Where pooling was appropriate we conducted meta-analyses using the random-effects model. We assessed the quality of the evidence using GRADE criteria.

MAIN RESULTS

We included a total of 15 eligible studies randomising 3760 participants in this review. The age of participants across the studies ranged from 3 to 101 years, with a mean of 25.42 years. 48% of participants were male. All included studies were published between 2002 and 2016. Two of the 15 studies declared that the financial support was from companies that manufacture restorative material. Five studies were individually randomised parallel-group studies; six were cluster-randomised parallel-group studies; and four were randomised studies that used a split-mouth design. Eleven studies evaluated the effects of ART on primary teeth only, and four on permanent teeth. The follow-up period of the included studies ranged from 6 months to 36 months. We judged all studies to be at high risk of bias.For the main comparison of ART compared to conventional treatment using the same material: all but two studies used high-viscosity glass ionomer (H-GIC) as the restorative material; one study used a composite material; and one study used resin-modified glass ionomer cement (RM-GIC)).Compared to conventional treatment using H-GIC, ART may increase the risk of restoration failure in the primary dentition, over a follow-up period from 12 to 24 months (OR 1.60, 95% CI 1.13 to 2.27, five studies; 643 participants analysed; low-quality evidence). Our confidence in this effect estimate is limited due to serious concerns over risk of performance and attrition bias. For this comparison, ART may reduce pain during procedure compared with conventional treatment (MD -0.65, 95% CI -1.38 to 0.07; 40 participants analysed; low-quality evidence)Comparisons of ART to conventional treatment using composite or RM-GIC were downgraded to very low quality due to indirectness, imprecision and high risk of performance and attrition bias. Given the very low quality of the evidence from single studies, we are uncertain about the restoration failure of ART compared with conventional treatment using composite over a 24-month follow-up period (OR 1.11, 95% CI 0.54 to 2.29; one study; 57 participants) and ART using RM-GIC in the permanent teeth of older adults with root caries lesions over a six-month follow-up period (OR 2.71, 95% CI 0.94 to 7.81; one study; 64 participants).No studies reported on adverse events or costs.

AUTHORS' CONCLUSIONS

Low-quality evidence suggests that ART using H-GIC may have a higher risk of restoration failure than conventional treatment for caries lesions in primary teeth. The effects of ART using composite and RM-GIC are uncertain due to the very low quality of the evidence and we cannot rely on the findings. Most studies evaluated the effects of ART on the primary dentition.Well-designed RCTs are required that report on restoration failure at clinically meaningful time points, as well as participant-reported outcomes such as pain and discomfort. Due to the potential confounding effects from the use of different dental materials, a robust body of evidence on the effects of ART compared with conventional treatment using the same restoration material is necessary. We identified four ongoing trials that could provide further insights into this area.

Effect of Refurbishing Amalgam and Resin Composite Restorations After 12 Years: Controlled Clinical Trial

OBJECTIVES

The aim of this study was to clinically evaluate posterior amalgam and resin composite restorations refurbished over a period of 12 years by investigating the influence of refurbishing on the survival of restorations and comparing their behaviors with respect to controls.

METHODS AND MATERIALS

Thirty-four patients were enrolled, ages 18 to 80 years, with 174 restorations, 48 restorations of resin composite (RC), and 126 restorations of amalgam (AM). Restorations with localized defects in anatomy, roughness, luster, or marginal staining that were clinically judged as suitable for refurbishing according to US Public Health Service (USPHS) Ryge criteria were assigned to group A-refurbishing (n=85; 67 AM, 18 RC)-or group B-control (n=89; 59 AM, 30 RC); the quality of the restorations was evaluated blindly according to the modified USPHS criteria. Two observers conducted evaluations at the initial state (k=0.74) and after one to five, 10, and 12 years (k=0.88). Wilcoxon, Friedman, and Mantel-Cox tests were performed to compare the groups, respectively.

RESULTS

After 12 years, both groups experienced a similar decline, except for an evidently better performance in marginal adaptation in RC control (p=0.043) and in anatomy in AM refurbished (p=0.032).

CONCLUSIONS

After 12 years, no difference was found in the clinical condition and longevity of the refurbished restorations compared to the control group.

Impact of Different Surgeons on Dental Implant Failure

PURPOSE

To assess the influence of several factors on the prevalence of dental implant failure, with special consideration of the placement of implants by different dental surgeons.

MATERIALS AND METHODS

This retrospective study is based on 2,670 patients who received 10,096 implants at one specialist clinic. Only the data of patients and implants treated by surgeons who had inserted a minimum of 200 implants at the clinic were included. Kaplan-Meier curves were stratified with respect to the individual surgeon. A generalized estimating equation (GEE) method was used to account for the fact that repeated observations (several implants) were placed in a single patient. The factors bone quantity, bone quality, implant location, implant surface, and implant system were analyzed with descriptive statistics separately for each individual surgeon.

RESULTS

A total of 10 surgeons were eligible. The differences between the survival curves of each individual were statistically significant. The multivariate GEE model showed the following variables to be statistically significant: surgeon, bruxism, intake of antidepressants, location, implant length, and implant system. The surgeon with the highest absolute number of failures was also the one who inserted the most implants in sites of poor bone and used turned implants in most cases, whereas the surgeon with the lowest absolute number of failures used mainly modern implants. Separate survival analyses of turned and modern implants stratified for the individual surgeon showed statistically significant differences in cumulative survival.

CONCLUSION

Different levels of failure incidence could be observed between the surgeons, occasionally reaching significant levels. Although a direct causal relationship could not be ascertained, the results of the present study suggest that the surgeons' technique, skills, and/or judgment may negatively influence implant survival rates.

Risk Factors associated with Dental Implant Failure: A Study of 302 Implants placed in a Regional Center

AIM

The aim of this research is to determine which risk factors are associated with dental implant failure and survival.

MATERIALS AND METHODS

Data pertaining to patients who received one or more dental implants from 2011 to 2013 in a regional center were retrospectively reviewed. This included a total of 302 Biomet 3i NanoTite Tapered Certain implants placed in 177 patients. All patients were followed up until the end of 2015.

RESULTS

This study found an overall success rate of 95%. Statistically significant factors that were found to affect implant survival were implant length, surgical technique, and presence of diabetes mellitus DM. Age, gender, body mass index (BMI), implant site, smoking, and variable operators were not found to have any significant implant on implant survival.

CONCLUSION

This study has demonstrated that the incidence of implant failure and its complications is affected by a number of important factors that clinicians should consider when assessing patients. A follow-up study with a larger sample size, longer follow-up period, and details of the type of prosthetic rehabilitation would be beneficial in producing more definitive conclusions which may improve clinical practice.

CLINICAL SIGNIFICANCE

Dental implants play an important role in modern-day dental rehabilitation. It is vital that clinicians understand the impact of variable risk factors on implant survival. This study will add to the growing literature on the subject.

Efficacy of conventional treatment with composite resin and atraumatic restorative treatment in posterior primary teeth: study protocol for a randomised controlled trial

INTRODUCTION

Despite the widespread acceptance of conventional treatment using composite resin in primary teeth, there is limited evidence that this approach is the best option in paediatric clinics. Atraumatic restorative treatment (ART) using high-viscosity glass ionomer cement has gradually become more popular because it performs well in clinical studies, is easy to handle and is patient friendly. Therefore, the aim of this randomised clinical trial study is to compare the restoration longevity of conventional treatment using composite resin with that of ART in posterior primary teeth. As secondary outcomes, cost-efficacy and patient self-reported discomfort will also be tested.

METHODS AND ANALYSIS

Children aged 3-6 years presenting with at least one occlusal and/or occlusal-proximal cavity will be randomly assigned to one of two groups according to the dental treatment: ART (experimental group) or composite resin restoration (control group). The dental treatment will be performed at a dental care trailer located in an educational complex in Barueri/SP, Brazil. The unit of randomisation will be the child. A sample size of 240 teeth with occlusal cavities and 188 teeth with occlusal-proximal cavities has been calculated. The primary outcome will be restoration longevity, which will be clinically assessed after 6, 12, 18 and 24 months by two examiners. The duration of the dental treatment and the cost of all materials used will be considered when estimating the cost-efficacy of each treatment. Individual discomfort will be measured after each dental procedure using the Facial Scale of Wong-Baker.

ETHICS AND DISSEMINATION

This clinical trial was approved by the local ethics committee from the Faculty of Dentistry of the University of São Paulo (registration no. 1.556.018). Participants will be included after their legal guardians have signed an informed consent form containing detailed information about the research.

TRIAL REGISTRATION NUMBER

www.clinicaltrials.gov, NCT02562456; Pre-results.

Placement and replacement rates of amalgam and composite restorations on posterior teeth in a military population

OBJECTIVE

Replacement rates of direct dental restorations have been reported to be 37% to 70%, occupying a large proportion of a general dentist's time. Variations in the rate of initial placement and replacement of direct dental restorations may be associated with material placed (amalgam or composite), age, caries risk of the patient, and other factors. The purpose of this research was to clarify where the majority of patient care time is spent as a restorative Army dentist regarding either the initial placement or replacement of failed restorations; and how the location, caries risk, and material used (amalgam or composite) affects replacement rates.

METHODS

This retrospective cross-sectional study gathered data from 600 randomly selected military patient dental records. All paper records were reviewed and cross checked with the digital record and digital x-ray databases. Record review was limited to all direct dental restorations placed in the posterior dentition within the past 2 years (March 2011 to March 2013). Statistical analysis was accomplished using chi-square tests and logistic regression analyses.

RESULTS

Of the 600 charts reviewed, 525 were male, 75 were female, with an average age of 26 years (SD=6), ranging from 17 to 54 years. A third of the patients were classified as high, moderate, and low caries risk, respectively. The total number of posterior direct dental restorations placed was 2,117. Initial restorations totaled 1,429 (67.5%), and replacement restorations placed totaled 688 (32.5%). Four hundred forty-one of the 688 direct dental restorations replaced were amalgam (64%), the 247 remaining direct restorations replaced were composite (36%). Mandibular first molar dental restorations were replaced the most often (23.1%) while mandibular first premolar restorations were replaced the least often (0.9%). Older patients were more likely to have replacement of an existing restoration.

CONCLUSIONS

Military dentists spend about one-third (32.5%) of their time replacing existing direct dental restorations. The majority of direct dental restorations placed and replaced were amalgam. No significant difference was found between composite and amalgam restorations. Location was shown to be significant with first molars and second molar restorations failing with the highest frequency. There was no significant difference found between male and female patients. As patient's age increased, the number of replacement restorations also increased.

Epidemiology of Implant Mortality Disparity Among Intraoral Positions and Prosthesis Types

PURPOSE

To examine the disparity of single-crown implant failure with a similar loss of the splinted prosthesis in differing anatomical locations while controlling for other demographic and clinical variables that may confound the relationship between prosthesis types and implant loss.

MATERIALS AND METHODS

A multicenter retrospective cohort study was designed to include patients treated with dental implants from 2003 to 2014. The variables included age, sex, systemic disease, bone graft, implant placement date, position of dental implant, length of dental implant, diameter of dental implant, loading time, type of prosthesis, type of opposing occlusion, latest check date, and survival or loss of the dental implant. The demographic and clinical variables' influence on the survival of dental implants was estimated by the Kaplan-Meier method. The position and diameter were adjusted for the accurate estimation of the relationship between the prosthesis type and survival of the dental implant with the Cox proportional hazard method.

RESULTS

A total of 1,151 dental implants from 403 patients were ascertained. After adjusting for the confounding effect of position and diameter, single-crown prostheses were 38.1 (95% CI: 15.1-118) times more likely to be lost than the connected-type prostheses. For single-crown implants, the waiting time for osseointegration before loading was the highest for the maxillary molar position and the lowest for the mandibular molar position (P < .0001), while the most frequent implant loss occurred in the maxillary anterior area, and the second frequent area was the maxillary molar position; the lowest occurrence of implant loss was for the mandibular molar position. This disparity was statistically significant (P = .0271).

CONCLUSION

Despite the high survival rates of endosseous implants as a whole, since the variation of implant loss was observed among the different anatomical positions for single-crown implants, special attention has to be given to the maxillary anterior and maxillary molar positions. A longer healing time assuming compensation for disadvantageous bone quality was not directly effective in increasing implant longevity in the vulnerable positions.

Comparison of Preprosthetic Implant Complications and Failures Between Obese and Nonobese Patients

PURPOSE

Obesity as a systemic risk factor associated with implant failure or other complications has not been studied. The aim of this study was to compare the frequency of implant failure and complications between obese and nonobese patients.

MATERIALS AND METHODS

Charts from 220 partially edentulous patients with 321 implants were examined for demographic information, medical health history, diabetes, smoking, patient-reported height and weight, periodontal status (no, mild, moderate, or severe periodontitis), tooth number, date of the implant and prosthesis placement, and treatment notes pertinent to the complications or failure. Subjects were classified according to their body mass index (BMI) as normal (18.5 to 24.5 kg/m(2)), overweight (25 to 29.9 kg/m(2)), or obese (≥ 30 kg/m(2)) based on self-reported height and weight. Variables including sex, smoking, diabetes, and periodontal condition were considered as confounders. Data were analyzed to examine differences in frequency of complications and occurrence of failures.

RESULTS

Implant failure was low (2.1%) and did not differ by BMI category. Compared with normal BMI patients, obese patients had increased odds of experiencing an implant complication (OR = 4.9, 95% CI [1.4, 17.6]) after adjustment for other variables. Diabetes was not associated with an increased risk of complications; obese patients with diabetes had decreased odds of an implant complication compared with obese patients without diabetes.

CONCLUSION

No association was observed between obesity and implant failures. BMI category was associated with implant complications; obese patients have greater odds of experiencing implant complications postsurgically. Treating obese patients with the existing protocol for diabetic patients (antibiotic regimens, more frequent follow-up, and maintenance appointments) may improve clinical outcomes.

Split-Mouth Comparison of Splinted and Nonsplinted Prostheses on Short Implants: 3-Year Results

PURPOSE

To compare splinted and individual restorations supported by short implants featuring an internal connection utilizing a split-mouth design.

MATERIALS AND METHODS

Splinted and nonsplinted implant crowns were prospectively compared in 18 patients. After verifying the need for at least two consecutive implants bilaterally, computed tomography scans were made, virtual planning was done, and qualifying patients were enrolled. Implants were placed using a two-stage surgical approach. After 3 to 5 months, patients were randomly restored with splinted prostheses on their left or right side. Nonsplinted restorations were made for contralateral sides. Radiographs were taken at prostheses seating and yearly exams. Radiographic bone levels were analyzed and compared (SAS 9.4) to determine differences between splinted and nonsplinted implants. Complications such as screw loosening, screw breakage, or porcelain fracture were assessed at recalls.

RESULTS

Eighteen patients (9 men and 9 women) with an age range from 49 to 76 years (mean = 56 years), received ≥ 4 implants in symmetrical posterior locations. Implants (n = 82) ranged in length from 6 to 11 mm with 70 implants ≤ 9 mm and 38 implants = 6 mm. At the time of this report, 3-year examinations and bone level comparisons were completed on 15 patients. One patient was lost to follow-up, one deviated from study protocol by smoking, and one was splinted on both sides due to repeated screw breakage. Screw loosening occurred in five patients on their nonsplinted side. These were 6-mm implants except for one patient. Porcelain chipping occurred for one patient on the splinted side. One 6-mm-length nonsplinted implant was lost after loading; this implant was successfully replaced after grafting. This patient had a total of six implants placed; ongoing bone level measurements included two pairs of implants only. For all implants combined, there was no significant difference (P > .05) at 1, 2, or 3 years for mean bone change around splinted and nonsplinted implants. However, length was identified as a significant factor (P = .0039). Further analysis revealed statistically significant differences between splinted and nonsplinted for 6-mm length implants at 24 (P = .0061) and 36 (P = .0144) months. A gain in mean bone level of 0.41 and 0.37 mm was observed for nonsplinted implants at 24 and 36 months compared with baseline. Bone levels for the splinted 6-mm implants were not statistically different from baseline measurements (P > .05).

CONCLUSION

Results of this prospective 3-year study of splinted ipsilateral and nonsplinted contralateral implants in 15 patients show: (1) peri-implant bone levels around splinted and nonsplinted implants were not statistically different for implants greater than 6 mm in length; (2) nonsplinted 6-mm implants revealed a gain in bone at 24 and 36 months compared with baseline; (3) all screw loosening only occurred on the nonsplinted side for 5 of 15 patients; and (4) implant loss after loading occurred for one 6-mm nonsplinted implant.

Survival of Implants Using the Osteotome Technique With or Without Grafting in the Posterior Maxilla: A Systematic Review

PURPOSE

The aim of this review was to systematically appraise survival rates of implants placed using the osteotome technique with and without grafting in the published literature.

MATERIALS AND METHODS

An electronic search was conducted to identify prospective and retrospective studies on osteotome sinus floor elevation published between January 1, 2000 and October 30, 2015. Studies were included that (1) involved use of the osteotome technique with or without grafting; (2) provided data regarding the implant survival rates, residual bone height (RBH), and grafting materials; and (3) reported mean follow-up of at least 1 year after functional loading and included a minimum of 10 patients. The mean weighted cumulative implant survival rates were used to compare the two treatment strategies-grafted or nongrafted. The influence of RBH and implant length on weighted cumulative implant survival was also evaluated.

RESULTS

After search and evaluation of the literature according to the inclusion criteria, 34 studies involving 1,977 patients and 3,119 implants were included. Eighty-four out of 102 implant failures documented in the studies occurred within 1 year of functional loading. Statistically significant differences in the cumulative survival rates were found in the graft and nongraft groups (95.89% and 97.30%, respectively; P = .05). In the nongraft group, no statistically significant difference in the cumulative survival rate was found when implants were placed at RBH < 5 mm or ≥ 5 mm (95.04% and 97.63%, respectively; P = .12). In the graft group, however, a statistically significant difference was found when implants were placed at RBH < 5 mm or ≥ 5 mm (92.19% and 97.59%, respectively; P < .01). Significantly lower weighted mean cumulative implant survival rates were found in the shorter (< 8 mm) implant group than in the longer (≥ 8 mm) implant group (83.33% and 96.28%, respectively; P < .01).

CONCLUSION

The cumulative survival rates were significantly higher in the nongraft group than in the graft group. Early failures (< 1 year functional loading) accounted for the vast majority of the implant failures. The cumulative survival rates in the graft group were significantly lower when the RBH was < 5 mm, while the cumulative survival rates in the nongraft group demonstrated no statistically significant difference based on RBH. Shorter (< 8 mm) implants demonstrated significantly lower cumulative survival rates than longer implants.

Repair restorations: Questionnaire survey among dentists in the Canton of Zurich, Switzerland

The aim of this study was to carry out a representative survey on the implementation of and experience with repairs of single-tooth restorations among dentists in the Canton of Zurich, Switzerland. An anonymous questionnaire was sent to all 1,411 dentists registered in the Canton of Zurich; 38.9% of the delivered questionnaires were returned and 35.3% could be evaluated. The statistical analysis comprised Kendall’s rank correlation coefficient (tau), Wilcoxon signed-rank tests, and Kruskal-Wallis tests. The level of significance was set at p≤0.05. Repair restorations are frequently made (composite: 98.5%, ceramic: 88.9%, crowns: 86.5%, metal: 54.6%, amalgam: 51.5%). Main indications for repairs were the partial loss of an existing restoration or of the adjacent dental hard substance, while restoration failures due to secondary caries were repaired to a lesser extent. The decision to repair is largely dependent on the size of the defect (90%), the size of the original restoration (63%), and the material of the failed restoration (84%). Repair restorations are most frequently made with composite following adequate conditioning of the repair surface. A majority of the dentists rate the lifespan of repair restorations as reduced in comparison with newly made restorations. In summary, repairs of defective single-tooth restorations are frequently performed by dentists in the Canton of Zurich, Switzerland, and constitute a well-established treatment procedure.

Dental Implants in the Elderly Population: A Long-Term Follow-up

PURPOSE

The objectives of this study were to evaluate implant survival and success in the elderly population and to assess indicators and risk factors for success or failure of dental implants in older adults (aged 60 years and older).

MATERIALS AND METHODS

This historical prospective study was developed from a cohort of patients born prior to 1950 who received dental implants in a single private dental office. Implant survival and marginal bone levels were recorded and analyzed with regard to different patient- and implant-related factors.

RESULTS

The study examined 245 patient charts and 1,256 implants from one dental clinic. The mean age at the time of implant placement was 62.18 ± 8.6 years. Smoking was reported by 9.4% of the cohort studied. The overall survival rate of the implants was 92.9%; 7.1% of the implants had failed. Marginal bone loss depicted by exposed threads was evident in 23.3% of the implants. Presenting with generalized periodontal disease and/or severe periodontal disease negatively influenced the survival probability of the implant. Implants placed in areas where bone augmentation was performed prior to or during implant surgery did not have the same longevity compared with those that did not have augmentation prior to implantation.

CONCLUSION

The overall findings concluded that implants can be successfully placed in older adults. A variety of factors are involved in the long-term success of the implant, and special consideration should be taken prior to placing implants in older adults to limit the influence of those risk factors.

The Up-to-14-Year Survival and Complication Burden of 256 TiUnite Implants Supporting One-Piece Cast Abutment/Metal-Ceramic Implant-Supported Single Crowns

PURPOSE

To assess the estimated cumulative survival (ECS) and explore the technical and biologic complications of 256 TiUnite implants (Nobel Biocare) supporting one-piece cast abutment/metal-ceramic implant-supported single crowns (ISCs) in situ for up to 14 years.

MATERIALS AND METHODS

A prospective sequentially recruited cohort of 207 patients received 256 metal-ceramic ISCs on TiUnite implants between 2001 and 2014. All but 24 patients with 27 crowns were clinically evaluated between January 2014 and April 2015 in conjunction with or in addition to their tailored maintenance program. Radiographs were obtained, and any previously recorded treatments associated with the crowns were tabulated. The ECS and standard errors were calculated with the life table actuarial method and Greenwood's formula, respectively. The log rank test was applied to assess differences between anterior and posterior crowns. Complication incidence, severity, and economic burden, measured in time/cost accounting units (TAUs), were tallied and compared descriptively. Independent groups were compared with the Mann-Whitney U test and related groups with the Wilcoxon Signed Rank Test.

RESULTS

The mean clinical service time of the crowns was 5.61 years (44 ≥ 10 years). The 14-year ECS was 95.95% ± 3.20% with no significant difference between anterior and posterior prostheses. Only seven implants lost marginal bone ≥ one thread from the time of crown insertion. There were 30 nonterminal complications (16 biologic, 14 mechanical). The associated economic burden was low (n = 35 TAUs).

CONCLUSION

High gold-alloy one-piece cast abutment/metal-ceramic ISCs on TiUnite implants exhibited excellent longevity and few complications over 14 years.

Patterns of Restorative Failure among Khat and Shammah Users in Jazan City, Kingdom of Saudi Arabia: A Cross-sectional Survey

INTRODUCTION

The effect of Khat and Shammah habits, with the parafunctional jaw activities that accompany them, on the integrity of the natural dentition, dental restorations, and prostheses has not yet been investigated. This study is the first attempt to identify the patterns of restorative failure among Khat chewers and Shammah users in Jazan City, Kingdom of Saudi Arabia.

MATERIALS AND METHODS

A cross-sectional study was conducted in 294 recruits among dental clinics in Jazan City, Kingdom of Saudi Arabia, from October 1, 2015, to April 30, 2016. The patients were surveyed and examined to identify the type of restorations/prosthesis they had and their failures. Bivariate analysis was conducted to investigate the association of the restorative failure with the demographic variables. General linear model was performed to investigate the association between restorations/prostheses failure and Khat/Shammah use with the controlling factors of age and gender as independent variables.

RESULTS

Khat/Shammah use was statistically significantly associated with restorative failure (p < 0.05) relative to amalgam, composite, crowns, fixed partial dentures, removable partial dentures, and complete dentures. In addition, a significant association of restorative failure was observed with gender, education, and brushing.

CONCLUSION

Consumption of Khat/Shammah may be attributed as one of the reasons associated with restorative failure among the Saudi population.

What do sales data tell us about implant survival?

Objective

The aim of this study was to evaluate the influence of implant diameter, length and shape on a surrogate parameter of implant survival; i.e. the implant return rate in a big data analysis.

Materials and methods

A retrospective study was conducted and the factors influencing the success rates of 69,377 sold implants over a seven-year period were evaluated. The osseointegration program of a reseller provides reliable data of a single country. Implant loss rates were investigated using logistic regression models and regressed by implant type, diameter, and length.

Results

The return rate of 69,377 sold implants was 2.78% and comparable to implant loss rates in previous published prospective studies as its surrogate parameter. A total of 80% of implant returns had occurred within 157 days, and an additional 15% within 750.25 days. Diameters of 3.8 to 5.0mm showed the lowest return rates with its bottom in the 4.3mm implant whilst 6.0mm implants had significantly higher return rates. In comparison to the most sold implant length (13mm) shorter implants showed significantly higher early return rates.

Conclusions

The study provides evidence that in cases of standard indications and sufficient bone, the use of screw typed dental implants with 3.8 or 4.3 diameter and 11 or 13 mm length shows the lowest implant return rates. Other implants may be selected only in specific indications.

Long-Term Results of Peri-implant Conditions in Periodontally Compromised Patients Following Lateral Bone Augmentation

PURPOSE

The aim of this retrospective study was to compare long-term (≥ 5 years) outcomes of implants placed in patients treated for chronic periodontitis versus those placed in periodontally healthy patients. In both groups, the implants were placed in alveolar ridges that were laterally augmented with autogenous bone block grafts using a split bone block technique.

MATERIALS AND METHODS

Two hundred ninety-two patients were screened in the course of supportive periodontal treatment examinations. Nonsmoking patients without any severe systemic diseases who had adhered to regular supportive periodontal treatment for a minimum of 5 years after undergoing autogenous lateral grafting (using the split bone block technique), implant placement, and prosthetic reconstructions were classified into two groups based on their presurgical status: periodontally healthy patients (PHP) and periodontally compromised patients (PCP).

RESULTS

Clinical outcomes for 77 patients, 38 PHP and 39 PCP, were examined. All had been successfully treated for severe lateral atrophy and received a total of 241 endosseous implants between 2002 and 2008. At the final examination, mean bleeding on probing was 7.08% ± 7.27% in PHP and 14.49% ± 18.14% in PCP, a statistically significant difference. Significantly higher Plaque Index and more recession were associated with a narrow (< 2 mm) width of keratinized mucosa.

CONCLUSION

Implants in alveolar ridges laterally augmented using a split bone block technique revealed similar clinical peri-implant conditions in both PHP and PCP. Using autogenous bone block grafts without biomaterials resulted in long-term peri-implant tissue stability.

Internal- vs External-Connection Single Implants: A Retrospective Study in an Italian Population Treated by Certified Prosthodontists

PURPOSE

The design of an implant connection that allows prosthetic suprastructures to be attached to implants has long been debated in the dental literature. The goal of this retrospective study was to evaluate the 5-year clinical results for a large number of single implants restored by certified prosthodontists in an attempt to establish whether different clinical outcomes could be detected for external- or internal-connection implants.

MATERIALS AND METHODS

All single implants with internal or external connections inserted in 27 private dental practices from January 1, 2003 to December 31, 2007 were evaluated. An initial statistical analysis was performed to describe the sample population at baseline and then to compare the two types of implant-abutment connection configurations and their clinical outcomes. All data were statistically analyzed with STATA12 (StataCorp).

RESULTS

Twenty-eight of the 85 active members of the Italian Academy of Prosthetic Dentistry (AIOP) participated in this study. The sample included 1,159 patients and 2,010 implants. Of the implants, 75 were dropped because there was no information about follow-up. Of the remaining implants, 1,431 (74.0%) were followed for at least 5 years, and 332 implants (17.2%) were followed for more than 8 years. Nearly 99% (98.9%) of the implants survived. The difference between the survival frequencies of the two types of implant-abutment connection configurations was not significant for each negative event (log-rank test, P > .05). There was no difference between the two types of implants regarding restoration fracture, implant screw loosening, and peri-implant disease.

CONCLUSION

Within the limitations of this study, it can be suggested that there is no difference in clinical outcomes of single restorations joined to internal- or external-connection implants.

Survival of Dental Implants Placed in Grafted and Nongrafted Bone: A Retrospective Study in a University Setting

PURPOSE

To compare dental implant survival rates when placed in native bone and grafted sites. Additionally, risk factors associated with dental implant loss were identified. This study was based on the hypothesis that bone grafting has no effect on implant survival rates.

MATERIALS AND METHODS

A retrospective chart review was conducted for patients receiving dental implants at the University of Texas, School of Dentistry from 1985 to 2012. Exclusion criteria included patients with genetic diseases, radiation and chemotherapy, or an age less than 18 years. To avoid misclassification bias, implants were excluded if bone grafts were only done at the same time of placement. Data on age, sex, tobacco use, diabetes, osteoporosis, anatomical location of the implant, implant length and width, bone graft, and professional maintenance were collected for analysis.

RESULTS

A total of 1,222 patients with 2,729 implants were included. The cumulative survival rates at 5 and 10 years were 92% and 87% for implants placed in native bone and 90% and 79% for implants placed in grafted bone, respectively. The results from multivariate analysis (Cox regression) indicated no significant difference in survival between the two groups; having maintenance therapy after implant placement reduced the failure rate by 80% (P < .001), and using tobacco increased the failure rate by 2.6-fold (P = .001).

CONCLUSION

There was no difference in the dental implant survival rate when implants were placed in native bone or bone-grafted sites. Smoking and lack of professional maintenance were significantly related to increased implant loss.

Survival of Adhesive Restorations for Primary Molars: A Systematic Review and Metaanalysis of Clinical Trials

PURPOSE

The purpose of this study was to assess the scientific evidence regarding the survival and clinical performance of adhesive materials for primary molars, comparing composite resin (CR), conventional glass ionomer cement (GIC), resin-modified glass ionomer (RMGIC), silver-reinforced glass ionomer cement, and compomer.

METHODS

Six databases were searched without restrictions regarding language or year of publication. Meta-analysis was conducted; risk ratios (RRs) and 95 percent confidence intervals (95% CI) were calculated.

RESULTS

Eleven clinical trials were included. Two studies found that the median survival time (MST) of SRGIC was less than that of GIC and RMGIC (P<0.005), and two studies found that the GIC had a lower MST than both RMGIC and compomer (P<0.05). Meta-analysis for CR, compomer, and RMGIC was conducted. These materials did not differ significantly regarding the number of restorations that survived over 24 months: CR versus RMGIC (RR equals 1.12, 95% CI equals 0.96 to 1.31); CR versus compomer (RR equals 1.04; 95% CI equals 0.96 to 1.13); and compomer versus RMGIC (RR equals 1.03; 95% CI equals 0.84 to 1.27).

CONCLUSIONS

Silver-reinforced glass ionomer cement has the worst survival rate among ionomers, and adhesive materials with a resin component have similar survival rates.

We May Have Done Something Right: Composite Restorations at the College of Dentistry, University of Tennessee Health Science Center

The success of composite restorations requires meticulous clinical technique in addition to reliable restorative materials and armamentarium. Early failure of restorations is undesirable and are usually replaced at no cost to patients. A metaanalysis study reported a mean annual failure rate of 1.46% for posterior composite restorations. At the University of Tennessee Health Science Center College of Dentistry (UTHSC CoD) predoctoral clinic the percentage of posterior composite restorations replaced within 12 months, retrieved from 2007-2014 electronic chart 'redo' records, was on average 0.58%. Several factors may have contributed to the quality of composite restorations placed by novice clinicians with modest experience. Student doctors are educated about composite placement in preclinical courses and then work under close supervision during their clinical training. This article describes restorative techniques for composites and the rationales taught at the UTHSC CoD Department of Restorative Dentistry. The objective is to share the information, which can be adopted or modified by general practitioners in daily practice.

Utilization of Ceramic Inlays for Sealing Implant Prostheses Screw Access Holes: A Case-Control Study

PURPOSE

The aim of this study was to evaluate, in a case control study, the esthetic and functional clinical performance of ceramic inlays used for covering the screw access hole in single monolithic lithium disilicate full-contour crowns bonded on computer-aided design/computer-aided manufacturing (CAD/CAM) prefabricated titanium abutments in order to eliminate the drawbacks of alternative restorative methods.

MATERIALS AND METHODS

Twenty-eight patients with missing teeth in the lateral areas (premolars and molars) received screw-retained implant restorations. In half of the restorations (n = 14), composite fillings were used to seal the access hole (control group), while the other half was sealed with ceramic inlays (test group). To determine the restoration occlusal wear, impressions were obtained after the restorations were finalized, at 1 year, and at 2 years follow-up. The casts were scanned with a 3D Scanner Design System recording the anatomical surfaces of the white model replicates. Wear amounts (μm) were calculated as the maximum loss in height of the occlusal surface. The clinical evaluation was carried out using a kit specifically designed for assessing the FDI criteria. Statistics were performed using analysis of variance (ANOVA).

RESULTS

A total of 58 restorations were delivered, and after 2 years of follow-up, the wear values were 228.20 ± 54.68 μm for the control group and 65.20 ± 7.24 μm for the ceramic inlay group. One-way ANOVA showed significant differences among the vertical loss between these two groups (P < .001). Clinical outcomes according to the FDI score for assessing dental restorations revealed substantial deterioration within 2 years of follow-up.

CONCLUSION

The use of ceramic inlays appears to be a predictable, esthetic, and successful method of sealing the screw holes of the screw-retained implant restorations.

Success and Survival Rates of Dental Implants Restored at an Undergraduate Dental Clinic: A 13-Year Retrospective Study with a Mean Follow-up of 5.8 Years

PURPOSE

The purpose of this study was to evaluate the clinical, radiographic, and patient-based outcomes of dental implants placed at an undergraduate student dental clinic.

MATERIALS AND METHODS

A retrospective study was performed to determine the success and survival rates of dental implants placed at the undergraduate dental clinic at Dalhousie University between January 1999 and January 2012. Only patients with a minimum of 1-year follow-up were included. Clinical and radiographic assessments determined implant success and survival rates. Questionnaires recorded patients' satisfaction with esthetics, comfort, and ease of hygiene.

RESULTS

Of the 352 patients (n = 591 implants) who received implants over 13 years, 165 patients completed the clinical and radiographic examinations. By the end of the study period, demographic information and implant characteristics were collected for 111 (n = 217 implants; 47.5% in the maxilla, 52.6% in the mandible) of these patients. Of those assessed clinically, 36.4% were males and 63.6% females, with a mean age of 56.1 ± 14.15 years (range, 17 to 86 years) at the time of implant placement. The mean follow-up period was 5.8 years (range, 1 to 13 years). The overall implant success and survival rates were 88.0% and 97.2%, respectively. No observable bone loss was evident in 88.0% of the surviving implants. There were no implant fractures. Most patients (91.2%) were very satisfied with the implant restoration appearance, 88.0% were very comfortable with the implant, 92.6% were very satisfied with their ability to chew, and 84.8% reported easy hygiene maintenance at the implant sites.

CONCLUSION

Implant success and survival in an undergraduate student clinic were comparable to those reported in the literature. It seems that inexperienced students were able to provide restorations that were very satisfying to the patients.

Stiffness, strength, and failure modes of implant-supported monolithic lithium disilicate crowns: influence of titanium and zirconia abutments

PURPOSE

The objective of this study was to evaluate stiffness, strength, and failure modes of monolithic crowns produced using computer-aided design/computer-assisted manufacture, which are connected to diverse titanium and zirconia abutments on an implant system with tapered, internal connections.

MATERIALS AND METHODS

Twenty monolithic lithium disilicate (LS2) crowns were constructed and loaded on bone level-type implants in a universal testing machine under quasistatic conditions according to DIN ISO 14801. Comparative analysis included a 2 × 2 format: prefabricated titanium abutments using proprietary bonding bases (group A) vs nonproprietary bonding bases (group B), and customized zirconia abutments using proprietary Straumann CARES (group C) vs nonproprietary Astra Atlantis (group D) material. Stiffness and strength were assessed and calculated statistically with the Wilcoxon rank sum test. Cross-sections of each tested group were inspected microscopically.

RESULTS

Loaded LS2 crowns, implants, and abutment screws in all tested specimens (groups A, B, C, and D) did not show any visible fractures. For an analysis of titanium abutments (groups A and B), stiffness and strength showed equally high stability. In contrast, proprietary and nonproprietary customized zirconia abutments exhibited statistically significant differences with a mean strength of 366 N (Astra) and 541 N (CARES) (P < .05); as well as a mean stiffness of 884 N/mm (Astra) and 1,751 N/mm (CARES) (P < .05), respectively. Microscopic cross-sections revealed cracks in all zirconia abutments (groups C and D) below the implant shoulder.

CONCLUSION

Depending on the abutment design, prefabricated titanium abutment and proprietary customized zirconia implant-abutment connections in conjunction with monolithic LS2 crowns had the best results in this laboratory investigation.

A long-term retrospective analysis of survival rates of implants in the mandible

PURPOSE

To retrospectively analyze the survival rate of endosseous dental implants placed in the edentulous or partially edentulous mandible over a long-term follow-up period of 10 years or more.

MATERIALS AND METHODS

The charts of patients who underwent mandibular implant placement at a private prosthodontics practice and received follow-up care for 10 years or more were included in this study. Implants were examined according to the following study variables: patient sex, patient age, degree of edentulism (fully vs partially edentulous), implant location, time of loading (delayed vs immediate), implant size and type, bone quality, prosthesis type, and the presence of other implants during placement.

RESULTS

The study sample was composed of 2,394 implants placed in 470 patients with 10 to 27 years of follow-up. Of these 2,394 implants, 176 failed, resulting in an overall cumulative survival rate (CSR) of 92.6%. A total of 1,482 implants were placed in edentulous mandibles, and 912 implants were placed in partially edentulous mandibles, with CSRs of 92.6% and 92.7%, respectively. Comparisons of the study variables with respect to CSR were largely nonsignificant. However, there were significant differences in CSRs between anterior vs posterior locations and rough- vs smooth-surfaced implants in addition to some prosthesis types, ages, and bone qualities. The overall CSR of 92.6% in the present study is high and comparable to survival rates observed in previous long-term analyses of mandibular implants. The significant differences observed between implant locations, patient age groups, bone qualities, and prostheses were not suggestive of any remarkable trends.

CONCLUSION

Patient sex, age, degree of edentulism, implant location, time of loading, implant size and type, bone quality, prosthesis type, and the presence of multiple implants did not result in any significant effect on long-term implant survival. The CSR observed after 10 to 27 years of follow-up in a single private prosthodontic center was high (92.6%) and supports the use of endosseous dental implants as a long-term treatment option for the rehabilitation of the edentulous and partially edentulous mandible.

Research Waste: How Are Dental Survival Articles Indexed and Reported?

PURPOSE

Research waste occurs when research is ignored, cannot be found, cannot be used, or is unintentionally repeated. This article aims to investigate how dental survival analyses were indexed and reported, and to discuss whether errors in indexing and writing articles are affecting identification and use of survival articles, contributing to research waste.

MATERIALS AND METHODS

Articles reporting survival of dental prostheses in humans (also known as time-to-event) were identified by searching 50 dental journals that had the highest Impact Factor in 2008. These journals were hand searched twice (Kappa 0.92), and the articles were assessed by two independent reviewers (Kappa 0.86) to identify dental survival articles ("case" articles, n = 95), likely false positives (active controls, n = 91), and all other true negative articles (passive controls, n = 6,769). This means that the study used a case:control method. Once identified, the different groups of articles were assessed and compared. Allocation of medical subject headings (MeSH) by MEDLINE indexers that related to survival was sought, use of words by authors in the abstract and title that related to survival was identified, and use of words and figures by authors that related to survival in the articles themselves was also sought. Differences were assessed with chi-square and Fisher's Exact statistics. Reporting quality was also assessed. The results were reviewed to discuss their potential impact on research waste.

RESULTS

Allocation of survival-related MeSH index terms across the three article groups was inconsistent and inaccurate. Statistical MeSH had not been allocated to 30% of the dental survival "case" articles and had been incorrectly allocated to 15% of active controls. Additionally, information reported by authors in titles and abstracts varied, with only two-thirds of survival "case" articles mentioning survival "statistics" in the abstract. In the articles themselves, time-to-event statistical methods, survival curves, and life tables were poorly reported or constructed. Overall, the low quality of indexing by indexers and reporting by authors means that these articles will not be readily identifiable through electronic searches, and, even if they are found, the poor reporting quality makes it unnecessarily difficult for readers to understand and use them.

CONCLUSION

There are substantial problems with the reporting of time-to-event analyses in the dental literature. These problems will adversely impact how these articles can be found and used, thereby contributing to research waste. Changes are needed in the way that authors report these studies and the way indexers classify them.

Three-Year Analysis of Fixed and Removable Telescopic Attachment-Retained Implant-Supported Dental Prostheses: Survival and Need for Maintenance

PURPOSE

The purpose of this retrospective clinical study was to evaluate the clinical outcomes of fixed implant-supported dental prostheses (FISDPs) and removable ISDPs (RISDPs) retained by telescopic attachments, the factors influencing survival, and the type and number of maintenance treatments required during the observation period.

MATERIALS AND METHODS

This retrospective clinical study is based on patients who were provided with ISDPs between 2004 and 2010. Patient sex, type of prosthesis, location, opposing dentition, and the effect of continuous follow-up on the probability of a favorable outcome, as well as the number of maintenance treatments, were analyzed. A statistical analysis was performed using the Kaplan-Meier method.

RESULTS

A sample of 233 patients with 157 FISDPs and 76 RISDPs supported by a total of 567 implants was randomized and included in the analysis. The mean observation period was 15.9 ± 15.4 months (maximum, 66.0 months). During the observation period, 3.9% of prostheses (7/157 FISDPs and 2/76 RISDPs) ceased to function and 2.3% of implants (13 implants) were lost. The mean survival time was 59.7 ± 2.3 months, with a survival probability of 90.2% after 3 years. Prostheses in the mandible showed significantly higher survival rates than those in the maxilla. Maintenance treatments had to be performed at an earlier stage for patients with RISDPs than for patients with FISDPs. In patients with a conventional removable prosthesis in the opposing arch, the time until maintenance was needed was significantly shorter.

CONCLUSION

Within the limitations of a retrospective study, it can be concluded that the FISDPs and RISDPs show equally good survival rates after 3 years in function. RISDPs showed a greater and earlier need for maintenance treatments during the first years in function.

Radiographic bone level changes of implant-supported restorations in edentulous and partially dentate patients: 5-year results

PURPOSE

To evaluate and compare crestal bone level changes and peri-implant status of implant-supported reconstructions in edentulous and partially dentate patients after a minimum of 5 years of loading.

MATERIALS AND METHODS

All patients who received a self-tapping implant with a microstructured surface during the years 2003 and 2004 at the Department of Prosthodontics, University of Bern, were included in this study. The implant restorations comprised fixed and removable prostheses for partially and completely edentulous patients. Radiographs were taken immediately after surgery, at impression making, and 1 and 5 years after loading. Crestal bone level (BIC) was measured from the implant shoulder to the first bone contact, and changes were calculated over time (ΔBIC). The associations between pocket depth, bleeding on probing (BOP), and ΔBIC were assessed.

RESULTS

Sixty-one implants were placed in 20 patients (mean age, 62 ± 7 years). At the 5-year follow-up, 19 patients with 58 implants were available. Implant survival was 98.4% (one early failure; one patient died). The average ΔBIC between surgery and 5-year follow-up was 1.5 ± 0.9 mm and 1.1 ± 0.6 mm for edentulous and partially dentate patients, respectively. Most bone resorption (50%, 0.7 mm) occurred during the first 3 months (osseointegration) and within the first year of loading (21%, 0.3 mm). Mean annual bone loss during the 5 years of loading was < 0.12 mm. Mean pocket depth was 2.6 ± 0.7 mm. Seventeen percent of the implant sites displayed BOP; the frequency was significantly higher in women. None of the variables were significantly associated with crestal bone loss.

CONCLUSION

Crestal bone loss after 5 years was within the normal range, without a significant difference between edentulous and partially dentate patients. In the short term, this implant system can be used successfully for various prosthetic indications.

Dental auxiliaries for dental care traditionally provided by dentists

BACKGROUND

Poor or inequitable access to oral health care is commonly reported in high-, middle- and low-income countries. Although the severity of these problems varies, a lack of supply of dentists and their uneven distribution are important factors. Delegating care to dental auxiliaries could ease this problem, extend services to where they are unavailable and liberate time for dentists to do more complex work. Before such an approach can be advocated, it is important to know the relative effectiveness of dental auxiliaries and dentists.

OBJECTIVES

To assess the effectiveness, costs and cost effectiveness of dental auxiliaries in providing care traditionally provided by dentists.

SEARCH METHODS

We searched the following electronic databases from their inception dates up to November 2013: the Cochrane Effective Practice and Organisation of Care (EPOC) Group's Specialised Register; Cochrane Oral Health Group's Specialised Register; the Cochrane Central Register of Controlled Trials (Issue 11, 2013); MEDLINE; EMBASE; CINAHL; Cochrane Database of Systematic Reviews; Database of Abstracts of Reviews of Effectiveness; five other databases and two trial registries. We also undertook a grey literature search and searched the reference list of included studies and contacted authors of relevant papers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), non-randomised controlled clinical trials (NRCTs), interrupted time series (ITSs) and controlled before and after studies (CBAs) evaluating the effectiveness of dental auxiliaries compared with dentists in undertaking clinical tasks traditionally performed by a dentist.

DATA COLLECTION AND ANALYSIS

Three review authors independently applied eligibility criteria, extracted data and assessed the risk of bias of each included study and two review authors assessed the quality of the evidence from the included studies, according to The Cochrane Collaboration's procedures. Since meta-analysis was not possible, we gave a narrative description of the results.

MAIN RESULTS

We identified five studies (one cluster RCT, three RCTs and one NRCT), evaluating the effectiveness of dental auxiliaries compared with dentists in providing dental care traditionally provided by dentists, eligible for inclusion in this review. The included studies, which involved 13 dental auxiliaries, six dentists, and more than 1156 participants, evaluated two clinical tasks/techniques: placement of preventive resin fissure sealants and the atraumatic restorative technique (ART). Two studies were conducted in the US, and one each in Canada, Gambia and Singapore.Of the four studies evaluating effectiveness in placing preventive resin fissure sealants, three found no evidence of a difference in retention rates of those placed by dental auxiliaries and dentists over a range of follow-up periods (six to 24 months). One study found that fissure sealants placed by a dental auxiliary had lower retention rates than one placed by a dentist after 48 months (9.0% with auxiliary versus 29.1% with dentist). The same study reported that the net reduction after 48 months in the number teeth exhibiting caries (dental decay) was lower for teeth treated by the dental auxiliary than the dentist (3 with auxiliary versus 60 with dentist, P value < 0.001).One study showed no evidence of a difference in dental decay after treatment with fissure sealants between groups. The one study comparing the effectiveness of dental auxiliaries and dentists in performing ART reported no difference in survival rates of the restorations (fillings) after 12 months.All studies were at high risk of bias and the overall quality of the evidence was very low, as assessed using the GRADE approach. In addition, four of the included studies were more than 20 years old; the materials used and the techniques assessed were out of date. We found no eligible studies comparing the effectiveness of dental auxiliaries and dentists in the diagnosis of oral diseases and conditions, in delivering oral health education and other aspects of health promotion, or studies assessing participants' perspectives including the acceptability of care received. None of the included studies reported adverse effects. In addition, we found no studies comparing the costs and cost-effectiveness of dental auxiliaries and dentists, their impact on access and equity of access to care that met the pre-specified inclusion criteria.

AUTHORS' CONCLUSIONS

We only identified five studies for inclusion in this review, all of which were at high risk of bias and four were published more than 20 years ago, highlighting the paucity of high-quality evaluations of the relative effectiveness, cost-effectiveness and safety of dental auxiliaries compared with dentists in performing clinical tasks. No firm conclusions could be drawn from the present review about the relative effectiveness of dental auxiliaries and dentists.

Interventions for replacing missing teeth: different types of dental implants

BACKGROUND

Dental implants are available in different materials, shapes and with different surface characteristics. In particular, numerous implant designs and surface modifications have been developed for improving clinical outcome. This is an update of a Cochrane review first published in 2002, and previously updated in 2003, 2005 and 2007.

OBJECTIVES

Primary: to compare the clinical effects of different root-formed osseointegrated dental implant types for replacing missing teeth for the following specific comparisons: implants with different surface preparations, but having similar shape and material; implants with different shapes, but having similar surface preparation and material; implants made of different materials, but having similar surface preparation and shape; different implant types differing in surface preparation, shape, material or a combination of these.Secondary: to compare turned and roughened dental implants for occurrence of early implant failure (before prosthetic loading) and occurrence of peri-implantitis.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 17 January 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 12), MEDLINE via OVID (1946 to 17 January 2014) and EMBASE via OVID (1980 to 17 January 2014). We placed no restrictions on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included any randomised controlled trial (RCT) comparing osseointegrated dental implants of different materials, shapes and surface properties having a follow-up in function of at least one year. Outcome measures were success of the implants, radiographic peri-implant marginal bone levels changes and incidence of peri-implantitis.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted screening, risk of bias assessment and data extraction of eligible trials in duplicate. We expressed results using fixed-effect models (if up to three studies were present in a meta-analysis) or random-effects models (when there were more than three studies) using mean differences (MD) for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). We reported the following endpoints: one, three, five and 10 years after functional loading.

MAIN RESULTS

We identified 81 different RCTs. We included 27 of these RCTs, reporting results from 1512 participants and 3230 implants in the review. We compared 38 different implant types with a follow-up ranging from one to 10 years. All implants were made of commercially pure titanium or its alloys, and had different shapes and surface preparations. We judged two trials to be at low risk of bias, 10 to be at unclear risk of bias and 15 to be at high risk of bias. On a 'per participant' rather than 'per implant' basis, we found no significant differences between various implant types for implant failures. The only observed statistically significant difference for the primary objective regarded more peri-implant bone loss at Nobel Speedy Groovy implants when compared with NobelActive implants (MD -0.59 mm; 95% CI -0.74 to -0.44, different implant shapes). The only observed statistically significant difference for the secondary objective was that implants with turned (smoother) surfaces had a 20% reduction in risk to be affected by peri-implantitis than implants with rough surfaces three years after loading (RR 0.80; 95% CI 0.67 to 0.96). There was a tendency for implants with turned surfaces to fail early more often than implants with roughened surfaces.

AUTHORS' CONCLUSIONS

Based on the results of the included RCTs, we found no evidence showing that any particular type of dental implant had superior long-term success. There was limited evidence showing that implants with relatively smooth (turned) surfaces were less prone to lose bone due to chronic infection (peri-implantitis) than implants with much rougher surfaces (titanium-plasma-sprayed). These findings were based on several RCTs, often at high risk of bias, with few participants and relatively short follow-up periods.

Flapless dental implant surgery: a retrospective study of 1,241 consecutive implants

PURPOSE

The purpose of this study was to identify retrospectively the predictors of implant survival when the flapless protocol was used in two private dental practices.

MATERIALS AND METHODS

The collected data were initially computer searched to identify the patients; later, a hand search of patient records was carried out to identify all flapless implants consecutively inserted over the last 10 years. The demographic information gathered on statistical predictors included age, sex, periodontal and peri-implantitis status, smoking, details of implants inserted, implant locations, placement time after extraction, use of simultaneous guided hard and soft tissue regeneration procedures, loading protocols, type of prosthesis, and treatment outcomes (implant survival and complications). Excluded were any implants that required flaps or simultaneous guided hard and soft tissue regeneration procedures, and implants narrower than 3.25 mm.

RESULTS

A total of 1,241 implants had been placed in 472 patients. Life table analysis indicated cumulative 5-year and 10-year implant survival rates of 97.9% and 96.5%, respectively. Most of the failed implants occurred in the posterior maxilla (54%) in type 4 bone (74.0%), and 55.0% of failed implants had been placed in smokers.

CONCLUSION

Flapless dental implant surgery can yield an implant survival rate comparable to that reported in other studies using traditional flap techniques.

Immediate provisionalization of dental implants placed in healed alveolar ridges and extraction sockets: a 5-year prospective evaluation

PURPOSE

This 5-year prospective multicenter study compared implant survival and success, peri-implant health and soft tissue responses, crestal bone level stability, and complication rates following immediate loading of single OsseoSpeed implants placed in anterior maxillary healed ridges or extraction sockets.

MATERIALS AND METHODS

Individuals requiring anterior tooth replacement with single implants were treated and immediately provisionalized. Definitive all-ceramic crowns were placed at 12 weeks. Implant survival, bone levels, soft tissue levels, and peri-implant health were monitored for 5 years.

RESULTS

One hundred thirteen patients received implants in fresh sockets (55) and healed ridges (58). After 5 years, 45 and 49 patients remained for evaluation, respectively. During the first year, three implants failed in the extraction socket group (94.6% survival) and one implant failed in the healed ridge group (98.3% survival); this difference was not significant. No further implant failures were recorded. After 5 years, the interproximal crestal bone levels were located a mean of 0.43 ± 0.63 mm and 0.38 ± 0.62 mm from the reference points of implants in sockets and healed ridges (not a significant difference). In both groups, papillae increased over time and peri-implant mucosal zenith positions were stable from the time of definitive crown placement in sockets and healed ridges. Compared to flap surgery for implants in healed ridges, flapless surgery resulted in increased peri-implant mucosal tissue dimension (average, 0.78 ± 1.34 mm vs 0.19 ± 0.79 mm).

CONCLUSION

After 5 years, the bone and soft tissue parameters that characterize implant success and contribute to dental implant esthetics were similar following the immediate provisionalization of implants in sockets and healed ridges. The overall tissue responses and reported implant survival support the immediate provisionalization of dental implants in situations involving healed ridges and, under ideal circumstances, extraction sockets.