Diode laser as an adjunctive treatment for periodontitis: Arandomized controlled trial

OBJECTIVE

The aim of this randomized controlled trial was to assess clinical and patient reported outcomes of subgingival instrumentation (SI) with adjunctive use of diode laser (DL) versus SI alone in the treatment of periodontitis.

METHODS

Participants requiring non-surgical periodontal treatment were randomly allocated into two treatment groups: SI with DL or SI alone. Clinical parameters [full mouth bleeding and plaque scores (FMBS and FMPS), probing pocket depth and clinical attachment level] were recorded at baseline, three and 6 months post-treatment. Visual analogue scale was used to evaluate postoperative participants' perception of pain, swelling, bleeding, bruising and root sensitivity. The impact of periodontal treatment on quality of life was assessed using the General Oral Health Assessment Index (GOHAI) at 6 months.

RESULTS

A total of 22 participants with stage III/IV periodontitis completed the 6-month follow-up. SI with or without DL resulted in statistically significant reduction in FMBS, FMPS, PPDs, and percentage of PPDs of ≥5 mm at 3- and 6-month follow-up visits (p = 0.001 to <0.001). The participants in SI/DL group had a greater reduction in the percentage of deep PPDs (≥5 mm) compared to those receiving SI alone, but statistically significant differences between the two groups were not observed (16.40 ± 9.57 vs. 32.50 ± 38.76 at 3 months and 7.20 ± 6.86 vs. 19.50 ± 35.06 at 6 months). The difference in the mean total GOHAI scores was not statistically significant at 6 months with total GOHAI scores of 7.25 ± 2.45 and 5.40 ± 3.06 for SI and SI/DL groups, respectively.

CONCLUSION

Within the limitations of this study, the use of DL as an adjunct to SI in the treatment of stage III/IV periodontitis did not produce significant additional improvement in clinical parameters or patient reported outcomes in the 6-month observation period.

Systemic azithromycin versus amoxicillin/metronidazole as an adjunct in the treatment of periodontitis: a systematic review and meta-analysis

BACKGROUND

The use of systemic azithromycin (AZT) and amoxicillin/metronidazole (AMX/MTZ) as adjuncts provided additional clinical and microbiological benefits over subgingival instrumentation alone. However, the superiority of one antibiotic regimen over another has not been proven. Therefore, the aim of this systematic review and meta-analyses was to evaluate the clinical efficacy and safety of subgingival instrumentation (SI) in conjunction with the systemic use of AZT or AMX/MTZ for the treatment of periodontitis from current published literature.

METHODS

Electronic databases were searched to identify randomized controlled trials (RCTs), controlled clinical trials, prospective and retrospective human studies that compared the adjunctive use of systemic AZT to AMX/MTZ with SI in the treatment of periodontitis. The eligibility criteria were defined based on the participant (who had periodontitis), intervention (SI with adjunctive use of systemic AZT), comparison (SI with adjunctive use of systemic AMX/MTZ), outcomes (primary outcome: changes in probing pocket). The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analysed using a statistical software program.

RESULTS

Five studies with 151 participants with periodontitis were included in the present review. Of these, 74 participants received adjunctive AZT, while the remaining participants received AMX/MTZ as an adjunct to SI. The adjunctive use of AZT and AMX/MTZ had comparable changes in probing pocket depths at 1-3 months with no statistically significant difference (mean difference (MD) 0.01; 95% CI -0.20 to 0.22; P = 0.94). The adjunctive use of AZT had significantly fewer number of residual sites with probing pocket depths of ≥5 mm at 1-3 months compared to the adjunctive use of AMX/MTZ (MD -3.41; 95% CI -4.73 to -2.10; P < 0.0001). The prevalence rates of adverse events among participants who received AZT and AMX/MTZ were 9.80% and 14.8%, respectively. The meta-analysis showed that the difference between the two groups was not statistically significant (risk ratio 0.69; 95% CI 0.28 to 1.72; P = 0.43).

CONCLUSIONS

Within the limitation of this review, there was no superiority between AZT and AMX/MTZ in terms of mean changes in probing pocket depths, clinical attachment level, bleeding on probing at 1-3 months. AZT seem to be associated with less sites with residual probing pocket depths of ≥5 mm at 1-3 months and fewer adverse events compared with AMX/MTZ. © 2023 Australian Dental Association.

Influence of implant restorative emergence angle and contour on peri-implant marginal bone loss: A systematic review and meta-analysis

BACKGROUND

Implant restorative emergence angle and profile may have a negative impact on peri-implant marginal bone level and may increase the risk of developing peri-implantitis. However, the role of these prosthetic features on peri-implant health is still unclear. The aim of this systematic review and meta-analyses was to evaluate the long-term outcomes of implant restorations with an emergence angle of >30° in comparison to those with ≤30° in terms of changes in peri-implant marginal bone level, periodontal parameters, and prevalence rate of peri-implantitis.

METHODS

Electronic databases were searched to identify observational studies that compared implant restorations with an emergence angle of >30° to those with ≤30°. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool.

RESULTS

Four studies with 912 dental implants in 397 participants were included in the present review. Of these, 455 implants had restorations with an emergence angle of >30°, while the remaining implants had restorative emergence angle of ≤30°. The follow-up time varied between 3.8 and 10.9 years. Implant restorations with an emergence angle of ≤30° were associated with less changes in peri-implant marginal bone level compared to those with emergence angle of >30°. The difference, however, was not statistically significant (mean difference 0.80; 95% confidence interval (CI) -0.13 to 1.72; p = 0.09). In platform-matched implants, the difference between the two groups was statistically significant in favor of implant restorations with emergence angle of ≤30°. In terms of emergence profile, implant restorations with convex profile had significantly higher rate of peri-implantitis (57.8%) compared to implant restorations with concave or straight profile (21.3%) (risk ratio 2.32; 95% CI 1.12-4.82; p = 0.02).

CONCLUSIONS

Within the limitation of this review, implant restorations with an emergence angles of >30° or ≤30° seem to have no significant influence on peri-implant marginal bone level. Platform-matched implants with an emergence angle of ≤30° may have positive effects on the peri-implant marginal bone level changes, but the evidence support is of low to moderate certainty.

Airflow for initial nonsurgical treatment of peri-implantitis: A systematic review and meta-analysis

BACKGROUND

Nonsurgical treatment of peri-implantitis may help in reducing microbial load and inflammatory parameters. The potential clinical benefits of using different treatment approaches, in the initial nonsurgical treatment phase, particularly the airflow, are still not clear. The aim of this systematic review and meta-analyses was to evaluate the outcomes of nonsurgical treatment of peri-implantitis using airflow method in terms of changes in periodontal parameters, peri-implant marginal bone level, postoperative pain/discomfort, and patient satisfaction.

METHODS

Electronic databases were searched to identify randomized controlled trials (RCTs) that compared airflow with mechanical debridement using ultrasonic/curettes. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analyzed using a statistical software program.

RESULTS

A total of 316 studies were identified, of which, five RCTs with 288 dental implants in 174 participants were included. Overall meta-analysis showed more reduction in probing pocket depths at 1-3 months (mean difference [MD] -0.23; 95% confidence interval [CI] -0.50-0.05; p = 0.10) and 6 months (MD -0.04; 95% CI -0.34 to 0.27; p = 0.80) in favor of airflow, but the difference was not statistically significant. The use of airflow was associated with significant reduction in bleeding on probing and increase in peri-implant mucosal recession. The differences in plaque score, peri-implant marginal bone level changes, and patient reported outcomes between airflow and mechanical debridement were not statistically significant.

CONCLUSIONS

The short-term clinical and radiographic outcomes following nonsurgical treatment of peri-implantitis using airflow or mechanical debridement were comparable. The airflow has short-term positive effects on reducing bleeding on probing. Further evidence from RCTs are still required to substantiate the current findings.

The influence of insertion torque values on the failure and complication rates of dental implants: A systematic review and meta-analysis

BACKGROUND

The influence of using different insertion torque values on clinical and radiographic outcomes of implant therapy is unclear in the current literature. The aim of this systematic review and meta-analysis was to evaluate the implant outcomes and complications rates using high insertion torque values compared with those using regular insertion torque value levels.

METHODS

Randomized controlled trials (RCTs), nonrandomized controlled clinical trials (NRCCTs), prospective and retrospective cohorts were searched for in electronic databases and complemented by hand searching relevant dental journals. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool for randomized and nonrandomized studies. Data were analyzed using a statistical software.

RESULTS

A total of 718 studies were identified, of which, nine studies were included with 1229 dental implants in 684 participants. The meta-analysis of RCTs showed that the overall implant failure rate was not notably in favor of any insertion torque value and the difference between the two groups was not statistically significant (risk ratio 0.85; 95% confidence interval 0.07-10.52; P = 0.90). None of the RCTs was registered. The secondary analyses of non-RCTs did not either show any statistically significant difference. Overall meta-analysis did not show any significant differences in peri-implant marginal bone loss or biological/technical complications between high (≥50 Ncm) and regular insertion torque (<50 Ncm).

CONCLUSIONS

There is insufficient evidence to support the use of high or regular insertion torque even with immediate implant restoration/loading. The short-term implant failure rates, changes in marginal bone level and complication rates were comparable when high or regular insertion torques were used for implant placement. The wide confidence interval indicated that results cannot be interpreted with clinically meaningful benefit for using either high or regular insertion torque.

Resonance Frequency Analysis in Assessing Implant Stability: A Retrospective Analysis

PURPOSE

To retrospectively assess implant stability quotient (ISQ) values in patients who were followed up between 1998 and 2014 and to evaluate any correlations between ISQ and clinical parameters, such as change in marginal bone level (MBL).

MATERIALS AND METHODS

A total of 173 participants (65 men and 108 women; age range 21 to 85 years) and 383 implants were included. Implant location, MBL, and ISQ were recorded at surgery and at various recall times for statistical analysis. Mixed-model analysis was applied to evaluate the impact of clinical and demographic variables (time, implant location, patient gender) on ISQ and the correlation between ISQ and MBL. The level of significance was set at P < .05.

RESULTS

Of the 21 failed implants, 20 failed within 1 year of functional loading, resulting in a 10-year cumulative implant survival estimate of 95%. The failed implants had lower ISQs at surgery (52.3 ± 7.03) and baseline (52.5 ± 4.20) when compared to surviving implants (63.0 ± 10.74 at surgery and 62.3 ± 8.30 at baseline), and the difference was statistically significant at surgery (P < .05). The mean ISQs generally increased over time, but there were various patterns of changes between implants when grouped according to patient gender and implant location. There was no statistically significant correlation between the changes in ISQ and MBL (P = .211), despite an inverse relationship.

CONCLUSION

Low initial ISQ values may help to identify implants at higher risk of failure. There may be various patterns of change over time in addition to an overall increase in ISQ values. Both similar and contradictory findings were found when compared to earlier literature, and a correlation between resonance frequency analysis and MBL change could not be identified. Despite limitations, the present study provides an overview of the clinical performance of RFA based on long-term clinical data.

Titanium particles: An emerging risk factor for peri-implant bone loss

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Titanium wear particles were identified in peri-implantitis tissues.

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Overexpressed cytokine levels for RANKL and high levels of the other inflammatory cytokines (TGF-β1, IL-33 and CD68) were observed.

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A causal relationship between the presence of particles and peri-implantitis cannot be confirmed.

Objective

To investigate the presence of titanium particles in peri-implant tissues in cases diagnosed with peri-implantitis, and to identify immunological reactions that these particles may elicit.

Methods

Ten peri-implant tissue biopsies of patients diagnosed clinically and radiographically with peri-implantitis were obtained from the archives of Oral Pathology Centre, University of Otago. The inclusion criteria involves: bleeding on probing, ≥6 mm probing depth and ≥3 mm radiographic bone loss around the dental implant. Peri-implant tissue samples were evaluated using scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS) to identify of sites with/without titanium particles. Antibodies against human transforming growth factor beta 1 (TGF-β1), receptor activator of nuclear factor kappa-B ligand (RANKL), interleukin 33 (IL-33) and cluster of differentiation 68 (CD68) were used to stain the specimens. ImageJ software was used to standardise the sampling area, compare and characterise the inflammatory infiltrate in tissues with/without titanium particles. Inflammatory cytokines positivity was assessed using the immunoreactive scores (IRSs).

Results

Light microscopy and SEM-EDS analysis identified titanium wear particles in 90% of the tissue samples, associated with a mixed chronic inflammatory infiltrate. Quantification analysis of RANKL revealed significantly higher IRS and intensity scores (p < 0.05) in areas containing titanium. High intensity, proportion and IRSs of TGF-β1 and IL-33 were observed in areas with titanium. CD68 had higher IRSs in the absence of titanium particles.

Conclusions

Significant overexpression of the cytokine RANKL was observed, with a trend for over-expression of IL-33 and TGF-B1 in areas with titanium. Further studies with large sample size and appropriate control group for quantification analysis is needed to confirm the role of titanium particles in initiating bone loss.

Predicting peri-implant disease: Chi-square automatic interaction detection (CHAID) decision tree analysis of risk indicators

BACKGROUND

Further validation of the risk indicators / predictors for peri-implant diseases is required to allow clinicians and patients to make informed decisions and optimize dental implant treatment outcomes. The aim of this study was to build prediction models, using Chi-square automatic interaction detection (CHAID) analysis, to determine which systemic-, patient-, implant-, site-, surgical- and prostheses-related risk indicators had more impact on the onset of peri-implant diseases.

METHODS

A retrospective analysis of 200 patients who received implant-supported prostheses between 1998 and 2011 was conducted to evaluate the prevalences and risk indicators for peri-implant mucositis and peri-implantitis. The data were further analyzed using CHAID to produce two predictive models.

RESULTS

The prevalence of peri-implant mucositis was 20.2% and 10.2% for patients and implants, respectively, while the prevalence of peri-implantitis was 10.1% at the patient level and 5.4% at the implant level. CHAID decision tree analysis identified three predictors (history of treated periodontitis, absence of regular supportive peri-implant maintenance, and use of bone graft) for peri-implant mucositis and three predictors (smoking, absence of regular supportive peri-implant maintenance, and placement of ≥2 implants) for peri-implantitis.

CONCLUSIONS

Within the limitations of this study, CHAID decision tree analysis identified the most plausible risk indicators and provided two predictive models for use in a particular university setting that would allow early detection and ensure appropriate care and maintenance of patients at high risk of peri-implant diseases.

Piezoelectric versus conventional implant site preparation: A systematic review and meta-analysis

BACKGROUND

The use of a piezoelectric device (PED) for implant site preparation (ISP) has been introduced to overcome the limitations of using conventional drills (CDs). With little and inconsistent information in the literature regarding their efficiency for preparing implant osteotomies, the objective of this systematic review was to compare the use of CDs to PEDs for ISP with regard to implant stability values, marginal bone level changes, operating time, and dental implant failure rate.

METHODS

The systematic review was prepared according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The literature was searched for studies that assessed the use of CDs and PEDs for ISP. The Cochrane Collaboration risk of bias tool was used to evaluate the selected studies and meta-analyses were performed using statistical software.

RESULTS

A total of 755 citations were identified. Of these, 4 studies with 178 implant osteotomies in 80 participants were included. The pooled estimates for the implant stability showed significant differences between the 2 surgical techniques in favor of PEDs at baseline, 8 and 12 weeks. A statistically significant difference in the operating time was also shown between the 2 techniques with more time required using PED. The differences in marginal bone level changes or implant failure rate were not statistically significant.

CONCLUSIONS

With the limitations of this review in mind, PEDs appear to be a viable alternative to traditional drilling techniques for ISP. With the exception of prolonged operating time associated with the use of PEDs, both techniques were comparable in terms of the marginal bone level changes and the risk of implant failure. The favorable influence of the implant stability pattern related to the use of PEDs on the predictability of immediate and early loading protocols need to be confirmed in future studies.

The One Abutment-One Time Protocol: A Systematic Review and Meta-Analysis

BACKGROUND

The use of definitive abutments (DAs) at time of implant placement has been introduced to overcome limitations of dis/reconnection of healing/provisional abutments (PAs). With little and inconsistent information in the literature regarding the effectiveness of using DAs, the aim of this systematic review is to examine marginal bone and soft tissue level changes, technical and biologic complications, and implant failure rate associated with use of DAs and PAs.

METHODS

This systematic review was prepared according to guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and online trial registers were searched for studies comparing use of DAs and PAs. The Cochrane Collaboration risk of bias tool was used to assess selected studies, and meta-analyses were performed using statistical software.

RESULTS

A total of 1,124 citations were identified. Of these, seven trials with 363 dental implants in 262 participants were included in the analysis. Pooled estimates for marginal bone level changes showed significant differences between the two prosthetic techniques in favor of using DAs. No significant differences were found in soft tissue level changes, technical and biologic complications, or implant failure rate.

CONCLUSIONS

Within the limitations of this review, DAs appear to be a viable alternative to PAs at time of implant placement. However, favorable changes in peri-implant marginal bone level associated with use of DAs should be viewed with caution as its clinical significance is still uncertain.

Piezoelectric surgery vs rotary instruments for lateral maxillary sinus floor elevation: a systematic review and meta-analysis of intra- and postoperative complications

PURPOSE

Lateral maxillary sinus floor elevation (LMSFE) is a predictable preprosthetic surgical procedure that is used to overcome the limitations of the atrophied alveolar ridge for the placement of oral implants. Techniques using piezoelectric devices (PEDs) and conventional rotary instruments have been described for LMSFE in the literature, with little information regarding their efficiency in terms of membrane perforation, operating time, and implant outcomes. The aim of this systematic review was to examine the intra- and postoperative events associated with the use of PEDs and conventional rotary instruments for LMSFE.

MATERIALS AND METHODS

This systematic review was prepared according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature was searched for studies comparing the use of PEDs with conventional rotary instruments for LMSFE. The Cochrane Collaboration risk of bias tool was used to assess the studies selected, and meta-analyses were performed using statistical software.

RESULTS

A total of 124 citations were identified. Of these, four studies with 178 LMSFEs in 120 participants were included. The pooled estimates for the risk of sinus membrane perforation did not show any significant difference between the two surgical techniques (risk ratio, 0.87; 95% confidence interval, 0.40-1.91; P = .73). Similarly, no significant difference in implant failure was found after 1 year of functional loading. The overall meta-analysis showed a statistically significant difference in the operating time between the two techniques with more time required for PED.

CONCLUSION

The intra- and postoperative events associated with the use of PEDs and conventional rotary instruments for LMSFE are comparable.

Xenogeneic collagen matrix for periodontal plastic surgery procedures: a systematic review and meta-analysis

Several clinical trials describe the effectiveness of xenogeneic collagen matrix (XCM) as an alternative option to surgical mucogingival procedures for the treatment of marginal tissue recession and augmentation of insufficient zones of keratinized tissue (KT). The aim of this systematic review and meta-analysis was to evaluate the clinical and patient-centred outcomes of XCM compared to other mucogingival procedures. Applying guidelines of the Preferred Reporting Items for Systematic Reviews and Meta analyses statement, randomized controlled trials were searched for in electronic databases and complemented by hand searching. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool and data were analysed using statistical software. A total of 645 studies were identified, of which, six trials were included with 487 mucogingival defects in 170 participants. Overall meta-analysis showed that connective tissue graft (CTG) in conjunction with the coronally advanced flap (CAF) had a significantly higher percentage of complete/mean root coverage and mean recession reduction than XCM. Insufficient evidence was found to determine any significant differences in width of KT between XCM and CTG. The XCM had a significantly higher mean root coverage, recession reduction and gain in KT compared to CAF alone. No significant differences in patient's aesthetic satisfaction were found between XCM and CTG, except for postoperative morbidity in favour of XCM. Operating time was significantly reduced with the use of XCM compared with CTG but not with CAF alone. There is no evidence to demonstrate the effectiveness of XCM in achieving greater root coverage, recession reduction and gain in KT compared to CTG plus CAF. Superior short-term results in treating root coverage compared with CAF alone are possible. There is limited evidence that XCM may improve aesthetic satisfaction, reduce postoperative morbidity and shorten the operating time. Further long-term randomized controlled trials are required to endorse the supposed advantages of XCM.

The effect of piezoelectric ultrasonic instrumentation on titanium discs: a microscopy and trace elemental analysis in vitro study

AIM

To evaluate in vitro topographical and composition changes by piezoelectric ultrasonic instrumentation with metallic and plastic tips on machined and moderately roughened titanium surfaces.

METHODS

Twenty machined and moderately roughened laser-marked titanium discs were ultrasonically instrumented with metallic and plastic tips. Surface instrumentation was carried out with controlled pressure for 20 and 30 seconds at two power settings. For each time and power setting, instrumentation was repeated four times with one instrumentation per disc quadrant. Surface topography analysis was performed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Surface roughness measurements were compared between instrumented and non-instrumented surfaces. Surface element composition and rinsing solutions were evaluated using energy-dispersive spectroscopy (EDS) and trace elemental analysis using inductively coupled plasma mass spectrometry (ICPMS), respectively.

RESULTS

SEM photomicrographs and CLSM 3D surface plot images of instrumented machined and moderately roughened surfaces demonstrated severe surface topographical alterations with metallic tips and mild to moderate changes for plastic tip instrumented sites. ICPMS analysis of the rinsing solutions identified titanium and other metal traces with the use of metallic tips, and mainly titanium and carbon when plastic tips were used. Surface EDS analysis showed elemental traces of the ultrasonic tips.

CONCLUSION

Ultrasonic instrumentation with metallic or plastic tips created surface topographical and compositional changes. Different changes in surface topography were noted between the surfaces, as the roughness of the machined surfaces increased while the extent of roughness of the moderately roughened surfaces decreased. The clinical relevance of these changes is yet to be determined.

Peri-implantitis diagnosis and treatment by New Zealand periodontists and oral maxillofacial surgeons

OBJECTIVES

This study aimed to investigate the understanding, diagnosis and management of peri-implantitis by New Zealand periodontists and oral maxillofacial surgeons (OMFS).

DESIGN

Telephone interviews (in combination with a postal and electronic survey) were conducted of all 25 periodontists and 32 OMFS listed as specialists on the New Zealand Dental Register. A seven item multi-choice and short answer questionnaire was used to investigate: their definition of peri-implantitis; the number of annual referrals received in their practice for this condition; their diagnostic, preventive and treatment strategies for peri-implantitis; and their perception of the role of general dental practitioners in its management.

RESULTS

The participation rate was 84.6%. Most respondents defined peri-implantitis as a disease of multifactorial aetiology that leads to destruction of the bone supporting an implant. The average number of cases seen annually differed between periodontists (11 cases/year) and OMFS (4 cases/year). The criteria used by the respondents to diagnose peri-implantitis included increased probing depths and radiographic evidence of bone loss. Each type of specialist used mechanical debridement for treatment, but a higher proportion of OMFS performed surgical procedures as treatment. The prevention strategies used smoking cessation advice and ensuring good plaque control. All respondents agreed that peri-implantitis is an important disease that can lead to implant failure, and all acknowledged the role of general dental practitioners in diagnosis, referral for treatment and long-term implant maintenance.

CONCLUSION

The definition, diagnostic criteria and management strategies used by New Zealand specialists are generally consistent with those found in the literature. No evidence-based, gold standard treatment protocol for peri-implantitis has been identified in the literature, and New Zealand specialists use a range of treatment modalities.

Effect of a cordless retraction paste on titanium surface: a topographic, chemical and biocompatibility evaluation

Good exposure of the preparation margins and haemostasis in the sulcular gingiva are necessary for accurate impressions to produce precise restorations. The use of cordless retraction paste material in implant dentistry is a relatively novel application. However, few studies have been conducted on the use of retraction pastes and their possible interaction with implant surfaces. Recent literature has described remnants on titanium implant surfaces and expressed the need for an assessment of the biocompatibility of the exposed surface (Chang et al.). This in vitro study evaluated the effect of a cordless gingival retraction paste on sterile titanium disks. Surface chemistry was determined using energy-dispersive X-ray spectroscopy (EDS), and further investigated using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). After exposure to retraction paste, surface chemistry alterations were identified. A fibroblast cell line (L929) was exposed to the disks and the live/dead viability/cytotoxicity assay was used to determine any effects on the proliferation and health of cells. The disks exposed to the retraction paste showed fewer dead cells compared to the unexposed disks. This was statistically significant.

Multicentre prospective evaluation of implant-assisted mandibular bilateral distal extension removable partial dentures: patient satisfaction

OBJECTIVE

To compare the levels of patient satisfaction with either conventional mandibular bilateral distal extension partial dentures or those assisted by bilateral distal implants.

MATERIALS AND METHODS

Forty-eight participants who were dissatisfied with their existing conventional mandibular distal extension dentures opposing complete maxillary dentures were selected for a multicentre prospective study in New Zealand, Colombia and the Netherlands. A control group of 12 participants in New Zealand received conventional mandibular partial dentures. Three test groups involving 36 participants in New Zealand (12), Colombia (12) and the Netherlands (12) received bilateral distal implants in the second molar regions. After conventional loading, the test group participants initially had healing caps placed on the distal implants providing support only, followed after approximately 6 months by ball abutments (retentive anchors) for support and retention. Patient outcomes were determined with questionnaires completed at specific stages of the study for up to 3 years.

RESULTS

Visual analogue scale, Likert and oral health impact questionnaires before and after treatment indicated improved results. There were significantly improved parameters of overall satisfaction, stability, chewing and appearance after 3 years (P < 0.05). There were also improvements on stability, chewing and overall satisfaction. Speech also improved, but not significantly. Ball abutments (retentive anchors) on the distal implants, as opposed to healing caps improved patient satisfaction for stability, chewing and overall satisfaction. Changing to ball abutments (retentive anchors) revealed significant improvement by participant response when evaluating parameters of stability, chewing and overall satisfaction (P < 0.05).

CONCLUSION

Mandibular implant-assisted removable partial dentures are a preferable treatment option for patients with complaints about their conventional distal extension partial dentures.

Marginal bone loss with mandibular two-implant overdentures using different loading protocols and attachment systems: 10-year outcomes

PURPOSE

The aim of this study was to evaluate long-term marginal bone levels for two unsplinted implants supporting mandibular overdentures using conventional and early loading protocols with different implant surfaces and attachment systems.

MATERIALS AND METHODS

A cohort of 106 edentulous participants (mean age: 65 years) was treated with mandibular two-implant overdentures opposing complete maxillary dentures. Participants were randomly allocated into three loading protocol groups using four implant systems; single-stage surgery was performed for all participants, followed by an unsplinted prosthesis using six different attachment systems. Standardized intraoral radiographs taken at baseline (loading) and over 10 years appraised marginal bone levels mesially and distally from reference points under magnification. Three calibrated examiners repeated measurements, diminishing intra- and interobserver variability. Progressive attrition of participants occurred as a result of deaths, dropouts, and emigration. Seventy-nine participants (74.5%, mean age: 72 years) were available at the 10-year recall. Differences in bone loss among different loading protocols, implant surfaces, and attachment systems were tested using chi-square and one-way analysis of variance tests.

RESULTS

Minimal, time-dependent, long-term marginal bone loss occurred with all loading protocols. Annual marginal bone loss progressed at low levels after the first year with episodes of bone loss and gain. There was stability in marginal bone levels over the long term, with the majority of remodeling occurring during the first year of function. Roughened implant surfaces may be beneficial during the early remodeling period. The amount of marginal bone loss in the first year of loading differed significantly by loading protocol and implant surface, whereas attachment system had a minor influence. Differences were not reflected in the success rates calculated using standard criteria. The remaining participants at 10 years were classified as successful related to the criterion of marginal bone loss, irrespective of the determining criteria for success.

CONCLUSIONS

Either a 2- , 6-, or 12-week loading protocol for mandibular two-implant overdentures is possible in the long term, irrespective of the attachment system used. Minimal marginal bone loss may be attributed primarily to mandibular basal bone remaining from long-term edentulism. Revision of the current implant success criteria to offer a stricter limit is desirable.

Age and oral health: current considerations

Dental plaque is still considered the main etiological factor for periodontal diseases. Our understanding of periodontal disease has advanced from the previous concepts where gingivitis slowly progressed to periodontitis to a more complex scenario that correlates several risk factors in the pathogenesis of periodontal disease. Among these factors, age has been associated with increased rates of periodontal disease as the population gets older. Although the loss of alveolar bone and periodontal attachment is common in the elderly population, and there is evident age-related changes in the periodontium, severe periodontitis is not a natural consequence of ageing. The importance of identifying the risk factors that participate in the pathogenesis of periodontal disease at an early phase, both of the individual and the disease, as well as evaluating the capacity of the individual to control dental plaque will enable the implementation of an adequate preventive program, where the needs and limitations of the individual are considered to specifically tailor the oral hygiene procedures and the mouthwashes to be used.

Compliance & dexterity, factors to consider in home care and maintenance procedures

Mechanical plaque control appears to be the primary means of controlling supragingival dental plaque build-up. Although daily oral hygiene practices and periodic professional care are considered the basis for any program aimed at the prevention and treatment of oral diseases, these procedures are technically demanding, time consuming and can be affected by the compliance and manual dexterity of the patient. Individual skills and acquired behavior patterns determine effectiveness of a preventive program and oral hygiene practice. Successful preventive programs and home care procedures clearly depend on the interaction and commitment between the dental professional and the patient. Identifying the capacity of the individual to comply with the professional recommendations and evaluating the dexterity of the patient to remove supragingival dental plaque will permit the implementation of an adequate preventive program and can help on the selection of adjunctive antimicrobial agents and devices needed to reach an effective oral care routine.

One-Stage Surgery and Early Loading of Three Implants for Maxillary Overdentures: A 1-Year Report

BACKGROUND

Maxillary implant overdentures opposing mandibular two-implant overdentures are an underused treatment option for edentulous patients. Fewer implants, simple surgery, and short healing periods may increase patients' acceptance of this treatment concept.

PURPOSE

To determine implant success, after overdenture loading, of three narrow-diameter roughened-surface implants placed in edentulous maxillas, using a one-stage surgical procedure, a 12-week healing period, and opposing mandibular two-implant overdentures.

MATERIALS AND METHODS

Forty edentulous participants with mandibular two-implant overdentures were allocated to two groups with similar implant systems. Each group had three narrow-diameter roughened-surface implants placed into their edentulous maxillas in a one-stage surgical procedure. Standardized intraoral radiography and implant stability tests were performed sequentially at surgery, at 12 weeks (prior to loading), and at 64 weeks (after 1 year of loading with maxillary overdentures).

RESULTS

One hundred seventeen implants were placed in 39 participants. After 1 year of loading, 15 implants had failed in 11 patients, 4 implants have been "put to sleep" in 3 patients, and 1 patient has died. Data on marginal bone loss and resonance frequency analysis showed no significant differences between the implant systems. The mean marginal bone loss was 1.30 mm (+/- 0.44 mm) from surgery to 12 weeks and 0.32 mm (+/- 0.48 mm) between 12 and 64 weeks with loading. The mean implant stability quotient and resonance frequency values showed a statistically significant improvement over time, at 56.05 (5,891 Hz), 57.54 (5,981 Hz), and 60.88 (6,167 Hz) at surgery, 12 weeks, and 64 weeks, respectively. The overall success rate for all implants combined was 81%, and the cumulative survival rate was 84.61%.

CONCLUSION

In patients with mandibular two-implant overdentures, three narrow-diameter roughened-surface implants can be placed in the edentulous maxilla, using a one-stage surgical procedure, and can be loaded within 12 weeks with overdentures for 1 year.

Early Functional Loading of Unsplinted Roughened Surface Implants with Mandibular Overdentures 2 Weeks after Surgery

BACKGROUND

Before early functional loading of unsplinted implants with mandibular overdentures can become widespread, more clinical studies are needed to investigate the success of the approach.

PURPOSE

To evaluate the success rates of two types of roughened titanium surface implants with early 2-week functional loading of paired mandibular interforaminal implants with overdentures.

MATERIALS AND METHODS

Random allocation divided 24 strictly selected edentulous participants into two groups, with each group to receive a different implant system (ITI Dental Implant System, Straumann AG, Waldenburg, Switzerland; or Southern Implant System, Southern Implants, Irene, South Africa). Two implants were placed in the anterior mandible of all participants using one-stage standardized surgical procedures. Previously constructed conventional mandibular dentures (opposing maxillary complete dentures) were temporarily relined and worn by the participants for the first 2 weeks; participants used a soft diet. Two weeks after implant surgery and following some mucosal healing, the mandibular dentures had the tissue conditioner removed and the appropriate matrices included for an unsplinted prosthodontic design.

RESULTS

No implant from either group was lost. Resonance frequency analysis (RFA) indicated higher primary stability at surgery for the Southern group than for the ITI group, with a statistically significant difference between the groups throughout the study period. The drop in RF values between surgery and 6 weeks was significant and was greater for the Southern group. RFA also indicated stabilized osseointegration between 6 to 12 and 12 to 52 weeks, with no participant showing any decrease in those values over time. Participants with type 3 bone showed a significant improvement in RF values between 12 and 52 weeks, eventually matching those of participants with type 2 bone. There were no significant differences in marginal bone loss, periimplant parameters, or prosthodontic maintenance between the groups over the study period.

CONCLUSIONS

Using only strict patient selection criteria, 1-year follow-up data indicate that early functional loading of ITI and Southern implants with mandibular two-implant overdentures is possible as early as 2 weeks after implant surgery.

Conventional and early loading of unsplinted ITI implants supporting mandibular overdentures

The aim of this study was to compare the success rates after 1 and 2 years of conventionally and early loaded pairs of unsplinted ITI implants supporting mandibular overdentures in edentulous patients. Twenty-four participants (age range 55-80 years) were randomly allocated with maximum concealment to two treatment groups. In the first group, the implants were allowed to heal for 12 weeks before being functionally loaded (control) and the second group had 6 weeks of healing with identical loading. All participants had new conventional complete maxillary and mandibular dentures prior to the study. Two sandblasted large-grit acid-etched (SLA) surface ITI implants were placed in the mandibular interforaminal area, following a standardized nonsubmerged surgical protocol. After 6 or 12 weeks of healing, matrices were processed into the fitting surface of the pre-existing mandibular dentures and the implants loaded. Implant success was determined using mobility tests and radiographs taken at baseline and 52 and 104 weeks after surgery. Clinical peri-implant parameters were also documented. Results showed all implants successfully osseointegrated, according to accepted criteria, after 2 years. Mean loss of crestal bone height after 1 year was 0.35 +/- 0.22 mm (control) vs. 0.27 +/- 0.18 mm (test). After 2 years this reduced to 0.09 +/- 0.06 mm (control) vs. 0.12 +/- 0.17 mm (test). The mean Periotest value after 1 year was -4.9 (control) vs.-3.78 (test). After 2 years, the mean resonance frequency value for the control implants was 6797 Hz [mean implant stability quotient (ISQ) = 64.77] and for the test implants 6670 Hz (mean ISQ = 62.0). Shortened loading periods for these ITI implants did not cause any statistically significant differences in osseointegration or peri-implant parameters. We conclude that pairs of unsplinted SLA-surface ITI implants can be successfully loaded with mandibular overdentures 6 weeks after surgery.

Early loading of unsplinted implants supporting mandibular overdentures using a one-stage operative procedure with two different implant systems: a 2-year report

BACKGROUND

Step-wise reduction in loading protocols is necessary to evaluate early loading of implants with mandibular overdentures.

PURPOSE

To compare the success rates of two different dental implant systems following conventional or early loading protocols in patients being rehabilitated with mandibular overdentures.

MATERIALS AND METHODS

Forty-eight edentulous participants were randomly allocated to two different implant systems: one with a machined titanium implant surface (Sterioss, Nobel Biocare, Yorba Linda, California, USA) and the other with a roughened titanium surface (Southern Implants, Irene, South Africa). For each system, the participants were further divided into control groups, in whom mandibular implant overdentures and their respective matrices were inserted following a standard 12-week healing period, and test groups, in whom a 6-week healing period was followed prior to identical loading. Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all participants, using a standardized one-stage surgical procedure. Mobility tests and marginal bone levels, as well as peri-implant parameters, were evaluated at each baseline and 52 and 104 weeks after surgery.

RESULTS

There was no statistically significant difference in the success rates of the two systems in either control or test groups. At the 2-year evaluation, a success rate was found of 87.5% and 70.8% for the control and test Sterioss groups, respectively, and 83.3% and 100% for the control and test Southern Implants groups were observed. For the Sterioss groups, eight implants were lost at an early stage: seven in the test group and one in the control group. For the Southern Implants control and test groups, no failures were seen at any time interval. There were no significant differences in marginal bone loss, Periotest values, and peri-implant parameters between implant systems or between any of the control or test groups.

CONCLUSIONS

Early loading, with step-wise reductions in loading protocols, of unsplinted machined Sterioss and roughened Southern Implants fixtures with mandibular overdentures is possible for up to 2 years.

One-stage operative procedure using two different implant systems: a prospective study on implant overdentures in the edentulous mandible

BACKGROUND

Evidence-based reports are needed to support the application of a one-stage surgical protocol for unsplinted implants supporting mandibular overdentures.

PURPOSE

To examine the feasibility and success of using two different dental implant systems (originally designed for two-stage operative technique) using a one-stage operative procedure in patients being rehabilitated with implant mandibular overdentures.

MATERIALS AND METHODS

The study sample involved 24 edentulous subjects (aged 55-80 yr) randomly allocated to two different implant systems, one with a machined titanium implant surface (Steri-Oss, Nobel Biocare, Göteborg, Sweden) and the other with a roughened titanium surface (Southern Implants, Ltd., Irene, South Africa). Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all patients, using a standardized one-stage surgical and prosthodontic procedure. Primary stability and bicortical anchorage of the implants was mandatory before healing abutments were connected at the time of implant placement. Implant overdentures and their respective matrices were inserted following a standard 12-week healing period. Data relating to mobility tests, radiographs, and peri-implant parameters were documented at 12, 16, and 52 weeks after surgery.

RESULTS

A success rate of 95.8% for the Steri-Oss and 100% for the Southern Implants was found, without any statistically significant differences in the marginal bone loss. Significant changes in Periotest values were observed for both types between 12 and 52 weeks (p < .001). Minor changes were observed in the peri-implant parameters evaluated.

CONCLUSIONS

These preliminary findings show a successful application of this one-stage approach for unsplinted implants supporting mandibular overdentures with Steri-Oss and Southern Implant Systems.

Relative effectiveness of powered and manual toothbrushes in elderly patients with implant-supported mandibular overdentures

AIM

The aim of this study was to compare the clinical effectiveness of a powered toothbrush (Braun Oral-B Plaque Remover 3-D) and a manual soft toothbrush (Oral-B Squish-grip brush) for the control of supragingival plaque and soft tissue inflammation around implants supporting mandibular overdentures.

MATERIAL AND METHODS

The study sample involved 40 edentulous subjects, aged 55-80 years, having 2 unsplinted mandibular implants supporting a complete removable overdenture opposed by a maxillary complete denture. In this single-blinded, randomised, cross-over clinical trial, two 6-week experimental phases were separated by a 2-week wash-out period. 2 weeks prior to each experimental phase (pre-entry visits), implant abutments were polished to remove all plaque and a standardised instruction in the use of the toothbrush was given. Modified plaque and bleeding indices were recorded at the start and end of each experimental period. Mean index scores at each phase were analysed using paired t-test, and the mean number of sites showing a change in plaque or mucositis were compared using the Mann-Whitney U-test. Combined data from 2 different implant systems were considered after controlling for implant type.

RESULTS

Only minor changes in plaque and bleeding scores were observed following the two test periods. There were no statistically significant differences between the manual and powered toothbrushes.

CONCLUSION

Manual and powered brushes were found to be of comparable efficacy with regard to improvement in peri-implant bleeding and plaque indices.

One-year prospective evaluation of the early loading of unsplinted conical Brånemark fixtures with mandibular overdentures immediately following surgery

BACKGROUND

Prospective evaluation of the early loading of unsplinted Brånemark implants with mandibular overdentures opposing conventional dentures is not evident in the implant-related literature.

PURPOSE

To clinically evaluate progressive and early loading of 20 unsplinted conical Brånemark implants in edentulous mandibles with overdentures.

MATERIALS AND METHODS

Ten edentulous patients all had two conical Brånemark implants placed in the anterior mandible with mandatory primary stability with bicortical anchorage. Ball abutment connection was performed simultaneously. Previously constructed conventional mandibular dentures were temporarily relined with tissue conditioner postoperatively and worn with moderation for the first 2 weeks to allow progressive loading. Early loading of the implants followed after 2 weeks, with inclusion of the respective matrices in the mandibular dentures, using a definitive reline procedure.

RESULTS

All patients successfully functioned with their mandibular implant overdentures from 2 to 52 weeks postoperatively. Mean marginal bone loss was within established criteria for success: 0.22 mm (SD = 0.48 mm) mesially and 0.30 mm (SD = 0.39 mm) distally on the conical implants. Mobility tests using the Periotest instrument became more negative, although not at statistically significant levels. Difficulties in the management of the peri-implant mucosa between surgery and loading at 2 weeks were observed in 40% of the patients.

CONCLUSIONS

These preliminary 1-year results show that successful early loading of unsplinted conical Brånemark implants with mandibular overdentures is possible.

Inter-abutment and peri-abutment mucosal enlargement with mandibular implant overdentures

A variety of terms have been used to describe changes in the oral mucosa around abutments underneath fixed and removable implant prostheses such as mucosal inflammation, peri-implant mucosal hyperplasia, gingival hyperplasia, hyperplastic tissue, mucosal proliferation, proliferative gingivitis and peri-implant mucositis. Although such terms have become part of the evidence-based literature, there is no histological evidence to support the descriptive terminology used by authors. The use of the alternative term mucosal enlargement for clinical observations underneath mandibular implant overdentures is proposed. Prospective and retrospective reports have failed to use similar criteria to measure periodontal parameters in relation to these mucosal changes, both in keratinized or non-keratinized tissues. Therapeutic remedies for mucosal enlargement are dictated by authors' opinions on the possible aetiology. This literature review, coupled with clinical observations during a 5-year prospective study, prompts this proposal of the term mucosal enlargement underneath splinted and unsplinted mandibular implant overdentures.

Clinical effects of removable acrylic appliance design on gingival tissues: a short-term study

The aim of this study was to assess the effects on the gingiva when an experimental palatal acrylic removable appliance, was worn for 3 weeks. Clinical parameters were reassessed after a 3 week recovery period when the appliance was no longer worn. The appliance design featured a base plate on the right side which extended to the gingival margin, but which on the left, was relieved from the gingival margin by 6mm. Plaque index, gingival index, and probing depth were recorded on days 0, 7, and 21, and at day 42. Results indicated that there was increasing gingival inflammation in the right palatal gingiva by day 7, and this became worse by day 21. Statistically significant differences in gingival inflammation were evident when right and left sides were compared at day 7 and 21, although there were no significant differences in plaque accumulation during this period. Probing depth measurements also increased significantly on the right side by day 21. All these gingival changes reversed to baseline levels during the recovery period by day 42. This paper demonstrates the rapid effect of acrylic denture design on gingival tissues.