A 10-year prospective clinical and radiographic study of one-stage dental implants

Dental Implants: Enhancing Biological Response Through Surface Modifications

Surface characteristics are an important factor for long-term clinical success of dental implants. Alterations of implant surface characteristics accelerate or improve osseointegration by interacting with the physiology of bone healing. Dental implant surfaces have been traditionally modified at the microlevel. Recently, researchers have actively investigated nano-modifications in dental implants. This review explores implant surface modifications that enhance biological response at the interface between a bone and the implant.

Prophylactic antibiotics for staged bone augmentation in implant dentistry

Background: The objective of the study was to assess the effect of prophylactic antibiotics on the outcome of bone augmentation and subsequent dental implant placement by combining the recommended quality assessment methods for systematic reviews and primary studies.Materials and methods: This is a complex systematic review in which systematic reviews as well as primary studies are scrutinised. A search of Medline (OVID), The Cochrane Library (Wiley) and EMBASE, PubMed and Health technology assessment (HTA) organisations as-well as a complementary hand-search was carried out. Selected primary studies were assessed using GRADE. Each study was reviewed by three authors independently.Results: Abstract screening yielded six potential systematic reviews allocated for full-text inspection. A total of ten primary studies were read in full-text. No relevant systematic reviews regarding the topic of this article were found. The quality assessment resulted in two primary studies with a moderate risk of bias. Of the two studies with a moderate risk of bias, one compared a single dose of clindamycin 600 mg preoperatively with the same preoperative dose followed by four doses of 300 mg every 6 h. The second study compared a single dose prophylaxis of two different types of antibiotic compounds.Conclusion: In conclusion, the scientific evidence regarding the use of antibiotic prophylaxis for reducing the risk of infection in conjunction with bone augmentation procedures during dental implant placement is very limited. The infection rate as compared to nonusage of prophylactic antibiotics, selection of the most suitable compound, and the optimal duration of prophylactic treatment is still unknown.

A method to evaluate the accuracy of dental implant placement without postoperative radiography after computer-guided implant surgery: A dental technique

This technique allows evaluation of the accuracy of a dental implant's position after computer-guided surgery without postoperative radiography. Once the scanned implant and scan body file were prepared, the position of the placed implant was verified by using a computer-guided implant software program instead of radiography, thus reducing radiation exposure.

Complex systematic review - Perioperative antibiotics in conjunction with dental implant placement

OBJECTIVES

The aim of this study was to revisit the available scientific literature regarding perioperative antibiotics in conjunction with implant placement by combining the recommended methods for systematic reviews and complex systematic reviews.

MATERIAL AND METHODS

A search of Medline (OVID), The Cochrane Library (Wiley), EMBASE, PubMed and Health technology assessment (HTA) organizations was performed, in addition to a complementary hand-search. Selected systematic reviews and primary studies were assessed using GRADE and AMSTAR, respectively. A meta-analysis was performed.

RESULTS

The literature search identified 846 papers of which 10 primary studies and seven systematic reviews were included. Quality assessment of the systematic reviews revealed two studies of moderate risk of bias and five with high risk of bias. The two systematic reviews of moderate risk of bias stated divergent numbers needed to treat (NNT) to prevent one patient from implant failure. Four of the primary studies comparing antibiotic prophylaxis with placebo were estimated to be of low, or moderate, risk of bias and subjected to meta-analysis. The NNT was 50 (pooled RR 0.39, 95% CI 0.18, 0.84; P = 0.02). None of these four studies individually show a statistical significant benefit of antibiotic prophylaxis. Furthermore, narrative analysis of the studies eligible for meta-analysis reveals clinical heterogeneity regarding intervention and smoking.

CONCLUSION

Antibiotic prophylaxis in conjunction with implant placement reduced the risk for implant loss by 2%. However, the sub-analysis of the primary studies suggests that there is no benefit of antibiotic prophylaxis in uncomplicated implant surgery in healthy patient.

Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review

The aim of this systematic review was to evaluate the survival and success rates of osseointegrated implants determined in longitudinal studies that conducted a follow-up of at least 10 years. A broad electronic search was conducted in MEDLINE/PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) for relevant publications in indexed journals, evaluating the clinical performance of dental implants. Using inclusion and exclusion criteria, two reviewers analyzed titles, abstracts, and complete articles, prioritizing studies of the randomized clinical trial type. A total of 23 articles were included in this review. Ten prospective studies, nine retrospective studies, and four randomized clinical trials, which evaluated 7711 implants, were selected. The mean follow-up time of the studies included was 13.4 years. All of the studies reported survival rates and mean marginal bone resorption values, with cumulative mean values of 94.6% and 1.3mm, respectively. Fourteen studies related success rates. Taking into consideration the disparate outcome measures employed to assess dental implant performance and within the limitations of this systematic review, we may affirm that osseointegrated implants are safe and present high survival rates and minimal marginal bone resorption in the long term.

Factors Associated With Crestal Bone Loss Following Dental Implant Placement in a Longitudinal Follow-up Study

The purpose of this study is to estimate the magnitude of crestal bone loss and to identify factors associated with changes in crestal bone height following placement of dental implants. This was a retrospective cohort study, consisting of a sample derived from the population of patients who had at least 1 dental implant placed in a community practice over a 10-year period. A total of 11 predictor variables were grouped into demographic, related health status, anatomic, implant-specific, and operative categories. The primary outcome variable was a change in crestal bone height (mm) over the course of follow-up. The secondary outcome variable was crestal bone loss at 1 year grouped into 2 categories (bone loss >1.5 mm and ≤1.5 mm). Univariate and multivariate regression mixed-effects models were developed to identify variables associated with crestal bone level changes over time. P values ≤.05 were considered statistically significant. The study sample was composed of 85 subjects who received 148 implants. The mean change of the crestal bone was -2.1 ± 1.5 mm (range = -12.5 to 0.5 mm; median = -1.77 mm). In the multivariate model, none of the variables studied were statistically associated with mean crestal bone loss. Among 84 (66.1%) implants with bone loss >1.5 mm within 1 year, no variables were associated with bone loss in the multivariate model. Of the 11 predictor variables evaluated in this study, none were statistically significant with regard to an increased risk for crestal bone loss or for excessive bone loss within the first year after implant placement.

Clinical and radiographic outcome of dental implants supporting fixed prostheses: the relevance of cortical bone formation

PURPOSE

To evaluate the hard and the soft tissue parameters around implants supporting fixed prostheses over a period of 5 years and the possible association to the increase in periimplant bone density (IPBD).

MATERIAL AND METHODS

A total of 39 dental implants placed in 29 patients were included in the study. Periimplant clinical (gingival index, probing depth, keratinized mucosa, sulcus fluid flow rate) and radiographic variables (bone loss, bone density) were collected, and the data analysis performed.

RESULTS

Periimplant hard and soft tissue parameters remained stable throughout the follow-up period. Of the 39 implants, 20 demonstrated IPBD. The mean distance between first bone-to-implant contact and the microgap for implants with and without IPBD was significantly different at 1-year, 2-year, and 5-year follow-up. The evidence of IPBD demonstrated no influence on the periimplant soft tissue parameters. All mean values of bone density for implants with IPBD were higher than those for implants without IPBD throughout the whole observation period.

CONCLUSION

All implants were clinically successful over the period of follow-up. IPBD might be more indicative of a stable periimplant bone level.

Does implant staging choice affect crestal bone loss?

PURPOSE

The purpose of the present study was to compare the crestal bone loss around implants placed according to either a 1-stage or 2-stage implant installation procedure using a digital subtraction radiography technique.

MATERIALS AND METHODS

In the present randomized clinical trial, screw-shaped tapered implants were inserted in the posterior mandible of patients needing fixed partial dentures. In each edentulous area, according to the randomization table, 1 implant was inserted using a 1-stage procedure (group 1) and 1 was placed using a 2-stage approach (group 2). The implants were temporized with the relined denture after 2 weeks. All implants were functionally loaded with fixed partial dentures after 3 months. Crestal bone loss (primary outcome variable) was measured using a digital subtraction radiography technique. Standardized radiovisiographs were taken after implant insertion, after fixed partial denture installation (3 months after surgery), and after 6 and 12 months of functional loading. The data were analyzed using the Wilcoxon signed ranks test (α = 0.05).

RESULTS

Eleven patients (mean age 46.9 years, 3 women and 8 men) were included in the study. A total of 34 implants were inserted, 17 using a 1-stage protocol and 17 using a 2-stage protocol. Three months after implant placement, the 2-stage implants showed significantly more crestal bone loss (0.65 ± 0.71 mm) than the 1-stage implants (0.41 ± 0.53 mm; P = .02). However, after 6 and 12 months of functional loading, both groups showed comparable changes in bone level (P > .05).

CONCLUSIONS

No differences were found between 1-stage and 2-stage implant placement in crestal bone loss after 1 year of functional loading.

Clinical and microbiological characteristics of peri-implantitis cases: a retrospective multicentre study

OBJECTIVES

The aim of this study was to follow patient cases retrospectively in a longitudinal manner from the time of implant placement to the time they were diagnosed with peri-implant disease, and to identify associated clinical and microbiological features of peri-implant disease.

MATERIAL AND METHODS

A total of 281 patient cases were chosen from the archives of the Oral Microbiological Diagnostic Laboratory, Gothenburg, Sweden, based on bacterial samples taken from diseased implants. A form was designed and filled in separately for each case including data on patient, implant and disease profile.

RESULTS

Most cases were severe peri-implantitis cases (91.4%). In 41.3% of the patients, peri-implantitis was developed early, already after having implants in function less than 4 years. The type of implant surface was significantly associated with the time in years implants were in function, before disease was developed (P < 0.05). The microbiological results by both culture and checkerboard analysis, although failed to fully correspond to the severity of the disease in terms of magnitude, proved to show that peri-implantitis is a polymicrobial anaerobic infection with increased number of AGNB (aerobic Gram-negative bacilli) in 18.6% of the patients.

CONCLUSIONS

Peri-implantitis is a biological complication of implants in function that poses a threat to their long-term survival. It may develop earlier around implants with rough surfaces and it may represent a true infection. Microbiological sampling methods should be improved and uniformed so as to fully unveil the microbiological profile of the disease.

Long-term rabbits bone response to titanium implants in the presence of inorganic bovine-derived graft

This study evaluated bone responses to titanium implants in the presence of an inorganic graft material. The bilateral mandible incisors of 24 rabbits were surgically extracted and one of the exposed sockets, chosen at random, was filled with an inorganic xenogenic bone graft (Gen-ox®), whereas the remaining socket was left to heal naturally and served as a control. After 60 days, titanium implants were inserted in the specific areas, and on days 0, 30, 60, and 180 after the implant insertions, six animals of each group were killed. Digital periapical radiography of implant region was obtained and vertical bone height (VBH) and bone density (BD) were evaluated by digital analysis system. In the undecalcified tissue cuts, bone-to-implant contact (BIC) and bone area (BA) within the limits of the implant threads were evaluated and compared statistically by means of two-way ANOVA and Tukey's test (ρ < 0.05). No significant differences were detected in VBH and BA, either between groups or between different experimental intervals. The BD was significantly higher in the experimental group than in the control group in all the intervals tested, but there were no significant differences by interval. The BIC was statistically lower in the control group on day 0; however, a significant increase was observed on days 60 and 180 (ρ < 0.05). The use of an inorganic xenograft prior to insertion of a titanium implant did not interfere with the course of osseointegration.