Fernando Suarez

Are Short Dental Implants (<10 mm) Effective? A Meta-Analysis on Prospective Clinical Trials

BACKGROUND This study aims to compare the survival rate of short (<10 mm) and standard (≥10 mm) rough-surface dental implants under functional loading. METHODS An electronic literature search using PubMed and Medline databases was conducted. Prospective clinical human trials, published in English from January 1997 to July 2011, that examined dental implants of <10 mm with a 12-month follow-up were included in this meta-analysis. The following data were retrieved from the included articles: the number of implants, implant dimensions, implant locations, types of prostheses, follow-up periods, and implant survival rates. Kaplan-Meier survival estimates and the hazard rates were analyzed and compared between short and standard implants. RESULTS Thirteen studies were selected, examining 1,955 dental implants, of which 914 were short implants. Short dental implants had an estimated survival rate of 88.1% at 168 months, when standard dental implants had a similar estimated survival rate of 86.7% (P = 0.254). The peak failure rate of short dental implants was found to occur between 4 and 6 years of function. This occurred at an earlier time point compared with standard dental implants, where the peak failure rate occurred between 6 and 8 years of function. CONCLUSIONS This study shows that in the long term, implants of <10 mm are as predictable as longer implants. However, they fail at an earlier stage compared with standard implants.

Reconstructive Procedures for Treating Peri-implantitis A Systematic Review

This review aimed at evaluating the effectiveness of reconstructive procedures for treating peri-implantitis. Searches of electronic databases and cross-referencing were performed for human comparative clinical trials with ≥10 implants for ≥12 months of follow-up, reporting radiographic defect fill and at least one of the following parameters: probing depth reduction, clinical attachment level gain, bleeding on probing reduction, and mucosal recession. The searches retrieved 430 citations. Only 1 randomized controlled trial was identified, which compared reconstructive therapy and open flap debridement. Case series studies were also included to evaluate the overall performance of the reconstructive procedures. Twelve studies were finally included. Meta-analysis revealed that the weighted mean radiographic defect fill was 2.17 mm (95% confidence interval [CI]: 1.46-2.87 mm), probing depth reduction was 2.97 mm (95% CI: 2.38-3.56 mm), clinical attachment level gain was 1.65 mm (95% CI: 1.17-2.13 mm), and bleeding on probing reduction was 45.8% (95% CI: 38.5%-53.3%). Great variability in reparative outcomes was found, attributed to patient factors, defect morphology, and reconstructive agents used. Currently, there is a lack of evidence for supporting additional benefit of reconstructive procedures to the other treatment modalities for managing peri-implantitis.

Surgical Management of Peri-Implantitis: A Systematic Review and Meta-Analysis of Treatment Outcomes

BACKGROUND This systematic review was requested by the Task Force of the American Academy of Periodontology as a follow-up study of the 2013 report, with an aim to investigate the efficacy of different surgical approaches to treat peri-implantitis. METHODS A search of four electronic databases from January 1990 to May 2013 was performed. Studies included were human clinical trials published in English that applied surgeries for treating peri-implantitis. Parameters evaluated included probing depth (PD) reduction, clinical attachment level gain, bleeding on probing (BOP) reduction, radiographic bone fill (RBF), and mucosal recession. The weighted mean (WM) and the 95% confidence interval of the studied parameters were estimated with the random-effect model. RESULTS A total of 1,306 studies were initially identified, after reviewing titles, abstracts, and full texts, and 21 articles, 12 of which were case series, were finally included. Four treatment groups were identified: 1) access flap and debridement; 2) surgical resection; 3) application of bone grafting materials; and 4) guided bone regeneration. The mean initial PD ranged from 4.8 to 8.8 mm, with initial BOP ranging from 19.7% to 100%. Short-term follow-ups (3 to 63 months) revealed that the available surgical procedures yielded a WM PD reduction of 2.04 (group 2) to 3.16 mm (group 4), or 33.4% to 48.2% of the initial PD. The WM RBF was 2.1 mm for groups 3 and 4. CONCLUSIONS Within the limitation of this systematic review, the application of grafting materials and barrier membranes resulted in greater PD reduction and RBF, but there is a lack of high-quality comparative studies to support this statement. The results might be used to project treatment outcomes after surgical management of peri-implantitis.

Effect of the Timing of Restoration on Implant Marginal Bone Loss: A Systematic Review

BACKGROUND The advancement in implant dentistry has allowed shortened treatment time by restoring the implants earlier. Whether the timing of restoration has an impact on implant marginal bone level has not been systematically analyzed. The aim of this study is to compare marginal bone loss (MBL) between implants that were restored with the following protocols: 1) immediate restoration/loading (IR/L); 2) early loading (EL); and 3) conventional loading (CL). METHODS An electronic literature search from three databases (until November 2011) and a hand search in implant-related journals were conducted. Clinical human studies in English language that had reported a comparison of MBL between implants with IR/L, EL, or CL with ≥12-month follow-up were included. In addition, the minimal number of implants had to be 10 for each group. Implants with both immediate placement (IP) and delayed placement (DP) were included and analyzed separately. An assessment of the publication bias for the included randomized clinical trials (RCTs) was performed. RESULTS The initial search resulted in 1,640 articles, of which 27 articles in full text were further evaluated for eligibility. Finally, 11 studies (eight RCTs, two controlled clinical trials, and one retrospective study) were qualified and classified into four groups: 1) IR/L + DP versus CL + DP (n = 6 articles); 2) IR + DP versus EL + DP (n = 2 articles); 3) EL + DP versus CL + DP (n = 1 article); and (4) IL + IP versus CL + IP (n = 2 articles). A meta-analysis performed for group 1 showed 0.09 mm (95% confidence interval = -0.27 to 0.09 mm) difference in the mean MBL, favoring the IR/L protocol but without significant difference (P = 0.33). No significant difference in MBL was found for groups 2 through 4 after adjusting for the implant placement level. The eight RCTs were determined to be at moderate-to-high risk of publication bias. CONCLUSIONS This meta-analysis does not show an effect of the timing of restorations on implant MBL. The selection of restoration protocols should be based on factors other than MBL.

On the Feasibility of Utilizing Allogeneic Bone Blocks for Atrophic Maxillary Augmentation

Purpose. This systematic review was aimed at assessing the feasibility by means of survival rate, histologic analysis, and causes of failure of allogeneic block grafts for augmenting the atrophic maxilla. Material and Methods. A literature search was conducted by one reviewer in several databases. Articles were included in this systematic review if they were human clinical trials in which outcomes of allogeneic bone block grafts were studied by means of survival rate. In addition other factors were extracted in order to assess their influence upon graft failure. Results. Fifteen articles fulfilled the inclusion criteria and subsequently were analyzed in this systematic review. A total of 361 block grafts could be followed 4 to 9 months after the surgery, of which 9 (2.4%) failed within 1 month to 2 months after the surgery. Additionally, a weighed mean 4.79 mm (95% CI: 4.51–5.08) horizontal bone gain was computed from 119 grafted sites in 5 studies. Regarding implant cumulative survival rate, the weighed mean was 96.9% (95% CI: 92.8–98.7%), computed from 228 implants over a mean follow-up period of 23.9 months. Histologic analysis showed that allogeneic block grafts behave differently in the early stages of healing when compared to autogenous block grafts. Conclusion. Atrophied maxillary reconstruction with allogeneic bone block grafts represents a reliable option as shown by low block graft failure rate, minimal resorption, and high implant survival rate.

Prosthetic Abutment Height is a Key Factor in Peri-implant Marginal Bone Loss

In this study, we analyzed the influence of prosthetic abutment height on marginal bone loss (MBL) around implants in the posterior maxilla. In this retrospective cohort study, the radiographically determined MBL was related to the height of the abutments of internal conical connection implants at 6 and 18 months post-loading. Data were gathered on age, sex, bone substratum, smoking habit, history of periodontitis, and prosthetic features, among other variables. A linear mixed model was used for statistical analysis. The study included 131 patients receiving 315 implants. MBL rates at 6 and 18 months were mainly affected by the abutment height but were also significantly influenced by the bone substratum, periodontitis, and smoking habit. MBL rates were higher for prosthetic abutment < 2 mm vs. ≥ 2 mm, for periodontal vs. non-periodontal patients, for grafted vs. pristine bone, and for a heavier smoking habit. The abutment height is a key factor in MBL. MBL rates followed a non-linear trend, with a greater MBL rate during the first 6 months post-loading than during the next 12 months.

Implant surface detoxification: a comprehensive review.

Objective:Nonsurgical treatment has been shown to be effective in dealing with inflammatory lesions around implant without bone loss. However, when bone loss is noticed, surgical treatment may be needed. Nonetheless, before the surgical approaches can be effective, the contaminated implant surface has to be detoxified. Many detoxifying agents/techniques have been proposed and have shown varieties of outcomes, these include but not limited to: citric acid, chlorhexidine, local and systemic antibiotics, hydrogen peroxide, air-powder abrasive, laser and photodynamic therapy, and implantoplasty using burs. Hence, the aim of this review was to evaluate them in terms of their ability in achieving implant surface detoxification. Materials and Methods:A search of PubMed and a hand search of articles were conducted up to December 2011. Different keywords related to the treatment of peri-implant diseases were used. Results:At this time, all techniques/agents have shown to be equally effective to detoxify the contaminated implant surface. Conclusion:Comparative studies of different detoxification methods are heterogeneous, leaving a few voids when selecting a specific technique for detoxifying the contaminated implant surface.

Implants for orthodontic anchorage: success rates and reasons of failures.

Introduction:The aims of this study were to analyze the success rate of mini-implants and miniscrews and to report the reasons behind them. Materials and Methods:An electronic literature search from PubMed databases and a hand search in implant- and orthodontic-related journals were performed until December 31, 2011. Human clinical studies in English that reported temporary anchorage devices used for orthodontic purpose with at least 6 months follow-up were included. In addition, the minimal number of implants had to be at least 10. Implants placed in maxilla, mandible, and hard palate were included. Results:The initial search resulted in 847 articles, of which 46 were further evaluated. Finally, 29 studies were qualified and classified into 2 groups: implants placed in maxilla and mandible (group 1) and implants placed in hard palate (group 2). A meta-analysis performed for groups 1 and 2 showed 87.8% and 93.8% survival rate, respectively. In addition, the most common cause for implants failure was surgery-related factors. Conclusion:Mini-implant survival rate is location dependent, with those placed in the palate showing higher success rates. In addition, failures most commonly occur because of surgery-related factors.

Evaluation of maxillary sinus width on cone-beam computed tomography for sinus augmentation and new sinus classification based on sinus width

PURPOSE The degree of difficulty in performing lateral window sinus augmentation may depend on the morphology of the maxillary sinus. The aim of this was to measure the distances between the medial and lateral sinus wall (sinus width [SW]) at different levels and apply those SW values to formulate a new sinus classification. MATERIALS AND METHODS Edentulous sites adjacent to maxillary sinuses with inadequate ridge height (RH; <10 mm) were included from cone-beam computed tomography database in the University of Michigan. SW was measured at the heights of 5, 7, 10, 13, and 15 mm from alveolar crest at the edentulous sites. Mean SW was stratified by residual RH into three different groups (group 1: <4 mm, group 2: ≥4 and <7, and group 3: ≥7 and <10), study sites (first and second premolars and molars), and measurement levels. RESULTS Three hundred and twenty subjects (mean 50.1 years old) with 422 edentulous sites were included. Mean SW was wider at molar sites, higher measurement levels, and sites with shorter residual RH. Mean SW at the lower (average 2.3 mm from sinus floor) and higher boundary (15 mm from the alveolar crest) of lateral window osteotomy was 9.0 (2.8) and 16.0 (4.4) mm, respectively. Narrow, average, or wide sinuses were classified when the SW was <8, 8-10 and >10 mm at the lower boundary or <14, 14-17 and >17 mm at the upper boundary, respectively. CONCLUSION SW at levels that were relevant to lateral window sinus augmentation was measured. The proposed sinus classification could facilitate communication between health providers and determine the degree of easiness of sinus augmentation. It might be particularly useful for the selection of grafting materials and surgical approaches. Further studies are required to test its clinical implications.

Guidelines for the diagnosis and treatment of peri-implant diseases.

Although some risk factors of peri-implant disease are well defined, the lack of efficient and predictable approaches to treat peri-implantitis has created difficulty in the management of those complications. The aim of this review was to evaluate the reliability of the diagnosis methods and to provide a set of guidelines to treat peri-implant diseases. A search of PubMed and a hand search of articles related to peri-implant diseases were conducted up to August 2013. A summary of the current methods for the diagnosis of peri-implantitis, its potential risk factors, and a flow chart to guide the clinical management of these conditions are presented.