Goran I. Benic

A systematic review assessing soft tissue augmentation techniques

AIM The aim of the present review was to systematically assess the dental literature in terms of soft tissue grafting techniques. The focused question was: is one method superior over others for augmentation and stability of the augmented soft tissue in terms of increasing the width of keratinized tissue (part 1) and gain in soft tissue volume (part 2). METHODS A Medline search was performed for human studies focusing on augmentation of keratinized tissue and/or soft tissue volume, and complemented by additional hand searching. Relevant studies were identified and statistical results were reported for meta-analyses including the test minus control weighted mean differences with 95% confidence intervals, the I-squared statistic for tests of heterogeneity, and the number of significant studies. RESULTS Twenty-five (part 1) and three (part 2) studies met the inclusion criteria; 14 studies (part 1) were eligible for comparison using meta-analyses. An apically positioned flap/vestibuloplasty (APF/V) procedure resulted in a statistically significantly greater gain in keratinized tissue than untreated controls. APF/V plus autogenous tissue revealed statistically significantly more attached gingiva compared with untreated controls and a borderline statistical significance compared with APF/V plus allogenic tissue. Statistically significantly more shrinkage was observed for the APF/V plus allogenic graft compared with the APF/V plus autogenous tissue. Patient-centered outcomes did not reveal any of the treatment methods to be superior regarding postoperative complications. The three studies reporting on soft tissue volume augmentation could not be compared due to lack of homogeneity. The use of subepithelial connective tissue grafts (SCTGs) resulted in statistically significantly more soft tissue volume gain compared with free gingival grafts (FGGs). CONCLUSIONS APF/V is a successful treatment concept to increase the width of keratinized tissue or attached gingiva around teeth. The addition of autogenous tissue statistically significantly increases the width of attached gingiva. For soft tissue volume augmentation, only limited data are available favoring SCTGs over FGG.

E.A.O. guidelines for the use of diagnostic imaging in implant dentistry 2011. A consensus workshop organized by the European Association for Osseointegration at the Medical University of Warsaw

Diagnostics imaging is an essential component of patient selection and treatment planning in oral rehabilitation by means of osseointegrated implants. In 2002, the EAO produced and published guidelines on the use of diagnostic imaging in implant dentistry. Since that time, there have been significant developments in both the application of cone beam computed tomography as well as in the range of surgical and prosthetic applications that can potentially benefit from its use. However, medical exposure to ionizing radiation must always be justified and result in a net benefit to the patient. The as low a dose as is reasonably achievable principle must also be applied taking into account any alternative techniques that might achieve the same objectives. This paper reports on current EAO recommendations arising from a consensus meeting held at the Medical University of Warsaw (2011) to update these guidelines. Radiological considerations are detailed, including justification and optimization, with a special emphasis on the obligations that arise for those who prescribe or undertake such investigations. The paper pays special attention to clinical indications and radiographic diagnostic considerations as well as to future developments and trends.

Horizontal bone augmentation by means of guided bone regeneration

The development of bone augmentation procedures has allowed placement of dental implants into jaw bone areas lacking an amount of bone sufficient for standard implant placement. Thus, the indications for implants have broadened to include jaw regions with bone defects and those with a bone anatomy that is unfavorable for implant anchorage. Of the different techniques, the best documented and the most widely used method to augment bone in localized alveolar defects is guided bone regeneration. A large body of evidence has demonstrated the successful use of guided bone regeneration to regenerate missing bone at implant sites with insufficient bone volume and the long-term success of implants placed simultaneously with, or after, guided bone regeneration. However, the influence of guided bone regeneration on implant survival and success rates, and the long-term stability of the augmented bone, remain unknown. Many of the materials and techniques currently available for bone regeneration of alveolar ridge defects were developed many years ago. Recently, various new materials and techniques have been introduced. Many of them have, however, not been sufficiently documented in clinical studies. The aim of this review was to present the scientific basis of guided bone regeneration and the accepted clinical procedures. A classification of bone defects has been presented, aiming at simplifying the decision-making process regarding the choice of strategy for bone augmentation. Finally, an outlook into actual research and the possible future options related to bone augmentation has been provided.

Dimensions of buccal bone and mucosa at immediately placed implants after 7 years: a clinical and cone beam computed tomography study

OBJECTIVE The objective of this study was to evaluate the dimensions of buccal bone and soft tissue at immediately placed implants over a 7-year period. MATERIAL AND METHODS Twenty-four patients, that participated in a clinical prospective study and received implants immediately placed into extraction socket, were enrolled for this study. Residual bone defects were grafted with xenogenic bone substitute and covered by means of collagen membrane. Baseline examination included measurements of full-mouth plaque and bleeding scores, width of keratinized mucosa, and dimensions of residual bone defects at the buccal aspect. Seven years after implant placement, full-mouth plaque score, full-mouth bleeding score, width of keratinized mucosa, and probing pocket depth were assessed and cone beam computed tomography images acquired. Dimensions of buccal bone and soft tissue were evaluated on the cross-sectional cone beam computed tomography reconstructions. Differences between two time-points were tested using the two-sided t-test. Correlation analysis was used to investigate the influence of baseline bone defect dimensions on the bone dimensions measured at the 7-year follow-up. RESULTS AND CONCLUSIONS Fourteen patients attended the follow-up examination. In five implants almost no buccal bone was detected, whereas in the remaining nine implants the buccal bone was found covering the rough implant surface. No correlation was found between initial bone defects and bone dimensions at the follow-up examination. The sites without radiographically detectable buccal bone at the 7-year control presented with 1 mm more apical mucosal level in comparison to implants with intact buccal bone.

Systematic review of parameters and methods for the professional assessment of aesthetics in dental implant research.

OBJECTIVE The purpose of the present systematic review was to evaluate the scientific literature regarding the professional assessment of aesthetics in implant dentistry. MATERIAL AND METHODS An electronic search of Medline database and Cochrane Central Register of Controlled Trials was performed, and complemented by a manual search. Clinical or validation studies (Part 1) and randomized-controlled trials (RCTs) (Part 2) reporting parameters and methods for the assessment of aesthetics were included. The information regarding the assessment of aesthetics was extracted. The methodological quality of RCTs was evaluated by means of the Cochrane Collaborations Tool for assessing risk of bias. RESULTS The search yielded 149 and 32 publications in Part 1 and Part 2, respectively. A great diversity with regard to parameters, methods and measurement units used for the assessment of aesthetics was found among the included studies. With respect to time points of assessment there were significant differences between the RCTs. Only two RCTs fulfilled all the criteria of the The Cochrane Collaborations Tool for assessing risk of bias. CONCLUSIONS Due to the differences of the study designs, parameters and methods used for the assessment of aesthetics, comparisons between studies should be interpreted with caution. Only a limited number of RCTs offer sound evidence on aesthetic outcomes in implant dentistry.

Consensus Statements and Clinical Recommendations for Implant Loading Protocols

No abstract available.

Clinical and radiographic comparison of implants in regenerated or native bone: 5‐year results

PURPOSE The aim of this study was to test whether or not implants associated with bone regeneration show the same survival and success rates as implants placed in native bone in patients requiring both forms of therapy. MATERIAL AND METHODS Thirty-four patients (median age of 60.3 years, range 18-77.7 years) had been treated 5 years before the follow-up examination. Machined screw-type implants were inserted following one of two surgical procedures: (1) simultaneously with a guided bone regeneration (GBR) procedure, which involved grafting with xenogenic bone substitute material, autogenous bone or a mixture of the two and defect covering with a bio-absorbable collagen membrane (test) and (2) standard implantation procedure without bone regeneration (control). For data recording, one test and one control implant from each patient were assessed. Examination included measurements of plaque control record (PCR), probing pocket depth (PPD), bleeding on probing (BOP), width of keratinized mucosa (KM), frequency of situations with supra-mucosal location of the crown margin, implant survival assessment and radiographic examination. Radiographs were digitized to assess the marginal bone level (MBL). Differences between groups were tested using the one-sample t-test. The estimation of survival rate was based on Kaplan-Meier analysis. RESULTS The follow-up period of the 34 GBR and 34 control implants ranged from 49 to 70 months (median time 57 months). Cumulative survival rates reached 100% for the GBR group and 94.1% for the control group without statistical significance. No statistically significant differences for clinical and radiographic parameters were found between the two groups regarding PCR, BOP, PPD, KM and MBL. CONCLUSION The present study showed that, clinically, implants placed with concomitant bone regeneration did not performed differently from implants placed into native bone with respect to implant survival, marginal bone height and peri-implant soft tissue parameters.

Loading Protocols for Single-Implant Crowns: A Systematic Review and Meta-Analysis

PURPOSE To test whether or not immediate loading of single-implant crowns renders different results from early and conventional loading with respect to implant survival, marginal bone loss, stability of peri-implant soft tissue, esthetics, and patient satisfaction. MATERIALS AND METHODS An electronic search of Medline and Embase databases including studies published prior to August 1, 2012, was performed and complemented by a manual search. Randomized controlled trials (RCTs) comparing different loading protocols of single-implant crowns with a follow-up after restoration of at least 1 year were included. A meta-analysis yielded odds ratios (OR) and standardized mean differences (SMD) together with the corresponding 95% confidence intervals (95% CI). RESULTS The search provided 10 RCTs comparing immediate and conventional loading and 1 RCT comparing immediate and early loading. When assessing the implant survival at 1 year of loading, the meta-analysis of 10 studies found no significant differences between immediate and conventional loading (OR = 0.75; 95% CI: 0.32 to 1.76). The total difference of marginal bone loss during the first year of function between immediate and conventional loading protocols in 7 RCTs did not reach statistical significance (SMD = -0.05 mm; 95% CI: -0.41 to 0.31 mm). There were no significant differences between immediate and conventional loading regarding implant survival and marginal bone loss at 2, 3, and 5 years of loading. Three RCTs comparing the change of papilla level between immediate and conventional loading identified no significant differences. One study investigated the recession of the buccal mucosa after implant placement and found significantly inferior soft tissue loss for immediate loading as compared to conventional loading. Two RCTs investigated the recession of the buccal mucosa after insertion of the definitive crown and found no differences between immediate and conventional loading. The esthetics and the patient satisfaction were assessed in one and two RCTs, respectively. There were no significant differences between immediate and conventional loading. CONCLUSIONS Immediately and conventionally loaded single-implant crowns are equally successful regarding implant survival and marginal bone loss. This conclusion is primarily derived from studies evaluating implants inserted with a torque ≥ 20 to 45 Ncm or an implant stability quotient (ISQ) ≥ 60 to 65 and with no need for simultaneous bone augmentation. Immediately and conventionally loaded implants do not appear to differently affect the papilla height during the first year of loading. Due to the heterogeneity of the time point of baseline measurements and contradictory findings in the studies, it is difficult to draw clear conclusions regarding the recession of the buccal mucosa. With respect to the assessment of esthetic outcomes and patient satisfaction, the data available remain inconclusive.

Implant and Prosthodontic Survival Rates with Implant Fixed Complete Dental Prostheses in the Edentulous Mandible after at Least 5 Years: A Systematic Review

BACKGROUND The treatment of mandibular edentulism with implant fixed complete dental prostheses (IFCDPs) is a routinely used treatment option. PURPOSE The study aims to report the implant and prosthodontic survival rates associated with IFCDPs for the edentulous mandible after an observation period of a minimum 5 years. MATERIALS AND METHODS An electronic MEDLINE/PubMED search was conducted to identify randomized controlled clinical trials and prospective studies with IFCDPs for the edentulous mandible. Clinical studies with at least 5-year follow-up were selected. Pooled data were statistically analyzed and cumulative implant- and prosthesis survival rates were calculated by meta-analysis, regression, and chi-square statistics. Implant-related and prosthesis-related factors were identified and their impact on survival rates was assessed. RESULTS Seventeen prospective studies, including 501 patients and 2,827 implants, were selected for meta-analysis. The majority of the implants (88.5% of all placed implants) had been placed in the interforaminal area. Cumulative implant survival rates for rough surface ranged from 98.42% (95% confidence interval [CI]: 97.98-98.86) (5 years) to 96.86% (95% CI: 96.00-97.73) (10 years); smooth surface implant survival rates ranged from 98.93% (95% CI: 98.38-99.49) (5 years) to 97.88% (95% CI: 96.78-98.98) (10 years). The prosthodontic survival rates for 1-piece IFCDPs ranged from 98.61% (95% CI: 97.80-99.43) (5 years) to 97.25% (95% CI: 95.66-98.86) (10 years). CONCLUSION Treatment with mandibular IFCDPs yields high implant and prosthodontic survival rates (more than 96% after 10 years). Rough surface implants exhibited cumulative survival rates similar to the smooth surface ones (p > .05) in the edentulous mandible. The number of supporting implants and the antero-posterior implant distribution had no influence (p > .05) on the implant survival rate. The prosthetic design and veneering material, the retention type, and the loading protocol (delayed, early, and immediate) had no influence (p > .05) on the prosthodontic survival rates.

Cone beam computed tomography evaluation of regenerated buccal bone 5 years after simultaneous implant placement and guided bone regeneration procedures--a randomized, controlled clinical trial.

PURPOSE The aim of this controlled clinical study was to compare a polyethylene glycol membrane (PEG) used for bone regeneration of peri-implant defects to a collagen membrane with respect to implant survival rate, dimensions of buccal peri-implant bone and mucosa. MATERIALS AND METHODS Thirty-seven patients who received single tooth implants with simultaneous guided bone regeneration (GBR) in the posterior maxilla or mandible were enrolled in the study. Intra-operative heights of bone defects were assessed prior to bone augmentation. The defects were augmented with xenogenic bone mineral and randomly covered either with a porcine collagen membrane (control) or with a PEG membrane (test). Five years after implant placement, clinical evaluation and cone beam computed tomography (CBCT) scans were performed. Remaining height of bone defect, horizontal bone thickness, level of mucosal margin, and mucosal thickness were assessed in CBCT images. The difference of height of bone defect at implant placement and at 5-year follow-up was calculated. The differences between the two groups were analyzed using two-sided t-test and Mann-Whitney U-test. RESULTS After 5 years, 32 patients could be included and exhibited an implant survival rate of 100% for both groups. The buccal vertical bone gain between implant placement and 5-year follow-up amounted at 4.3 ± 1.5 (SD) mm and 4.8 ± 2.6 (SD) mm for the control and the test group, respectively (P = 0.493). Neither the bone height nor the thickness reached statistical significant differences between the two groups. The distance between mucosal margin and implant shoulder resulted in 0.8 ± 0.7 (SD) mm in the control and 0.5 ± 0.8 (SD) mm in the test group (P = 0.198). The mucosal thickness reached 1.4 ± 0.5 (SD) mm in the control and 1.3 ± 0.3 (SD) mm in the test group (P = 0.715). There were no significant correlations between height of bone defect at baseline and at follow-up examination and between different 5-year parameters. CONCLUSION A polyethylene glycol membrane used for bone regeneration of peri-implant defects performed as successfully as a collagen membrane with respect to implant survival rate and dimensions of the buccal peri-implant bone and mucosa after 5 years.