Keratinized mucosa width assessment at implant sites using high-frequency ultrasonography.

BACKGROUND: The aim of this study was to describe the application of high-frequency ultrasonography (HFUS) for assessing keratinized mucosa (KM) width at implant sites. METHODS: KM width was measured at 28 implant sites exhibiting a peri-implant soft tissue dehiscence at baseline and 12 months after soft tissue augmentation. KM width assessment was performed with a periodontal probe [clinical assessment (clKM)] and with HFUS, based on the echointensity of the keratinized epithelium compared to the adjacent structures. KM width measurements on ultrasound scans were performed linearly (lnKM) and along the soft tissue profile [surface distance (sdKM)]. RESULTS: No statistically significant differences were observed between clKM, lnKM, and sdKM at baseline, while at 12 months, sdKM (5.313 ± 1.188 mm) was significantly higher than clKM (3.98 ± 1.25 mm) and lnKM (4.068 ± 1.197 mm) (P < 0.001 for both comparisons). A linear relationship between mucosal thickness (MT) and the difference between sdKM and lnKM was observed. In 95.2% of cases with MT > 2.51 mm, the discrepancy between sdKM and lnKM was at least 1 mm. CONCLUSIONS: HFUS is a noninvasive and valuable tool for measure KM width at implant site. Evaluating KM width along the soft tissue profile as a surface distance may improve the accuracy of the assessment.

The peri-implant mucosa color: A systematic appraisal of methods for its assessment and clinical significance.

BACKGROUND: Peri-implant mucosa color (PMC) seems to be one of the main parameters affecting the esthetic outcome of implant therapy. However, more emphasis should be given to its assessment and reporting. PURPOSE: To describe the available evidence on methods to assess and report the color of the peri-implant mucosa (PMC) and the respective clinical relevance. MATERIAL AND METHODS: A comprehensive electronic and manual search was performed to identify clinical studies reporting on PMC. RESULTS: A total of 121 studies were included. PMC was evaluated at the time of the follow-up visit (chairside) in 45.5% studies. PMC assessment was performed qualitatively, by comparing PMC with adjacent and/or contralateral gingiva (78.6%) or quantitatively, using spectrophotometry (20.7%) or a software on clinical photographs (0.8%). The most performed method to assess PMC was through esthetic indices (76.9%), either at the time of the follow-up visit (chairside) or at later time point using photographs. Quantitative reporting of PMC included averages of points from esthetic indices or color differences to natural gingiva expressed with the CIELAB color system. PMC assessment allowed describing color discrepancies compared to natural gingiva, evaluating color changes over time, and comparing the outcomes of different treatment modalities. PMC assessment through spectrophotometry was additionally utilized to assess the role of mucosal thickness (MT) on PMC. CONCLUSIONS: Various methods for PMC assessment and reporting were described, including visual assessment, mainly through esthetic indices, and spectrophotometry. PMC evaluation has allowed to demonstrate the factors affecting the color of the peri-implant soft tissue, such as the type of abutment/restoration, MT, and soft tissue augmentation.

Alveolar ridge preservation: Complications and cost-effectiveness.

Alveolar ridge preservation is routinely indicated in clinical practice with the purpose of attenuating postextraction ridge atrophy. Over the past two decades numerous clinical studies and reviews on this topic have populated the literature. In recent years the focus has primarily been on analyzing efficacy outcomes pertaining to postextraction dimensional changes, whereas other relevant facets of alveolar ridge preservation therapy have remained unexplored. With this premise, we carried out a comprehensive evidence-based assessment of the complications associated with different modalities of alveolar ridge preservation and modeled the cost-effectiveness of different therapeutic modalities as a function of changes in ridge width and height. We conclude that, among allogeneic and xenogeneic bone graft materials, increased expenditure does not translate into increased effectiveness of alveolar ridge preservation therapy. On the other hand, a significant association between expenditure on a barrier membrane and reduced horizontal and vertical ridge resorption was observed, though only to a certain degree, beyond which the return on investment was significantly diminished.

Reliability assessment of the classification for facial peri-implant soft tissue dehiscence/deficiencies (PSTDs): A multi-center inter-rater agreement study of different skill-level practitioners.

BACKGROUND: Along with the popularity of dental implants, implant esthetic complications are also on the rise. Recently a classification was proposed to comprehensively evaluate these conditions, with the definition of peri-implant soft tissue dehiscence/deficiencies (PSTDs). The aim of this article was therefore to test the inter-examiner agreement when utilizing the established rubrics among 25 standardized cases and 34 clinicians of different skill levels. METHODS: Twelve periodontal residents, 12 general dentists, and 10 periodontists participated in this study. All examiners were provided with photographs of 25 single PSTDs and asked to rate all cases based on the proposed classification at a single timepoint. Variance components analysis was conducted with multilevel regression fit in a Bayesian framework to obtain uncertainty intervals for fractional variance contributions and interclass correlation values (ICC) to assess the agreement in the rating of all cases, among all examiners, different skill-level practitioners, and to compare their responses relative to the judgment of a gold standard examiner. RESULTS: Overall, the results showed reproducible and consistent responses among the 34 examiners, and in each subgroup of skill-level, comparable to that of the gold examiner. Nevertheless, periodontists and residents were more likely to agree with the response of the gold standard examiner in their assessments of class and subclass of the PSTDs. CONCLUSIONS: The proposed PSTD classification showed reproducible assessments among all examiners, and between examiners of the same skill-level. The response of the gold standard examiner was more in line with the assessment of the periodontists and periodontal residents.

Gingival Phenotype Modification as a Result of Root Coverage Procedure with Two Human Dermal Matrices: Long-Term Assessment of a Randomized Clinical Trial.

The gingival thickness (GT) and keratinized tissue width (KTW) constitute the gingival phenotype, a concept that has received a great deal of appreciation in recent years. Gingival phenotype modification has been achieved via different surgical techniques and grafting materials. Despite the superiority of autogenous grafts, their increased patient morbidity and limited recourse has led to the development of graft substitutes. The human dermal matrix is a notable example that, depending on its processing method, can become freeze-dried or solvent-dehydrated acellular dermal matrix (FDADM and SDADM, respectively). This article reports the 9-year outcomes of a randomized clinical trial regarding gingival phenotype modification following root coverage with FDADM and SDADM. Twelve of the original 20 patients were available at the 9-year follow-up. Overall, the outcomes of gingival phenotype modification were maintained in both groups and at all sites after 9 years. For KTW, an incremental increase was observed over time in both groups, and minimal or no changes were noted in GT from the 1-year recall to the 9-year recall. However, the gingival margin level showed an apical shift for both groups.

Acellular dermal matrix for root coverage procedures: 9-year assessment of treated isolated gingival recessions and their adjacent untreated sites.

BACKGROUND: The long-term outcomes of acellular dermal matrix (ADM) for the treatment of isolated gingival recessions has not yet been evaluated. Thus, the aim of this study was to observe the root coverage outcomes of coronally advanced flap with ADM over time, and compare them with their adjacent untreated sites. METHODS: Twelve patients (from 20) were available at the 9-year recall. Clinical parameters (recession depth, mean root coverage [mRC], keratinized tissue width [KTW], and gingival thickness) were evaluated and compared with the 1-year results, and the ADM-adjacent untreated sites (on mesial and distal) via mixed-modeling regression analyses. RESULTS: From 1 to 9 years, the ADM-treated isolated recessions showed a relapse from 77% to 62% mRC (P <0.05). A similar pattern toward apical shift of the gingival margin was noticed for the ADM-adjacent untreated sites without baseline recession. However, ADM-adjacent untreated sites which had presented with recession at baseline but were not treated showed a significantly more apical shift of the gingival margin (almost two-fold). A significant increase in KTW was noted for all sites. Baseline KTW ≥2 mm was a significant predictor for the stability of the gingival margin at the ADM-treated, and the ADM-adjacent sites with baseline recession. CONCLUSIONS: ADM-treated sites displayed recession relapse from 1 to 9 years. The untreated adjacent sites with a recession at baseline, showed a higher apical displacement of the gingival margin compared with the ADM-treated sites, and ADM-adjacent sites without a recession at baseline.

Long-term Clinical Outcomes and Cost-Effectiveness of Full-Arch Implant-Supported Zirconia-Based and Metal-Acrylic Fixed Dental Prostheses: A Retrospective Analysis.

PURPOSE: To provide a long-term comparison of metal-acrylic and zirconia implant-supported fixed complete dental prostheses. MATERIALS AND METHODS: Patients treated with a metal-acrylic or zirconia fixed implant prosthesis with a minimum 5-year follow-up were included. All complications were registered, along with events such as peri-implantitis and implant failure. Survival and all costs associated with the prostheses were assessed to provide an overall evaluation of each type of fixed implant prosthesis protocol. RESULTS: Seventy-four rehabilitated arches (43 metal-acrylic, 31 zirconia, mean follow-up: 8.7 ± 3.37 years) were included. Delayed complications accompanied the metal-acrylic prostheses more frequently. In both groups, single tooth chipping/fracture was the most prominent minor complication, and incidence of multiple teeth and framework fracture was the most frequent major complication. Zirconia fixed implant prostheses demonstrated higher prosthetic survival rates than the metal-acrylic prostheses (93.7% ± 5.5% at 5 years vs 83.0% ± 11.1%). No difference was observed for peri-implantitis or implant failure. The initial cost for zirconia prosthesis fabrication was significantly higher than metal-acrylic hybrids (an estimated difference of $7,829 [P < .001]); however, due to reduced complication rates for the zirconia fixed implant prosthesis, maintenance and treatment for complications did not greatly differ between groups. CONCLUSION: Within the limitations, zirconia fixed implant prostheses presented higher initial costs than metal-acrylic hybrids, however, with satisfactory outcomes, reduction of overall complications, and superior survival rates.

Guided tissue regeneration combined with bone allograft in infrabony defects: Clinical outcomes and assessment of prognostic factors.

BACKGROUND: Clinical data on the outcomes of guided tissue regeneration (GTR) is scarce. The aim of this retrospective cohort study was to evaluate the outcomes after GTR, their stability and the survival of the treated teeth with periodontal infrabony defects. METHODS: Infrabony defects treated with GTR using a bioabsorbable membrane and a bone graft substitute with at least 1-year follow-up were included. Survival and regression analyses were conducted to evaluate the outcomes, their stability, and the retention of the teeth. The effect of recorded variables on clinical attachment gain (CAL) and tooth survival were assessed via Cox proportional-hazards models and multivariate generalized linear models. RESULTS: One hundred seventy-five treated defects were selected from a total of 641 charts. The average follow-up was 5.75 ± 4.6 years. At baseline, the mean CAL was 9.56 ± 1.93 mm with a mean pocket depth (PD) of 8.41 ± 1.42 mm. At the 1-year post-surgical recall, 3.55 ± 1.85 mm of CAL gain and 3.87 ± 1.87 mm PD reduction were observed (P < 0.05). The 5- and 10-year survival rates of the treated teeth were 85.0% and 72.7%, respectively. Baseline PD, smoking, and membrane exposure were significantly related to CAL gain, whereas baseline CAL, age, frequency in maintenance visits significantly affected tooth survival. CONCLUSION: Within the limitations of this study, data suggests GTR is a good option for the treatment of infrabony defects because it can improve both tooth retention rate and overall clinical outcomes.

Long term assessment of root coverage stability using connective tissue graft with or without an epithelial collar for gingival recession treatment. A 12-year follow-up from a randomized clinical trial.

AIM: To evaluate the long term root coverage outcomes of coronally advanced flap plus a connective tissue graft with (CAF + CTG) or without an epithelial collar (CAF + ECTG), and evaluate the adjacent treated sites included in the flap. METHODS: Seventeen of the original 20 subjects included in the randomized clinical trial were available at 12 years (43 sites). Mean root coverage (mRC), keratinized tissue width (KTW), gingival thickness (GT) on the grafted and adjacent sites were evaluated and compared with baseline and 6 months. RESULT: There was a reduction in the mRC at all sites: 16.52% in the CAF + CTG (p > .05), 19.42% in the CAF + ECTG (p < .05) and 34.12% in the CAF-alone (adjacent treated sites) group (p < .05). No significant differences were observed within the groups for changes in KTW, GT and clinical attachment level (CAL) (p > .05). Keratinized tissue width at baseline and at 6 months was found to be predictors for the stability of the gingival margin in the long term. CONCLUSIONS: CAF + CTG and CAF + ECTG were found equally efficacious in maintaining the levels of the gingival margin with a small amount of relapse over the period of 12 years while CAF-alone sites showed a greater gingival recession (GR) reoccurrence.

Microscope and micro-camera assessment of Schneiderian membrane perforation via transcrestal sinus floor elevation: A randomized ex vivo study.

OBJECTIVE: We sought to assess the effectiveness of using a microscope and non-invasive camera for assessing sinus membrane perforations during transcrestal sinus floor elevation (TSFE). MATERIALS AND METHODS: Five fresh human cadaver heads corresponding to eight maxillary sinuses (six bilateral and two unilateral) underwent 4 TSFEs per sinus (a total of 32 single site elevations). Each elevation was randomly assigned to receive a three or six mm membrane elevation height (MEH). A microscope and micro-camera were used to assess the sinus membrane perforation. Afterwards, radiological and clinical membrane perforation assessments were performed. The statistical analysis results are expressed using the means, standard deviations, range values of the residual ridge height (RRH), residual ridge width (RRW), sinus membrane thickness (SMT) and incidence of perforation (IoP). Generalized linear methods were used to test for the correlation of RRH and MEH to the microscope and micro-camera perforation assessments and the correlation of microscope and micro-camera assessments with the post-operative CBCT and crestal liquid evaluation. RESULTS: The cumulative percentage of IoP was 40.62%, (23.07% with 3 mm MEH, and 76.92% with 6 mm MEH, p < 0.05). The perforation assessed using either the microscope or micro-camera coincided with the post-operative CBCT and crestal liquid assessment in 87.55% sites. No significant correlation was found between the microscope or micro-camera assessments with RRH or MEH. CONCLUSION: Application of a microscope and micro-camera during transcrestal sinus floor elevation may allow the detection of the integrity of the Schneiderian membrane with greater than 85% accuracy in this ex vivo model.

Comparison of three different types of implant-supported fixed dental prostheses: A long-term retrospective study of clinical outcomes and cost-effectiveness.

OBJECTIVE: To study the performance of 2-3 posterior bone-level dental implants constructed with either three non-splinted crowns (NSC), three splinted crowns (SC), or a 3-unit implant-supported bridge over two implants (ISB). MATERIAL AND METHODS: Patients treated with three metal-ceramic NSC, SC, or an ISB were included in the present retrospective study. Implant survival and success rate as well as all biological and technical complications were collected. The cost associated with each of the treatment options was evaluated in the comparative analysis. RESULTS: One hundred and forty-five patients (40 NSC, 52 SC, and 53 in the ISB) receiving 382 bone-level implants (120 NSC, 106 ISB, and 156 SC) were included (mean follow-up of 76.2 months). Lack of success was observed in 33.8% of the total patient sample, being lower in the ISB group. Implant survival rates were 92.5% in the NSC, 100% in the ISB, and 88.5% in the SC, with significant difference noted between the ISB and SC (p = 0.01). Overall, 9.9% of the total implants were found to have peri-implantitis (PI), with 16.7% in the SC, 7.5% in the NSC, and 2.8% in the ISB. Patients presenting prosthodontic complications were significantly higher in NSC (32.5%) than ISB (13.2%) and SC (15.4%). The total cost of the ISB group was significantly lower when compared to the NSC and SC groups (p < 0.001). CONCLUSIONS: An 3-unit implant-supported bridge restoring 2 implants seems to present the most ideal long-term therapeutic solution, among the investigated approaches in this study, in rehabilitating a 3-unit edentulous area.

Clinical outcomes and cost effectiveness of computer-guided versus conventional implant-retained hybrid prostheses: A long-term retrospective analysis of treatment protocols.

BACKGROUND: Computer-guided systems were developed to facilitate implant placement at optimal positions in relation to the future prosthesis. However, the time, cost and, technique sensitivity involved with computer-guided surgery impedes its routine practice. The aim of this study is to evaluate survival rates and complications associated with computer-guided versus conventional implant placement in implant-retained hybrid prostheses. Furthermore, long-term economic efficiency of this approach was assessed. METHODS: Patients were stratified according to implant placement protocol into a test group, using computer-guided placement, and a control group, using traditional placement. Calibrated radiographs were used to measure bone loss around implants. Furthermore, the costs of the initial treatment and prosthetic complications, if any, were standardized and analyzed. RESULTS: Forty-five patients (149 implants in the test group and 111 implants in the control group) with a minimum follow-up of 5 years, and a mean follow-up of 9.6 years, were included in the study. While no significant difference was found between both groups in terms of biologic and technical complications, lower incidence of implant loss was observed in the test group (P < 0.001). A statistically significant difference in favor of the non-guided implant placement group was found for the initial cost (P < 0.05) but not for the prosthetic complications and total cost (P > 0.05). CONCLUSIONS: Computer-guided implant placement for an implant-supported hybrid prosthesis is a valid, reliable alternative to the traditional approach for implant placement and immediate loading. Computer-guided implant placement showed higher implant survival rates and comparable long-term cost to non-guided implant placement.