Influence of modified titanium abutment surface on peri-implant soft tissue behaviour: A systematic review of histological findings

PURPOSE: The purpose of the present systematic review was to investigate at the histological level if a modified titanium surface abutment could affect the behaviour of soft peri-implant tissue (connective tissue adhesion and soft tissue inflammation). MATERIALS AND METHODS: An electronic databases research (MEDLINE/PubMed, Scopus, Web of Science, Cochrane Library) until 24 June 2019 for randomised controlled trials (RCTs), controlled clinical trials and non-randomised studies of interventions (NRSI) was performed. The focused question was: "In healthy patients with at least one titanium healing abutment connected to a dental implant, is the effect of a healing abutment surface modification different from machined titanium at the histological level?" The Cochrane Handbook for Systematic Reviews of Interventions to assess the risk of bias in individual studies was used for RCTs. The Newcastle-Ottawa quality assessment scale was used to evaluate NRSI. RESULTS: In total, 192 records were evaluated for titles and abstracts. Seven studies were included in the review. Five of them reported an enhanced soft tissue adhesion in the modified abutment group without increasing the soft tissue inflammation. One study reported no significant differences among titanium-modified (double acid-etched) and titanium-machined groups. One author demonstrated at the 6-month follow-up period a higher level of inflammation around acid-etched surfaces, with a higher number of T and B lymphocytes and expression of vascular endothelial growth factor. CONCLUSIONS: Short-term data (< 6 months) suggested an enhanced connective fibre attachment next to titanium abutments with a modified surface and a similar inflammatory response, in comparison with machined surface titanium abutments. However, modified surfaces may lead to a long-term increased risk of a higher degree of inflammation in the peri-implant tissues. Due to limited available evidence, further long-term studies are needed to confirm these results

What Are the Effects of Different Abutment Morphologies on Peri-implant Hard and Soft Tissue Behavior? A Systematic Review and Meta-Analysis

To evaluate the effect of different abutment morphologies on peri-implant hard and soft tissue behavior

Influence of abutment material and modifications on peri-implant soft-tissue attachment: A systematic review and meta-analysis of histological animal studies

Statement of problem. How the properties of the implant-abutment unit may affect the periimplant soft-tissue seal, whose stability is considered key to safeguarding the implant from bacterial contamination and preserve peri-implant health conditions, is unclear.Purpose. The purpose of this systematic review and meta-analysis of animal studies was to investigate whether material and surface properties of transmucosal implant components can influence the peri-implant soft-tissue adhesion at a histological level.Material and methods. An electronic and hand search was conducted until August 2019. Histological animal studies comparing soft-tissue response to abutment or transmucosal collar with different materials and/or surface characteristics were selected by 2 independent reviewers. Risk of bias in individual studies was evaluated. Histomorphometric data on the dimension of the peri-implant attachment were recorded, and a quantitative synthesis by a meta-analysis was performed. Risk of bias in individual studies was evaluated in accordance with the Systematic Review Centre for Laboratory Animal Experimentation Risk of Bias tool.Results. Eighteen relevant studies out of 1187 were identified, none with a low risk of bias for all domains. Data from only 4 studies could be meta-analyzed. Comparable results in terms of periimplant attachment dimensions between test and control groups were found, except for a significantly higher apical junctional epithelium to coronal bone to implant (ajE-CBI) distance for chemically modified acid-etched compared with titanium machined surfaces. Non-meta-analyzable and/or qualitative results highlighted some improved properties also for microgrooved and oxidized surfaces.Conclusions. Limited data from animal studies suggest that some characteristics of the transmucosal implant components may affect peri-implant soft-tissue adhesion and stabilization but do not allow definitive conclusions. Future research should improve study design to increase the availability of comparable and suitable data on this topic

Autogenous graft versus collagen matrices for peri-implant soft tissue augmentation. A systematic review and network meta-analysis.

OBJECTIVE The primary objective of this review is to compare autogenous soft tissue grafts (connective tissue graft - CTG and free gingival graft-FGG) with different type of matrices (acellular dermal matrix-ADM, xenograft collagen matrix-XCM, volume-stable collagen matrix-VCMX) used to increase peri-implant soft tissues. MATERIALS AND METHODS A search on electronic databases was performed to identify randomized and non-randomized controlled trials (RCTs and CCTs, respectively) with either parallel or split-mouth design, and treating ≥ 10 patients. A network meta-analysis (NMA) was used to compare different matrices. Soft tissue thickness dimensional changes and keratinized width (KMW) changes were the primary outcome measures. The secondary outcomes were to evaluate: a) PROMs; b) volumetric changes; c) surgical operating time; and d) different periodontal measurements. RESULTS A total of 23 studies were included in the qualitative analysis, and 16 studies (11 RCTs and 5 CCTs) in the quantitative analysis. A total of N = 573 sites were evaluated for NMA. CTG resulted the best material for increasing peri-implant soft tissue thickness, at 180 and 360 days after surgery. The use of an ADM showed good results for buccal thickness increase, primarily in the first three months after surgery. Vestibuloplasty + FGG resulted in the most effective technique for peri-implant KMW augmentation, after 180 days. CONCLUSIONS While CTG demonstrated better performance in all the comparison and FGG showed to be the best graft to increase keratinized mucosa up to 90 days, ADM and VCMX may be used to increase soft tissue horizontal thickness with lower patients' morbidity. LIMITATIONS The limits of this NMA are the following: a) limited number of included studies; b) high heterogeneity among them (number of patients, treatment sites, surgical techniques, outcome measures, and follow-ups). CLINICAL RELEVANCE Many studies compared the efficacy of autogenous and non-autogenous grafts in terms of gingival thickness, volume, and keratinized width increase. However, there is still not clear overall evidence on this topic. This NMA helps clinicians to choose the right material in different peri-implant soft tissue procedures. Recommendations for future studies are mandatory

Minimal invasiveness in vertical ridge augmentation

Vertical ridge augmentation is one of the most challenging procedures in implant dentistry because of the advanced skills required by the operator and the fact that bone augmentation is aimed outside the bony contour, in an environment of reduced blood supply. What is more, the flap management required to ensure soft tissue closure frequently leads to associated comorbidities in terms of swelling and hematomas. For these reasons, and even if autologous onlay block grafts are still the gold standard, new techniques and biomaterials have favored the development of potentially less invasive approaches. The present work evaluates the most recent strategies in vertical ridge augmentation to reduce invasiveness and complications, including diagnostic/treatment planning considerations, surgical techniques, digital tools (eg, customized titanium meshes/membranes or bone blocks), and future trends in the field of tissue engineering and cell therapy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/176894/1/prd12479.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/176894/2/prd12479_am.pd

Soft tissue dimensional changes after alveolar ridge preservation using different sealing materials: a systematic review and network meta-analysis.

BACKGROUND Alveolar ridge preservation (ARP) is a proactive treatment option aiming at attenuating post-extraction hard and soft tissue dimensional changes. A high number of different types of biomaterials have been utilized during ARP to seal the socket, but their effectiveness in terms of soft tissue outcomes has rarely been investigated and compared in the literature. OBJECTIVE To evaluate the efficacy of different types of membranes and graft materials in terms of soft tissue outcomes (keratinized tissue width changes, vertical buccal height, and horizontal changes) after ARP, and to assign relative rankings based on their performance. MATERIALS AND METHODS The manuscript represents the proceedings of a consensus conference of the Italian Society of Osseointegration (IAO). PUBMED (Medline), SCOPUS, Embase, and Cochrane Oral Health's Information Specialist were utilized to conduct the search up to 06 April 2021. English language restrictions were placed and no limitations were set on publication date. Randomized controlled trials that report ARP procedures using different sealing materials, assessing soft tissue as a primary or secondary outcome, with at least 6-week follow-up were included. Network meta-analysis (NMA) was performed using mean, standard deviation, sample size, bias, and follow-up duration for all included studies. Network geometry, contribution plots, inconsistency plots, predictive and confidence interval plots, SUCRA (surface under the cumulative ranking curve) rankings, and multidimensional (MDS) ranking plots were constructed. RESULTS A total of 11 studies were included for NMA. Overall, the level of bias for included studies was moderate. Crosslinked collagen membranes (SUCRA rank 81.8%) performed best in vertical buccal height (VBH), autogenous soft tissue grafts (SUCRA rank 89.1%) in horizontal width change (HWch), and control (SUCRA rank 85.8%) in keratinized mucosa thickness (KMT). CONCLUSIONS NMA confirmed that the use of crosslinked collagen membranes and autogenous soft tissue grafts represented the best choices for sealing sockets during ARP in terms of minimizing post-extraction soft tissue dimensional shrinkage. CLINICAL RELEVANCE Grafting materials demonstrated statistically significantly better performances in terms of soft tissue thickness and vertical buccal height changes, when covered with crosslinked collagen membranes. Instead, soft tissue grafts performed better in horizontal width changes. Non-crosslinked membranes and other materials or combinations presented slightly inferior outcomes

Sealing materials for post-extraction site: a systematic review and network meta-analysis.

AIM By means of a systematic review and network meta-analysis, this study aims to answer the following questions: (a) does the placement of a biomaterial over an extraction socket lead to better outcomes in terms of horizontal and vertical alveolar dimensional changes and percentage of new bone formation than healing without coverage? And (b) which biomaterial(s) provide(s) the better outcomes? MATERIALS AND METHODS Parallel and split-mouth randomized controlled trials treating ≥ 10 patients were included in this analysis. Studies were identified with MEDLINE (PubMed), Embase, Cochrane Central Register of Controlled Trials, and Scopus. Primary outcomes were preservation of horizontal and vertical alveolar dimension and new bone formation inside the socket. Both pairwise and network meta-analysis (NMA) were undertaken to obtain estimates for primary outcomes. For NMA, prediction intervals were calculated to estimate clinical efficacy, and SUCRA was used to rank the materials based on their performance; multidimensional ranking was used to rank treatments based on dissimilarity. The manuscript represents the proceedings of a consensus conference of the Italian Society of Osseointegration (IAO). RESULTS Twelve trials were included in the qualitative and quantitative analysis: 312 sites were evaluated. Autologous soft tissue grafts were associated with better horizontal changes compared to resorbable membranes. A statistically significant difference in favor of resorbable membranes, when compared to no membrane, was found, with no statistically significant heterogeneity. For the comparison between crosslinked and non-crosslinked membranes, a statistically significant difference was found in favor of the latter and confirmed by histomorphometric NMA analysis. Given the relatively high heterogeneity detected in terms of treatment approaches, materials, and outcome assessment, the findings of the NMA must be interpreted cautiously. CONCLUSIONS Coverage of the healing site is associated with superior results compared to no coverage, but no specific sealing technique and/or biomaterial provides better results than others. RCTs with larger sample sizes are needed to better elucidate the trends emerged from the present analysis. CLINICAL RELEVANCE Autologous soft tissue grafts and membranes covering graft materials in post-extraction sites were proved to allow lower hard tissue shrinkage compared to the absence of coverage material with sealing effect. Histomorphometric analyses showed that non-crosslinked membranes provide improved hard tissue regeneration when compared to crosslinked ones

Consensus Report by the Italian Academy of Osseointegration on the Use of Graft Materials in Postextraction Sites

Purpose: After tooth extraction, a modeling and remodeling phase of bone and soft tissues occurs. It has been fully demonstrated that bone resorption as high as 50% can take place regarding ridge width and a variable amount concerning ridge height, making it difficult to perform implant surgery. Materials and Methods: Active members of the Italian Academy of Osseointegration (IAO) participated in this Consensus Conference, and three systematic reviews were conducted before the meeting to provide guidelines on alveolar ridge preservation procedures. The systematic reviews covered the following topics: (1) What material best preserves the dimensions of the ridge horizontally and vertically?; (2) what material favors the formation of the highest quantity of new bone?; (3) which technique would best seal the socket?; and (4) what effect does alveolar ridge preservation have on soft tissues? Results: The main conclusions reached by the assembly were that alveolar ridge preservation is advisable after dental extraction, particularly in esthetic areas, in proximity of anatomical structures (ie, maxillary sinus, inferior alveolar nerve, and mental foramen), whenever the treatment plan requires delayed placement, and whenever patients ask to postpone implant insertion for various reasons. Socket debridement is advised before the use of a "regenerative material," and xenograft is considered the gold standard material to maintain ridge dimensions. Another indication is antibiotic therapy, which is recommended in the case of alveolar ridge preservation (amoxicillin 2 g 1 hour before the intervention and 1 g every 12 hours for 6 days). A membrane or autologous soft tissue should be used to seal the socket and protect the regenerative material, and the indicated reentry time (implant insertion) is 4 to 6 months. Conclusion: This Consensus Conference agreed that the adoption of alveolar ridge preservation can effectively prevent physiologic bone loss, especially in esthetic areas. It is recommended to cover the xenograft material with a membrane or autologous soft tissue, and antibiotic therapy is advisable