Soft tissue augmentation procedures at second-stage surgery: a systematic review

Biofunctionalization of silk fibroin scaffolds with enamel matrix protein and injectable platelet rich fibrin for soft tissue augmentation: an in-ovo study

PURPOSE

Silk fibroin (SF) is a biomaterial derived from the cocoon of the mulberry silkworm. This study aimed to assess the capacity of SF matrices biologized with injectable platelet-rich fibrin (iPRF) or enamel matrix protein (EMP) to modulate angiogenesis and immune response in the chorioallantoic membrane (CAM) assay.

METHODS

300 eggs were divided into the following groups: CM + NaCl, CM + iPRF, CM + EMP, SF + NaCl, SF + iPRF, and SF + EMP. Matrices were applied to the CAM on embryonic development day (EDD) 7 after rehydration. Angiogenesis, represented by vascularized area, vessel density, and vessel junctions, was evaluated on EDD 10, 12, and 14. Additionally, gene expression of HIF-1ɑ, VEGF, MMP-13, and NOS2 was assessed via quantitative polymerase chain reaction (qPCR) on EDD 11 and 14.

RESULTS

The number of vascularized specimens was notably higher in SF matrices regardless of the treatment applied, while in the CM group, only matrices biofunctionalized with iPRF demonstrated vascularization. On EDD 14, the CM + iPRF group exhibited the highest values for total vascularized area (CM + iPRF: 57.52%, SF + iPRF: 21.87%, p < 0.001), vessel density (CM + iPRF: 0.0067 μm/µm2, SF + iPRF: 0.0032 μm/µm2, p = 0.002), number of vessel junctions (CM + iPRF: 14.45, SF + iPRF: 4.82, p = 0.001). Gene expressions displayed high data variability and no significant differences between the groups.

CONCLUSIONS

Biofunctionalization with iPRF in CM leads to a high vascularization rate probably through their capability of retaining higher liquid volumes, suggesting improved intraoral wound healing after guided tissue regeneration (GTR). Despite biofunctionalization, SF matrices exhibit a high vascularization, indicating SF as a promising material for GTR.

Enhancing Implant Success in Mandibular Reconstruction: A Novel Approach Combining Implant-Retained Splint and Vestibuloplasty-A Case Series

Background: Mandibular reconstruction poses challenges in achieving functional and aesthetic outcomes. Effective oral rehabilitation is crucial for restoring function and improving quality of life; however, the altered neomandibular anatomy complicates oral hygiene, increasing the risk of peri-implant complications and making successful rehabilitation more difficult. This study introduces a novel approach combining vestibuloplasty with patient-specific implant-retained splints to enhance oral health and improve rehabilitation outcomes. Methods: Three patients underwent mandibular reconstruction with a free vascularized fibula flap (FFF). After 6 months of osseointegration, vestibuloplasty and soft tissue refinement were performed, with a split-thickness skin graft placed on the FFF periosteum. An implant-retained splint was secured to the abutments for two weeks to support soft tissue healing. Implant survival, bone loss, and peri-implant health were evaluated over a 2-year follow-up. Results: A total of 12 implants were placed, primarily in the neomandible (83.3%), with a 100% survival rate. Implant survival was assessed. Implant survival was assessed based on established criteria for clinical success, including stability, presence of pain, bleeding on probing (BOP), pocketdepth, bone loss and lack of peri-implant radiolucency. Functional outcomes included normal mouth opening, laterotrusion, and protrusion. Pocket depths ranged from 3 to 4 mm, except for one implant in cases 1 and 2. The mean BOP was 51.7%. Conclusions: This case series introduces a surgical technique that combines CAD/CAM and vestibuloplasty to optimize dental rehabilitation in mandibular FFF reconstructions, demonstrating safe thinning of soft tissues for improved oral hygiene and survival.

Socket Preservation Using Platelet-Rich Fibrin and Free Gingival Grafts

OBJECTIVE

The present randomised controlled trial is based on the null hypothesis that there is no difference in crestal bone levels (CBLs) following socket preservation (SP) using platelet-rich fibrin (PRF) and free gingival graft (FGG). The aim was to evaluate CBLs following SP using PRF and FGG.

METHODS

This study is a parallel-arm randomised controlled trial. Patients in the test and control groups underwent SP using PRF and FGG, respectively. Intraoral visual examination was performed to clinically assess signs of swelling, pus/abscess, and stability of sutures and graft. Self-rated postoperative pain was assessed after 1 week and 6 months using the visual analogue scale (VAS). At the 6-month follow-up, cone-beam computed tomography was performed to evaluate CBL in mesiodistal and buccolingual dimensions. The preoperative cone-beam computed tomographic images were superimposed with those taken at the 6-month follow-up to compare CBLs. Statistical comparisons were performed and level of significance was set at P < .05.

RESULTS

The test and control groups each comprised 13 individuals with comparable ages. All teeth included in the test and control groups were located in the maxillary aesthetic zone. At the 1-week follow-up, VAS scores were higher in the control than in the test group (P < .01). At the 6-month follow-up, none of the participants reported self-rated pain. The change in buccolingual dimension was greater in the control group than in the test group (P < .05).

CONCLUSIONS

Both FGG and PRF are effective techniques for SP; however, the latter technique is more effcacious in maintaining buccolingual dimensions of the extraction socket.

Effect of free gingival graft dimension on postsurgical shrinkage in posterior implant placement: A prospective parallel cohort study

STATEMENT OF PROBLEM

The impact of free gingival graft (FGG) dimensions on the postsurgical shrinkage of keratinized tissue width (KTW) and surface area in posterior implant sites is unclear. Standardized assessments of how graft dimensions influence KTW and surface area shrinkage rates over a 6-month period after FGG are lacking.

PURPOSE

The purpose of this prospective parallel cohort study was to examine the impact of the graft dimensions on the postsurgical shrinkage of KTW and surface area over a 6-month follow-up period after FGG in the posterior regions.

MATERIAL AND METHODS

Thirty partially edentulous participants with insufficient buccal KTW in the posterior regions were recruited. Before implant placement, participants received FGG procedures and were categorized into single-tooth and dual-tooth groups according to the range of recipient area. Intraoral scanning was performed before and after FGG and at subsequent follow-ups for 6 months. The KTW and surface area shrinkage rates of the grafted area were calculated and statistically analyzed by using the Student t test and ANOVA, and Bonferroni post hoc tests were performed to compare the shrinkage rate of KTW at various edentulous sites (α=.05).

RESULTS

The mean ±standard deviation KTW shrinkage rate was 18.84 ±5.11% over 6 months postoperatively, and the mean ±standard deviation SA shrinkage rate was 21.53 ±5.70%. The dual-tooth group had a statistically significantly higher KTW shrinkage rate (28.42 ±2.46%) when the second molar edentulous sites were involved (P<.05). Differences in surface area shrinkage rates between the single-tooth and dual-tooth groups over 6 months were statistically similar (P=.239). However, grafts in the second molar area exhibited significantly higher surface area shrinkage rates compared with those at the premolar and first molar areas (P<.001).

CONCLUSIONS

The dimension of free gingival graft tissues did not significantly affect surface area shrinkage rates, and a mean 25% shrinkage rate occurred in the second molar areas.

Effectiveness of keratinized mucosa augmentation procedures around dental implants based on risk assessment: A 5-year retrospective cohort study

PURPOSE

To compare the effectiveness of keratinized mucosa (KM) augmentation with different techniques for the treatment of dental implants based on risk assessment.

METHODS

Thirty-nine patients who underwent KM augmentation at implant sites in the posterior mandible were included. Three techniques were used based on anatomy-guided risk assessment: an apically positioned flap (APF) alone, an APF plus a free gingival graft (APF plus FGG), and an APF plus a collagen matrix (APF plus CM). Clinically effective KM augmentation was defined as remaining KM ≥ 2 mm after the intervention. The effective rate, implant/prosthesis survival rates, and bone/soft tissue parameters were analyzed. The correlation between local anatomical characteristics and different techniques was also determined. The associations between the effectiveness of KM augmentation and related factors were analyzed using a linear model.

RESULTS

Overall, 74 sites received KM augmentation in the posterior mandible, for an effective rate of 94.6% at the 1-year follow-up and 93.2% at the 5-year follow-up. The KM width in the APF plus FGG group (3.85 ± 1.22 mm) was greater than that in the APF alone (3.05 ± 0.90 mm) (P = 0.016) and APF plus CM (3.21 ± 1.17 mm) groups (P = 0.038) at 5 years post-surgery. There was no significant difference in the effective/ineffective outcomes at the 1-year or 5-year follow-up among the three groups.

CONCLUSIONS

Comparable effective outcomes were achieved with three KM augmentation techniques following the decision-making criterion based on risk assessment.

Management of Soft Tissue Defects Around Single Implants: A Systematic Review of the Literature

OBJECTIVES

The aim of this systematic review was to assess the effectiveness of the available techniques for the management of peri-implant soft tissue defects around single implants in the anterior region.

MATERIAL AND METHODS

A comprehensive search was conducted in PubMed (MEDLINE), Web of Science (all databases), and Cochrane, using keywords and MeSH terms related to the topic. This systematic review included prospective interventional studies with a minimum of 10 patients and at least 6 months of follow-up.

RESULTS

A total of 13 articles were included, with eight focusing on outcomes related to buccal soft tissue dehiscence coverage procedures and the remaining five investigating interventions aimed at augmenting soft tissue thickness. Coronally advanced flap in combination with connective tissue graft was the most effective technique for buccal soft tissue dehiscence coverage in the medium and long term. In terms of increasing soft tissue thickness, both connective tissue graft and acellular dermal matrix demonstrated satisfactory short-term outcomes; however, their long-term efficacy remains unclear.

CONCLUSIONS

Soft tissue augmentation procedures resulted in satisfactory outcomes, in terms of buccal soft tissue dehiscence coverage and soft tissue thickness increase, around single implants in the esthetic area. Peri-implant plastic surgery has improved both the esthetic appearance and quality of life of patients.

PROSPERO REGISTRATION CODE

CRD42023398424.

Xenogeneic Collagen Matrix Versus Free Gingival Graft for Augmenting Peri-Implant Keratinized Mucosa Around Dental Implants: A Systematic Review and Meta-Analysis

OBJECTIVES

There is a growing evidence to suggest augmenting peri-implant keratinized mucosa in the presence of ≤ 2 mm of keratinized mucosa. However, the most appropriate surgical technique and augmentation materials have yet to be defined. The aim of this systematic review and meta-analyses was to evaluate the clinical and patient-reported outcomes of augmenting keratinized mucosa around implants using free gingival graft (FGG) versus xenogeneic collagen matrix (XCM) before commencing prosthetic implant treatment.

MATERIAL AND METHODS

Electronic databases were searched to identify observational studies comparing implant sites augmented with FGG to those augmented with XCM. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool.

RESULTS

Six studies with 174 participants were included in the present review. Of these, 87 participants had FGG, whereas the remaining participants had XCM. At 6 months, sites augmented with FGG were associated with less changes in the gained width of peri-implant keratinized mucosa compared to those augmented with XCM (mean difference 1.06; 95% confidence interval -0.01 to 2.13; p = 0.05). The difference, however, was marginally significant. The difference between the two groups in changes in thickness of peri-implant keratinized mucosa at 6 months was statistically significantly in favor of FGG. On the other hand, XCM had significantly shorter surgical time, lower postoperative pain score, and higher color match compared to FGG.

CONCLUSIONS

Within the limitation of this review, the augmentation of keratinized mucosa using FGG before the placement of the final prosthesis may have short-term positive effects on soft tissue thickness. XCM might be considered in aesthetically demanding implant sites and where patient comfort or shorter surgical time is a priority. The evidence support, however, is of low to moderate certainty; therefore, further studies are needed to support the findings of the present review.

Novel digital technique for measuring the volumetric healing process of free gingival grafts surrounding dental implants

The objective of the present study was to analyze and describe a new digital technique for analyzing the volumetric healing process of free gingival grafts in both donor and recipient locations surrounding a dental implant, as well as to compare the reliability of conventional and digital techniques for measuring the width of the free gingival graft in the recipient location throughout the healing process.

Materials and methods

Ten patients presenting with mucositis linked to a dental implant were included. A preoperative soft tissue width <2 mm, with probing pocket depth <5 mm, edema and inflammation and bleeding on probing was determined A digital impression was taken of both donor and recipient locations using an intraoral scan, generating a Standard Tessellation Language digital file both preoperatively (STL1) and after 1 week (STL2), 1 month (STL3), 3 months (STL4), and 6 months (STL5) of follow-up. Afterwards, the digital files (STL1-STL5) were aligned using a reverse engineering morphometric software, and Student's t-test was used to analyze changes in volume at the donor and recipient locations. Additionally, widths were measured both clinically and digitally so as to compare the reliability of these measurement techniques. The repeatability and reproducibility of both these measurement techniques were also analyzed using Gage R&R statistical analysis.

Results

Gage R&R found that the total variability of the digital technique was 0.6% (among the measures of each operator) and 7.6% (among operators); as variability was under 10%, the results were repeatable and reproducible. In addition, there were statistically significant differences between donor and recipient locations in healing process volume (mm3) after one week (p = 0.0110), one month (p = 0.0007), three months (p < 0.0001) and six months (p = 0.0004) of follow-up.

Conclusion

The digital measurement technique provided accurate, repeatable, and reproducible results when analyzing the volumetric and linear measures of the healing process in both the donor and recipient locations of a free gingival graft surrounding a dental implant, with significantly higher tissue volume in the recipient location.

Soft tissue management around dental implant in esthetic zone - the current concepts and novel techniques

It has been said, 'Bone sets the tone, but tissue is the issue.' In the field of implantology, while significant breakthroughs have been achieved in hard tissue regeneration, clinicians find it more challenging to handle soft tissue complications around dental implants. Successfully managing soft tissue around dental implants requires clinicians to have comprehensive knowledge of proper implant placement, prosthetic design and tissue management, and a high level of surgical skills for soft tissue augmentation and grafting. Autogenous gingival grafts can be utilized in various clinical situations, providing surgeons with great potential and freedom to enhance the quality and quantity of peri-implant soft tissue. Emerging trends, such as digital tools for treatment planning, minimally invasive surgical approaches, and innovative biomaterials, can also contribute to a more pleasing outcome. By elucidating these multifaceted considerations, this review will serve as a valuable resource for clinicians aiming to achieve functional and aesthetic excellence in implant-based oral rehabilitation.

Soft-tissue augmentation for increasing keratinized tissue around dental implants: A systematic review

Background

This systematic review aims to comprehensively assess the efficacy of soft-tissue augmentation procedures in enhancing the width of keratinized mucosa (KM) surrounding implants with compromised soft-tissue status.

Materials and Methods

A thorough search was conducted on MEDLINE through PubMed and EMBASE via Ovid, supplemented by manual article searches. Inclusion criteria comprised human studies published in English within the past decade (up to July 2023), focusing on soft-tissue grafting techniques for augmenting keratinized mucosal width. The Joanna Briggs Institute critical appraisal tools were employed to evaluate the risk of bias in selected studies.

Results

The review includes 27 studies, comprising nine prospective clinical studies, 13 randomized controlled trials (RCTs), and 5 case series. Notably, interventions demonstrated an augmented KM ranging from 0.89 mm to 7.7 mm. Optimal outcomes were observed with apically positioned partial-thickness flaps and vestibuloplasty (VP) utilizing xenogeneic collagen matrix (XCM) or free gingival graft (FGG). However, heterogeneity in study designs precluded meta-analysis.

Conclusion

Despite the limitations, this study emphasizes the potential to augment KM width through apically positioned partial-thickness flaps and VP techniques employing XCM or FGG. Further RCTs with extended follow-up are needed to refine treatment approaches, improve outcomes, and address gaps in understanding graft integration mechanisms and strategies to minimize graft shrinkage.

The Significance of Keratinized Mucosa in Implant Therapy: Narrative Literature Review and Case Report Presentation

Background/Objectives: Implant treatment in patients who require teeth extraction due to periodontitis presents a significant challenge. The consideration of peri-implantitis is crucial when planning the placement of dental implants. The predictability of implant treatment relies on the suitability of both hard and soft tissue quality. The aim of this article is to present a case report demonstrating a secure treatment protocol for implant procedures in patients with periodontitis requiring the extraction of all teeth, soft tissue management targeted at increasing the keratinized mucosa zone, and the provision of a reliable prosthetic solution. The secondary objective is to review the relevant literature regarding the significance of keratinized mucosa surrounding dental implants and its association with the occurrence of peri-implantitis. Case presentation: A 65-year-old female with generalized periodontitis, stage IV grade C and very poor oral hygiene came for treatment and rehabilitation of the lower jaw. CBCT revealed periodontal lesions and labio-lingual ridge dimensions in the region of teeth 34-44 from 8.0 to 10.2 mm. The first surgery included teeth extraction and periodontal lesions enucleation with simultaneous placement of four implants in the positions of teeth 32, 34, 42, 44. The second-stage surgery involved increasing the keratinized mucosa using two free gingival grafts. Conclusions: The present case report described the treatment process of the patient with periodontitis, including immediate implantation in the infected region, soft tissue augmentation using free gingival grafts and the ultimate placement of a bar-retained overdenture for final restoration. After two years of observation, despite questionable hygiene, no symptoms of gingival inflammation were detected. Furthermore, there is limited information in the literature regarding the correlation between inadequate keratinized gingiva and the occurrence of peri-implantitis.

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.

Bone assessment around the delayed dental implant with and without preformed anatomical caps: A 1-year retrospective case-control study

PURPOSES

To investigate the amount of first-year peri‑implant bone loss and the development of the papillae when delayed dental implants loaded with anatomic cover screw and those underwent conventional healing protocol were compared.

METHODS

Edentulous healed sites had undergone delayed implants placement. In the anatomical cap group, patients were treated with a guided tissue healing, tooth-like cross-linkable acrylic resin caps had been immediately screwed on dental implants. The marginal loss of the alveolar bone height 1 year after surgery and Jemt's papillae index were obtained. Non-parametric statistics were performed with a level of significance of 1% RESULTS: Forty patients were included in the present retrospective analysis. After a follow-up of 1 year, none of the 40 included implants showed a failure. The Jemt's papilla index was 1.76±0.44 and 1.34±0.50 respectively for guided tissue healing and conventional healing group, without any significant difference. Within the first year of survey a bone loss of -1.27±0.26 mm for conventional healing treatment showed a statistically significant difference (p-value<0.0001) when it was compared to the negligible of the other group (-0.06±0.31 mm).

CONCLUSIONS

A guided healing procedure with preformed caps seemed to give better outcomes regarding marginal bone loss and papilla index than those of conventional abutments.

Comparative analysis of xenogeneic collagen matrix and autogenous subepithelial connective tissue graft to increase soft tissue volume around dental implants: a systematic review and meta-analysis

OBJECTIVE

The gold standard for a soft tissue augmentation around implants is a subepithelial connective tissue graft (CTG), but the xenogeneic collagen matrices (XCM) started to be used as an alternative. This systematic review aimed to assess the effectiveness XCM in comparison to CTG for the increasing the thickness of the soft tissue around implants.

DATA

All studies included at least two parallel groups comparing the use of CTG and XCM with a minimum follow-up of 3 months. As the primary outcome, the amount of soft tissue thickness gain after soft tissue augmentation with XCM or CTG was assessed. Secondary outcomes were clinical and patient-related outcomes; evaluation of aesthetic outcomes, patient-reported outcomes measures (PROMs) and complications. Eligible studies were selected based on the inclusion criteria. Meta-analysis was applied whenever possible. The quality of the evidence of studies including in meta-analysis was assessed using the GRADE approach.

SOURCE

A systematic literature search up to January 2022 was conducted using the following electronic databases: PubMed (MEDLINE), Scopus, Cochrane Library, LILACS, eLIBRARY.RU. Unpublished researches, the gray literature, nonprofit reports, government studies and other materials were reviewed electronically using an EASY search. An additional manual search was carried out in November 2022.

STUDY SELECTION

Of the 1376 articles from the initial search, 8 randomized controlled trials (RCTs) (306 patients and 325 implants) were included in this systematic review, and 7 studies were part of the meta-analysis. Meta-analysis revealed that XCM is less effective than the CTG in increasing soft tissue thickness around dental implants. However, XCM also provides soft tissue thickness gain and can be recommended for use in various clinical situations.

CLINICAL SIGNIFICANCE

Previous systematic reviews and meta-analyses have shown that autologous grafts are more effective than collagen matrices in increasing soft tissue thickness, however, the latter can be used as an alternative. Studies included in previous systematic reviews varied in design, which could lead to limitations. The present systematic review and meta-analysis includes for the first time only randomized controlled clinical trials with collagen matrix of xenogeneic origin in the test group. Tight eligibility criteria were established, and the main parameter studied was soft tissue thickness. It was found that xenogeneic collagen matrix is effective for increasing soft tissue thickness around dental implants, however, the results obtained using an autogenous connective tissue graft are superior.

The "White Layer Approach": A Graftless Gingival Augmentation Technique following Vertical GBR with Occlusive Titanium Barriers

Guided bone regeneration surgery always leads to a deformation of the soft tissues consequent to passivation of the flap. In this article, a graftless technique for the restoration of the vestibular depth and for the augmentation of adherent soft tissue, called the "white layer approach", is proposed after a vertical GBR procedure in posterior areas. Six patients (five males and one female) with vertical bone atrophy were enrolled in the study and underwent three-dimensional bone augmentation with titanium barriers. After 6 months, during the second-stage surgery, a 0.5 mm thick layer of white pseudo-periosteum was observed underneath the titanium barrier and over the newly formed bone. The buccal portion of the pseudo-periosteum was left intentionally exposed, in order to promote the spontaneous formation of new adherent gingiva and the restoration of the original depth of the fornix. The implant insertion was then planned 3 months after the WLA in a conventional procedure. The buccal adherent soft tissue height was measured from the crestal point to the most apical point, using a periodontal probe, before the barrier removal at 3 months after the white layer approach (WLA). In all patients, a gain in adherent soft tissue varying from 5 to 8 mm was observed; the average adherent soft tissue gain (ASTG) was 6.75 mm. The vertical bone height was measured by CT scans at baseline and before the implant placement, and showed an average vertical bone gain (AVBG) of 4.08 mm. Within the limitations of this study, vertical GBR with titanium occlusive barriers (OTB) associated with the white layer approach (WLA) may represent a simplified technique for hard and soft tissue augmentation in posterior areas, even without a free gingival graft.

Interdisciplinary Management of Bilateral Congenital Lateral Incisor Agenesis

Management of lateral incisor agenesis is a real challenge and needs a strong collaboration between surgical, aesthetic, and orthodontic dentistry. This case report managed upper lateral incisor agenesis with an orthodontic treatment leading to open spaces and placement of cuspids in lateral incisor area to avoid implant placement in maxillary anterior region. Temporary rehabilitation phase, using resin injected tray and removable partial denture, has been placed to maintain mesiodistal dimensions and restore aesthetic during pre-implant analysis and osseointegration. Once osseointegration was fully obtained, keratinized tissue augmentation has been obtained using connective tissue graft. Then, temporary implant fixed crowns allowed soft tissue modeling during interim rehabilitation. Finally, screw-retained permanent crowns were placed to fully restore aesthetic and function. This case goal was to optimize final results and reach patient complete satisfaction using orthodontic treatment combined with implant rehabilitation, and coupled with interdisciplinary management and well-time sequencing treatment.

Three-dimensional changes of a porcine collagen matrix and free gingival grafts for soft tissue augmentation to increase the width of keratinized tissue around dental implants: a randomized controlled clinical study

BACKGROUND

Emerging clinical data points to the relevance of the presence of keratinized tissue (KT). Although apically positioned flap/vestibuloplasty along with free gingival graft (FGG) is considered as a standard intervention for augmenting KT, substitute materials appear to be a viable treatment alternative. So far, there is a lack of data investigating the dimensional changes at implant sites treated with soft-tissue substitutes or FGG.

AIM

The present study aimed at comparing three-dimensional changes of a porcine derived collagen matrix (CM) and FGG for increasing KT at dental implants over a 6-month follow-up period.

MATERIALS AND METHODS

The study enrolled 32 patients exhibiting deficient KT width (i.e., < 2 mm) at the vestibular aspect who underwent soft tissue augmentation using either CM (15 patients/23 implants) or FGG (17 patients/31 implants). The primary outcome was defined as tissue thickness change (mm) at treated implant sites between 1- (S0), 3- (S1), and 6-months (S2). Secondary outcomes considered changes of KT width over a 6-month follow-up period, surgical treatment time, and patient-reported outcomes.

RESULTS

Dimensional analyses from S0 to S1 and from S0 to S2 revealed a mean decrease in tissue thickness of - 0.14 ± 0.27 mm and - 0.04 ± 0.40 mm in the CM group, and - 0.08 ± 0.29 mm and - 0.13 ± 0.23 mm in the FGG group, with no significant differences noted between the groups (3 months: p = 0.542, 6 months: p = 0.659). Likewise, a comparable tissue thickness decrease was observed from S1 to S2 in both groups (CM: - 0.03 ± 0.22 mm, FGG: - 0.06 ± 0.14 mm; p = 0.467). The FGG group exhibited a significantly greater KT gain after 1, 3 and 6 months compared to the CM group (1 month: CM: 3.66 ± 1.67 mm, FGG: 5.90 ± 1.58 mm; p = 0.002; 3 months: CM: 2.22 ± 1.44; FGG: 4.91 ± 1.55; p = 0.0457; 6 months: CM: 1.45 ± 1.13 mm, FGG: 4.52 ± 1.40 mm; p < 0.1). Surgery time (CM: 23.33 ± 7.04 min.; FGG: 39.25 ± 10.64 min.; p = 0.001) and postoperative intake of analgesics were significantly lower in the CM group (CM: 1.2 ± 1.08 tablets; FGG: 5.64 ± 6.39 tablets; p = 0.001).

CONCLUSIONS

CM and FGG were associated with comparable three-dimensional thickness changes between 1 and 6 months. While a wider KT band could be established with FGG, the use of CM significantly reduced surgical time and patients´ intake of analgesics.

Soft tissue phenotype modification impacts on peri-implant stability: a comparative cohort study

OBJECTIVES

Soft tissue phenotype modification (STPM) could be performed to maintain peri-implant health. Therefore, the aim of the study was to analyze tissue alteration around implants following soft tissue phenotype modification during implant uncovering surgery.

MATERIALS AND METHODS

Patients who had STPM (either pouch roll or modified roll technique) during implant second-stage surgery with at least 12-month follow-up were included. Clinical and radiographic parameters including mucosal tissue thickness (MTT), recession (REC), keratinized mucosa width (KMW), probing pocket depth (PPD), marginal bone loss (MBL), emergence profile, and emergence angle were extracted from 2-week, 2-month, and 12-month visits after second-stage surgery.

RESULTS

Twenty-eight patients with 33 implants that fulfilled the inclusion criteria were included. After soft tissue phenotype modification, at 2 weeks, REC was negatively correlated to mean MTT at mid-buccal site (r =  - 0.41, p = 0.018) and borderline correlated at mid-lingual site (r =  - 0.343, p = 0.051). Stable KMW was maintained from 2 weeks to 12 months with minimal shrinkage rate (3 ~ 14%). MBL change was limited (0.24 ~ 0.47 mm) after STPM. All implants had shallow PPD (≤ 3 mm) with the absence of bleeding on probing. Emergence angle at the mesial side, however, was significantly correlated to surgical techniques, which indicated pouch roll technique would have 6.96 degrees more than modified roll technique (p = 0.024).

CONCLUSIONS

Soft tissue phenotype modification, either pouch roll or modified roll technique, during uncovering surgery resulted in favorable clinical outcomes. Thin mucosal tissue thickness and pouch roll technique are the factors related to more recession at 2 weeks. Pouch roll technique could influence the restorative design by having a wide emergence angle at the mesial side.

CLINICAL RELEVANCE

Modified and pouch roll techniques during uncovering surgery were viable methods to yield favorable peri-implant health, while the preciseness of pouch roll technique was required to avoid mucosal recession and inadequate restorative design.

Soft-Tissue Augmentation around Dental Implants with a Connective Tissue Graft (CTG) and Xenogeneic Collagen Matrix (CMX)-5-Year Follow-Up

Proper horizontal and vertical thickness of the gingival connective tissue has been proven to be one of the success criteria in dental implant and reconstructive surgery. When thin tissue is found, gingiva augmentation methods can be used to increase the quality and volume of the tissue. Many methods have been described, among them pedicle soft-tissue flaps or autogenic tissue grafts. As an alternative to patients' own tissue, xenogenic materials can be used for grafting. The fundamental issue is to choose a material that will ensure the maximum therapeutic effect, while also minimizing the negative influence on the patient's health. The aim of this study was to compare gingival augmentation procedures using a palatal connective tissue graft (CTG) and an xenogenic soft-tissue substitute, Geistlich Mucograft (xenogeneic collagen matrix; CMX), and assess whether the timing of the graft surgery influences the clinical outcomes. The original study was a randomized control trial with a total of 75 implants placed. The patients received the soft-tissue thickening 3 months before the implant placement or 3 months after the implant placement (depending on the group). A connective tissue graft (CTG) or Geistlich Mucograft were used (depending on the group). For both the CTG and Geistlich Mucograft, better clinical outcomes were observed for maintaining the alveolar bone level and the thickness of the attached gingiva compared to the control group with no gingival augmentation. The Geistlich Mucograft showed good clinical performance in comparison to the control. Soft-tissue augmentation with the CTG before the implant placement was found to be most efficient method in terms of a stable increase of the tissue thickness since, throughout the entire observation period, the greatest increase of 1.035 mm (SD = 0.73 mm) in thickness was observed. Statistically important differences in the tissue thickness baseline compared after 5 years were observed for groups G1 vs. G2b (no augmentation vs. CTG before), G1 vs. G3b (no augmentation vs. CTG after) and for groups G2b vs. G3a (CTG before vs. CMX after).

Xenogeneic collagen matrix versus free gingival graft for augmenting keratinized mucosa around posterior mandibular implants: a randomized clinical trial

OBJECTIVES

To assess the clinical efficacy of xenogeneic collagen matrix (XCM) plus apically positioned flap (APF) in augmenting the keratinized mucosa (KM) width (KMW) and thickness (KMT) around posterior mandibular implants and compare it with free gingival graft (FGG) plus APF.

MATERIAL AND METHODS

Thirty patients with KMW ≤ 2 mm in the posterior mandibular implant site were randomly allocated to the FGG group (FGG plus APF) or the XCM group (XCM plus APF). Clinical assessments, including KMW and KMT, shrinkage rate of established KM, and peri-implant soft tissue health, were evaluated during a 6-month follow-up. Additionally, the esthetic outcomes and patient-reported postoperative morbidity were investigated.

RESULTS

At 6 months, the KMW measured 3.60 ± 0.79 mm in the FGG group and 3.28 ± 0.96 mm in the XCM group (p = 0.186). Both groups showed a tendency for graft contraction (FGG, 42.11%; XCM, 53.22%). The KMT measured 1.24 ± 0.34 mm in the FGG group and 0.95 ± 0.29 mm in the XCM group, with statistical difference (p = 0.002). No difference in the peri-implant soft tissue health was observed between the two groups (p > 0.05), but the esthetic outcomes were better in the XCM group (p < 0.05).

CONCLUSIONS

XCM plus APF rendered a similar clinical efficacy in augmenting KMW as that with FGG plus APF, but with higher shrinkage. XCM plus APF was inferior with respect to FGG plus APF in augmenting KMT. The esthetic outcomes were better with XCM plus APF than FGG plus APF. Clinical relevance XCM plus APF graft was inferior with respect to FGG plus APF in augmenting KMT.

TRIAL REGISTRATION

Trial registration number: ChiCTR2200058027 and date: 03/27/2022.

Design of customized soft tissue substitutes for anterior single-tooth and posterior double-tooth defects: An in vitro study

OBJECTIVE

This study aims to validate the standardized procedure for designing soft tissue substitutes (STS) adapted to optimally fit single-tooth defects in the anterior jaws and double-tooth defects in the posterior jaw and to compare mathematically modeled average shapes.

MATERIALS AND METHODS

Casts from 35 patients with 17 single-tooth defects in anterior region and 21 double-tooth defects in posterior region were scanned. STS were designed and sectioned in 3D slices meshes. Thickness values were documented respecting mesial-distal and buccal-lingual orientations. Graphs were embedded into images, and hierarchical clustering was applied to group STS according to shape and thickness.

RESULTS

STS clustered into two groups per defect type. For anterior single defects, STS (n = 4) were either a small and thin oval: 7 mm buccal-lingual, 4-5 mm mesial-distal direction and 1.1-1.5 mm thick or a larger oval (n = 13): 9 mm buccal-lingual, 5-7 mm mesial-distal and 1.6 m thick. For posterior double tooth defects, STS (n = 10) were either narrow, long and thick: 6-7 mm buccal-lingual, 16-20 mm mesial-distal and 2.2 thick or a wide, thinner rectangle (n = 11): 9-11 mm buccal-lingual, 12-14 mm mesial-distal and 1.1-1.5 mm thick.

CONCLUSIONS

The study validated the standardized digital method to design grafts for soft tissue volume augmentation and identified four average shapes for anterior single-tooth and posterior double-tooth soft tissue defects.

CLINICAL SIGNIFICANCE

We developed and validated a standardized digital method to design an optimal geometrical shape of a soft tissue substitute for oral volume augmentation and combined it with mathematical modeling to identify average shapes for single-interior, and double-posterior tooth defects. The identified average shapes offer the possibility to produce better-fitted xenografts or synthetic STS blocks requiring minimal chair-side adaptation leading to reduced clinical time and patient discomfort and potentially improving soft tissue volume augmentation outcomes.

Comparison of acellular dermal matrix allografts and connective tissue autografts in soft-tissue augmentation around immediate implants: A pilot study

Background

Immediate implant has multiple advantages but does not prevent the reduction in dimension of the labial cortical plate due to bone remodelling and soft-tissue collapse along with gingival recession. This Randomised Controlled Trial (RCT) was carried out to evaluate the changes in peri-implant soft-tissue dimensions after the immediate implant along with soft-tissue augmentation with acellular dermal matrix and connective tissue autografts.

Methods

Twenty clinical cases requiring tooth extraction in the anterior region of the maxilla (single rooted tooth) were selected and randomly divided. An immediate implant with soft-tissue augmentation with acellular dermal matrix (group A) and connective tissue autografts (group B) was carried out. Clinical parameters such as thickness of the marginal gingiva (mm), width of the keratinized mucosa (KMW) (mm), dimensions of the interdental papilla between the implant and the adjacent teeth (mesial and distal) and gingival biotype around the implant at the baseline (before extraction of the tooth) and at 180 days (after implant placement during second-stage surgical exposure) were evaluated.

Results

The mean postoperative gingival thickness and KMW were statistically higher in group B than in group A. There was statistically significant intragroup decrease in papillary height in both the groups; however, intergroup change was insignificant. In both the groups, there was an increase in thickness of gingival tissue, but the gingival biotype remained thin.

Conclusion

Immediate implants augmented with connective tissue autografts showed an increase in thickness of the gingiva and KMW, reduced papillary collapse and improvement in tissue biotype as compared with the acellular dermal matrix.

Modified coronally advanced tunnel versus epithelialized free gingival graft technique in gingival phenotype modification: a comparative randomized controlled clinical trial

OBJECTIVES

The gingival thickness (GT) and keratinized tissue (KT) height are defined as the gingival phenotype. Both the modified coronally advanced tunnel technique (MCAT) and free gingival grafts (FGG) are used in modifying the gingival phenotype. This study aims to compare MCAT and FGG in gingival phenotype modification.

MATERIALS AND METHODS

One hundred and forty recessions in 50 patients with thin and insufficient keratinized tissue at the anterior mandible were treated with either MCAT or FGG. GT, KT height, recession depth, recession width, probing depth, and clinical attachment level were evaluated at baseline and 6 weeks, 6 months, and 12 months. GT change, KT change, root coverage (RC), clinical attachment gain, and complete root coverage (CRC) were calculated. The wound healing index, tissue appearance, patient expectations, aesthetic, and dentin hypersensitivity were assessed at baseline and 6 months.

RESULTS

All periodontal variables showed significant change from baseline to 12 months in both groups (p < 0.05). While FGG resulted in more KT change (p < 0.001), all MCAT sites showed at least 2 mm KT change in 12 months. MCAT resulted in greater GT change (p < 0.05) and RC (p < 0.003). In contrast, there was no significant inter-group CRC difference (p = 0.523). All patient-based variables were favorable to MCAT (p < 0.05), except dentin hypersensitivity (p = 0.225).

CONCLUSIONS

Both techniques were successful in terms of gingival phenotype modification in the anterior mandible. Additional GT increase, RC, and patient-based outcomes favored MCAT, though KT change proved greater with FGG.

CLINICAL RELEVANCE

Clinicians may choose MCAT for higher GT increase whereas FGG for more KTC.

TRIAL REGISTRATION NUMBER

NCT04690140 and date: 12/26/2020.

Management and prevention of soft tissue complications in implant dentistry

The management and prevention of soft tissue complications is of key importance in modern implant dentistry and influences biologic and esthetic outcomes. The assessment of the soft tissue conditions from a quantitative and qualitative perspective should, therefore, be part of the overall treatment plan. Such an assessment dictates a potential indication as well as an ideal time point for additional soft tissue management. A proper risk assessment and management of the soft tissues at the planned implant site are of key importance prior to any implant‐related surgery. Cases with peri‐implant soft tissue complications generally involve: (a) a lack of attached and keratinized mucosa; (b) insufficient volume; (c) development of mucosal dehiscences; or (d) a combination of (a), (b), and (c). In case of soft tissue deficiencies, these should be addressed as early as possible to increase the predictability of the surgical interventions. This article reviews the main causes for peri‐implant soft tissue complications and presents different therapeutic options for the management of various clinical scenarios.

Outcome measures and methods of assessment of soft tissue augmentation interventions in the context of dental implant therapy: A systematic review of clinical studies published in the last 10 years

AIM

To identify and report outcome measures and methods of assessment on soft tissue augmentation interventions in the context of dental implant therapy reported in clinical studies published in the last 10 years.

MATERIAL AND METHODS

The protocol of this PRISMA 2020-compliant systematic review was registered in PROSPERO (CRD42021252214). A literature search was conducted to identify articles that met the pre-established eligibility criteria. Data of interest, with an emphasis on outcome measures, were extracted. For each outcome, specific methods and timing of assessment were described in detail. Following a critical qualitative analysis of the data, outcome measures were categorized. Primary outcomes were identified and frequency of reporting in the selected articles was calculated. Additionally, risk of bias assessments were performed for individual articles and primary outcomes.

RESULTS

Ninety-two articles, of which 39 reported randomized controlled trials (RCTs), 20 reported non-RCTs, and 33 reported case series studies, were selected. Outcome measures were categorized into either investigator-evaluated outcome measures (i.e., clinical, digital imaging, esthetic, histologic, biomarker, and safety) or patient-reported outcome measures (PROMs). Clinical outcomes were the most frequently reported type of outcome. Considering all categories, the most frequently reported primary outcomes were facial mucosa thickness assessed with clinical methods (22.83%), facial keratinized mucosa width assessed with clinical methods (19.57%), facial mucosal margin position / recession assessed with clinical methods (18.48%), facial mucosa thickness assessed with digital imaging methods (11.96%), facial soft tissue volume assessed with digital imaging methods (9.78%), and supracrestal tissue height assessed with clinical methods (9.78%). No distinguishable patterns of association between specific types or quality (level of bias) of clinical studies and the choice of primary outcomes were observed.

CONCLUSION

Clinical research on peri-implant soft tissue augmentation has progressively increased in the last 10 years. Although clinical outcome measures were the most frequently reported outcomes in the selected literature, trends in the field are indicative of a shift from traditional clinical assessment methods to the use of digital technologies. PROMs were generally underreported but should be considered an integral methodological component in future clinical studies. This article is protected by copyright. All rights reserved.

[Evaluation of the clinical effectiveness of the use of a navigational surgical template in the vestibuloplasty protocol in patients with periodontal diseases]

THE AIM OF THE STUDY

Was to evaluate the clinical effectiveness of the use of a navigational surgical template in the vestibuloplasty protocol in patients with periodontal diseases.

MATERIALS AND METHODS

There were 48 people selected to participate in the study and randomly divided into 2 equal groups. The patients of the main group underwent vestibuloplasty procedure using a free gingival graft modeled using the developed protocol and a navigational surgical template. Patients in the control group underwent a similar operation using classical technology. The study assessed postoperative pain, the index of early wound healing, Doppler fluometry of the transplanted flap and flap morphometric measurements.

RESULTS

The results of all conducted studies confirmed the effectiveness of the developed clinical protocol.

CONCLUSION

According to objective and subjective assessments, the use of a surgical navigation template can reduce the time and invasiveness of vestibuloplasty surgery, make it more comfortable for the patient and get a more predictable clinical result.

Patient-reported outcome measures following soft-tissue grafting at implant sites: A systematic review

OBJECTIVES

To review the available literature on patient-reported outcome measures (PROMs) following soft tissue augmentation at implant sites.

MATERIALS AND METHODS

A comprehensive electronic and manual search was performed to identify clinical studies that involved soft tissue augmentation around dental implants and reported PROMs, including post-operative morbidity, painkillers intake, quality of life, aesthetics and satisfactions.

RESULTS

Nineteen articles were included in the qualitative analysis. Autogenous grafts (free gingival graft and connective tissue graft), acellular dermal matrix and xenogeneic collagen matrix were utilized, either with a bilaminar- or an apically positioned flap approach. PROMs reported in the literature included perceived hardship of the procedure and pain during the surgery, post-operative morbidity, painkillers intake, number of days with discomfort, satisfaction, aesthetic evaluation, quality of life and willingness to undergo the treatment again. Most of the included studies showed similar PROMs between autogenous grafts and substitutes, in terms of post-operative morbidity, painkillers intake, quality of life, aesthetic assessment and satisfaction. Nevertheless, a trend towards lower post-operative discomfort was observed for graft substitutes. High scores for patient satisfaction and aesthetic evaluation were observed in all the interventions compared to non-grafted sites.

CONCLUSIONS

PROMs represent a crucial endpoint of clinical studies evaluating the outcomes of soft tissue grafts at implant sites. Most of the studies did not find significant differences in terms of patient morbidity and painkillers between autogenous grafts and substitutes. Soft tissue grafting can enhance patient satisfaction and aesthetic evaluation compared to non-grafted sites.

Design of customized soft-tissue substitutes for posterior single-tooth defects: A proof-of-concept in-vitro study

OBJECTIVES

Soft-tissue volume augmentation treatments do not provide the satisfactory long-term functional and esthetic outcomes. The aim of the study was to develop a standardized digital procedure to design individual soft-tissue substitutes (STS) and apply mathematical modeling to obtain average shape STS for single posterior tooth defects.

MATERIAL AND METHODS

Thirty-three casts from 30 patients were scanned. STS were designed with a computer-aided design software and a systematic procedure standardized the measurements across all STS using 3D-analysis software. The occlusal, mesial-distal, and buccal-lingual planes were defined to partition, each STS and produce a mesh. The thickness values of each 3D slice were documented in a coordinate system chart to generate a scatter graph. Graphs were embedded into images (Orange software) and images were analyzed via hierarchical clustering.

RESULTS

Three STS groups were identified according to shape. Two shapes corresponded to the maxilla defects: a square (n = 13) with dimensions of 10 mm in a lingual-buccal (length) and 7-10 mm in a mesial-distal (width) direction; a rectangle (n = 11) of 11 mm in length and 4-7 mm in width. The average shape for mandible defects (n = 9) was smaller (6-8 mm in length, 5-10 mm in width). The highest thickness in all STS was in the buccal portion, above the alveolar ridge, with median values of 2 mm. The lowest thickness of 0.2 mm was at the edges.

CONCLUSIONS

The study developed novel methodology to design customized, as well as average shape STS for volume augmentation. Future STS harboring adapted geometry might increase volume augmentation efficiency and accuracy, while reducing surgical time.

Clinical evaluation of xenogeneic collagen matrix versus free gingival grafts for keratinized mucosa augmentation around dental implants: A randomized controlled clinical trial

AIM

To evaluate the outcomes of an apically repositioned flap (ARF) plus xenogeneic collagen matrix (XCM) in augmenting keratinized mucosa width (KMW) around dental implants when compared with ARF plus free gingival grafts (FGG).

MATERIALS AND METHODS

Twenty-six participants with at least one site with KMW ≤2 mm were randomized into FGG or XCM group. Clinical examinations were performed at baseline and at 2 and 6 months after surgery, including KMW, keratinized mucosa thickness, gingival index (GI), and probing depth (PD). Post-operative pain and patient satisfaction were also evaluated.

RESULTS

At 6 months, FGG attained a greater increase of KMW and thicker mucosa than XCM (4.1 ± 1.6 mm vs. 1.8 ± 1.0 mm, p < .001; 1.7 ± 0.6 mm vs. 1.2 ± 0.3 mm, p < .01). Regarding GI, PD, post-operative pain, aesthetic outcomes, and patient satisfaction, no significant difference could be detected. Moreover, the operation time of XCM group was shorter (60 ± 9 min vs. 39 ± 8 min, p < .001).

CONCLUSIONS

FGG could result in greater increase of KMW than XCM, though both could increase KMW, maintain peri-implant health, and attain comparable aesthetic outcomes. The use of XCM was associated with reduced operation time.

Outcomes of alveolar segmental 'sandwich' osteotomy with interpositional particulate allograft for severe vertical defects in the anterior maxilla and mandible

The purpose of this study was to report the outcomes of interpositional osteotomy with mineralized allograft in the treatment of alveolar vertical defects in preparation for implant placement. Thirteen defects (11 maxillary and two mandibular) were treated with osteotomy segments ranging in length from two to five missing teeth. The segments were positioned 5-7 mm coronally, with the gap space filled with allograft and then fixated with titanium hardware. Vertical bone augmentation was analyzed by superimposing pre- and post-surgical cone beam computed tomography images and stratified based on the length and number of missing teeth in each edentulous segment. The mean vertical bone gain was 3.7 ± 1.6 mm in the area of greatest vertical defect and the mean length of the transport segment was 20.5 ± 8.1 mm. These segments represented two-, three-, four-, or five-tooth edentulous sites; the mean vertical bone gain for these segments was 1.7 ± 0.5 mm, 3.8 ± 1.0 mm, 4.6 ± 0.9 mm, and 6.7 ± 0.0 mm, respectively. Stability of vertical height gain was found to be directly proportional to the span length of the osteotomy segment, with the largest five-tooth segment achieving the greatest gain. Vertical bone gain in two-tooth segments was minimal, indicating a moderate amount of resorption.

Clinical evaluations of free gingival grafting before implant placement to increase keratinized tissue width in molar regions: A retrospective case series

OBJECTIVES

To evaluate the dimensional changes of the keratinized tissue width (KTW) in molar regions after augmentation by free gingival grafts (FGG) before implant placement.

MATERIAL AND METHODS

In seventeen patients, twenty implant sites in molar regions with KTW ≤3 mm at the buccal aspect received FGG 2 months before implant placement. KTW at the buccal aspect was measured before FGG (T0), immediately before implant placement (T1), at the time of impression taking for final prosthesis fabrication (T2), and at the end of the follow-up period after loading (T3, 12-48 months). Changes in KTW before and after FGG, as well as the alterations during the follow-up period after loading, were analyzed. Shapiro-Wilk test, paired Student's t test, and Wilcoxon signed-rank test were used for the data analysis at α = 0.05.

RESULTS

KTW at the buccal aspect of the alveolar ridge was observed with a significant gain of 5.9 ± 1.3 mm at T1 (p < .001). The shrinkage of KTW from T2 to T3 was 8.5%, which was limited but statistically significant (p = .008). KTW at the buccal aspect of implant restorations was 5.0 ± 1.5 mm at T3.

CONCLUSIONS

Within the limitations of the present study, our data suggest that using FGG to increase KTW in molar regions before implant placement had a predictable result. The buccal KTW had a limited reduction and was ≥3 mm with more than 12 months of follow-up after loading.

Clinical comparison of a xenogeneic collagen matrix versus subepithelial autogenous connective tissue graft for augmentation of soft tissue around implants

Dental implant placement is a predictable therapy for replacing teeth. Nevertheless, mechanical, biological, and aesthetic complications frequently occur. The aim of this study was to compare the clinical outcomes of a xenogeneic collagen matrix (XCM) used at the time of implant placement as an alternative to a subepithelial connective tissue graft (SCTG), for soft tissue augmentation. This was a prospective clinical trial with 12 months of follow-up. In the control group, soft tissue augmentation at the time of implant placement was performed with a SCTG, while in the test group, a XCM was employed. At 12 months postoperative, all xenografts showed no postoperative complications. In both groups, a significantly greater thickness was observed on the buccal and occlusal sides from preoperative to 3 months postoperative (P<0.05). No statistically significant difference in pink aesthetic score (P=0.379, 6 months postoperative) or marginal bone loss (P=0.449 at 3 months postoperative, P=0.778 at 6 months postoperative) was observed between the groups. Statistically significant differences in pain perceived by the patients (P<0.0001) and the time to complete the surgical procedure (P=0.0008) were detected. At 12 months after surgery, XCM provided similar clinical results in terms of soft tissue augmentation on the buccal and occlusal sides as compared with the SCTG.

Volumetric soft tissue alterations in the early healing phase after peri- implant soft tissue contour augmentation with a porcine collagen matrix versus the autologous connective tissue graft: A controlled clinical trial

AIM

This study evaluates the early volumetric changes after buccal soft tissue contour augmentation around implants with a porcine collagen matrix (CM) vs. the subepithelial connective tissue graft (SCTG) from the palate.

MATERIALS AND METHODS

14 patients were enrolled after early implant placement with simultaneous contour augmentation and persistent buccal tissue deficits. At implant exposure, buccal soft tissues were thickened with the CM (n = 7) or the SCTG (n = 7). Impressions were taken before and after surgery, after ten days, one, three and six months. Impressions were digitized and augmented regions 3D evaluated (soft tissue volume (mm³ , %)/thickness (mm)).

RESULTS

Volume increase (mm³ ) after 6 months was 19.56 ± 8.95 mm³ (CM) and 61.75 ± 52.69 mm³ (SCTG) (insignificant, p = .058). In percentage, this was a volume loss of the initially augmented soft tissue volume (100%) of 81.76% in the CM group and 56.39% in the SCTG group (6 months). The mean soft tissue thickness increase (mm) in the buccal contour after 6 months was 0.30 ± 0.16 mm (CM) and 0.80 ± 0.61 mm (SCTG) (insignificant, p = .071).

CONCLUSION

The early healing phase is associated with a significant volume loss of the soft tissues. The SCTG shows insignificant superiority compared to the CM.

Peri-implant soft tissue phenotype modification and its impact on peri-implant health: A systematic review and network meta-analysis

BACKGROUND

The peri-implant soft tissue phenotype (PSP) encompasses the keratinized mucosa width (KMW), mucosal thickness (MT), and supracrestal tissue height (STH). Numerous approaches to augment soft tissue volume around endosseous dental implants have been investigated. To what extent PSP modification is beneficial for peri-implant health has been subject of debate in the field of implant dentistry. The aim of this systematic review was to analyze the evidence regarding the efficacy of soft tissue augmentation procedures aimed at modifying the PSP and their impact on peri-implant health.

METHODS

A comprehensive search was performed to identify clinical studies that involved soft tissue augmentation around dental implants and reported findings on KMW, MT, and/or STH changes. The effect of the intervention on peri-implant health was also assessed. Selected articles were classified based on the general type of surgical approach to increase PSP, either bilaminar or an apically positioned flap (APF) technique. A network meta-analysis including only randomized-controlled trials (RCTs) reporting on PSP outcomes was conducted to assess and compare different techniques.

RESULTS

A total of 52 articles were included in the qualitative analysis, and 23 RCTs were included as part of the network meta-analysis. Sixteen RCTs reported the outcomes of PSP modification therapy with bilaminar techniques, whereas 7 involved the use of APF. The analysis showed that bilaminar techniques in combination with soft tissue grafts (connective tissue graft [CTG], collagen matrix [CM], and acellular dermal matrix [ADM]) resulted in a significant increase in MT compared to non-augmented sites. In particular, CTG and ADM were associated with higher MT gain as compared to CM and non-augmented sites. However, no significant differences in KMW were observed across different bilaminar techniques. PSP modification via a bilaminar approach utilizing either CTG or CM showed beneficial effects on marginal bone level stability. APF-based approaches in combination with free gingival graft (FGG), CTG, CM, or ADM showed a significant KMW gain compared to non-augmented sites. However, compared to APF alone, only FGG exhibited a significantly higher KMW gain. APF with any evaluated soft tissue graft was associated with with reduction of probing depth, soft tissue dehiscence and plaque index compared to non-augmented sites compared to non-augmented sites. The evidence regarding the effect of PSP modification via APF-based approaches on peri-implant marginal bone loss or preservation is inconclusive.

CONCLUSIONS

Bilaminar approach involving CTG or ADM obtained the highest amount of MT gain, whereas APF in combination with FGG was the most effective technique for increasing KMW. KMW augmentation via APF was associated with a significant reduction in probing depth, soft tissue dehiscence and plaque index, regardless of the soft tissue grafting material employed, whereas bilaminar techniques with CTG or CM showed beneficial effects on marginal bone level stability.

Pinwheel Pedicle Flap Technique for Increasing Keratinized Tissue at Stage 2 Implant Surgery

INTRODUCTION

The goal of stage 2 implant surgery is to uncover implants while maintaining or augmenting the peri-implant keratinized tissue. Although the absolute requirement for keratinized tissue around natural teeth can be debated, implants appear to have consistently improved postoperative clinical parameters and health when there is an adequate keratinized peri-implant tissue.

CASE PRESENTATION

This article presents a new technique to optimize the keratinized tissue around implants during stage 2 surgery. Although there are many treatment options that can be considered at the time of surgery, the technique presented here has the advantage of increasing the keratinized tissue circumferentially around the implant without using a second donor site. The technique, called the "pinwheel," is presented in two cases with the same clinical presentation. Two mandibular overdenture patients with ≤3 mm of keratinized tissue over implant sites, stage 2 surgery was performed using the "pinwheel technique" to increase the keratinized tissue on the facial and lingual surfaces.

CONCLUSION

The use of the pinwheel technique to augment keratinized tissue around implants is effective and is a viable treatment option during stage 2 implant surgery.

Gingiva thickening with a porcine collagen matrix in a preclinical dog model: Histological outcomes

AIM

To compare 10-month histological and immunohistological outcomes after soft tissue thickening around teeth with a porcine collagen matrix (CM) versus a subepithelial connective tissue graft (SCTG).

MATERIAL AND METHODS

In eight beagle dogs, soft tissue thickening of the buccal gingiva of upper canines was performed with the SCTG or the CM. Connective tissue thickness (CTT) was histomorphometrically measured in the augmented regions. The augmented connective tissues were also histologically characterized and the collagen I and vascular endothelial growth factor (VEGF) expressions immunohistologically quantified.

RESULTS

CTT significantly differed between groups (SCTG: 1.32 mm ± 0.44 mm; CM: 1.06 mm ± 0.27 mm; p = .008). Descriptive histological analyses revealed mature connective tissue that did not differ between groups. Immunohistological quantification of collagen I and VEGF expressions in the connective tissue also revealed no significant inter-group differences (collagen I: SCTG, 32.64% ± 7.09% vs. CM, 30.57% ± 7.83%; VEGF: SCTG, 39.06% ± 7.27% vs. CM, 37.15% ± 9.80%).

CONCLUSION

SCTG is superior to CM with regard to CTT in this experimental model. The CM and the SCTG lead to comparable connective tissue quality ten months after connective tissue thickening.

Interim tissue changes following connective tissue grafting and two-stage implant placement. A randomized clinical trial

AIM

To determine tissue changes at implants placed either conventionally or in combination with a connective tissue graft (CTG).

MATERIALS AND METHODS

Forty-eight partially edentulous subjects were randomized into two treatment Groups, and 46 completed the study. Group-A (N_A   = 23) received crestal implant placement. In Group-B (N_B   = 23), a CTG harvested from the palate was stabilized over the implant neck. At the time of implant placement (T0), Groups were categorized as having thin mucosa ≤ 2.5 mm at the surgical site (N_{S ubgroup- AI}   = 12, N_{S ubgroup- BI}   = 11) or thick mucosa > 2.5 mm (N_{S ubgroup- AII}   = 11, N_{S ubgroup- BII}   = 12). Mucosa thickness, width of keratinized tissue (WKT), crestal bone levels and relative bone thickness were determined at T0 and at the two-stage surgery (T1).

RESULTS

At T1, on the alveolar crest, mucosa thickness significantly decreased in the thick mucosa Subgroups (-AII/-BII, both p = 0.001), but increased at thin mucosa grafted sites (p = 0.049). No significant changes were noted in the WKT for either group. Thin mucosa grafted Subgroups (-AI/-BI) demonstrated significant decreases in crestal bone levels (both p ≤ 0.008). Crestal relative bone thickness decreased in all Subgroups (p ≤ 0.027 for significant changes).

CONCLUSIONS

Connective tissue grafting resulted in smaller reductions of mucosa thickness on the alveolar crest and appeared to have the greater effects at sites with initially thin mucosa.

A retrospective study of an alternative technique for implant repositioning in the maxillary esthetic region

BACKGROUND

Implant-bone block segment repositioning may be an option of treatment for patients with vertical alveolar bone atrophy.

PURPOSE

To assess implant-bone block movement, gingival outcome and the subjective appreciation of patients after an alternative treatment of an implant-bone block segment repositioning in the maxillary esthetic region.

MATERIALS AND METHODS

Patients who underwent implant-bone block segment relocation in areas of vertical alveolar bone atrophy in the anterior esthetic region were assessed. The outcome measures were implant failure, complications after initial loading, vertical bone augmentation, papilla index, width of the keratinized mucosa, and patient satisfaction.

RESULTS

Twenty-five implants in nine consecutive patients were included in this study. During the follow-up period, only one implant failed. Vertical bone augmentation ranged from 3.0 to 8.4 mm (mean 4.9 mm). A significant improvement (P < .001) in the papilla index was observed, improving the esthetic outcome. Six patients (66.6%) had more than 2 mm of keratinized mucosa and all of the patients were satisfied with the treatment.

CONCLUSIONS

The esthetics and functional gingival outcome of oral rehabilitation in areas with vertical alveolar bone atrophy can be successfully improved with the presented technique, which had a high overall implant survival rate within a short period.

Cell therapy induced regeneration of severely atrophied mandibular bone in a clinical trial

Background

Autologous grafting, despite some disadvantages, is still considered the gold standard for reconstruction of maxillofacial bone defects. The aim of this study was to evaluate bone regeneration using bone marrow-derived mesenchymal stromal cells (MSCs) in a clinical trial, a less invasive approach than autologous bone grafting. This comprehensive clinical trial included subjects with severe mandibular ridge resorption.

Methods

The study included 11 subjects aged 52–79 years with severe mandibular ridge resorption. Bone marrow cells were aspirated from the posterior iliac crest and plastic adherent cells were expanded in culture medium containing human platelet lysate. The MSCs and biphasic calcium phosphate granules as scaffolds were inserted subperiosteally onto the resorbed alveolar ridge. After 4–6 months of healing, new bone formation was assessed clinically and radiographically, as were safety and feasibility. Bone at the implant site was biopsied for micro-computed topography and histological analyses and dental implants were placed in the newly regenerated bone. Functional outcomes and patient satisfaction were assessed after 12 months.

Results

The bone marrow cells, expanded in vitro and inserted into the defect together with biphasic calcium phosphate granules, induced significant new bone formation. The regenerated bone volume was adequate for dental implant installation. Healing was uneventful, without adverse events. The patients were satisfied with the esthetic and functional outcomes. No side effects were observed.

Conclusions

The results of this comprehensive clinical trial in human subjects confirm that MSCs can successfully induce significant formation of new bone, with no untoward sequelae. Hence, this novel augmentation procedure warrants further investigation and may form the basis of a valid treatment protocol, challenging the current gold standard.

Trial registration

EudraCT, 2012-003139-50. Registered on 21 August 2013. ClinicalTrials.gov, NCT 02751125. Registered on 26 April 2016.

Use of a surgical template for minimally invasive second-stage surgery: A dental technique

The introduction of new techniques and new technology has been directly related to successful outcomes in implant dentistry. Merging information from high-quality cone beam computed tomography images and detailed prosthetically driven digital planning translates into computer-guided surgery. A surgical template is a guide used to assist in the proper surgical placement and angulation of dental implants. However, a surgical guide not only facilitates implant placement but can also be used for other purposes, including diagnosis, treatment planning, and even second-stage surgery. In situations where multiple implants have been placed through computer-guided implant surgery, the preexisting surgical template can be used to perform the second-stage surgery with a flapless approach if the patient's soft tissue condition permits.

The Use of a Novel Porcine Derived Acellular Dermal Matrix (Mucoderm) in Peri-Implant Soft Tissue Augmentation: Preliminary Results of a Prospective Pilot Cohort Study

Objective

Over the years, several techniques have been proposed for soft tissue augmentation around dental implants in order to improve keratinized mucosa width (KMW). Recently, a porcine derived acellular dermal matrix (Mucoderm®) has been proposed as autogenous graft substitute in order to avoid palatal harvesting and obtain comparable results to connective tissue grafts, in terms of aesthetics and function. The aim of this study is to present the one-year follow-up results of this matrix in peri-implant soft tissue augmentation procedures.

Material and Methods

Twelve patients were enrolled in this pilot prospective study: a dental implant was placed in the upper premolar area and, at implant uncovering after eight weeks, the matrix was inserted. KMW gain was considered as primary outcome variable.

Results

After one month from matrix insertion, mean KMW was 7.86±3.22 mm (100%), with no statistically significant intragroup variations (p>0.05). No membrane exposures or wound healing complications occurred during postoperative phase and, after one year, mean KMW was 5.67±2.12 mm (72.13%).

Conclusions

The results of the present pilot study indicate that by placing a Mucoderm membrane during implant surgery the keratinized tissue width can be augmented, and the width remains stable for the assessment period of 12 months. Further studies with greater power and longer investigation period are needed to confirm the suggestion for clinical use. Clinical trial registration number is EudraCT number 2018-000147-16.

L-PRF for increasing the width of keratinized mucosa around implants: A split-mouth, randomized, controlled pilot clinical trial

BACKGROUND

This study aims to evaluate the use of the leukocyte- and platelet-rich fibrin (L-PRF) membranes in increasing the width of the keratinized mucosa (KM) around implants.

MATERIAL AND METHODS

Eight patients in need for bilateral widening of the KM around implants in the lower jaw were recruited for a spit-mouth randomized controlled trial. At the control site, a free gingival graft (FGG) was used, whereas at the other side (test), L-PRF membranes were applied. The primary outcome was the increase in width of KM around the implants. As secondary outcomes, the postoperative pain and surgical time were assessed. The follow-up period was 6 weeks.

RESULTS

A significant increase in the total bucco-lingual width of KM in both groups was observed, with 1.3 mm ± 0.9 extra gain (P < .05) for the FGG sites. Shrinkage of the widened areas in this period was 32.1% at the test site and 23.6% at the control site. All values of the postoperative pain scores at the control site were higher than at the test site. The mean surgery time in the test and control group was 29.1 ± 4.8 and 48.1 ± 7.7 minutes, respectively.

CONCLUSION

Within the limitations of this randomized controlled trial with split mouth design, it can be concluded that L-PRF can increase the width of KM around implants. Furthermore, the use of L-PRF results in a lower surgical time with less postoperative discomfort and pain for the patients in comparison to the FGG.

Impact of timing on soft tissue augmentation during implant treatment: A systematic review and meta-analysis

BACKGROUND

To achieve a predictable esthetic and functional outcome, soft tissue augmentation has become popular in implant treatment.

OBJECTIVES

The aim of this systematic review and meta-analysis was to assess the influence of different timing for soft tissue augmentation during implant treatment on soft tissue conditions and its stability.

MATERIAL AND METHODS

Electronic and manual searches for articles written in English up to September 2017 were performed by two independent reviewers. Human clinical studies with the purpose of evaluating outcomes (at least 3-month follow-up) of autogenous soft tissue graft for augmentation during implant treatment, either simultaneous or after implant placement (staged), were included. Cumulative changes of keratinized tissue width (KTW), soft tissue thickness (STT), and mid-buccal mucosal recession (MR) data were analyzed with a random-effects model to compare the postoperative outcomes.

RESULTS

Twenty-nine human studies (eight randomized clinical trials, six cohort studies, and 15 case series) that met the inclusion criteria were included. For the overall data, the weighted mean STT gain (1 year after surgery) was 1.03 mm (95% CI: 0.78-1.29 mm), among which the simultaneous group was 1.12 mm (95% CI: 0.75-1.49 mm) and staged group (3-6 months after implant placement) was 0.95 mm (95% CI: 0.58-1.31 mm). There was no statistically significant difference in KTW and MR between 3 months and more than 3 months after surgery.

CONCLUSIONS

This review revealed that the stability of soft tissue, in terms of KTW and mid-buccal MR, can be obtained 3 months after surgery. There is no difference between simultaneous and staged soft tissue augmentation during implant treatment, and both procedures significantly enhance KTW and STT.

Non-interventional 1-year follow-up study of peri-implant soft tissues following previous soft tissue augmentation and crown insertion in single-tooth gaps

AIM

To assess peri-implant soft tissue dimensions at implant sites, previously augmented with a collagen matrix (VCMX) or an autogenous subepithelial connective tissue graft (SCTG), between crown insertion and 1 year.

METHODS

Twenty patients with single-tooth implants received soft tissue augmentation prior to abutment connection randomly using VCMX or SCTG. Following abutment connection 3 months later, final reconstructions were fabricated and inserted (baseline). Patients were recalled at 6 months (6M) and at 1 year (FU-1). Measurements included clinical data, soft tissue thickness, volumetric outcomes and patient-reported outcome measures (PROMs).

RESULTS

The buccal soft tissue thickness showed a median decrease of -0.5 mm (-1.0;0.3) (VCMX) and 0.0 mm (-0.5;1.0) (SCTG) (p = .243) up to FU-1. The soft tissue volume demonstrated a median decrease between BL and FU-1 of -0.1 mm (-0.2;0.0) (p = .301) for VCMX and a significant decrease of -0.2 mm (-0.4; -0.1) (p = .002) for SCTG, respectively. Intergroup comparisons did not reveal any significant differences between the groups for peri-implant soft tissue dimensions and changes up to FU-1 (p > .05). PROMs did not show any significant changes over time nor differences between the groups.

CONCLUSION

Between crown insertion and 1 year, the buccal peri-implant soft tissue dimensions remained stable without relevant differences between sites that had previously been grafted with VCMX or SCTG.

Basic Principles of Bioengineering and Regeneration

In a quest to provide best-quality treatment, results, and long-term prognosis, physicians must be well versed in emerging sciences and discoveries to more favorably provide suitable options to patients. Bioengineering and regeneration have rapidly developed, and with them, the options afforded to surgeons are ever-expanding. Grafting techniques can be modified according to evolving knowledge. The basic principles of bioengineering are discussed in this article to provide a solid foundation for favorable treatment and a comprehensive understanding of the reasons why each particular treatment available can be the most adequate for each particular case.

Advanced Implant-Prosthetic Rehabilitation: How to Obtain a Correct Restoration of Both Functions and Aesthetics in Patients with Complex Combined Dental and Maxillofacial Trauma: A Case Report and Topical Review of the Literature

Aim. This study aims to explain the main steps that characterize the implant-prosthetic rehabilitation in complex combined dental and maxillofacial trauma. Material and Methods. A 20-year-old patient reported an extensive facial trauma which also involved the alveolar process of the maxillary bone. The patient reported a maxillofacial fracture and the loss of teeth 1.3, 1.2, 1.1, and 2.1. A "Le Fort" type 2 fracture was also reported, with the malar bone involvement. After reduction and containment of bone fractures, through appropriate mounting plates, appropriate functional and aesthetic rehabilitation of the patient were replaced thanks to a temporary removable prosthesis. After 6 months, the patient performed numerous clinical investigations, aimed at a proper planning of implant-prosthetic rehabilitation of the upper dental arch. Conclusion. With the planning of the case, as well as respecting the surrounding biological structures, the surgery of implants can be carried out with the most appropriate procedure. Lastly, new dental implants with highly bioactive surfaces have been developed, providing an excellent and rapid bone integration.