Effect of peri-implant mucosal thickness on esthetic outcomes and the efficacy of soft tissue augmentation procedures: Consensus report of group 2 of the SEPA/DGI/OF workshop

Comparison of the Histological Structure of an Anterior as well as a Posterior Biopsy From the Human Palate: A Comparative Study

AIM

To compare the histological structure of biopsies from the anterior and posterior regions of the human palate in order to gain insights into potential differences of soft tissue harvesting sites.

METHODS

This comparative study involved 20 participants, from each of whom four samples from the palatal mucosa were collected. The biopsies were histologically processed and subsequently analysed. The thickness of the epithelium, lamina propria, and the length of the rete pegs were measured using a microscope. In addition, parameters such as collagen fibres, elastic fibres, elastic connective tissue, loose connective tissue and the background were measured.

RESULTS

The mean epithelial thickness was 0.42 mm anteriorly and 0.37 mm posteriorly. The mean thickness of the lamina propria was 0.81 mm anteriorly and 0.85 mm posteriorly. Within the region of interest, collagen fibres were significantly less abundant anteriorly than posteriorly (p = 0.016). The loose connective tissue showed a significantly higher occurrence in the anterior compared with the posterior sampling site (p = 0.004).

CONCLUSION

This trial indicates no differences in terms of the thickness of the lamina propria. There was a higher concentration of collagen fibres and a lower concentration of loose connective tissue in the posterior region of the palate.

Soft-tissue volume augmentation during early, delayed, and late dental implant therapy: A systematic review and meta-analysis on professionally determined esthetics and self-reported patient satisfaction on esthetics

The objective of the study was to assess the effect of soft-tissue volume augmentation during early, delayed, and late dental implant therapy in terms of professionally determined esthetics and self-reported patient satisfaction on esthetics. For this, a comprehensive electronic literature search was performed to identify randomized clinical trials (RCTs) and controlled clinical trials (CCTs) reporting professionally determined esthetic outcomes and self-reported patient satisfaction on esthetics (primary outcomes) during early, delayed, and late dental implant placement comparing soft-tissue volume augmentation to the absence of soft-tissue grafting (control) (PICO 1) or comparing various soft-tissue augmentation techniques, procedures, and materials (PICO 2). Secondary outcomes were mucosal thickness (MT), intra- and postoperative complications, marginal soft-tissue-level changes, keratinized tissue width, radiographic marginal bone levels, and clinical parameters for the diagnosis of peri-implant tissue health. The standard mean differences (SMD)/weighted mean differences (WMD) were estimated for the Pink Esthetic Score (PES), self-reported patient satisfaction assessed by Visual Analog Scale (VAS) and MT gain for PICO 1 and PICO 2 by employing a random effect model. Five RCTs were included for PICO 1, whereas 7 RCTs and 1 CCT addressed PICO 2. PICO 1: The SMD for the PES between autogenous soft-tissue grafting (SCTG) and the absence of grafting (control group) was 0.47; 95% CI [-0.15, 1.09; p = 0.14] based on 5 RCTs. The SMD for the VAS values for patient-reported satisfaction on esthetics in the SCTG and control group was 0.46; 95% CI [-0.12, 1.03; p = 0.12] (2 RCTs). The WMD for gain of MT amounted to 1.06 mm; 95% CI [0.81, 1.31; p = 0.00] in favor of the SCTG group (3 RCTs). PICO 2: The SMD for the PES comparing collagen-based matrices (CM group) to the SCTG group was -0.32; 95% CI: (-0.57, -0.07; p = 0.01), in favor of the SCTG group (5 RCTs and 1 CCT). The SMD for the VAS for patient-reported satisfaction on soft-tissue esthetics was 0.24; 95% CI: (-0.31, 0.78; p = 0.40) (2 RCTs comparing CM vs. SCTG). The WMD for gain of MT was -0.27 mm; 95% CI: (-0.36, -0.17; p = 0.00), significantly favoring the SCTG group (4 RCTs). Professionally and patient-assessed outcomes showed no substantial differences between autogenous soft-tissue grafting and the absence of grafting for early, delayed, and late implant placement. However, autogenous soft-tissue grafts led to significantly improved esthetic outcomes as assessed by professionals compared to soft-tissue substitutes. Patient-assessed outcomes, nevertheless, were similar regardless of the grafting material (i.e., SCTG or soft-tissue substitute). Therefore, autogenous soft-tissue grafting, though, resulted in a considerably higher gain in mucosal thickness compared to both the absence of soft-tissue grafting and the use of soft-tissue substitutes. Complications and adverse events were rarely reported by the included studies, thus suggesting that many trials underreport harms (e.g., complications).

3D-Analysis of Peri-Implant Soft Tissue Gain With Collagen Matrix and Connective Tissue Graft: A Randomized Control Trial

OBJECTIVES

To compare the efficacy of the connective tissue graft (SCTG) and the collagen matrix (VXCM) in terms of soft tissue gain at the buccal site around a single implant.

METHODS

The study was designed as a randomized, controlled clinical trial. This trial was registered in ClinicalTrial.gov with the identifier NCT05870774 and is accessible under the following link: https://clinicaltrials.gov/study/NCT05870774?term=NCT05870774&rank=1. This clinical trial was not registered prior to participant recruitment and randomization. Patients with a single tooth gap and horizontal soft tissue thickness deficiency were enrolled in the study. Sites were randomly allocated to the control (SCTG) or test group (VXCM: Geistlich Fibro-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) to augment buccal soft tissue thickness. The primary outcome was soft tissue gain 3 months post-op. Secondary outcomes included soft tissue gain 6 months post-op, the pink aesthetic score (PES), and patient-reported outcome measures (PROMs).

RESULTS

Patients' recruitment started on 28 October 2021 and ended on 25 December 2022. Thirty-two patients were enrolled and subjected to intervention. Sixteen patients were included per group. Three months post-op, soft tissue gain at the buccal site was 1.77 ± 0.61 mm in the VXCM group and 1.26 ± 0.41 mm in the SCTG group (p = 0.0003). Six months post-op, soft tissue gain was 1.11 ± 0.44 mm in the VXCM group and 1.43 ± 0.81 mm in the SCTG group (p = 0.0459). PROMs, including pain perception, favored the VXCM group. SCTG demonstrated favored results in PES.

CONCLUSION

SCTG remains the gold standard for increasing soft tissue thickness in terms of the clinical result.

Identifying Key Factors in Papilla Growth Around Implants: Focus on Intraoral Negative Pressure

The absence of interdental papillae in dental prosthetics often leads to unsatisfactory esthetic outcomes, such as black triangles and elongated clinical crowns. While previous research has demonstrated that papillae can regenerate in a coronal direction, the underlying mechanisms remain incompletely understood. Several theories have been proposed to explain this phenomenon, but no clear cause-effect relationship has been established among the various factors involved in spontaneous papilla growth around implants. This study aims to identify and classify the factors influencing this process. Various potential contributors were analyzed, including adjacent elements, buccal-lingual papilla width, contact point position, convergent neck design, crown overcontour, intraoral negative pressure, and others. To systematically organize these factors, a modified Overton Window and a mind map were employed. The factors were categorized as cause-related, essential, or influencing based on the collective opinion of the research group following a comprehensive review of the relevant literature. In the absence of clear evidence supporting a definitive cause-effect relationship, Occam's Razor (the principle of parsimony) was applied to identify the most plausible cause-related factors.

Soft tissue elasticity at teeth and implant sites. A novel outcome measure of the soft tissue phenotype

AIM

To assess ultrasonographic tissue elasticity at teeth and implant sites and its variation after peri-implant soft tissue augmentation with a connective tissue graft (CTG).

METHODS

Twenty-eight patients, each contributing with one clinically healthy dental implant exhibiting a soft tissue dehiscence (PSTD), were included. Implant sites were augmented with CTG and monitored over 12 months. Ultrasonographic strain elastography, expressed as strain ratios (SR1, SR2, and SR3, respectively) was assessed at baseline, 6-, and 12-month, and compared with the corresponding contralateral homologous natural tooth. SR1 assessed the strain/elasticity of the midfacial coronal portion of the soft tissue in comparison to the natural tooth crown/implant-supported crown, SR2 evaluated the strain of the midfacial coronal soft tissue in relation to the one of the alveolar mucosa, while SR3 depicted the strain of the midfacial soft tissue in relation to the interproximal soft tissue on the transverse ultrasound scan.

RESULTS

SR1 in natural dentition and at implant sites was 0.20 ± 0.08 and 0.30 ± 0.14, respectively (p = .002), indicating that the coronal portion of the soft tissue around teeth is generally more elastic than its counterpart around dental implants. Soft tissue augmentation with CTG promoted an increased stiffness of the midfacial coronal portion of the soft tissue over 12 months (p < .001 for SR1, SR2, and SR3). Strain ratios at the 12-month time points were significantly higher than the values observed at 6 months (p < .001). Regression analysis demonstrated that strain elastography ratios in natural dentition were significantly associated with keratinized gingiva width, and gingival thickness. At implant sites, SR1 was significantly associated with keratinized mucosa width and mucosal thickness (p < .001 for both correlations), SR2 was significantly associated with keratinized mucosa width (p = .013), and SR3 was significantly associated with the surgical technique performed in combination with CTG (p = .022).

CONCLUSION

Ultrasound strain elastography captures and quantifies tissue elasticity and its changes after soft tissue augmentation. A different baseline tissue elasticity was observed between teeth and dental implants in the most coronal aspect of the soft tissue. The main factors affecting tissue elasticity-related outcomes were the keratinized tissue width, and mucosal thickness.

Prosthetic Soft Tissue Management in Esthetic Implant Restorations, Part I: Presurgical Planning, Implant Placement, and Restoration Timing. A Narrative Review

OBJECTIVES

This two-part review article delineates various techniques to enhance esthetic outcomes in anterior implant treatments. Part I concentrates on presurgical measures, case selection, implant placement, and restoration timing. Part II discusses post-surgical steps, the temporary restoration phase, the emergence profile contour, abutment types, and impression techniques.

MATERIAL AND METHODS

A comprehensive search was conducted using Medline/PubMed, Embase, Scopus, and the Cochrane Library. The primary keywords included were "Dental Implants," "Dental Prosthesis, Implant-Supported," "Esthetics, Dental," "Dental Impression Techniques," and "Tissue Management."

RESULTS

Initially, 1472 studies were identified, from which 187 were selected based on publication year and title relevance. After removing duplicates, 84 abstracts were reviewed in full text, culminating in 59 studies being thoroughly analyzed.

CONCLUSIONS

Optimal esthetics in implant restorations are attainable through meticulous treatment planning, precise surgical execution, and systematic restorative steps, ensuring predictable outcomes. Factors such as a thick gingival biotype, an intact facial bone wall, and atraumatic extraction significantly contribute to superior esthetic results. Immediate implant placement combined with immediate provisionalization provides the most predictable outcomes by supporting and maintaining soft tissue architecture. Conversely, delayed implant placement and provisionalization often require extensive manipulation of collapsed soft tissues to achieve desired esthetics.

Volumetric changes of porcine collagen matrix and free gingival grafts for soft-tissue grafting to increase the width of keratinized tissue around dental implants: a retrospective clinical study

AIM

To compare three-dimensional changes of aporcine derived collagen matrix (CM) and free gingival grafts (FGG) for increasing keratinized tissue (KT) at dental implants over a 24-month follow-up period.

MATERIALS AND METHODS

This retrospective study enrolled 25 patients exhibiting 41 implants with deficient KT width (i.e., < 2 mm) who underwent soft tissue augmentation using either CM (11 patients/15 implants) or FGG (14 patients/26 implants). The primary outcome was tissue thickness change (mm) at treated implant sites between 1- (S0), 12- (S1), and 24-months (S2). Secondary outcome was the changes of KT width over a 24-month follow-up period.

RESULTS

Dimensional analyses from S0 to S1 and from S0 to S2 revealed a mean decrease in tissue thickness of -0.05 ± 0.35 mm and - 0.31 ± 0.41 mm in the CM group, and - 0.23 ± 0.38 mm and - 0.22 ± 0.81 mm in the FGG group, with no significant differences found between the groups (S0-S1: p = 0.14, S0-S2: p = 0.58). Within S1 and S2, the CM and FGG groups displayed comparable tissue thickness reduction (CM: -0.32 ± 0.53 mm, FGG: -0.02 ± 0.21 mm; p = 0.07). The FGG group exhibited a significantly greater KT gain 24-months compared to the CM group (CM: 1.50 ± 1.14 mm, FGG: 4.04 ± 1.65 mm; p < 0.001).

CONCLUSIONS

CM and FGG were associated with comparable three-dimensional thickness changes over a period of 24 months. A significantly wider KT band could be established in the FGG group.

The Bio-Restorative Concept for Implant-Supported Restorations

OBJECTIVE

This study aims to present the bio-restorative approach in implant dentistry, which combines biological and restorative concepts through digital planning. This concept combines periodontal, surgical, and prosthetic variables, aiming to reduce patient morbidity while achieving satisfactory esthetic and functional outcomes in implant-supported restorations in the long term.

OVERVIEW

Implant dentistry evolved from a primarily surgical to a recent prosthetically driven approach. This evolution was partly due to advancements in bone reconstructive techniques and an increased demand for esthetic outcomes. Recently, digital planning has introduced a new paradigm that allows for the full integration of both approaches. The bio-restorative concept considers functional, esthetic, and biological variables in a virtual planning environment. This is achieved through the simultaneous digital assessment of (A) anatomical site characteristics and (B) implant restorative variables. These variables include digital tooth arrangement, soft-hard tissue conditions, implant variables, supra-platform components, and a surgical plan that respects or modifies peri-implant phenotype.

CONCLUSIONS

The bio-restorative concept is intended to improve contemporary implant dentistry by integrating updated biological and prosthetic notions through digital planning. Adopting this paradigm has the potential to redefine the standards in implant dentistry, fostering a holistic and patient-centered approach.

CLINICAL CONSIDERATIONS

It enhances patient and clinician satisfaction through more efficient and less invasive procedures. Significantly, it improves predictability, leading to successful implant-supported restorations in the long term.

A Novel Prehydrated Porcine-Derived Acellular Dermal Matrix: A Histological and Clinical Evaluation

It is well known that soft tissue quality and quantity around dental implants is of paramount importance for later peri-implant health. For this purpose, the clinical and histological outcomes of the peri-implant mucosa, following soft tissue augmentation for soft tissue improvement with a novel prehydrated porcine acellular dermal matrix graft (PPADMG) in conjunction with simultaneous implant placement, were evaluated in this case series. Twenty-two patients were included in the study. They underwent a late implant placement protocol combined with PPADMG for soft tissue augmentation. A punch biopsy was taken at the time of uncovery of the submerged healed implant after a mean of 157 days healing time. Supracrestal soft tissue height (STH) was measured at the time of implant placement and uncovery. All sites showed a clinical increase in STH. The histological structure of the biopsies resembled a similar structure as found in the healthy oral mucosa. No unexpected tissue reactions could be found. Within the limits of this clinical and histological study, it may be concluded that STH improvement with this novel porcine-derived acellular dermal matrix, in combination with simultaneous implant placement, is a viable option to create a peri-implant tissue thickness and stability.

Characteristics of healthy peri-implant tissues

This article forms part of the themed issue on dental implants, with the general dentist being the main intended reader and with particular relevance to primary care dental professionals. It aims to describe the various characteristics of the implant in health, address contemporary developments in implant dentistry and offer some novel insights on the prevention of peri-implant diseases. A healthy implant exhibits specific histological, clinical and radiographic characteristics. Understanding such aspects leads to proper diagnosis and measures to maintain tissue integrity and prevent the development and progression of peri-implant diseases. Moreover, internationally and widely accepted definitions and recommendations based on expert consensus have been put forward to guide day-to-day clinical practice. This information should provide general practitioners with the means necessary to achieve the best possible outcome for their patients.

Maintenance of peri-implant health in general dental practice

The long-term maintenance or restoration of peri-implant tissues' health depends on the strategic implementation of preventive measures and interventions. These measures should be initiated before implant placement and continued throughout a patient's lifetime, as part of a tailored and comprehensive supportive peri-implant care (SPIC) programme. Central to the clinical efforts of maintaining and rehabilitating peri-implant tissues are several key factors, including the ongoing assessment and frequent monitoring of tissue health and stability, proactive oral health promotion, the control of risk factors and indicators and the provision of professional plaque biofilm removal. It is of paramount importance to underline that SPIC should not limit its scope exclusively to patients already in a state of peri-implant health; in fact, it is imperative that it should extend its protective effect to individuals who have been previously diagnosed and treated for peri-implant diseases, focusing on preventing its recurrence and progression, thereby avoiding further complications, such as implant loss.This narrative review presents an overview of the current literature on the maintenance of peri-implant tissues' health and the steps of SPIC providing insights into the critical factors to be considered when managing dental implant patients in the general dental practice.

Efficacy of alveolar ridge preservation with xenografts and resorbable socket sealing materials in the esthetic region: A systematic review with meta-analyses

AIM

The present systematic review aimed to identify and summarize the clinical, radiographic, and histological outcomes of alveolar ridge preservation using bone xenografts and absorbable sealing materials compared with spontaneous healing in the esthetic zone.

MATERIALS AND METHODS

Randomized clinical trials (RCTs) fulfilling specific eligibility criteria were included. Two review authors independently searched for eligible studies, extracted data from the published reports and performed the risk of bias assessment (RoB 2 tool). Study results were summarized using random effects meta-analyses.

RESULTS

Thirteen articles concerning 10 RCTs were included, involving a total of 357 participants. Most of studies were considered as "low" risk of bias. Meta-analyses indicated less horizontal (difference in means-MD = 1.88 mm; p < 0.001), vertical mid-buccal (MD = 1.84 mm; p < 0.001) and vertical mid-lingual (MD = 2.27 mm; p < 0.001) bone resorption in alveolar ridge preservation compared to spontaneous healing as assessed clinically. Bone changes assessed radiographically showed consistent results in terms of horizontal (at 1 mm: MD = 1.84 mm, p < 0.001), vertical mid-buccal (MD = 0.95 mm; p < 0.001) and mid-lingual (MD = 0.62 mm; p = 0.05) resorption. Part of the bone resorption in the spontaneous healing group was compensated by soft-tissues, since the observed differences between groups in linear ridge reduction evaluated through cast models superimposition were smaller (MD = 0.52 mm; p < 0.001).

CONCLUSIONS

Alveolar ridge preservation with xenogeneic bone substitutes and non-autogenous resorbable socket sealing materials is efficacious in reducing post-extraction bone and ridge changes in the esthetic region.

Post-extraction volumetric analysis of alveolar ridge contour using subepithelial connective tissue graft in esthetic zone: a randomized controlled clinical trial

OBJECTIVES

The aim of this randomized clinical trial was to assess the alveolar ridge contour after soft tissue augmentation using subepithelial connective tissue graft (SCTG) buccal to fresh extraction sockets in patients with thin buccal bone, versus minimally-traumatic extraction followed by spontaneous healing solely.

MATERIALS AND METHODS

Forty non-restorable maxillary teeth in the esthetic zone were randomly assigned into two groups: minimally-traumatic extraction with SCTG (test) and minimally-traumatic extraction followed by spontaneous healing (control). The outcomes assessed included linear volumetric change of buccal soft tissue contour, vertical tissue loss, gingival thickness (GT), and interdental papilla (IDP) height after 6 months.

RESULTS

The SCTG group showed a significant improvement (P < 0.001) in all outcomes after 6 months. The SCTG group showed a statistically significant (P < 0.001) gain in the buccal soft tissue volumetric change compared to the control group. The SCTG group showed a statistically significant increase in GT (P < 0.001) and IDP height (P < 0.05) after 6 months compared to the control group.

CONCLUSIONS

The use of SCTG buccal to extraction sockets in the anterior maxilla might be considered as a predictable approach for preserving the alveolar ridge contour.

CLINICAL RELEVANCE

SCTG buccal to extraction sockets might counteract post-extraction hard and soft tissue alterations in the esthetic zone.

Critical review on bone grafting during immediate implant placement

In the last 20 years, immediate implant placement has been proposed as a predictable protocol to replace failing teeth. The research conducted in preclinical and clinical studies have focused on soft and hard tissue changes following tooth extraction and immediate implant placement. Different approaches for hard and soft tissue grafting together with provisional restorations have been proposed to compensate tissue alterations. This review analyzed some relevant clinical and preclinical literature focusing on the impact of bone grafting procedures on immediate implant placement in terms of hard and soft tissue changes, aesthetic results, and patient-related outcomes.

Volumetric analysis on the use of customized healing abutments with or without connective tissue graft at flapless maxillary immediate implant placement: A randomized clinical trial

OBJECTIVES

To evaluate buccal volume change after using a customized healing abutment with or without connective tissue grafts (CTG) in flapless maxillary immediate implant placement (IIP).

MATERIALS AND METHODS

The present study was designed as a randomized clinical trial (RCT). Patients treated with flapless maxillary IIP were allocated into two groups, both receiving a customized healing abutment, and additionally, the test group received a CTG. A cone-beam computerized tomography (CBCT) allowed to access the initial buccal bone thickness (BT). Digital impressions were taken prior to extractions (T0), 1 month (T1), 4 months (T2), and 12 months (T3) after implant insertion and superimposed with computer software allowing to compute variables related to buccal volume variation (BVv) and total volume variation (TVv) (ClinicalTrials.gov: NCT05060055).

RESULTS

Thirty-two patients (mean age 48 ± 11 years), sixteen in each group, were evaluated after a 12-month period. After 1 year of treatment, no significant differences were found between groups, although in participants with BT ≤1 mm, control and test groups showed a BVv of -14.18 ± 3.49% and -8.30 ± 3.78%, respectively (p = .033). Regarding mucosa height variation variables, the control group showed approximately the triple vertical recession in both papillae.

CONCLUSIONS

The placement of a CTG was not capable of completely maintaining the initial peri-implant tissue architecture, although in thin-bone phenotypes, less dimensional changes are expected when a CTG was used.

Do soft tissue augmentation techniques provide stable and favorable peri-implant conditions in the medium and long term? A systematic review

OBJECTIVES

To review the available literature on the medium- and long-term effects of soft tissue augmentation (STA) at implant sites and to explore the effects of the different approaches on clinical-, patient-reported, and health-related parameters.

MATERIALS AND METHODS

A comprehensive electronic and manual search was performed to identify prospective clinical studies that assessed the medium- and long-term (≥36 months) outcomes following STA, including number of sites maintaining peri-implant health and number of sites developing peri-implant disease, incidence of complications, stability of the clinical, volumetric, and radiographic parameters, and patient-reported outcome measures (PROMs).

RESULTS

Fifteen studies were included in the qualitative analysis. STA was performed with either a bilaminar- or an apically positioned flap (APF) approach, in combination with autogenous grafts (free gingival graft [FGG] and connective tissue graft [CTG]) or substitutes (acellular dermal matrix [ADM] and xenogeneic cross-linked collagen matrix [CCM]). An overall high survival rate was observed. Most of the augmented implant sites maintained peri-implant health in the medium and long term, with the incidence of peri-implant mucositis and peri-implantitis ranging from 0% to 50% and from 0% to 7.14%, respectively. The position of the soft tissue margin following APF + FGG and bilaminar approaches involving CTG or CCM was found to be stable over time. No substantial changes were reported for plaque score/index, bleeding on probing/bleeding index, and probing depth between early time points and following visits. CTG-based STA procedures resulted in a stable or increased dimension of keratinized mucosa width (KMW) and mucosal thickness (MT)/volumetric outcomes over time, when compared with early follow-ups. Most of the included studies described stable marginal bone levels at the grafted implant sites over time. No substantial changes for patient-reported outcomes and professionally assessed esthetic results were reported at different time points.

CONCLUSIONS

Implants that received STA showed overall high survival rate and relatively low incidence of peri-implantitis in the medium and long term. Augmented sites seem to maintain the level of soft tissue margin and marginal bone over time, while non-augmented implants may exhibit apical shift of the soft tissue margin. The overall favorable early outcomes obtained with STA are maintained in the medium and long term, with an increase in KMW and MT that may be expected over time at CTG-augmented sites.

Clinical efficacy of soft-tissue augmentation on tissue preservation at immediate implant sites: A randomized controlled trial

AIM

This randomized controlled trial aimed to investigate the efficacy of soft-tissue augmentation (STA) with a subepithelial connective tissue graft (SCTG) or an acellular dermal matrix (ADM) on reducing tissue alterations at an immediate implant site.

MATERIALS AND METHODS

This trial had three groups: (i) immediate implant with SCTG (ICT group); (ii) immediate implant with ADM (IAD group); (iii) immediate implant without STA (control group). Forty-six patients were randomly assigned to each group. Implants were placed at the maxillary anterior or premolar areas and restored after the 6-month visit. Clinical outcomes, including buccal soft-tissue contour, peri-implant mucosal level, soft-tissue thickness and keratinized tissue width, were measured at baseline and at 3-, 6- and 12-month follow-up visits. Radiographic bone levels were measured at baseline and at 6- and 12-month follow-up visits. Patient-reported outcomes were also collected.

RESULTS

STA procedures increased peri-implant mucosal thickness and maintained buccal soft-tissue contours. Compared to the control group, STA groups did not prevent peri-implant mucosal recession or interproximal bone resorption. Generally, no significant differences in clinical outcomes were detected between the ICT and IAD groups. Most patients were highly satisfied with the immediate implant procedure and outcomes without significant differences between groups.

CONCLUSIONS

STA at immediate implant sites enhanced soft-tissue thickness and maintained soft-tissue contours but did not prevent peri-implant mucosal recession or interproximal bone resorption. Long-term follow-up should be performed since these results were reported for only up to 1 year.

Soft tissue augmentation with a volume-stable collagen matrix or an autogenous connective tissue graft at implant sites: Five-year results of a randomized controlled trial post implant loading

BACKGROUND

Interventions to augment the mucosal thickness around dental implants are indicated to optimize esthetics and maintain peri-implant health. However, there is a lack of clinical data on the long-term performance of soft tissue substitutes, such as volume-stable collagen matrix (VCMX), compared to autogenous grafts, such as subepithelial connective tissue grafts (SCTGs). This randomized controlled trial aimed to assess 5-year data on clinical and radiographic outcomes at implant sites previously augmented with VCMX or SCTG.

METHODS

Twenty patients were randomly assigned for soft tissue augmentation with VCMX or SCTG at single implant sites. Following abutment connection, final restorations were inserted (baseline; BL) and patients were reexamined up to 5 years (FU-5). Measurements included clinical data, marginal bone levels, mucosal thickness, and ridge contour changes. Nonparametric tests and estimates were applied for the statistical analysis.

RESULTS

The median buccal mucosal thickness increased by 0.3 mm (Q1: -0.8; Q3: 1.0) in the VCMX group (P = 0.656) and 0.3 mm (Q1: 0.0; Q3: 1.0) in the SCTG group (P = 0.188) between BL and FU-5 (intergroup P = 0.752), while the ridge contour decreased by a median of -0.3 mm (-0.9; -0.1) (P = 0.078) for VCMX and -0.3 mm (-0.4; -0.2) (P = 0.039) for SCTG (intergroup P = 0.817). Peri-implant health was maintained in both groups with stable clinical and radiographic outcomes and without significant differences between the treatments.

CONCLUSION

Despite the limited power and considerable dropout rate in the present study, soft tissue augmentation at implant sites with either VCMX or SCTG resulted in similar stable peri-implant tissues, favorable esthetics, and clinically negligible contour changes at 5 years post loading.