Comparison of Two Differently Processed Acellular Dermal Matrix Products for Root Coverage Procedures: A Prospective, Randomized Multicenter Study

Polymer-Based Scaffolds as an Implantable Material in Regenerative Dentistry: A Review

Polymer-based scaffolds have emerged as transformative materials in regenerative dentistry, enabling the restoration and replacement of dental tissues through tissue engineering approaches. These scaffolds, derived from natural and synthetic polymers, mimic the extracellular matrix to promote cellular attachment, proliferation, and differentiation. Natural polymers such as collagen, chitosan, and alginate offer biocompatibility and bioactivity, while synthetic alternatives like polylactic acid (PLA) and polycaprolactone (PCL) provide tunable mechanical properties and degradation rates. Recent advancements highlight the integration of bioactive molecules and nanotechnology to enhance the regenerative potential of these materials. Furthermore, developing hybrid scaffolds combining natural and synthetic polymers addresses biocompatibility and mechanical strength challenges, paving the way for patient-specific treatments. Innovations in 3D bioprinting and stimuli-responsive biomaterials are expected to refine scaffold design further, improving therapeutic precision and clinical outcomes. This review underscores the critical role of polymer-based scaffolds in advancing regenerative dentistry, focusing on their applications, advantages, and limitations.

Human Acellular Collagen Matrices-Clinical Opportunities in Tissue Replacement

The field of regenerative medicine is increasingly in need of effective and biocompatible materials for tissue engineering. Human acellular dermal matrix (hADM)-derived collagen matrices stand out as a particularly promising candidate. Their ability to preserve structural integrity, coupled with exceptional biocompatibility, positions them as a viable choice for tissue replacement. However, their clinical application has been largely confined to serving as scaffolds. This study aims to expand the horizon of clinical uses for collagen sheets by exploring the diverse cutting-edge clinical demands. This review illustrates the clinical utilizations of collagen sheets beyond traditional roles, such as covering skin defects or acting solely as scaffolds. In particular, the potential of Epiflex®, a commercially available and immediately clinically usable allogeneic membrane, will be evaluated. Collagen sheets have demonstrated efficacy in bone reconstruction, where they can substitute the induced Masquelet membrane in a single-stage procedure, proving to be clinically effective and safe. The application of these membranes allow the reconstruction of substantial tissue defects, without requiring extensive plastic reconstructive surgery. Additionally, they are found to be apt for addressing osteochondritis dissecans lesions and for ligament reconstruction in the carpus. The compelling clinical examples showcased in this study affirm that the applications of human ADM extend significantly beyond its initial use for skin defect treatments. hADM has proven to be highly successful and well-tolerated in managing various etiologies of bone and soft tissue defects, enhancing patient care outcomes. In particular, the application from the shelf reduces the need for additional surgery or donor site defects.

Acellular dermal matrix for the treatment of multiple gingival recession defects associated with carious and previously restored cervical lesions: A case report with 10 years of follow-up

BACKGROUND

Limited evidence exists on the outcome of the modified coronally advanced tunnel (MCAT) with acellular dermal matrix (ADM) for the treatment of gingival recession defects (GRD) especially when complicated by restored cervical lesions. Therefore, the aim of this case report was to assess the short- and long-term clinical outcomes of maxillary Type 1 recession defects (RT1) associated with restored cervical lesions treated with MCAT with ADM.

METHODS AND RESULTS

A 43-year-old female patient, presented with multiple adjacent RT1 recessions in the left maxilla, previously treated with overhanging cervical resin restorations. The case was approached with a careful evaluation of the diagnostic determinants of root coverage, removal of the aberrant resin restorations, treatment with MCAT with ADM, and periodical evaluation over a follow-up of 10 years. The treatment was followed by complete root coverage, improvement of gingival phenotype, and perfect root coverage esthetic score. Outcomes were periodically assessed and were maintained over 10 years of follow-up.

CONCLUSION

MCAT with ADM is an effective technique for the treatment of multiple GRD complicated by cervical restorations. Complete root coverage and excellent esthetic outcomes were obtained and maintained in the long term.

Influence of immediate postoperative gingival thickness and gingival margin position on the outcomes of root coverage therapy: A 6 months prospective case series study using 3D digital measuring methods

BACKGROUND

To assess linear and volumetric changes following the treatment of gingival recessions (GRs) by means of a modified coronally advanced tunnel technique combined with acellular dermal matrix (MTUN + ADM).

MATERIALS AND METHODS

Patients presenting GR type 1 (RT1) GRs underwent root coverage surgery consisting of MTUN + ADM. Clinical measurements were made, and intraoral scans were obtained at baseline, postoperatively, and 6 weeks, 3 and 6 months after surgery, to evaluate changes in probing depth (PD), keratinized tissue width (KTW), recession depth (RD), recession area (RA), marginal gingival thickness (MGT), and mucosal volume (MV). The impact of patient-level and surgical-site variables upon percentage root coverage (% RC) and the likelihood of achieving complete root coverage (CRC) were explored.

RESULTS

A total of 20 patients (n = 47 teeth) were treated. After 6 months, RD and RA decreased, while KTW, MGT, and MV increased. The mean % RC was 93% at 6 months and CRC was found on 72.3% of the sites at 6 months. The postoperative MGT changes at 1.5 and 3 mm were significantly correlated to % RC and CRC at 6 months. Each additional mm of postoperative gain of gingival thickness resulted in a 4-fold increase in the probability of achieving CRC. Additionally, gingival margin positioned ≥0.5 mm coronal to the cementoenamel junction immediately after surgery was a strong predictor of CRC.

CONCLUSIONS

The MGT gain at 1.5 and 3 mm achieved in the immediate postoperative period is a significant predictor of CRC at 6 months when treating multiple GRs via MTUN + ADM.

CLINICAL SIGNIFICANCE

The Scientific rationale for the study relies on the lack of 3D digital measuring tools in the assessment of soft tissue healing dynamics after root coverage therapy. The principal findings of this study can be summarized as follows: tooth type, tooth position, and post-operative gingival margin position and gingival thickness and volume changes are predictors of CRC. Therefore, the practical implications are that the more thickness and more coronal advancement achieved immediately after root coverage surgery, the higher chance of achieving CRC.

Hydrogel-Based Biomaterial as a Scaffold for Gingival Regeneration: A Systematic Review of In Vitro Studies

BACKGROUND

Hydrogel is considered a promising scaffold biomaterial for gingival regeneration. In vitro experiments were carried out to test new potential biomaterials for future clinical practice. The systematic review of such in vitro studies could synthesize evidence of the characteristics of the developing biomaterials. This systematic review aimed to identify and synthesize in vitro studies that assessed the hydrogel scaffold for gingival regeneration.

METHODS

Data on experimental studies on the physical and biological properties of hydrogel were synthesized. A systematic review of the PubMed, Embase, ScienceDirect, and Scopus databases was conducted according to the Preferred Reporting System for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement guidelines. In total, 12 original articles on the physical and biological properties of hydrogels for gingival regeneration, published in the last 10 years, were identified.

RESULTS

One study only performed physical property analyses, two studies only performed biological property analyses, and nine studies performed both physical and biological property analyses. The incorporation of various natural polymers such as collagen, chitosan, and hyaluronic acids improved the biomaterial characteristics. The use of synthetic polymers faced some drawbacks in their physical and biological properties. Peptides, such as growth factors and arginine-glycine-aspartic acid (RGD), can be used to enhance cell adhesion and migration. Based on the available primary studies, all studies successfully present the potential of hydrogel characteristics in vitro and highlight the essential biomaterial properties for future periodontal regenerative treatment.

Soft tissue phenotype modification predicts gingival margin long-term (10-year) stability: Longitudinal analysis of six randomized clinical trials

Aim

To assess the prognostic value of soft tissue phenotype modification following root coverage procedures for predicting the long‐term (10‐year) behaviour of the gingival margin.

Materials and Methods

Participants from six randomized clinical trials on root coverage procedures at the University of Michigan were re‐invited for a longitudinal evaluation. Clinical measurements were obtained by two calibrated examiners. A data‐driven approach to model selection with Akaike information criterion (AIC) was carried out via multilevel regression analyses and partial regression plotting for changes in the level of the gingival margin over time and interactions with the early (6‐month) results of soft tissue phenotypic modification.

Results

One‐hundred and fifty‐seven treated sites in 83 patients were re‐assessed at the long‐term recall. AIC‐driven model selection and regression analyses demonstrated that 6‐month keratinized tissue width (KTW) and gingival thickness (GT) influenced the trajectory of the gingival margin similarly in a concave manner; however, GT was the driving determinant that predicted significantly less relapse in the treatments, with stability of the treated gingival margin obtained beyond values of 1.46 mm.

Conclusions

Among a compliant patient cohort, irrespective of the rendered therapy, the presence of at least 1.5 mm KTW and 1.46 mm GT was correlated with the long‐term stability of the gingival margin.

Effectiveness of acellular dermal matrix graft with a coronally advanced flap for the treatment of Miller Class I/II single gingival recession with thin gingival phenotype: study protocol for a split-mouth randomised controlled trial

INTRODUCTION

Gingival recession is one of the most common mucogingival deformities requiring surgical correction. The American Academy of Periodontology Regeneration Workshop recommended connective tissue graft (CTG) combined with coronally advanced flap (CAF) for the treatment of Miller Class I and II single-tooth gingival recession. The disadvantages of harvesting autogenous tissue include postoperative bleeding, pain and discomfort at the donor site, restricted tissue supply, increased morbidity and prolonged operative times. Acellular dermal matrix (ADM) contains undamaged collagen and elastin matrices that can be used as a substitute for CTG during root coverage procedures. However, the use of ADM is still controversial. The objective of this split-mouth; randomised, controlled, clinical study is to evaluate the long-term effects of ADM graft (ADMG) combined with CAF on root coverage, aesthetics and patient satisfaction for the treatment of single gingival recession with thin gingival phenotype.

METHODS AND ANALYSIS

Forty participants with bilateral Miller Class I/II gingival recession will be randomised to receive an ADMG on one side and CTG on the contralateral side, combined with CAF. Gingival recession depth, gingival recession width and keratinised tissue width will be measured at baseline, 2 weeks and 1, 3, 6, 12 and 24 months. Mean root coverage, complete root coverage, root coverage aesthetic score, colour change (∆E) and patient satisfaction will be assessed during follow-up visits.

ETHICS AND DISSEMINATION

The present study has received approval from the Ethics Committee of Peking University School and Hospital of Stomatology (PKUSSIRB-202054029). Data of this study will be registered with the International Clinical Trials Registry Platform. Additionally, we will disseminate the results through scientific journal.

TRIAL REGISTRATION NUMBER

ChiCTR2000033230.

Stability of biomaterials used in adjunct to coronally advanced flap: A systematic review and network meta-analysis

AIM

The objective of this network meta-analysis was to rank different biomaterials used in adjunct to coronally advanced flap (CAF), based on their performance in root-coverage for Miller's Class I and II gingival recessions.

MATERIALS AND METHODS

An electronic database search was carried out in PUBMED, CENTRAL, SCOPUS, and EMBASE to identify the eligible articles and compiled into the citation manager to remove the duplicates. The primary outcome was keratinized gingival tissue width (KGW) and percentage of root coverage (%RC). The treatment effect of different biomaterials was estimated using predictive interval plots and ranked based on biomaterials performance, using multidimensional scale ranking.

RESULTS

CAF + connective tissue graft (CTG), CAF + platelet concentrate matrix (PCM) and acellular dermal matrix (ADM) ranked at the top positions in performance in improving KGW. The highest ranked materials in improving percentage of root coverage in gingival recession were CAF + collagen matrix (CM) + gingival fibroblasts (GF), CAF + ADM + platelet rich plasma (PRP) and CAF + ADM, as compared to CAF alone.

CONCLUSION

CTG, ADM, platelet concentrates, and CM + GFs, when used in adjunct to CAF, showed improved stability over ≥12 months of follow-up, better percentage of root coverage, and improved keratinized gingival width.

Polymeric Scaffolds for Dental, Oral, and Craniofacial Regenerative Medicine

Dental, oral, and craniofacial (DOC) regenerative medicine aims to repair or regenerate DOC tissues including teeth, dental pulp, periodontal tissues, salivary gland, temporomandibular joint (TMJ), hard (bone, cartilage), and soft (muscle, nerve, skin) tissues of the craniofacial complex. Polymeric materials have a broad range of applications in biomedical engineering and regenerative medicine functioning as tissue engineering scaffolds, carriers for cell-based therapies, and biomedical devices for delivery of drugs and biologics. The focus of this review is to discuss the properties and clinical indications of polymeric scaffold materials and extracellular matrix technologies for DOC regenerative medicine. More specifically, this review outlines the key properties, advantages and drawbacks of natural polymers including alginate, cellulose, chitosan, silk, collagen, gelatin, fibrin, laminin, decellularized extracellular matrix, and hyaluronic acid, as well as synthetic polymers including polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), poly (ethylene glycol) (PEG), and Zwitterionic polymers. This review highlights key clinical applications of polymeric scaffolding materials to repair and/or regenerate various DOC tissues. Particularly, polymeric materials used in clinical procedures are discussed including alveolar ridge preservation, vertical and horizontal ridge augmentation, maxillary sinus augmentation, TMJ reconstruction, periodontal regeneration, periodontal/peri-implant plastic surgery, regenerative endodontics. In addition, polymeric scaffolds application in whole tooth and salivary gland regeneration are discussed.

An in vivo comparison of wound healing characteristics of two commercial acellular dermal matrices

Objectives

Many acellular dermal matrices (ADMs) are available for use in periodontal surgical procedures. However, few studies exist evaluating their in vivo healing properties. The objectives of this study were to compare the wound healing and remodeling of two ADMs used for gingival augmentation procedures in the rat model.

Materials and methods

This was a nonrandomized controlled split‐mouth study. Envelope flaps were surgically created in the maxillary quadrants of 24 Sprague Dawley rats. Each received either (a) AlloDerm Regenerative Tissue Matrix, or (b) OrACELL. Gingival tissue from one mandibular quadrant served as the untreated control. Six male and six female rats were treated for 7 or 21 days. Biopsies were processed for histologic analysis (H&E, Picro‐sirius red, Verhoeff's solution) or RNA analysis (RT‐PCR) to analyze the expression of type I collagen (Col1a1), fibronectin (Fn‐1) and VEGF‐A (Vegf‐A).

Results

There was a greater density of fibroblasts in OrACELL compared to AlloDerm at both timepoints. There was a greater density of elastin present in AlloDerm compared to OrACELL at 7 days but no differences at 21 days. There were no differences between test groups in the percentage of birefringent collagen or in the expression of Vegf‐A or Fn‐1. At 7 days, there were significantly more fibroblasts for males in the OrACELL group compared to females. At 21 days, there was a significantly greater expression of Col1a1 for males in the OrACELL group compared to females.

Conclusions

Early wound healing and remodeling of OrACELL appeared to occur more rapidly than AlloDerm and was accelerated in male rats. Whether these results have clinical implications for soft tissue grafting procedures in humans remains to be determined.

Patient experience of autogenous soft tissue grafting has an implication for future treatment: A 10- to 15-year cross-sectional study

BACKGROUND

Patient-reported outcomes have received a great deal of interest in periodontal plastic procedures. However, their evaluation has mainly been short-term. Thus, the aim of this study was to evaluate the impact of soft tissue grafting procedures conducted over a decade ago on the willingness of a patients to undergo the surgery again.

METHODS

Subjects that received an autogenous soft tissue graft over 10 years ago were screened and invited for a survey. Their response was only analyzed if they were able to correctly identify the sites of the surgical procedures. Dichotomous questions and visual analogue scales (VASs) were used to assess self-reported pain, willingness to retreat and satisfaction.

RESULTS

Fifty-two patients were included in the analyses. Higher pain was reported for mandibular sites, and treated areas including ≥ 3 teeth (P < 0.01). Willingness to retreatment was 84.6% and it was negatively associated with self-reported pain measures, the arch location (mandible), and number of treated sites (≥3 teeth) (P < 0.01). Mean satisfaction rate was 86.9 ± 13.65 (VAS) and showed a positive correlation with willingness to retreat (P < 0.01). Having a complete root coverage at the recall visit was also significantly associated with higher patient satisfaction scores (P < 0.01).

CONCLUSIONS

Patient experience of previous autogenous soft tissue grafting has an influence on their decision to undergo future treatment. Willingness to retreat was negatively affected by mandibular sites, larger treated areas and the perceived pain, while presenting with complete root coverage was significantly associated with patient satisfaction.

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

BACKGROUND

The long-term outcomes of acellular dermal matrix (ADM) for the treatment of isolated gingival recessions has not yet been evaluated. Thus, the aim of this study was to observe the root coverage outcomes of coronally advanced flap with ADM over time, and compare them with their adjacent untreated sites.

METHODS

Twelve patients (from 20) were available at the 9-year recall. Clinical parameters (recession depth, mean root coverage [mRC], keratinized tissue width [KTW], and gingival thickness) were evaluated and compared with the 1-year results, and the ADM-adjacent untreated sites (on mesial and distal) via mixed-modeling regression analyses.

RESULTS

From 1 to 9 years, the ADM-treated isolated recessions showed a relapse from 77% to 62% mRC (P <0.05). A similar pattern toward apical shift of the gingival margin was noticed for the ADM-adjacent untreated sites without baseline recession. However, ADM-adjacent untreated sites which had presented with recession at baseline but were not treated showed a significantly more apical shift of the gingival margin (almost two-fold). A significant increase in KTW was noted for all sites. Baseline KTW ≥2 mm was a significant predictor for the stability of the gingival margin at the ADM-treated, and the ADM-adjacent sites with baseline recession.

CONCLUSIONS

ADM-treated sites displayed recession relapse from 1 to 9 years. The untreated adjacent sites with a recession at baseline, showed a higher apical displacement of the gingival margin compared with the ADM-treated sites, and ADM-adjacent sites without a recession at baseline.

Adsorption and Release of Growth Factors from Four Different Porcine-Derived Collagen Matrices

Xenogeneic acellular collagen matrices represent a safe alternative to autologous soft tissue transplants in periodontology and implant dentistry. Here, we aimed to investigate the adsorption and release of growth factors from four porcine-derived collagen matrices using enzyme-linked immunosorbent assay. Non-crosslinked collagen matrix (NCM), crosslinked collagen matrix (CCM), dried acellular dermal matrix (DADM), and hydrated acellular dermal matrix (HADM) adsorbed each of the following growth factors, TGF-β1, FGF-2, PDGF-BB, GDF-5 and BMP-2, with an efficiency close to 100%. Growth factor release for a 13-day period was in the range of 10-50% of the adsorbed protein, except for the BMP-2 release that was in the range of 5-7%. Generally, protein release occurred in two phases. Phase I was arbitrary defined by the highest release from the matrices, usually within 24 h. Phase II, spanning the period immediately after the peak release until day 13, corresponded to the delayed release of the growth factors from the deeper layers of the matrices. HADM showed significantly (P < 0.001) higher TGF-β1, FGF-2, and PDGF-BB release in phase II, compared to the rest of the matrices. NCM exhibited significantly (P < 0.001) higher FGF-2 release in phase II, compared to CCM and DADM as well as a characteristic second peak in PDGF-BB release towards the middle of the tested period. In contrast to NCM and HADM, CCM and DADM showed a gradual and significantly higher release of GDF-5 in the second phase. Several burst releases of BMP-2 were characteristic for all matrices. The efficient adsorption and sustained protein release in the first 13 days, and the kinetics seen for HADM, with a burst release within hours and high amount of released growth factor within a secondary phase, may be beneficial for the long-term tissue regeneration following reconstructive periodontal surgery.

Comparison of two soft tissue substitutes for the treatment of gingival recession defects: an animal histological study

Objectives:

This study aimed to compare two different soft tissue replacement grafts in their ability to treat gingival recession defects and successfully integrate with the surrounding tissues.

Methodology:

Nine beagle dogs were included and followed up to 10 weeks. Sites for intervention were allocated to one of the grafting materials investigated. Treatment consisted of coronally advanced flap combined with one of the two soft tissue substitutes on a previous surgically created defect. Materials employed were porcine-derived acellular dermal matrix (ADM) [Novomatrix^™ (Test)] and collagen-based matrix (CBM) [Mucograft^® (Control)]. Animals were sacrificed at 2, 6, and 10 weeks postoperatively and compared using descriptive histology and histomorphometric outcomes.

Results:

Macroscopic findings were similar between test and control groups at all intervals. After 10 weeks, both groups demonstrated successful incorporation of the grafting materials without signs of rejection and with comparable tissue integration. The histomorphometric data were similar between groups at 2 weeks; however, the test group provided greater root coverage and increase in tissue thickness than the control at 6- and 10-weeks post surgically.

Conclusions:

Both porcine-derived ADM and CBM revealed similar histological outcomes with successful integration and absence of adverse events. Test group provided superior outcomes regarding root coverage and increase in tissue thickness.

The Effect of Time on Root Coverage Outcomes: A Network Meta-analysis

The stability of root coverage outcomes has gained a great deal of interest. However, insufficient evidence is available, mainly due to limited direct comparisons among different techniques and the small sample size among clinical trials. Therefore, the aim of this study was to propose a mixed-models network meta-analysis (NMA) that includes the novelty of assessing time on root coverage outcomes while simultaneously comparing different surgical approaches. A literature search was performed by 2 individual reviewers to identify randomized clinical trials (RCTs) reporting the outcomes of root coverage procedures of at least 2 time points to estimate the slopes of different treatment approaches. The primary outcomes were the changes in slopes for recession depth (REC), keratinized tissue width (KTW), and clinical attachment level. Sixty RCTs with a total of 2,554 gingival recessions (1,864 patients) were included in the NMA. Connective tissue graft (CTG) and enamel matrix derivative (EMD) approaches provided superior initial REC reduction compared to flap advancement alone. However, only CTG-based procedures were effective in maintaining the stability of the gingival margin over time, while EMD, acellular dermal matrix, collagen matrix, and flap alone showed a similar tendency for gingival recession recurrence. Baseline REC and KTW at the earliest postoperative recall were predictors for the stability of the gingival margin. In addition, a geographic center effect on the treatment slopes was observed for REC and KTW. While limitations of the present linear mixed-modeling approach should be considered as it refers to estimation and comparison of time slopes based on an examined while linear framework, the designed NMA showed to be an effective tool for the simultaneous comparison of multiple treatment approaches while taking into account the critical element of time.

Extracellular matrix-based scaffolding technologies for periodontal and peri-implant soft tissue regeneration

The present article focuses on the properties and indications of scaffold-based extracellular matrix (ECM) technologies as alternatives to autogenous soft tissue grafts for periodontal and peri-implant plastic surgical reconstruction. The different processing methods for the creation of cell-free constructs resulting in preservation of the extracellular matrices influence the characteristics and behavior of scaffolding biomaterials. The aim of this review is to discuss the properties, clinical application, and limitations of ECM-based scaffold technologies in periodontal and peri-implant soft tissue augmentation when used as alternatives to autogenous soft tissue grafts.

Acellular dermal matrix and coronally advanced flap or tunnel technique in the treatment of multiple adjacent gingival recessions. A 12-year follow-up from a randomized clinical trial

AIM

To evaluate the long-term outcomes of Acellular Dermal Matrix (ADM) with Coronally Advanced Flap (CAF) or Tunnel technique (TUN) in the treatment of multiple adjacent gingival recessions (MAGRs).

MATERIAL AND METHODS

Nineteen of the original 24 patients contributing to a total number of 33 sites for CAF and 34 for TUN were available for the 12 years follow-up examination. Recession depth, mean root coverage (mRC), keratinized tissue width (KTW), gingival thickness (GT) were evaluated and compared with baseline values and 6-months results. Regression analysis was performed to identify factors related to the stability of the gingival margin.

RESULTS

A highly significant drop in mRC was observed for both groups from the 6 months timepoint to the 12 years recall (p < .001). While there were no statistically significant differences between the two groups in terms of Clinical Attachment Level (CAL), KTW, GT changes and Root Coverage Esthetic Score at each timepoint (p > .05). KTW ≥ 2 mm and GT ≥ 1.2 mm at 6-months were two predictors for stability of the gingival margin (p = .03 and p = .01, respectively).

CONCLUSIONS

A significant relapse of the gingival margin of MAGRs treated with CAF or TUN + ADM was observed after 12 years.

Root coverage procedures for treating localised and multiple recession-type defects

BACKGROUND

Gingival recession is defined as the oral exposure of the root surface due to a displacement of the gingival margin apical to the cemento-enamel junction and it is regularly linked to the deterioration of dental aesthetics. Successful treatment of recession-type defects is based on the use of predictable root coverage periodontal plastic surgery (RCPPS) procedures. This review is an update of the original version that was published in 2009.

OBJECTIVES

To evaluate the efficacy of different root coverage procedures in the treatment of single and multiple recession-type defects.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 15 January 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 12) in the Cochrane Library (searched 15 January 2018), MEDLINE Ovid (1946 to 15 January 2018), and Embase Ovid (1980 to 15 January 2018). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials (15 January 2018). No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) only of at least 6 months' duration evaluating recession areas (Miller's Class I or II ≥ 3 mm) and treated by means of RCPPS procedures.

DATA COLLECTION AND ANALYSIS

Screening of eligible studies, data extraction and risk of bias assessment were conducted independently and in duplicate. Authors were contacted for any missing information. We expressed results as random-effects models using mean differences (MD) for continuous outcomes and odds ratios (OR) for dichotomous outcomes with 95% confidence intervals (CI). We used GRADE methods to assess the quality of the body of evidence of our main comparisons.

MAIN RESULTS

We included 48 RCTs in the review. Of these, we assessed one as at low risk of bias, 12 as at high risk of bias and 35 as at unclear risk of bias. The results indicated a greater reduction in gingival recession for subepithelial connective tissue grafts (SCTG) + coronally advanced flap (CAF) compared to guided tissue regeneration with resorbable membranes (GTR rm) + CAF (MD -0.37 mm; 95% CI -0.60 to -0.13, P = 0.002; 3 studies; 98 participants; low-quality evidence). There was insufficient evidence of a difference in gingival recession reduction between acellular dermal matrix grafts (ADMG) + CAF and SCTG + CAF or between enamel matrix protein (EMP) + CAF and SCTG + CAF. Regarding clinical attachment level changes, GTR rm + CAF promoted additional gains compared to SCTG + CAF (MD 0.35; 95% CI 0.06 to 0.63, P = 0.02; 3 studies; 98 participants; low-quality evidence) but there was insufficient evidence of a difference between ADMG + CAF and SCTG + CAF or between EMP + CAF and SCTG + CAF. Greater gains in the keratinized tissue were found for SCTG + CAF when compared to EMP + CAF (MD -1.06 mm; 95% CI -1.36 to -0.76, P < 0.00001; 2 studies; 62 participants; low-quality evidence), and SCTG + CAF when compared to GTR rm + CAF (MD -1.77 mm; 95% CI -2.66 to -0.89, P < 0.0001; 3 studies; 98 participants; very low-quality evidence). There was insufficient evidence of a difference in keratinized tissue gain between ADMG + CAF and SCTG + CAF. Few data exist on aesthetic condition change related to patients' opinion and patients' preference for a specific procedure.

AUTHORS' CONCLUSIONS

Subepithelial connective tissue grafts, coronally advanced flap alone or associated with other biomaterial and guided tissue regeneration may be used as root coverage procedures for treating localised or multiple recession-type defects. The available evidence base indicates that in cases where both root coverage and gain in the width of keratinized tissue are expected, the use of subepithelial connective tissue grafts shows a slight improvement in outcome. There is also some weak evidence suggesting that acellular dermal matrix grafts appear as the soft tissue substitute that may provide the most similar outcomes to those achieved by subepithelial connective tissue grafts. RCTs are necessary to identify possible factors associated with the prognosis of each RCPPS procedure. The potential impact of bias on these outcomes is unclear.

Papilla and pontic area regeneration in patient with gingival smile: A clinical case

Purpose

Connective tissue grafts are widely documented as a predictable technique for treating Miller Class I and II recessions, as well as procedures in which soft tissue augmentation is required for aesthetic reasons. This article aims to explore the resolution of a clinical case with this type of problema.

Clinical case

This case describes a technique for reconstructing a pontic area and adjacent papilla by means of two consecutive connective tissue grafts. The first graft served to increase the amount of tissue in the horizontal direction, and the second promoted vertical reconstruction of the defect.

Results and Conclusion

In cases with aesthetic requirements, restorative intervention may be able to mask tissue loss, but it can hardly achieve optimal aesthetic results. Periodontal plastic surgery techniques can be used to achieve that ideal result. The clinician must diagnose conditions in order to select correct treatment regimen for each individual case. Key words:Papilla, gingival smile, pontic, restorative dentistry.

Acellular dermal matrix and subepithelial connective tissue grafts for root coverage: A systematic review

BACKGROUND

The aim of this systematic review was to evaluate whether patients with gingival recession would benefit from an acellular dermal matrix graft (ADMG) in ways that are comparable to the gold standard of the subepithelial connective tissue graft (SCTG).

MATERIALS AND METHODS

A systematic review and meta-analysis comparing ADMG to SCTG for the treatment of Miller Class I and II recession defects was conducted according to PRISMA guidelines. PubMed, Excerpta Medica Database, and Cochrane Central Register of Controlled Trials databases were searched up to March 2016 for controlled trials with minimum 6 months duration. The primary outcome was root coverage; secondary outcomes included attachment level change, keratinized tissue (KT) change, and patient-based outcomes. Both authors independently assessed the quality of each included trial and extracted the relevant data.

RESULTS

From 158 potential titles, 17 controlled trials were included in the meta-analysis. There were no differences between ADMG and SCTG for mean root coverage, percent root coverage, and clinical attachment level gain. ADMG was statistically better than SCTG for gain in width of KT (-0.43 mm; 95% confidence interval: -0.72, -0.15). Only one study compared patient-based outcomes.

CONCLUSION

This review found that an ADMG would be a suitable root coverage substitute for an SCTG when avoidance of the second surgical site is preferred.

Histologic Evaluation of Acellular Dermal Matrix Allografts in Humans

INTRODUCTION

Acellular dermal matrix (ADM) is a cell-free dermal matrix comprised of a structurally integrated basement membrane complex and extracellular matrix in which collagen bundles and elastic fibers are the main components. There are several commercially available ADM allografts that have different processing methods. This case series reports the histologic presentation of two of the most widely used ADM allografts, referred to as ADM-A and ADM-B, in patients that had specific situations involving reentry.

CASE SERIES

Two patients referred to the Louisiana State University Department of Periodontics, New Orleans, Louisiana, with 1- to 3-mm recession of at least two non-contiguous sites needing soft tissue augmentation, were treated with appropriate mucogingival procedures using ADM-A or ADM-B. After ≈6 to 8 months of healing, and due to clinical findings that necessitated further periodontal procedures, small tissue biopsies were obtained and examined microscopically.

CONCLUSIONS

All samples of ADM (A and B) analyzed after staining with hematoxylin and eosin had a generally similar appearance under light microscopic examination, which suggests they are both well incorporated into native tissues after 6 to 8 months of healing. When stained with Verhoeff-Van Gieson, all samples showed elastin fibers, a finding consistent with previously published light microscopic observations of ADM. There appeared to be a more densely packed elastin pattern in the deep base of ADM-A compared with ADM-B. This might be an indication these two materials have a different healing pathway when used to augment the oral mucosa.

Does Adjunctive Use of Growth Factors Improve Clinical Outcomes of Soft Tissue Grafting at Miller Class III Recession Defects? A Review of Current Evidence

Focused Clinical Question In patients with gingival recession that is classified as Miller Class III, does adjunctive use of local growth factors with gingival grafting procedures improve clinical outcomes? Clinical Scenario A 31-year-old female presents with a chief complaint of gingival recession (GR) at teeth #4 to #13 (Fig. 1). Interproximal bone loss coronal to the level of the buccal GR is present. She is concerned about esthetics and would like to maximize her chance for complete root coverage. Her medical history is non-contributory, and she has no contraindications to routine dental care. Because of the number of teeth involved and the difficulty in harvesting autogenous tissues, she is treated with acellular dermal matrix^§ and enamel matrix derivative^‖ with a coronally advanced flap at teeth #4 to #13 (Figs. 2 and 3). Final results reveal significant root coverage on all teeth and complete root coverage on teeth #7 to #10. This results in an esthetically acceptable result (Fig. 4).