Evaluation of recession defects treated with coronally advanced flaps and either recombinant human platelet-derived growth factor-BB plus β-tricalcium phosphate or connective tissue: comparison of clinical parameters at 5 years

Twenty-five years of recombinant human growth factors rhPDGF-BB and rhBMP-2 in oral hard and soft tissue regeneration

Contemporary oral tissue engineering strategies involve recombinant human growth factor approaches to stimulate diverse cellular processes including cell differentiation, migration, recruitment, and proliferation at grafted areas. Recombinant human growth factor applications in oral hard and soft tissue regeneration have been progressively researched over the last 25 years. Growth factor-mediated surgical approaches aim to accelerate healing, tissue reconstruction, and patient recovery. Thus, regenerative approaches involving growth factors such as recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and recombinant human bone morphogenetic proteins (rhBMPs) have shown certain advantages over invasive traditional surgical approaches in severe hard and soft tissue defects. Several clinical studies assessed the outcomes of rhBMP-2 in diverse clinical applications for implant site development and bone augmentation. Current evidence regarding the clinical benefits of rhBMP-2 compared to conventional therapies is inconclusive. Nevertheless, it seems that rhBMP-2 can promote faster wound healing processes and enhance de novo bone formation, which may be particularly favorable in patients with compromised bone healing capacity or limited donor sites. rhPDGF-BB has been extensively applied for periodontal regenerative procedures and for the treatment of gingival recessions, showing consistent and positive outcomes. Nevertheless, current evidence regarding its benefits at implant and edentulous sites is limited. The present review explores and depicts the current applications, outcomes, and evidence-based clinical recommendations of rhPDGF-BB and rhBMPs for oral tissue regeneration.

Long-term stability of gingival margin and periodontal soft-tissue phenotype achieved after mucogingival therapy: A systematic review

BACKGROUND

The aim of this systematic review was two-fold: (i) to evaluate the long-term (≥5 years) stability of the gingival margin position, keratinized tissue width (KTW) and gingival thickness (GT) in sites that underwent root coverage (RC) or gingival augmentation (GA); and (ii) to assess the influence of different local variables on the long-term stability of dental and gingival tissues.

MATERIALS AND METHODS

Randomized controlled trials (RCTs) and non-RCTs reporting short-term (i.e., 6-12 months after baseline surgical intervention) and long-term (≥5 years) follow-up data after surgical treatment of adult patients presenting single or multiple mucogingival deformities, defined as sites presenting gingival recession defects (GRDs) and/or (KTW) deficiency (i.e., <2 mm), were considered eligible for inclusion. MEDLINE-PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases were searched for articles published up to 15 May 2023. Mixed-effects multiple linear regression was used to assess the association between KTW, type of surgical procedure and time (i.e., independent variables) on the stability of the gingival margin in sites that received RC or GA therapy.

RESULTS

Of the 2569 potentially eligible records, 41 (reporting 40 studies) met the eligibility criteria. Graphical estimates including data from all RC procedures found an upward trend in recession depth (RD) increase over time. Conversely, it was observed that in 63.63% of RC studies and in 59.32% of RC treatment arms KTW increased over time, particularly in sites treated with subepithelial connective tissue grafts (SCTGs). Conversely, sites that underwent GA procedures generally exhibited an overall reduction of KTW over time. However, sites treated with free gingival grafts (FGGs) showed a decrease in RD after 10 years of follow-up. Three main findings derived from the pooled estimates were identified: (i) Gingival margin stability was associated with the amount of KTW present during short-term assessment (i.e. the greater the KTW at 6-12 months after treatment, the more stable the gingival margin). (ii) The use of autogenous soft-tissue grafts was associated with lower RD increase over time. (iii) Treatment approaches that contribute to the three-dimensional enhancement of the gingival phenotype, as clearly demonstrated by FGG, were associated with gingival margin stability.

CONCLUSIONS

The extent of apical migration of the gingival margin appears to be directly related to the amount of KTW and GT upon tissue maturation. Interventions involving the use of autogenous grafts, either SCTG or FGG, are associated with greater short-term KTW gain and lower RD increase over time.

Comparative evaluation of pinhole surgical technique with and without A-PRF in the treatment of multiple adjacent recession defects: A clinico radiographic study

BACKGROUND

To evaluate and compare efficacy of pinhole surgical technique (PST) alone and with advanced platelet rich fibrin (A-PRF) in the management of bilateral multiple adjacent gingival recession defects (MAGRD).

METHODS

One hundred and sixty five MAGRD were randomly assigned to control group (treated with PST) and test group (PST with A-PRF). Clinical parameters of gingival recession depth (GRD), gingival recession width (GRW), width of keratinised gingiva (WKG), complete root coverage (CRC) and gingival thickness (GT) on ST-CBCT was measured at 2, 4 and 6 mm apically from the gingival margin. Also, root coverage aesthetic score and patient satisfaction ratings were recorded at baseline, 6 and 12 months postoperatively.

RESULTS

Substantial reduction in GRD (Test: 1.29 ± 0.69 mm and Control 0.98 ± 0.30 mm) (p < 0.001) and GRW (Test: 2.03 ± 0.90 mm and control 1.73 ± 0.99 mm) (p < 0.05) with associated gain in WKG and GT was observed (p < 0.001). Mean GT values were increased in both the groups at 2, 4 and 6 mm from the crest. Comparison of Test and Control groups yielded significant reductions in GRD (-0.17 ± 0.56 mm) and WKG (0.73 ± 1.07 mm) favoring the Test group (p < 0.05). Similar increase in GT was observed with better results in Test than control group. (p < 0.001).

CONCLUSION

Both groups exhibited sound clinical outcomes with test group offering better resolution of MAGRD in comparison to control group. Also, it enhances clinical and therapeutic end results in terms of attaining reduction in GRD and GRW along with greater gain in KTW and GT.

CLINICAL SIGNIFICANCE

PST as a minimally invasive approach has numerous benefits, some of which include the absence of scarring and improved aesthetics linked to faster wound healing. The addition of A-PRF enhances the intended therapy outcomes, which is beneficial for both patients and professionals in the field of periodontics.

Clinical and patient-reported outcomes of tissue engineering strategies for periodontal and peri-implant reconstruction

Scientific advancements in biomaterials, cellular therapies, and growth factors have brought new therapeutic options for periodontal and peri-implant reconstructive procedures. These tissue engineering strategies involve the enrichment of scaffolds with living cells or signaling molecules and aim at mimicking the cascades of wound healing events and the clinical outcomes of conventional autogenous grafts, without the need for donor tissue. Several tissue engineering strategies have been explored over the years for a variety of clinical scenarios, including periodontal regeneration, treatment of gingival recessions/mucogingival conditions, alveolar ridge preservation, bone augmentation procedures, sinus floor elevation, and peri-implant bone regeneration therapies. The goal of this article was to review the tissue engineering strategies that have been performed for periodontal and peri-implant reconstruction and implant site development, and to evaluate their safety, invasiveness, efficacy, and patient-reported outcomes. A detailed systematic search was conducted to identify eligible randomized controlled trials reporting the outcomes of tissue engineering strategies utilized for the aforementioned indications. A total of 128 trials were ultimately included in this review for a detailed qualitative analysis. Commonly performed tissue engineering strategies involved scaffolds enriched with mesenchymal or somatic cells (cell-based tissue engineering strategies), or more often scaffolds loaded with signaling molecules/growth factors (signaling molecule-based tissue engineering strategies). These approaches were found to be safe when utilized for periodontal and peri-implant reconstruction therapies and implant site development. Tissue engineering strategies demonstrated either similar or superior clinical outcomes than conventional approaches for the treatment of infrabony and furcation defects, alveolar ridge preservation, and sinus floor augmentation. Tissue engineering strategies can promote higher root coverage, keratinized tissue width, and gingival thickness gain than scaffolds alone can, and they can often obtain similar mean root coverage compared with autogenous grafts. There is some evidence suggesting that tissue engineering strategies can have a positive effect on patient morbidity, their preference, esthetics, and quality of life when utilized for the treatment of mucogingival deformities. Similarly, tissue engineering strategies can reduce the invasiveness and complications of autogenous graft-based staged bone augmentation. More studies incorporating patient-reported outcomes are needed to understand the cost-benefits of tissue engineering strategies compared with traditional treatments.

Efficacy of biologics in root coverage and gingival augmentation therapy: An American Academy of Periodontology best evidence systematic review and network meta-analysis

BACKGROUND

The aim of this systematic review was to assess the efficacy of three biologics, namely autologous blood-derived products (ABPs), enamel matrix derivatives (EMD) and recombinant human platelet-derived growth factor BB (rhPDGF-BB), in root coverage and gingival augmentation therapy.

METHODS

The protocol of this PRISMA 2020-compliant systematic review was registered in PROSPERO (CRD42021285917). After study selection, data of interest were extracted. A network meta-analysis (NMA) was conducted to assess the effect of different surgical interventions on the main clinical outcomes of interest (i.e., mean root coverage [MRC%], complete root coverage [CRC%], keratinized tissue width [KTW], gingival thickness [GT] change, and recession depth [RD] reduction).

RESULTS

A total of 48 trials reported in 55 articles were selected. All studies reported on the treatment of gingival recession defects for root coverage purposes. Forty-six treatment arms from 24 trials were included in the NMA. These arms consisted of treatment with coronally advanced flap (CAF) alone, EMD + CAF, platelet-rich fibrin (PRF) + CAF, and subepithelial connective tissue graft (SCTG) + CAF. Regarding MRC%, SCTG+CAF was associated with a significant higher estimate (13.41%, 95% CI [8.06-18.75], P <  0.01), while EMD+CAF (6.68%, 95% CI [-0.03 to 13.4], P = 0.061) and PRF+CAF (1.03%, 95% CI [-5.65 to 7.72], P = 0.71) failed to show statistically significant differences compared with CAF alone (control group) or with each other. Similarly, only SCTG+CAF led to a significantly higher CRC% (14.41%, 95% CI [4.21 to 24.61], P < 0.01), while treatment arms EMD + CAF (13.48%, 95% CI [-3.34 to 30.32], P = 0.11) and PRF+CAF (-0.91%, 95% CI [-15.38, 13.57], p = 0.81) did not show significant differences compared with CAF alone or with each other. Differences in the CI of PRF+CAF (symmetrical around a zero adjunctive effect) and EMD+CAF (non-symmetrical) suggest that EMD could have some additional value compared with PRF. Treatment with SCTG+CAF led to a statistically significant higher RD reduction (-0.39 mm, 95% CI [-0.55 to 0.22], P < 0.01), however EMD+CAF (-0.13 mm, 95% CI [-0.29 to 0.01], P = 0.08) and PRF+CAF (-0.06 mm, 95% CI [-0.23 to 0.09], P = 0.39) failed to show significant differences compared with CAF or with each other. While SCTG+CAF was associated with a statistically significant higher gain of KTW (0.71 mm, 95% CI [0.48 to 0.93], P < 0.01), EMD+CAF (0.24 mm, 95% CI [-0.02 to 0.51], P = 0.08) and PRF+CAF (0.08 mm, 95% CI [-0.23 to 0.41], P = 0.58) did not result into significant changes compared with CAF alone or with each other. Regarding the use of rhPDGF-BB+CAF, although available studies have reported equivalent results compared with SCTG+CAF, evidence is very limited.

CONCLUSIONS

The use of ABPs, EMD, or rhPDGF-BB in conjunction with a CAF for root coverage purposes is safe and generally promotes significant improvements respective to baseline clinical parameters. However, the adjunctive use of ABPs and EMD does not provide substantial additional improvements in terms of clinical outcomes and patient-reported outcome measures to those achieved using CAF alone, when baseline KTW is >2 mm. Both PRF+CAF and EMD+CAF rendered inferior MRC%, CRC%, RD reduction, and KTW gain compared with SCTG+CAF, which should still be considered the gold-standard in root coverage therapy. Although some studies have reported equivalent results for rhPDGF-BB+CAF compared with the gold-standard intervention, limited evidence precludes formal comparisons with CAF or SCTG+CAF that could be extrapolated to guide clinical practice.

Development and regeneration of periodontal supporting tissues

Periodontal tissues, including gingiva, cementum, periodontal ligament, and alveolar bone, play important roles in oral health. Under physiological conditions, periodontal tissues surround and support the teeth, maintaining the stability of the teeth and distributing the chewing forces. However, under pathological conditions, with the actions of various pathogenic factors, the periodontal tissues gradually undergo some irreversible changes, that is, gingival recession, periodontal ligament rupture, periodontal pocket formation, alveolar bone resorption, eventually leading to the loosening and even loss of the teeth. Currently, the regenerations of the periodontal tissues are still challenging. Therefore, it is necessary to study the development of the periodontal tissues, the principles and processes of which can be used to develop new strategies for the regeneration of periodontal tissues. This review summarizes the development of periodontal tissues and current strategies for periodontal healing and regeneration.

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.

Efficacy of a harvest graft substitute for recession coverage and soft tissue volume augmentation: A randomized controlled trial

BACKGROUND

The autogenous connective tissue graft (CTG) with coronally advanced flap (CTG+CAF) is the "gold standard" for recession defect coverage; however, researchers continue to pursue lower morbidity, more convenient and unlimited supply harvest graft substitutes, including those that could provide soft tissue volume augmentation.

METHODS

A randomized, controlled, double-masked comparison of a volume-stable collagen matrix (VCMX) versus CTG was conducted at four clinical investigation sites. Single, contralateral, within patient matched-pair, RT1 recession defects were treated with VCMX+CAF (test) and CTG+CAF (control). The primary efficacy end point was percent root coverage at 6 months. Secondary efficacy end points included clinical measures such as soft tissue volume, attachment level, and keratinized tissue width. Patient-reported outcomes included measures such as discomfort, esthetics, and overall satisfaction; 6-month end point results were followed for 1 year.

RESULTS

Thirty patients received control and test therapies, and all patients were available for follow-up measures. Average percent root coverage for CTG+CAF was 90.5% ± 14.87% versus 70.7% ± 28.26% for VCMX+CAF, P <0.0001. Both therapies produced significant soft tissue volume increases (84.8 ± 47.43 mm² control versus 48.90 ± 35.58 mm² test, P = 0.0006). The test, harvest graft substitute produced less postoperative pain and was preferred by patients at the 6-month end point. All other end point measures were not significantly different.

CONCLUSIONS

VCMX+CAF root coverage was inferior to CTG+CAF but produced less morbidity and was preferred by patients. Case/patient selection and surgical technique appear key to achieving successful results with the harvest graft alternative.

Root coverage stability: A systematic overview of controlled clinical trials with at least 5 years of follow-up

Objectives

To systematically assess the long‐term outcome (≥5 years) of root coverage procedures reported in controlled clinical trials.

Material and Methods

Literature search was performed according to the PRISMA guidelines with the following eligibility criteria: (a) English or German language; (b) controlled (CT) or randomised controlled clinical trials (RCT); (c) root coverage procedure with ≥5 years follow‐up; and (d) clinical treatment effect size and/or patient‐related outcome measures (PROMs) reported.

Results

Four CT and 14 RCT with a follow‐up of 5–20 years fulfilled the eligibility criteria; sample size per study ranged from 8 to 70 patients contributing with 18–149 sites. Coronally advanced flap (CAF) and CAF + connective tissue graft (CTG) were the prevalent treatments (i.e., in 24 and 38% of the groups, respectively), while other flap designs and adjuncts (i.e., enamel matrix derivative, bone graft, collagen membrane) were represented only once. For single Miller class I/II gingival recessions (GR), CAF + CTG appeared advantageous compared to other techniques, and provided low residual recession depths (i.e., ≤0.5 mm), and complete root coverage in ≥2/3 of the patients; similar tendency was observed for multiple GR. No data on Miller class III/IV GR is available. No meta‐analysis was feasible due to lack of similarity in the clinical and methodological characteristics across the trials and observed comparisons of interventions.

Conclusions

CAF + CTG appears to be the ‘gold standard’ technique for the treatment of single and multiple Miller class I/II GR also in regard to long‐term (i.e., ≥5 years of follow‐up) treatment outcomes. There is little information regarding the performance, on the long‐term, of other techniques and adjuncts.

Efficacy of recombinant human fibroblast growth factor 2 impregnated absorbable collagen membrane in the treatment of Miller's Class I and II gingival recession defects Preliminary results from the first in human clinical trial

Aims:

This study was a single-arm trial to obtain preliminary data on the efficacy of collagen membranes impregnated with recombinant human fibroblast growth factor-2 (rhFGF-2) in the treatment of Miller's Class I and II gingival recessions.

Materials and Methods:

Twenty-one individuals (34 sites) presenting with localized Miller's Class I and II gingival recessions were included in this study. Following a standard surgical protocol, rhFGF-2-impregnated membranes were placed in sites with gingival recession. Clinical parameters such as width of keratinized gingiva (wKG), recession depth (RD), and probing depth were measured at baseline and after therapy completion at 3 and 6 months.

Results:

Most of the sites exhibited favorable clinical healing; the most common complications were persistent edematous and inflamed gingivae beyond 1 week (n = 3), development of residual periodontal pockets (n = 2), and no reduction in RDs (n = 2). Significant improvements in wKG and RD were noted from baseline to 6 months.

Conclusion:

rhFGF-2-impregnated collagen membranes showed promising results in terms of increasing the wKG and recession coverage. A comparison with other standard therapies and agents in subsequent trials may shed more light on the clinical efficacy of this material.

An evidence-based system for the classification and clinical management of non-proximal gingival recession defects

Gingival recession defect (GRD) may be defined as an apical migration of the gingival margin respective to the cementoenamel junction resulting in partial exposure of the root surface to the oral cavity, which may have important esthetic, functional, and periodontal health implications. A novel system for the classification and management of non-proximal GRDs is proposed in this article. This evidence-based system consists of two essential components: (1) Establishment of the GRD type based on the midbuccal/midlingual attachment level respective to the interproximal bone level, and (2) Assessment of the gingival phenotype according to the width of attached gingiva and gingival thickness. Each category of this new classification system is linked with treatment recommendations substantiated by relevant literature pertaining to the outcomes of validated root coverage procedures in specific scenarios, which can be used as a guide for clinical decision-making in daily practice.

Recombinant Human Platelet-Derived Growth Factor: A Systematic Review of Clinical Findings in Oral Regenerative Procedures

AIM

The use of recombinant human platelet-derived growth factor-BB (rhPDGF) has received Food and Drug Administration approval for the treatment of periodontal and orthopedic bone defects and dermal wound healing. Many studies have investigated its regenerative potential in a variety of other oral clinical indications. The aim of this systematic review was to assess the efficacy, safety, and clinical benefit of recombinant human platelet-derived growth factor (rhPDGF) use for alveolar bone and/or soft tissue regeneration.

MATERIAL AND METHODS

Comprehensive electronic and manual literature searches according to the PRISMA guidelines were performed to identify interventional and observational studies evaluating the regenerative applications of rhPDGF-BB. The primary outcomes were the safety, efficacy, and overall clinical benefit of rhPDGF use in oral regenerative procedures.

RESULTS

Sixty-three human clinical studies (mean ± SD follow-up period of 10.7 ± 3.3 mo) were included in the qualitative analysis. No serious adverse effects were reported in any of the 63 studies, aside from the postoperative complications routinely associated with surgical therapy. Use of rhPDGF was shown to be beneficial when combined with allografts, xenografts, and alloplasts (the latter tricalcium phosphate [β-TCP]) for the treatment of periodontal defects and gingival recession. The use of rhPDGF also led to favorable clinical outcomes when combined with allografts or xenografts for guided bone regeneration (GBR) and alveolar ridge preservation. While favorable clinical results support the use of the combination of rhPDGF plus allograft or xenograft for GBR, ARP, and sinus floor augmentation, current data support the use of rhPDGF and alloplasts (e.g., β-TCP) only in periodontal defects and gingival recession.

CONCLUSIONS

Based on the clinical evidence, rhPDGF is safe and provides clinical benefits when used in combination with bone allografts, xenograft, or β-TCP for the treatment of intrabony and furcation periodontal defects and gingival recession or when used with allografts or xenograft for GBR and ARP (PROSPERO CRD42020142446).

KNOWLEDGE TRANSFER STATEMENT

Clinicians should be aware that rhPDGF is a safe and effective approach for the treatment of intrabony and furcation periodontal defects and gingival recession or when used with allografts or xenograft for bone regeneration and alveolar ridge preservation. With consideration of cost and patient preference, this result could lead to more appropriate therapeutic decisions.

Biologics-based regenerative technologies for periodontal soft tissue engineering

This manuscript provides a state-of-the-art review on the efficacy of biologics in root coverage procedures, including enamel matrix derivative, platelet-derived growth factor, platelet concentrates, and fibroblast-growth factor-2. The mechanism of action and the rationale for using biologics in periodontal plastic surgery, as well as their anticipated benefits when compared with conventional approaches are discussed. Although the clinical significance is still under investigation, preclinical data and histologic evidence demonstrate that biologic-based techniques are able to promote periodontal regeneration coupled with the provision of tooth root coverage.

Treatment of Recession Defects With Mucosal Access and Use of Soft Tissue Allograft: A Case Report of a Simplified Protocol

INTRODUCTION

Esthetic and functional root coverage procedures using a variety of techniques and materials allow for predictable outcomes in Miller Class I and II defects, but may be accompanied by high levels of postoperative discomfort and lengthy intrasurgical time. Current techniques may also require a steep practitioner learning curve, cumbersome intrasurgical steps, and their use in challenging clinical situations, e.g. multiple adjacent recession defects, limited vestibular depth, and anatomical limitations can prove difficult. This report introduces the side access mucosal releasing incision (SAMRI) technique as an innovative and simplified method to perform mucosal-access root coverage procedures.

CASE PRESENTATION

A 42-year-old female presents with 3 to 4 mm of gingival recession at #9-11 and opts for treatment with a vestibular approach and acellular dermal matrix graft to avoid a secondary surgical site.

CONCLUSION

SAMRI procedure allows for optimal root coverage and esthetic results while limiting intrasurgical time and postoperative patient morbidity.

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.

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.

Biodegradable gelatin/beta-tricalcium phosphate sponges incorporating recombinant human fibroblast growth factor-2 for treatment of recession-type defects: A split-mouth study in dogs

BACKGROUND AND OBJECTIVE

Tissue engineering by using recombinant human (rh) growth factor technology may offer a promising therapeutic approach for treatment of gingival recession. Fibroblast growth factor-2 (FGF-2) has shown the ability to promote periodontal regeneration. Gelatin/beta-tricalcium phosphate (gelatin/β-TCP) sponges have been developed to control the release of growth factors. The present study evaluated the periodontal regenerative efficacy of rhFGF-2 by comparing gelatin/β-TCP sponges incorporated with rhFGF-2 to the scaffolds alone in artificially created recession-type defects in dogs.

MATERIAL AND METHODS

Critically sized buccal gingival recession defects were surgically created on maxillary canine teeth of five dogs. In each animal, defects were randomized to receive either a gelatin/β-TCP sponge soaked with rhFGF-2 (gelatin/β-TCP/rhFGF-2) or phosphate-buffered saline (gelatin/β-TCP). Eight weeks after surgery, biopsy specimens were obtained and subjected to microcomputed tomography and histological analyses.

RESULTS

Complete root coverage was achieved in both groups. Microcomputed tomography revealed significantly greater new bone volume in the gelatin/β-TCP/rhFGF-2 group. Histologically, both groups achieved periodontal regeneration; however, gelatin/β-TCP/rhFGF-2 sites exhibited more tissue regeneration, characterized by significantly larger amounts of new cementum and new bone. Gelatin/β-TCP sites featured increased long junctional epithelium and connective tissue attachment. In the gelatin/β-TCP/rhFGF-2 sites, new bone exhibited many haversian canals and circumferential lamellae as well as remarkably thick periosteum with blood vascularization and hypercellularity.

CONCLUSION

Within the limitations of this study, rhFGF-2 in gelatin/β-TCP sponges exhibits an increased potential to support periodontal wound healing/regeneration in canine recession-type defects.

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).

Growth factors and beta-tricalcium phosphate in the treatment of periodontal intraosseous defects: A systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the effectiveness at different points in time, of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) coated onto a beta-tricalcium phosphate (β-TCP) carrier compared to β-TCP alone, or to recombinant human growth/differentiation factor-5 (rhGDF-5) adsorbed onto a β-TCP scaffold in intraosseous periodontal defects.

DESIGN

A digital search for randomised controlled trials (RCTs) was conducted on MEDLINE/PubMed. The quality of reporting and the risk of bias of the included RCTs were assessed using the CONSORT guidelines and the Cochrane risk of bias tool. The difference between the means of the outcomes at baseline and at follow-up for each group was tested using the Student's t-test for paired samples. The difference between the means of the outcome changes at follow-up between groups was analysed using the Student's t-test for two independent samples. Prior to each analysis a test of homogeneity of variances (Ansari-Bradley) was performed.

RESULTS

From 11 articles assessed for eligibility, 5 RCTs were included in this review. The risk of bias was considered to be low in 2 articles, medium in 1 study and high in 2 studies.

CONCLUSIONS

In the treatment of periodontal intraosseous defects the application of rhPDGF-BB/β-TCP improved all outcomes when compared to β-TCP at 6 months follow-up. Either rhPDGF-BB/β-TCP or rhGDF-5/β-TCP seemed to provide similar results in terms of probing pocket depth (PPD) reduction and clinical attachment level (CAL) gain. The application of rhGDF-5/β-TCP resulted in a more pronounced reduction in gingival recession (GR) depth at 6 months follow-up compared to rhPDGF-BB/β-TCP.

Non-Pedicled Buccal Fat Pad Grafts to Treatment for Class I and II Gingival Recessions: A Clinical Trial

The aim of this study was to analyze the transplant efficiency of non-pedicled buccal fat pad graft (BFPG) for the treatment of Miller Class I or II gingival recessions (GRs) and to compare these results with those of subepithelial connective tissue graft (SCTG), which is considered the gold standard. Twelve patients with Miller Class I or II (≥2 mm) bilateral recessions in maxillary premolars or canines were selected. Recessions were randomly assigned to receive SCTG or BFPG. The clinical parameters evaluated at baseline and at 1, 3, and 6 months postoperatively included gingival index, plaque index, probing depth, GR, clinical attachment level, width of keratinized tissue, thickness of keratinized tissue and gingival margin to the acrylic guide. None of the evaluated clinical parameters differed significantly between the groups. At all evaluated postoperative time-points, both groups exhibited statistically significant differences in GR and gingival margin to the acrylic guide compared to baseline. Six months after surgery, the mean percentages of root coverage were 67.5% and 87.5% in the BFPG and SCTG groups respectively. In both groups, complete root coverage was observed in 50% of cases 6 months after surgery. The results presented herein indicate that the use of BFPG transplant has clinical similarities with SCTG and both may be considered as clinically successful methods for treating Miller Class I and II GRs.

Biologic Agents for Periodontal Regeneration and Implant Site Development

The advancement of molecular mediators or biologic agents has increased tremendously during the last decade in periodontology and dental implantology. Implant site development and reconstruction of the lost periodontium represent main fields in which these molecular mediators have been employed and investigated. Different growth factors trigger different reactions in the tissues of the periodontium at various cellular levels. Proliferation, migration, and differentiation constitute the main target areas of these molecular mediators. It was the purpose of this comprehensive review to describe the origin and rationale, evidence, and the most current understanding of the following biologic agents: Recombinant Human Platelet-Derived Growth Factor-BB (rhPDGF-BB), Enamel Matrix Derivate (EMD), Platelet-Rich Plasma (PRP) and Platelet-Rich Fibrin (PRF), Recombinant Human Fibroblast Growth Factor-2 (rhFGF-2), Bone Morphogenic Proteins (BMPs, BMP-2 and BMP-7), Teriparatide PTH, and Growth Differential Factor-5 (GDF-5).

[Experimental study of the collagen matrix for increase the gums using a 3D-modeling]

In an experimental study on mini-pigs demonstrated that the use of collagen matrix Mucograft open method leads to the formation of mature connective tissue around the implants, more pronounced after 70 days, and the width of attached mucosa already 45th day (from 4.4 ± 0.3 to 7.7 ± 0.5 mm) is comparable to that of free gingival graft. Three-dimensional computer modeling of jaws experimental animals showed the soft tissue augmentation by 0.8 ± 0.1 cm3 after use of collagen matrix Mucograft and 1.1 ± 0.12 cm3 after free gingival graft.

Periodontal soft tissue root coverage procedures: a consensus report from the AAP Regeneration Workshop

BACKGROUND

Management of gingival recession defects, a common periodontal condition, using root coverage procedures is an important aspect of periodontal regenerative therapy. The goal of the periodontal soft tissue root coverage procedures group was to develop a consensus report based on the accompanying systematic review of root coverage procedures, including priorities for future research and identification of the best evidence available to manage different clinical scenarios.

METHODS

The group reviewed and discussed the accompanying systematic review, which covered treatment of single-tooth recession defects, multiple-tooth recession defects, and additional focused questions on relevant clinical topics. The consensus group members submitted additional material for consideration by the group in advance and at the time of the meeting. The group also identified priorities for future research.

RESULTS

All reviewed root coverage procedures provide significant reduction in recession depth, especially for Miller Class I and II recession defects. Subepithelial connective tissue graft (SCTG) procedures provide the best root coverage outcomes. Acellular dermal matrix graft (ADMG) or enamel matrix derivative (EMD) in conjunction with a coronally advanced flap (CAF) can serve as alternatives to autogenous donor tissue. Additional research is needed to do the following: 1) assess the treatment outcomes for multiple-tooth recession defects, oral sites other than maxillary canine and premolar teeth, and Miller Class III and IV defects; 2) assess the role of patient- and site-specific factors on procedure outcomes; and 3) obtain evidence on patient-reported outcomes.

CONCLUSIONS

Predictable root coverage is possible for single-tooth and multiple-tooth recession defects, with SCTG procedures providing the best root coverage outcomes. Alternatives to SCTG are supported by evidence of varying strength. Additional research is needed on treatment outcomes for specific oral sites. Clinical Recommendation: For Miller Class I and II single-tooth recession defects, SCTG procedures provide the best outcomes, whereas ADMG or EMD in conjunction with CAF may be used as an alternative.

Effect of platelet-derived growth factor-BB on tissue integration of cross-linked and non-cross-linked collagen matrices in a rat ectopic model

AIM

To test whether or not the network structure and the addition of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to a chemically cross-linked collagen matrix (CCM)- and a non-cross-linked collagen matrix (NCCM)-influenced tissue integration, angiogenesis, and matrix degradation.

MATERIALS AND METHODS

Four treatment modalities were randomly assigned to four unconnected pouches in the back of 50 rats: (i) CCM-S (soaked in saline), (ii) CCM-P (plus rhPDGF-BB), (iii) NCCM-S (soaked in saline), and (iv) NCCM-P (plus rhPDGF-BB). The animals were sacrificed at 2, 4, 8, 16, and 24 weeks. Descriptive histology and histomorphometric assessments were performed thereby evaluating matrix thickness, the number of vessels (angiogenesis), and connective tissue formation. Means and standard deviations were calculated. Robust linear mixed modeling was used to test the effect of group (NCCM vs CCM), rhPDGF-BB, and time point of sacrifice (2, 4, and 8 weeks).

RESULTS

The thickness of NCCM groups revealed stability (range 440-570 μm) over 8 weeks, while the matrices were no longer present at 16 and 24 weeks. CCM matrices demonstrated a maximal thickness at 2 weeks (2689 ± 187 μm for CCM-S and 2693 ± 389 μm for CCM-P), a decrease of roughly 40% at 8 weeks, but were still present at 16 and 24 weeks. Vascularization of NCCM gradually increased over time with a peak (mean 17.0; SD 1.7) for NCCM-S and NCCM-P (22.0 ± 34.8) at 8 weeks. Angiogenesis in CCM was significantly more pronounced at early time points with a peak at 2 weeks (29.3 ± 16.8 for CCM-S and 30.3 ± 18.4 for CCM-P). No statistically significant effect of rhPDGF-BB was observed for any of the evaluated parameters (all P > 0.05).

CONCLUSIONS

The compact layer (in NCCM) delayed angiogenesis and connective tissue formation, while the spongeous cross-linked matrix of CCM facilitated early vascularization and demonstrated network presence over a longer time span.