Significance of the Epithelial Collar on the Subepithelial Connective Tissue Graft

Long-term stability (21-30 years) of root coverage outcomes using sub-epithelial connective tissue grafts at single or multiple gingival recessions: A longitudinal case series

AIM

To evaluate outcomes and predictive factors for the long-term stability of root coverage using a sub-epithelial connective tissue graft.

MATERIALS AND METHODS

One-hundred and two healthy subjects (221 gingival recessions, GRs) were treated from 1987 to 1996. Keratinized tissue width (KTW), GR depth (RD), GR width (RW) and GR area (RA) were evaluated at baseline (M0) and at 1 month (M1), 1 year (M2), 11 years (M3), 21 years (M4) and 27 years (M5) after surgery. Primary outcomes consisted of complete root coverage (cRC) and relative dimensional changes in recession depth (measured in mm [c%-RD]), recession width (measured in mm [c%-RW]) and recession area (measured in mm2 [c%-RA]).

RESULTS

cRC was 88.7% at 1 year (M2), 59.8% at M3, 44.4% at M4 and 51.9% at M5. Average c%-RD was 95.2% at 1 year, 81.9% at M3, 71.5% at M4 and 81.7% at M5. KTW increased after surgery and over time and was positively correlated with favourable outcomes. Increased baseline RA was associated with less favourable clinical outcomes.

CONCLUSIONS

The sub-epithelial connective tissue graft is effective in the treatment of GRs and facilitates long-term stability of clinical outcomes. Wider baseline RA was a strong predictor of unfavourable short- and long-term RC outcomes.

Use of a hybrid soft tissue autograft for gingival phenotype modification lingual to mandibular incisors

Presence of adequate dimensions of keratinized/attached gingiva (KT/AG) and gingival thickness (GT) is considered necessary to maintain optimal periodontal health and long-term stability of gingival margin. Gingival phenotype modification therapies to increase these two dimensions (GT and KT/AG) on the buccal aspect of teeth have been widely reported, but the literature on lingual gingival augmentation is scarce. The purpose of this paper is to report the outcomes of a case treated with an envelope flap combined with a hybrid soft tissue autograft (subepithelial connective tissue graft with an epithelial collar) for phenotype modification of gingiva lingual to mandibular incisors presenting with thin gingiva (<1 mm) and lack of AG in tooth # 31 and 42. At 12 months follow-up, a substantial gain in KT, AG and GT along with partial root coverage was achieved.

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.

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.

Treatment of Multiple Adjacent Class I and Class II Gingival Recessions by Modified Microsurgical Tunnel Technique and Modified Coronally Advanced Flap Using Connective Tissue Graft: A Randomized Mono-center Clinical Trial

Background

Complete and uneventful recession coverage should be the aim of gingival recession treatment. Systematic reviews have said that coronally advanced flap with connective tissue graft (CTG) is the gold standard for gingival recession treatment. Minimally invasive procedures with optical magnification allow minimal tissue manipulation and precise adaptation of wound edges helping in faster and uneventful healing, thus bringing about a satisfactory clinical and patient outcome. Thus, the following study compares the clinical- and patient-related outcomes of modified microsurgical tunnel technique (MMTT) and modified coronally advanced flap (MCAF) using CTG in the coverage of multiple adjacent Miller's class I and II gingival recessions.

Materials and Methods

Gingival recession patients were selected and were assigned randomly to either MMTT+CTG or MCAF+CTG. Clinical parameters were evaluated at 1, 3, and 6 months. Patient's satisfaction level was assessed by measuring root coverage esthetic score, hypersensitivity, and morbidity. The statistical analysis was performed using commercially available software SPSS version 14. Descriptive statistics were expressed as mean±standard deviation for each parameter. Intragroup comparison was done by using the paired T-test. Intergroup comparison was done using the independent Student's T-test. The significance level was set at P = 0.05.

Results

MMTT+CTG showed a statistically significant greater clinical- and patient-related outcome.

Conclusion

MMTT+CTG, being a closed procedure, preserves the blood supply, helps in faster healing, and does not compromise the esthetics. All these lead to decreased morbidity and increased patient satisfaction which makes MMTT a superior technique than the conventional procedure in gingival recession treatment.

Partly deepithelialised palatal graft for the treatment of deep-wide palatal recession defect: simplified protocol with 18-month follow-up

Advances in periodontal plastic surgical procedures have led to achieve predictable root coverage outcomes for the recession defects. However, little has been reported and emphasised over management of palatal recession defects. The root coverage surgical procedures used for coverage of palatal recession defect are technically challenging in terms of accessibility and graft coverage. The purpose of this report is to describe a surgical technique used to manage deep-wide palatal recession defect. The technique uses partly deepithelialised palatal graft that is designed to approximately fit the defect site. This is employed for prolonged protection of the underlying healing process. This case report is unique in terms of treatment of deep (9.0 mm), wide (6.0 mm) palatal recession defect and its long-term follow-up for 18 months.

Gingival Thickness and Outcome of Periodontal Plastic Surgery Procedures: A Meta-regression Analysis

OBJECTIVE

To evaluate the impact of soft tissue thickness (STT) on root coverage achieved with different periodontal plastic surgery procedures.

BACKGROUND

Gingival recession has been managed successfully through various surgical approaches, with great variability in outcomes. Anatomic characteristics of the recipient site and selected technique account in part for this variability. Gingival flap thickness is one of the most critical site-related characteristics.

METHODS

An electronic search was conducted on the major databases (PubMed, Embase, Web of Science). Human prospective studies with at least 6 mo of follow-up and with a numeric baseline measurement for gingival thickness were eligible. Only studies including nonsmoking patients were considered. Variables included surgical approach, participant characteristics, local anatomic factors, and follow-up time. Primary outcome was mean percentage root coverage (%RC) achieved, and complete root coverage was a secondary outcome.

RESULTS

A total of 42 studies were included (35 randomized controlled trials, 5 case series, 1 prospective cohort study, and 1 controlled clinical trial). Across studies, the pooled %RC was 81.9% (95% CI, 79.1% to 84.7%). The %RC was not significantly associated (P = 0.267) with baseline soft tissue thickness; however there was a significant (P = 0.031) inverse relationship between STT and %RC after 12-mo follow-up. Subgroup analysis showed that for no graft, there was a significant (P = 0.025) positive relationship between STT and %RC with the exclusion of the single outlier study based on STT.

CONCLUSIONS

STT plays a limited role in predicting root coverage across all approaches; when flaps are performed with no graft, the effect of STT is most critical. The length of time following surgery appears to influence outcomes, with 12-mo follow-up offering greater insight.

KNOWLEDGE TRANSFER STATEMENT

The results of this study can suggest to clinicians which periodontal plastic surgery technique to employ when treating challenging cases. In particular, it can be helpful when selecting the treatment approach to treat thin phenotype sites. This study could help clinicians provide a more appropriate treatment decision in such cases.

44-year journey of palatal connective tissue graft harvest: A narrative review

Connective tissue graft (CTG) is considered the gold standard for soft-tissue correction and augmentation surgeries, but involves a secondary donor area and its associated complications. The techniques to harvest CTG have undergone a large number of modifications over a period of 44 years since the time it was introduced by Edel in 1974 to increase the width of keratinized gingiva. This review compiles all the techniques of graft harvest from the palate and their modifications which have been introduced in the last 44 years till date. This review is based on systematic reviews, comparative human studies, and case reports describing any new technique of graft harvest. Publications till April 2018 were selected and further reviewed. In addition, specific related journals and books were searched upon. In order to minimize the pain, bleeding, and morbidity associated with donor site, several researchers proposed harvesting of the connective tissue by means of different techniques, each precisely different from others in terms of design, incisions, and procedure of harvest. Although the latest techniques are minimally invasive with reduced incision lines, less compromised blood supply, accelerated healing, and no sloughing of the overlying flap, they are technique sensitive which requires higher expertise to execute.

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.

Sub-epithelial connective tissue graft for the management of Miller's class I and class II isolated gingival recession defect: A systematic review of the factors influencing the outcome

The aim of the present systematic review was to analyze the factors that affect the outcome of subepithelial connective tissue graft (SCTG) for managing Miller's class I and class II isolated gingival recession defect. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic reviews were used. Quality assessments of selected articles were performed. Data on root surface condition, recession type defect, flap thickness, different flap designs, different harvesting techniques, presence/absence of the epithelial collar, graft thickness, flap tension, suturing techniques, and smoking-related outcomes on root coverage were assessed. The SCTG procedure provides the best root coverage outcomes for Miller's class I and class II recession. The critical threshold of flap thickness was found to be 1 mm. Maximum root coverage was achieved by envelope and modified tunnel technique. SCTG with the epithelial collar does not provide additional gains than SCTG without the epithelial collar. The thickness of SCTG for root coverage was found to be 1.5-2 mm. Greater flap tension and smoking adversely affect root coverage outcomes. Analysis of the factors discussed would be of key importance for technique selection, and a combined approach involving factors favoring outcomes of SCTG could be of clinical relevance in recession coverage.

Periodontal soft tissue root coverage procedures: a systematic review from the AAP Regeneration Workshop

BACKGROUND

This paper aims to create a "bridge" between research and practice by developing a practical, extensive, and clinically relevant study that translates evidence-based findings on soft tissue root coverage (RC) of recession-type defects to daily clinical practice.

METHODS

This review is prepared in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement based on the proposed focused questions. A literature search with no restrictions regarding status or the language of publication was performed for MEDLINE and EMBASE databases up to and including June 2013. Systematic reviews (SRs), randomized clinical trials, controlled clinical trials, case series, and case reports evaluating recession areas that were treated by means of RC procedures were considered eligible for inclusion through the three parts of the study (part I, an overview of the base of SRs; part II, an alternative random-effects meta-analyses on mean percentage of RC and sites exhibiting complete RC; and part III, an SR of non-randomized trials exploring other conditions not extensively evaluated by previous SRs). Data on Class I, II, III, and IV recessions, type of histologic attachment achieved with treatment, recipient- and donor-site anatomic characteristics, smoking-related outcomes, root surface conditions, tooth type and location, long-term effectiveness outcomes, unusual conditions that may be reported during conventional daily practice, and patient-centered outcomes were assessed as well.

RESULTS

Of the 2,456 potentially eligible trials, 234 were included. Data on Class I, II, III, and IV gingival recessions, histologic attachment achieved after treatment, recipient- and donor-site anatomic characteristics, smoking-related outcomes, root surface conditions/biomodification, tooth type and location, long-term effectiveness outcomes and unusual conditions that may be reported during conventional daily practice, and patient-centered outcomes (i.e., esthetic, visual analog scale, complications, hypersensitivity, patients perceptions) were assessed. Subepithelial connective tissue (CT)-based procedures and coronally advanced flap plus acellular dermal matrix grafts, enamel matrix derivative, or collagen matrix led to the best improvements of recession depth, clinical attachment level (CAL) gain, and keratinized tissue (KT). Some conditions, such as smoking and use of magnification, may affect RC outcomes.

CONCLUSIONS

All RC procedures can provide significant reduction in recession depth and CAL gain for Miller Class I and II recession-type defects. Subepithelial CT graft-based procedures provided the best outcomes for clinical practice because of their superior percentages of mean and complete RC, as well as significant increase of KT.

Implant associated soft tissue defects in the anterior maxilla: a randomized control trial comparing subepithelial connective tissue graft and acellular dermal matrix allograft

INTRODUCTION

This randomized controlled clinical pilot trial compared the efficacy of 2 soft tissue grafting methods for correcting esthetic discrepancies associated with definitively restored implant crowns.

METHODS

Thirteen patients presenting with implants displaying recession, thin biotype, concavity defects, or a combination thereof associated with single crowned dental implants randomly received subepithelial connective tissue grafts (SCTG) in the control group (N = 7) or acellular dermal matrix (ADM) allografts in the test group (N = 6), both under coronally positioned flaps. Data regarding soft tissue, hard tissue, esthetics, and quality of life (QoL) parameters were collected over 6 months.

RESULTS

Both groups gained tissue thickness (SCTG: 63% and ADM: 105%), reduced concavity measures (SCTG: 82% and ADM: 96%), and improved recessions (SCTG: 40% and ADM: 28%) from baseline to 6 months. Clinicians determined improvement in esthetics for both groups (P = 0.001), unlike patients who did not change their esthetic ratings. No statistical differences were noted for QoL assessment; however, ADM subjects had more eventful wound healing (P = 0.021).

CONCLUSIONS

Within the limitations of this study, both SCTG and ADM result in increased mucosal thickness, reduction in concavity dimensions, and have a potential for recession reduction on definitively restored dental implants.

Histological assessment of the palatal mucosa and greater palatine artery with reference to subepithelial connective tissue grafting

This study aimed to measure the thickness of the epithelium and lamina propria of the palatal mucosa and to elucidate the location of the greater palatine artery to provide the anatomical basis for subepithelial connective tissue grafting. Thirty-two maxillary specimens, taken from the canine distal area to the first molar distal area, were embedded in paraffin and stained with hematoxylin-eosin. The thickness of the epithelium and lamina propria of the palatal mucosa was measured at three positions on these specimens, starting from 3 mm below the alveolar crest and in 3-mm intervals. The location of the greater palatine artery was evaluated by using image-processing software. The mean epithelial thickness decreased significantly in the posterior teeth; it was 0.41, 0.36, 0.32, and 0.30 mm in the canine, first premolar, second premolar, and first molar distal areas, respectively. The lamina propria was significantly thicker in the canine distal; it was 1.36, 1.08, 1.09, and 1.05 mm, respectively. The mean length from the alveolar crest to the greater palatine artery increased toward the posterior molar; it was 7.76, 9.21, 10.93, and 11.28 mm, respectively. The mean depth from the surface of the palatal mucosa to the greater palatine artery decreased from the canine distal to the first premolar distal but increased again toward the posterior molar; it was 3.97, 3.09, 3.58, and 5.50 mm, respectively. Detailed histological assessments of the lamina propria of the palatal mucosa and the greater palatine artery are expected to provide useful anatomical guidelines for subepithelial connective tissue grafting.

Treatment of localized gingival recessions using gingival unit grafts: a randomized controlled clinical trial

BACKGROUND

One of the success factors in periodontal plastic surgery is the synergistic relationship between involved tissues and vascular supply. Gingiva as a functional unit is unique with a specific vascular configuration and contains the supracrestal portion naturally created to survive over avascular root surfaces. The aim of this randomized controlled trial is to clinically evaluate the treatment of localized gingival recessions by using gingival unit grafts (palatal tissue involving marginal gingiva and papillae) compared with conventional palatal grafts.

METHODS

Seventeen patients with Class I to II recession defects on mandibular anterior teeth were included and randomly divided into two groups. Recessions were treated with gingival unit grafts in group 1 (n = 8) and with palatal grafts in group 2 (n = 9). Clinical parameters including vertical recession (VR), probing depth, keratinized tissue (KT), and attachment level were recorded at baseline and 8 months after surgery.

RESULTS

Both treatments produced significant clinical improvements within the groups. Intergroup comparison revealed significantly higher VR reduction, attachment, and KT gain in group 1 than in group 2; mean percentages of the defect coverage were 91.62% ± 9.74% and 68.97% ± 13.67%, respectively (P <0.05). Healing of the gingival unit donor site was uneventful.

CONCLUSION

Within its limits, this study demonstrates the possibility of treating buccal recessions with gingival unit grafts as an alternative technique using gingival donor graft of site-specific vascular configuration, with better defect coverage, clinical, and esthetic improvements compared with palatal grafts.