Evaluation of Human Recession Defects Treated with Coronally Advanced Flaps and Either Enamel Matrix Derivative or Connective Tissue. Part 2: Histological Evaluation

Tunnel technique and subepithelial connective tissue graft, with or without cross-linked hyaluronic acid, in the treatment of multiple gingival recessions: 12-month outcomes of a randomized clinical trial

BACKGROUND

This study evaluated the influence of the adjunctive application of a cross-linked hyaluronic acid (HA) in the treatment of multiple gingival recessions, using a modified coronally advanced tunnel (MCAT) technique and subepithelial connective tissue graft (SCTG) (MCAT+SCTG±HA).

METHODS

A randomized, split-mouth, double-masked comparison of the effects of MCAT+HA+SCTG (test) versus MCAT+SCTG (control) in the treatment of multiple, contralateral gingival recessions with clinical, esthetic, and histological evaluations was carried out. All samples were stained with hematoxylin and eosin, Masson's trichrome, Verhoeff-Van Gieson, and Alcian blue stain for semiquantitative evaluation. The primary outcome variable was 12-month mean root coverage (MRC).

RESULTS

Twenty-four patients with 266 gingival recessions received both control and test treatments (133 recessions per group). 12-month MRC of the MCAT+HA+SCTG group was not significantly different from the MCAT+SCTG group with 84.32%±  34.46% and 85.71%±  36.43%, respectively (p = 0.991). Both treatment modes produced favorable esthetic outcomes (root coverage esthetic score [RES] 9.51±  1.01 tests vs. 9.26±  1.10 controls, p = 0.7292). However, the application of HA improved soft tissue texture (p = 0.0091). The remaining end point measures did not differ significantly between groups. Histological evaluation showed a significantly greater number of elastic fibers and a moderate increase in collagen fiber density in biopsy samples taken from the test sides when compared to the control sides (p = 0.0419 and p = 0.300, respectively).

CONCLUSIONS

MCAT+SCTG is an effective procedure in the treatment of multiple recession Type 1 (RT1) and RT2 recessions. There were no statistically significant differences in evaluated clinical treatment outcomes in the MCAT+HA+SCTG group compared to the MCAT+SCTG group within a period of 12 months. The application of HA increased collagen and elastic fiber density.

Histological evaluation following treatment of recession-type defects with coronally advanced flap and a novel human recombinant amelogenin

OBJECTIVES

To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects.

MATERIALS AND METHODS

A total of 17 gingival recession-type defects were surgically created in the maxilla of three minipigs. The defects were randomly treated with a coronally advanced flap (CAF) and either rAmelX (test), or a CAF and placebo (control). At three months following reconstructive surgery, the animals were euthanized, and the healing outcomes histologically evaluated.

RESULTS

The test group yielded statistically significantly (p = 0.047) greater formation of cementum with inserting collagen fibers compared with the control group (i.e., 4.38 mm ± 0.36 mm vs. 3.48 mm ± 1.13 mm). Bone formation measured 2.15 mm ± 0.8 mm in the test group and 2.24 mm ± 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94).

CONCLUSIONS

The present data have provided for the first-time evidence for the potential of rAmelX to promote regeneration of periodontal ligament and root cementum in recession-type defects, thus warranting further preclinical and clinical testing.

CLINICAL RELEVANCE

The present results set the basis for the potential clinical application of rAmelX in reconstructive periodontal surgery.

Influence of Occlusal Hypofunction on Alveolar Bone Healing in Rats

The aim of this in vivo study was to investigate the effect of occlusal hypofunction on alveolar bone healing in the absence or presence of an enamel matrix derivative (EMD). A standardized fenestration defect over the root of the mandibular first molar in 15 Wistar rats was created. Occlusal hypofunction was induced by extraction of the antagonist. Regenerative therapy was performed by applying EMD to the fenestration defect. The following three groups were established: (a) normal occlusion without EMD treatment, (b) occlusal hypofunction without EMD treatment, and (c) occlusal hypofunction with EMD treatment. After four weeks, all animals were sacrificed, and histological (hematoxylin and eosin, tartrate-resistant acid phosphatase) as well as immunohistochemical analyses (periostin, osteopontin, osteocalcin) were performed. The occlusal hypofunction group showed delayed bone regeneration compared to the group with normal occlusion. The application of EMD could partially, but not completely, compensate for the inhibitory effects of occlusal hypofunction on bone healing, as evidenced by hematoxylin and eosin and immunohistochemistry for the aforementioned molecules. Our results suggest that normal occlusal loading, but not occlusal hypofunction, is beneficial to alveolar bone healing. Adequate occlusal loading appears to be as advantageous for alveolar bone healing as the regenerative potential of EMD.

The treatment of multiple gingival recession defects with connective tissue grafting and enamel matrix derivative in a private practice setting: Two case reports

BACKGROUND

Dentofacial esthetics has become a mainstay treatment in periodontics. For a periodontal private practice to succeed in a referral-based environment, predictability and stability in treatment results are crucial. The scientific literature provides a guide to successfully treating multiple recession defects with non-carious cervical lesions and lingual recession. These case reports show how the use of biologic mediators, proper case selection, and proper surgical technique may provide a better treatment outcome for our patients.

METHODS

Two patients with multiple gingival recession defects were treated with autogenous tissue grafting in conjunction with the application of enamel matrix derivative (EMD) to attempt root coverage. Based on the Cairo classification, the recession defects were classified as type I in the maxillary buccal and lingual recession in the mandibular anterior. There were areas of no attached gingiva, loss of enamel, and the presence of non-carious cervical lesions.

RESULTS

At 3-month post-treatment in case #1 and 6-month post-treatment in case #2, satisfactory esthetic results for the patients and clinician were achieved. These short-term follow-ups were favorable for root coverage and soft tissue healing, especially at the 1-week visit. There was noticeably less edema and erythema. Additionally, dental hypersensitivity was no longer reported for both patients.

CONCLUSION

By using biologic mediators, such as an EMD combined with connective tissue grafting, both multiple recession defects with non-carious cervical lesions, and lingual recession cases, can be treated successfully in a private practice setting. Using an EMD provides no additional risks to patients, may result in faster healing, and would afford stability of long-term success by influencing true periodontal regeneration.

Effect of Root Surface Biomodification on Multiple Recession Coverage with Modified Coronally Advanced Tunnel Technique and Subepithelial Connective Tissue Graft: A Retrospective Analysis

To improve treatment efficacy of gingival recessions (GR), chemical preparation of the exposed root surface was advocated. The aim of this study was to compare the additional influence of root biomodifications with 24% ethylenediaminetetraacetic acid (EDTA) alone or with enamel matrix derivative (EMD) on the 12 month outcomes of modified coronally advanced tunnel (MCAT) with subepithelial connective tissue graft in the treatment of multiple GR. Average root coverage (ARC), complete root coverage (CRC), reduction in GR, reduction in recession width (RW), gain in clinical attachment level (CAL), increase in gingival thickness (GT), increase in keratinized tissue width (KTW) and changes in root coverage esthetic score (RES) were evaluated. A total of 60 patients with 215 GR were enrolled. In 70, GR root surfaces were treated with EDTA + EMD, in other 72, with EDTA, while in the remaining 73 saline solution was applied. ARC was 94%, 89%, and 91% in the EDTA + EMD, the EDTA and the saline groups, respectively (p = 0.8871). Gains in clinical attachment level (CAL; 2.1 ± 1.1 mm) and RES values (9.6 ± 0.9) were significantly higher in the EDTA + EMD group, when compared with two other groups. The differences between other preoperative and postoperative parameters showed statistical significance only within but not between groups. MCAT outcomes may benefit from adjunctive use of EDTA + EMD regarding 12 month CAL gain and professionally assessed esthetics using RES following treatment of GR.

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.

Effects of Obesity on Bone Healing in Rats

Although the association between periodontitis and obesity is well explored, it is unclear whether obesity is associated with a worse therapeutic outcome after periodontal treatment. The aim of this study was to investigate the effects of obesity on bone healing with and without the application of regeneration-promoting molecules. A standardized bone fenestration-type defect was created over the root of the mandibular first molar in 15 Wistar rats. Ten animals received a high-fat, high-sucrose diet (HFSD), while the remaining five animals were fed a standard diet. During surgery, the fenestration defects from half of the HFSD-fed, i.e., obese animals, were treated with regeneration-promoting molecules (enamel matrix derivative; EMD). After four weeks, bone healing was evaluated by histomorphometry, TRAP staining and immunohistochemistry for RUNX2 and osteopontin. The analyses revealed that the spontaneous healing of the periodontal defects was compromised by obesity. Application of EMD partially compensated for the negative effect of obesity. Nevertheless, EMD-stimulated bone healing in obese animals was not better than the spontaneous healing in the obesity-free control group, indicating that obesity may also inhibit the stimulatory effects of regeneration-promoting molecules. Our results show that obesity can negatively influence bone healing and suggest that bone healing may be compromised in humans.

Soft Tissue Regeneration at Natural Teeth

This article provides an overview of the best-documented surgical techniques for recession coverage and draws conclusions for the clinician. Use of a connective tissue graft with either coronally advanced flap (CAF) or tunnel is the most predictable technique for the treatment of single and multiple gingival recessions. Long-term results exist only for CAF with/without connective tissue graft providing evidence for long-term stability with only minor relapses. Soft tissue replacement materials and biologics may represent a valuable modality to additionally improve the clinical outcomes obtained with CAF alone or, in certain clinical situations, to serve as an alternative to autogenous tissue.

Platelet-rich fibrin for root coverage: A plausible approach in periodontal plastic and esthetic surgery

Predictable esthetic root coverage has evolved into conventional treatment modalities making cosmetic procedures an integral part of periodontal treatment. The advent of second-generation platelet concentrates, i.e., platelet-rich fibrin (PRF), has broad clinical application in medical as well as dental field with its recent use for recession defects. The simplicity of PRF procurement and its low cost makes it most suitable for use in daily clinical practice. This particular case report foregrounds the benefit of PRF membrane along with coronally repositioned flap for mucogingival surgery on the labial surface of an upper anterior tooth.

Regenerative Potential of Enamel Matrix Protein Derivative and Acellular Dermal Matrix for Gingival Recession: A Systematic Review and Meta-Analysis

Objective: The purpose of this study was to assess the clinical effectiveness of using a combination of enamel matrix protein derivative and acellular dermal matrix in comparison to acellular dermal matrix alone for treating gingival recessions. Methods: The Cochrane Library (Wiley), PubMed by Medline (NLM), Medline (EBSCO), and Embase (Ovid) databases were searched for entries up to April 2020. Only clinical trials were included. Primary outcomes were root coverage (%), changes in keratinized tissue width and recession (mm). Meta-analysis was conducted for root coverage, changes in keratinized tissue width, recession, clinical attachment level and probing depth. Results: Four studies were selected for the analysis. In primary outcomes, root coverage, change in keratinized tissue width and recession analysis showed a mean difference of 4.99% (p = 0.11), 0.20 mm (p = 0.14) and 0.13 mm (p = 0.23) respectively between the two groups. Secondary outcomes analysis also exhibited a statistically insignificant difference between the test and control group with mean difference of 0.11 mm (p = 0.32) in clinical attachment level gain and -0.03 mm (p = 0.29) in probing depth reduction analysis. Conclusions: Within the limits of this study, enamel matrix protein derivative combined with acellular dermal matrix used for treating gingival recession defects resulted in no beneficial effect clinically than acellular dermal matrix only.

Does enamel matrix derivative application provide additional clinical benefits in the treatment of maxillary Miller class I and II gingival recession? A systematic review and meta-analysis

OBJECTIVE

This review aimed to evaluate the effects of enamel matrix derivative (EMD) in association with coronally advanced flap (CAF) or CAF + connective tissue graft (CTG) when compared with CAF alone or CAF + CTG for the treatment of gingival recessions (GR) in maxillary teeth.

METHODS

Five databases and gray literature were searched up to April 2020, to find randomized clinical trials comparing the clinical effects of CAF + EMD versus CAF alone (first group) or CAF + CTG + EMD versus CAF + CTG (second group) in the treatment of Miller class I and II or Cairo type I gingival recessions (GR). Random effects model of mean differences was used to determine the GR reduction, gain in keratinized tissue width (KTW), and gain in clinical attachment level (CAL). The trial sequential analysis (TSA) was implemented to determine the optimal information size (OIS) and imprecision using the GRADE approach. Bayes factors were calculated as complementary statistical evidence of p value.

RESULTS

From 1349 titles identified, 9 trials representing 336 GR were included. The meta-analysis showed a statistically significant difference for GR reduction and CAL gain in favor CAF + EMD (p ≤ 0.05). The additional effect of EMD showed a statistically significant difference in GR reduction in favor CAF + CTG + EMD (p ≤ 0.05). The differences in KTW gain proved to be not statistically significant in both comparison groups. The OIS were not met among meta-analyses. Evidence certainty according the GRADE approach proved to be moderate for GR reduction and gain in CAL, but very low for gain in KTW.

CONCLUSION

The adjunctive application of EMD in the treatment of GR in maxillary teeth either with CAF or CTG provided moderate certainty evidence in favor of their use for reduction in GR and gain in CAL at 6 and 12 months. However, their effect on the increase in keratinized tissue band height showed very low evidence certainty for its use.

CLINICAL RELEVANCE

To know if EMD could improve the results for root coverage.

Tunnel technique with enamel matrix derivative in addition to subepithelial connective tissue graft compared with connective tissue graft alone for the treatment of multiple gingival recessions: a randomized clinical trial

Objectives

The aim of this study was to compare outcomes of the modified coronally advanced tunnel technique (MCAT) combined with subepithelial connective tissue graft (SCTG) with or without enamel matrix derivative (EMD), in the treatment of gingival recession types 1 and 2.

Materials and methods

A total of 20 patients with 150 multiple gingival recessions (GR) were included in the study. On one side, MCAT was combined with SCTG and EMD (tests), whereas MCAT with SCTG was applied on the contralateral side (controls). Clinical parameters were measured at baseline and 6 months after surgery. Visual analog scales (VAS) and questionnaires were used to assess patient-reported outcomes and the root coverage esthetic score (RES) for professional esthetic evaluation.

Results

MCAT+SCTG+EMD was not superior with regard to root coverage. At 6 months, average root coverage (ARC) was 87.4% for SCTG+EMD-treated and 90.9% for SCTG-treated defects (p = 0.4170). Complete root coverage (CRC) was observed in 86.7% (tests) and 85.3% (controls) of the cases (p = 0.9872). Significantly less pain was reported using VAS (p = 0.0342) post-operatively in the SCTG+EMD group. Professional assessment of esthetic outcomes using RES showed a significant difference (9.25 versus 8.71, p = 0.0103) in favor of the test group.

Conclusions

Both treatment modalities were equally effective in treatment of multiple GR and led to similar improvements in clinical parameters. However, the application of EMD as an adjunct resulted in less post-operative pain and better professionally assessed esthetic outcomes.

Clinical relevance

Patients’ early morbidity and 6-month esthetic outcomes following GR coverage with MCAT might be influenced by means of EMD utilization.

A 3-year prospective clinical and patient-centered trial on subepithelial connective tissue graft with or without enamel matrix derivative in Class I-II Miller recessions

BACKGROUND AND OBJECTIVE

The study compared clinical and patient-centered outcomes of subepithelial connective tissue graft (CTG) with and without enamel matrix derivative (EMD) in the treatment of Class I-II Miller periodontal recession defects.

MATERIAL AND METHODS

This prospective clinical study evaluated 80 patients over a 3 years follow-up in a private periodontal practice. A total of 144 maxillary and mandibular anterior teeth were divided into two groups: group 1 (CTG with EMD-80 teeth) and group 2 (CTG only-64 teeth). Recession (REC), keratinized tissue (KT) width, % root overage, patient-centered outcomes, and pain visual analog scale (P-VAS) were compared between the two groups.

RESULTS

At 3 years follow-up at a patient level, statistically significant changes in REC were achieved in both group 1 (4.65 ± 1.84 to 0.39 ± 0.19 mm) and group 2 (4.43 ± 1.11 to 0.92 ± 0.43 mm). Complete root coverage (CRC) was achieved in 66.4% of group 1 and 50.1% of group 2. At both patient and tooth level, the 3-year outcomes were superior for group 1 compared with group 2 in terms of % root coverage, REC, and KT width. Clinical attachment loss (CAL) was reduced in group 1 compared with group 2 at the tooth level analysis only (<.01). Significantly less pain was reported using the pain visual analog Scale (P < .001) at the two weeks follow-up post-surgery in group 1.

CONCLUSIONS

Addition of EMD results in improved root coverage outcomes and higher amounts of keratinized tissue width 36 months after treatment of multiple adjacent recessions on maxillary and mandibular anterior teeth. The adjunctive use of EMD also resulted in significantly reduced pain 14 days after the surgery.

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.

The Additional Effect of Autologous Platelet Concentrates to Coronally Advanced Flap in the Treatment of Gingival Recessions: A Systematic Review and Meta-Analysis

Background

To improve the efficacy of regenerative treatment for gingival recessions, the autologous platelet concentrates (APCs) combined with coronally advanced flap (CAF) have been investigated. However, few studies systematically assess the complementary effect of APCs in periodontal regeneration. The present study aims to evaluate the additional effect of different types of APCs to CAF in the treatment of gingival recessions.

Methods

Electronic databases (EMBASE, MEDLINE, and Cochrane Central Register of Controlled Trails) and relevant journals were searched until May 15, 2019. Only randomized controlled trials (RCTs) in English were included. Outcome variables include root coverage (RC), recession depth (RD), clinical attachment level (CAL), keratinized tissue width (KTW), and gingival thickness (GT). Data were analyzed with Revman5.3. The estimate of effect sizes was expressed as the mean differences and the 95% confidence interval.

Results

8 RCTs involving 170 patients (328 sites) were included. Our meta-analysis indicated RC, RD, CAL, KTW, and GT were better improved in the CAF plus APCs groups than the CAF alone. The subgroup analyses revealed that platelet-rich fibrin (PRF) brought significant improvement in RC, RD, CAL, and GT. Concentrated growth factors (CGF) lead clinic beneficial in CAL, KTW, and GT. No significant effect of platelet-rich plasma (PRP) could be found in any clinical parameters when combined with CAF.

Conclusions

PRF could exert additional effect to CAF; the preferred treatment for gingival recessions was considered. Based on the limited studies, it seemed that PRP failed to show any additional effect and it was not suggested for gingival recessions. Given the limited research and high risk of bias, it is still needed to confirm the additional effect of CGF by more high-quality studies.

Split-mouth evaluation of connective tissue graft with or without enamel matrix derivative for the treatment of isolated gingival recession defects in dogs

OBJECTIVES

The potential additive effect of an enamel matrix derivative (EMD) to a subepithelial connective tissue graft (CTG) for recession coverage is still controversially discussed. Therefore, the aim of this study was to histologically evaluate the healing of gingival recessions treated with coronally advanced flap (CAF) and CTG with or without EMD in dogs.

MATERIALS AND METHODS

Gingival recession defects (5 mm wide and 7 mm deep) were surgically created on the labial side of bilateral maxillary canines in 7 dogs. After 8 weeks of plaque accumulation and subsequent 2 weeks of chemical plaque control, the 14 chronic defects were randomized to receive either CAF with CTG (CAF/CTG) or CAF with CTG and EMD (CAF/CTG/EMD). The animals were sacrificed 10 weeks after reconstructive surgery for histologic evaluation.

RESULTS

Treatment with CAF/CTG/EMD demonstrated statistically significantly better results in terms of probing pocket depth reduction (P < 0.05) and clinical attachment level gain (P < 0.001). The length of the epithelium was statistically significantly shorter in the CAF/CTG/EMD group than in the CAF/CTG group (1.00 ± 0.75 mm vs. 2.38 ± 1.48 mm, respectively, P < 0.01). Cementum formation was statistically significantly greater in the CAF/CTG/EMD group than following treatment with the CAF/CTG group (3.20 ± 0.89 mm vs. 1.88 ± 1.58 mm, respectively, P < 0.01). The CAF/CTG/EMD group showed statistically significantly greater complete periodontal regeneration (i.e., new cementum, new periodontal ligament, and new bone) than treatment with CAF/CTG (0.54 ± 0.73 mm vs. 0.07 ± 0.27 mm, respectively, P < 0.05).

CONCLUSION

Within their limits, the present findings indicate that the additional use of EMD in conjunction with CAF + CTG favors periodontal regeneration in gingival recession defects.

CLINICAL RELEVANCE

The present findings support the use of EMD combined with CTG and CAF for promoting periodontal regeneration in isolated gingival recession defects.

Exploring the Gingival Recession Surgical Treatment Modalities: A Literature Review

Gingival recessions present complex soft tissue pathology, with a multiple aetiology and a high prevalence which increases with age. They are defined as an exposure of the root surface of the teeth as a result of the apical migration of the gingival margin beyond the cementum-enamel junction, causing functional and aesthetic disturbances to the affected individuals. Aiming to ensure complete root coverage and satisfying aesthetic outcomes, a wide range of surgical techniques have been proposed through the decades for the treatment of the gingival recessions. The following literature review attempts to provide a comprehensive, structured and up-to-date summary of the relevant literature regarding these surgical techniques, aiming to emphasise for each technique its indications, its long-term success and predictability, its advantages and disadvantages about each other.

[The applications of periodontal gingival surgery. Ⅱ: alternative materials]

The main purposes of periodontal graft surgery include achieving root coverage, improving the clinical attachment level and keratinized tissue, and advancing the procedure of periodontal plastic surgery. Autogenous graft, such as subepithelial connective tissue graft-based procedure, provide the best outcomes for mean and complete root coverage, as well as increase in keratinized tissue. However, a disadvantage of the procedure is in the location of the operation itself: the additional surgical site (palate). Therefore, clinicians are always looking for graft substitutes. This article will discuss the evidence supporting the use of 1) acellular dermal matrix (ADM); 2) xenogeneic collagen matrix (XCM); 3) recombinant human platelet-derived growth factor (rhPDGF); 4) enamel matrix derivative (EMD); 5) guided tissue regeneration (GTR); 6) living cellular construct (LCC), all of which are used in conjunction with coronally advanced flaps as alternatives to autogenous donor tissue. The decision tree for treatments of Miller recession-type defects are also discussed.

Free Gingival Graft versus Mucograft: Histological Evaluation

INTRODUCTION:

The correction of the gingival recession is of esthetical and functional significance, but the tissue regeneration can only be confirmed by a histological examination.

AIM:

This study aims to make a comparison between the free gingival graft and the autograft.

MATERIAL AND METHODS:

This study included 24 patients with single and multiple gingival recessions. Twelve patients were treated with a free gingival graft and the other twelve with a micrograft. Six months after the surgical procedure, a micro-punch biopsy of the transplantation area was performed. The tissue was histologically evaluated, graded in 4 categories: immature, mature, fragmented and edematous collagen tissue. The elastic fibres were also examined and graded in three categories: with a normal structure, fragmented rare and fragmented multiplied.

RESULTS:

Regarding the type of collagen tissue that was present, there was a significant difference between the two groups of patients, with a larger number of patients treated with a micrograft showing a presence of mature tissue, compared to the patients treated with a free gingival graft. A larger number of patients in both of the groups displayed elastic fibres with a rare fragmented structure; 33.3% of the patients showed a normal structure; 50% demonstrated a normal structure.

CONCLUSION:

The patients treated with a free gingival graft showed a larger presence of fragmented collagen tissue and fragmented elastic fibres, whereas a mature tissue was predominantly present in the surgical area where a Geistlich Mucograft was placed.

In vitro models for evaluation of periodontal wound healing/regeneration

Periodontal wound healing and regeneration are highly complex processes, involving cells, matrices, molecules and genes that must be properly choreographed and orchestrated. As we attempt to understand and influence these clinical entities, we need experimental models to mimic the various aspects of human wound healing and regeneration. In vivo animal models that simulate clinical situations of humans can be costly and cumbersome. In vitro models have been devised to dissect wound healing/regeneration processes into discrete, analyzable steps. For soft tissue (e.g. gingival) healing, in vitro models range from simple culture of cells grown in monolayers and exposed to biological modulators or physical effectors and materials, to models in which cells are 'injured' by scraping and subsequently the 'wound' is filled with new or migrating cells, to three-dimensional models of epithelial-mesenchymal recombination or tissue explants. The cells employed are gingival keratinocytes, fibroblasts or endothelial cells, and their proliferation, migration, attachment, differentiation, survival, gene expression, matrix production or capillary formation are measured. Studies of periodontal regeneration also include periodontal ligament fibroblasts or progenitors, osteoblasts or osteoprogenitors, and cementoblasts. Regeneration models measure cellular proliferation, attachment and migration, as well as gene expression, transfer and differentiation into a mineralizing phenotype and biomineralization. Only by integrating data from models on all levels (i.e. a single cell to the whole organism) can various critical aspects of periodontal wound healing/regeneration be fully evaluated.

Twenty years of enamel matrix derivative: the past, the present and the future

BACGROUND

On June 5th, 2015 at Europerio 8, a group of leading experts were gathered to discuss what has now been 20 years of documented evidence supporting the clinical use of enamel matrix derivative (EMD). Original experiments led by Lars Hammarström demonstrated that enamel matrix proteins could serve as key regenerative proteins capable of promoting periodontal regeneration including new cementum, with functionally oriented inserting new periodontal ligament fibres, and new alveolar bone formation. This pioneering work and vision by Lars Hammarström has paved the way to an enormous amount of publications related to its biological basis and clinical use. Twenty years later, it is clear that all these studies have greatly contributed to our understanding of how biologics can act as mediators for periodontal regeneration and have provided additional clinical means to support tissue regeneration of the periodontium.

AIMS

This review article aims to: (1) provide the biological background necessary to understand the rational for the use of EMD for periodontal regeneration, (2) present animal and human histological evidence of periodontal regeneration following EMD application, (3) provide clinically relevant indications for the use of EMD and (4) discuss future avenues of research including key early findings leading to the development of Osteogain, a new carrier system for EMD specifically developed with better protein adsorption to bone grafting materials.

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).

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.

Coverage of Miller class I and II gingival recessions treated with subepithelial connective tissue graft, acellular dermal matrix, and enamel matrix proteins. Pilot study

Abstract Objective The aim of this study was to compare clinical findings obtained in the treatment of gingival recessions using subepithelial connective tissue graft (SECT), acellular dermal matrix (ADM), and enamel matrix proteins (EMP). Material and method Twelve patients with Miller class I and II recession in the canines or upper premolars were randomly divided into groups to receive treatments using SECT, ADM, or EMP. Clinical measurements were performed before and three months after surgical procedures. The data evaluated were as follows: percentage of root coverage, height and width of gingival recession, probe depth, clinical attachment level, and height and thickness of keratinized gingiva. The Kruskal-Wallis test complemented by Dunn’s test was used to perform the between-group, analysis and the Wilcoxon test was used to perform the within-groups analysis. The tests were applied at the 95% confidence level. Result The SECT and ADM groups had a higher percentage of root coverage and greater reduction in the height and width of gingival recessions compared to the EMP group (p<0.05). Conclusion The SECT and ADM are more effective in treating gingival recessions than EMP.

A Prospective, Case-Controlled Study Evaluating the Use of Enamel Matrix Derivative on Human Buccal Recession Defects: A Human Histologic Examination

BACKGROUND

Connective tissue grafts (CTGs) and coronally advanced flaps (CAFs) do not regenerate periodontal attachment apparatus when used to treat gingival recessions (GRs). Instead of generating new bone, cementum, and inserting periodontal ligament fibers, CTG+CAF repairs through a long epithelial junction and connective tissue attachment. Enamel matrix derivatives (EMDs) have demonstrated proof-of-principle that periodontal regeneration can be achieved, although data are limited.

METHODS

Three patients, each requiring extraction of four premolars before orthodontic treatment, were enrolled in a randomized, open-label study. Two months after induction of Miller Class I and II GR, each patient received EMD+CAF for three teeth and CTG+CAF for one tooth for root coverage. Nine months after root coverage, all four premolars from each of the three patients were surgically extracted en bloc for histologic and microcomputed tomography (micro-CT) analysis, looking for evidence of periodontal regeneration. Standard clinical measurements, radiographs, and intraoral photographs were taken over prescribed time points.

RESULTS

Seven of the nine teeth treated with EMD+CAF demonstrated varying degrees of periodontal regeneration, detailed through histology with new bone, cementum, and inserting fibers. Micro-CT corroborated these findings. None of the three teeth treated with CTG+CAF showed periodontal regeneration. Clinical measurements were comparable for both treatments. One instance of root resorption and ankylosis was noted with EMD+CAF.

CONCLUSIONS

EMD+CAF continues to show histologic evidence of periodontal regeneration via human histology, this being the largest study (nine teeth) examining its effect when treating GR. The mechanism of action, ideal patient profile, and criteria leading to predictable regeneration are in need of further exploration.

Vascularization after treatment of gingival recession defects with platelet-rich fibrin or connective tissue graft

OBJECTIVE

The aim of this study was to evaluate histologically the following treatment of bilateral localized gingival recessions with coronally advanced flap (CAF) combined with platelet-rich fibrin (PRF) or subepithelial connective tissue graft (SCTG).

MATERIALS AND METHODS

Tissue samples were harvested from 14 subjects either 1 or 6 months after the surgeries. The 2-mm punch biopsies were obtained from the mid-portion of the grafted sites. Neutral buffered formalin fixed, paraffin-embedded 5-μm thick tissue sections were stained with hematoxylin eosin and Masson's trichrome in order to analyze the collagen framework, epithelium thickness and rete-peg length. Multiple sequential sections were cut from paraffin-embedded blocks of tissue and immunohistochemically prepared for detection of vascular endothelial growth factor, CD31 and CD34, for the assessment of vascularization.

RESULTS

Rete peg formation was significantly increased in the sites treated with PRF compared to the SCTG group after 6 months (p < 0.05). On the contrary, the number of vessels was increased in the SCTG group compared to the PRF group after 6 months (p < 0.05). No statistically significant differences were observed in the collagen density. Staining intensity of CD31 increased in submucosal area of PRF group than SCTG group after 1 month. Higher staining intensity of CD34 was observed in the submucosal area of PRF group compared with SCTG group after 6 months.

CONCLUSIONS

The results of the present study suggest that in histological evaluation because of its biological compounds, PRF results earlier vessel formation and tissue maturation compared to connective tissue graft.

CLINICAL RELEVANCE

PRF regulated the vascular response associated with an earlier wound healing.

Bone-added periodontal plastic surgery: a new approach in esthetic dentistry

This article proposes a combined technique including bone grafting, connective tissue graft, and coronally advanced flap to create some space for simultaneous bone regrowth and root coverage.

A 23 year-old female was referred to our private clinic with a severe class II Miller recession and lack of attached gingiva. The suggested treatment plan comprised of root coverage combined with xenograft bone particles.

The grafted area healed well and full coverage was achieved at 12-month follow-up visit. Bone-added periodontal plastic surgery can be considered as a practical procedure for management of deep gingival recession without buccal bone plate.

Flap approaches in plastic periodontal and implant surgery: critical elements in design and execution

AIM

To identify critical elements in design and execution of coronally advanced flap, lateral positioned flap and their variations for the treatment of facial gingival recessions or peri-implant soft tissue dehiscences.

MATERIALS AND METHODS

Clinical studies were identified with both electronic and hand searches, and examined for the following aspects: flap design and incision techniques, flap elevation, root conditioning, flap mobility, flap stability and suturing. Moreover, prognostic factors for complete recession coverage were identified.

RESULTS

Some critical elements are evident in flap design and execution: the dimension and the thickness of tissue positioned over the denuded roots; the use on root surface of enamel matrix derivate; the stability and suturing of the flap in a position coronal to the cemento-enamel junction. The pre-determination of the clinical cemento-enamel junction, smoking status, operator surgical skills and the compliance to a supportive care programme have a role in obtaining and maintaining a complete root coverage.

CONCLUSIONS

Different flap approaches are available when performing periodontal plastic surgery, resulting in a great variability in clinical outcomes. The possibility of using pedicle flaps alone to achieve complete soft tissue coverage of facial implant dehiscence has not yet been investigated.

Leptin effects on the regenerative capacity of human periodontal cells

Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactive molecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL) cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGFβ1, and VEGFA) and transcription (RUNX2) factors as well as matrix molecules (collagen, and periostin) and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.

Beneficial effects of adiponectin on periodontal ligament cells under normal and regenerative conditions

Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-α expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.

Regulation of regenerative periodontal healing by NAMPT

Periodontitis is an inflammatory disease characterized by destruction of the tooth-supporting tissues. Obese individuals have an increased risk of periodontitis, and elevated circulating levels of nicotinamide phosphoribosyltransferase (NAMPT) may be a pathomechanistic link between both diseases. Recently, increased levels of NAMPT have also been found in patients with periodontitis, irrespective of the presence of obesity. This in vitro study sought to examine the effects of NAMPT on the regenerative capacity of human periodontal ligament (PDL) cells and, thereby, periodontal healing. PDL cells treated with enamel matrix derivative (EMD), which was used to mimic regenerative healing conditions in vitro, were grown in the presence and absence of NAMPT for up to 14 d. EMD stimulated significantly (P < 0.05) the expression of growth factors and their receptors, matrix molecules, osteogenesis-associated factors, and wound closure and calcium accumulation. In the presence of NAMPT, all these stimulatory effects were significantly (P < 0.05) reduced. In conclusion, the beneficial effects of EMD on a number of PDL cell functions critical for periodontal regeneration are counteracted by NAMPT. Enhanced levels of NAMPT, as found in obesity and periodontal inflammation, may compromise the regenerative capacity of PDL cells and, thereby, periodontal healing in the presence of EMD.

Connective tissue graft vs. emdogain: A new approach to compare the outcomes

Background:

The aim of this clinical trial study was to clinically evaluate the use of enamel matrix protein derivative combined with the coronally positioned flap to treat gingival recession compared to the subepithelial connective tissue graft by a new method to obtain denuded root surface area.

Materials and Methods:

Thirteen patients, each with two or more similar bilateral Miller class I or II gingival recession (40 recessions) were randomly assigned to the test (enamel matrix protein derivative + coronally positioned flap) or control group (subepithelial connective tissue graft). Recession depth, width, probing depth, keratinized gingival, and plaque index were recorded at baseline and at one, three, and six months after treatment. A stent was used to measure the denuded root surface area at each examination session. Results were analyzed using Kolmogorov-Smirnov, Wilcoxon, Friedman, paired-sample t test.

Results:

The average percentages of root coverage for control and test groups were 63.3% and 55%, respectively. Both groups showed significant keratinized gingival increase (P < 0.05). Recession depth decreased significantly in both groups. Root surface area was improved significantly from baseline with no significant difference between the two study groups (P > 0.05). The results of Friedman test were significant for clinical indices (P < 0.05), except for probing depth in control group (P = 0.166).

Conclusion:

Enamel matrix protein derivative showed the same results as subepithelial connective tissue graft with relatively easy procedure to perform and low patient morbidity.

The effectiveness of enamel matrix protein (Emdogain(®)) in combination with coronally advanced flap in the treatment of multiple marginal tissue recession: A clinical study

Background:

Gingival recession resulting in root exposure is a common problem faced by clinicians. This clinical study compared the results obtained by treating gingival recession using enamel matrix derivative (Emdogain gel^®) along with coronally positioned flap and coronally positioned flap alone.

Materials and Methods:

Twenty patients with a total of 46 gingival recession defects, each patient with a minimum of two recession defects, were included in the study. The test group, which consisted of 10 patients with 22 recession defects, was treated by enamel matrix derivatives (Emdogain gel) in combination with a coronally positioned flap, while the control group, which consisted of 10 patients with 24 gingival recession defects, was treated with 24% ethylenediaminetetraacetic acid (EDTA; Prefgel^®) in combination with coronally positioned flap.

Results:

Student's paired and unpaired t-test was used for statistical analysis. If the probability value (P) was less than 0.05, it was considered significant. Data from this study demonstrated that application of (EMD) Emdogain gel resulted in a statistically significant increase in root coverage, gain in the clinical attachment level (CAL), and probing pocket depth (PPD) reduction when compared with coronally advanced flap (CAF) alone, but there was no statistically significant difference in the width of keratinized gingiva (WKG) between the two groups.

Enamel matrix protein derivatives: role in periodontal regeneration

The role of regenerative periodontal therapy is the reconstitution of lost periodontal structures, ie, new formation of root cementum, periodontal ligament, and alveolar bone. The outcome of basic research has pointed to the important role of enamel matrix protein derivative (EMD) in periodontal wound healing. Histologic results from animal and human studies have shown that treatment with EMD promotes periodontal regeneration. Moreover, clinical studies have indicated that treatment with EMD positively influences periodontal wound healing in humans. The goal of this paper is to review the existing literature on EMD.

The free rotated papilla autograft--a bilaminar procedure for the coverage of multiple shallow gingival recessions: a biometric evaluation

The present clinical study was attempted to evaluate biometrically the predictability of free rotated papilla autograft for multiple shallow gingival recessions.

MATERIALS AND METHODS

Fifteen systemically healthy patients with multiple gingival recessions underwent the procedure the probing depth, percentage of root coverage width of keratinized gingiva, width of attached gingiva were recorded at baseline 3 and 12 months.

RESULTS

All parameters significantly improved from baseline to 12 months. The mean probing depth 1 mm ± 0 mm at baseline which was increased to 1.175 ± 0.245 mm at the end of 3 months and remained same at 12 months. The mean gingival recession was 2.35 ± 0.516 mm at baseline which was improved to 0.425 ± 0.245 mm at the end of 3 months and remained same at 12 months. The mean width of keratinized gingiva was 1.157 ± 0.245 mm at baseline which was improved to 3.15 ± 0.489 mm at the end of 3 months and remained same at 12 months. The mean width of attached gingiva 0.175 ± 0.245 mm at baseline which was improved to 1.975 ± 0.415 mm at the end of 3 months and remained same at 12 months.

CONCLUSION

The mucogingival surgery resulted in achieving high degree of success and predictability as well as an excellent esthetic outcome.

CLINICAL SIGNIFICANCE

Free rotated papilla autograft is a predictable treatment modality for multiple shallow gingival recessions.