Periodontal Soft Tissue Non–Root Coverage Procedures: A Systematic Review From the AAP Regeneration Workshop

Patients' Values in Clinical Decision-Making

OBJECTIVE

Shared decision-making involves the participation of patient and dental practitioner. Well-informed decision-making requires that both parties understand important concepts that may influence the decision. This fourth article in a series of 4 aims to discuss the importance of patients' values when a clinical decision is made.

METHODS

We report on how to incorporate important concepts for well-informed, shared decision-making. Here, we present patient values as an important issue, in addition to previously established topics such as the risk of bias of a study, cost-effectiveness of treatment approaches, and a comparison of therapeutic benefit with potential side effects.

RESULTS

We provide 2 clinical examples and suggestions for a decision tree, based on the available evidence.

CONCLUSION

The information reported in this article may improve the relationship between patient and dental practitioner, resulting in more well-informed clinical decisions.

Soft tissue substitutes in non-root coverage procedures: a systematic review and meta-analysis

OBJECTIVES

The present systematic review compared the effectiveness of soft tissue substitutes (STSs) and autogenous free gingival grafts (FGGs) in non-root-coverage procedures to increase keratinized tissue (KT) width around teeth.

MATERIALS AND METHODS

Included studies fulfilled the following main eligibility criteria: (a) preclinical in vivo or human controlled trials using FGG as control, (b) non-root-coverage procedures, and (c) assessment of KT width. Meta-analysis was performed on the gain in KT width (primary outcome variable) and several secondary variables.

RESULTS

Eight human trials with short observation time evaluating five different STSs were identified. FGG yielded consistently significantly (p < 0.001) larger increase in KT width irrespective whether the comparison regarded an acellular matrix or a tissue-engineered STS. Further, FGG yielded consistently ≥2 mm KT width postoperatively, while use of STS did not, in the few studies reporting on this outcome. On the other hand, STSs resulted in significantly better aesthetic outcomes and received greater patient preference (p < 0.001).

CONCLUSIONS

Based on relatively limited evidence, in non-root-coverage procedures, FGG (1) resulted consistently in significantly larger increase in KT width compared to STS and (2) yielded consistently ≥2 mm KT width postoperatively, while STSs did not. STSs yielded significantly better aesthetic outcomes, received greater patient preference, and appeared safe.

CLINICAL RELEVANCE

Larger and more predictable increase in KT width is achieved with FGG, but STSs may be considered when aesthetics is important. Clinical studies reporting relevant posttreatment outcomes, e.g., postop KT width ≥2 mm, on the long-term (>6 months) are warranted.

Palatal wound healing using a xenogeneic collagen matrix - histological outcomes of a randomized controlled clinical trial

AIM

The aim of this study was to test whether or not a collagen matrix can improve early wound healing compared to spontaneous healing based on histological and immunohistologic analyses.

METHODS

In 20 volunteers, 6 mm punch biopsies were harvested at the palate. A xenogeneic collagen matrix (XCM) was sutured in one site; the other one was left untreated (control). Biopsies with a diameter of 8 mm were subsequently obtained at 4, 8, 15 and 29 days and histological and immunohistologic analyses were performed.

RESULTS

At day 4, wound bed keratinization amounted to 12.4 ± 7.5% (control) and 18.0 ± 10.2% (XCM). This increased up to day 8 (19.7 ± 25.5% control; 29.1 ± 8.0% XCM) and reached complete keratinization at day 15 in both groups. The quantitative analyses of the superficial compartment measured an increase in the amount of granulation tissue (32-88% control; 14-41% XCM) from day 4 to day 8. Angiogenesis was first detected at 8 days. At day 29, the amount of connective tissue in all compartments reached values similar to the native tissue at baseline.

CONCLUSIONS

The application of a XCM as a wound dressing on palatal wounds might be beneficial in the early stages of wound healing. Further research with a larger sample size is needed to confirm these results.

Assessment of non-carious root surface defects in areas of gingival recession: A descriptive study

Background

The purpose of this descriptive study was to observe the distribution of four different classes of non-carious cervical root surface discrepancies in teeth with gingival recession. Additionally to explore the different treatment modalities in the literature for each of these defects.

Material and Methods

A total of 150 subjects with at least one labial gingival recession were included in the study. 1400 teeth were evaluated using 2.5 X magnification loupes and UNC -15 probe for the presence of the cemento-enamel junction and step like defects according to Pini-Prato’s classification: A-, identifiable CEJ without defect; A+, identifiable CEJ with defect; B-, unidentifiable CEJ without defect, B+, unidentifiable CEJ with defect. Further a comprehensive electronic and hand search of pubmed indexed journals was performed to identify appropriate treatment modalities for these defects and their predictability following restorative/surgical or combination of both.

Results

A total of 1400 teeth with exposed root surfaces were examined (793 Maxillary; 607 mandibular). 499 teeth were A-, 405 were A+, 322 were B+ and 174 were B-. The distribution of these defects in different teeth was: 36% premolars, 32% molars, 21% incisors and 11% canines, collectively 68% in the aesthetic zone.

Conclusions

Majority of these lesions are in the maxillary aesthetic zone. Hence the presence of the CEJ and the defect must be taken into account while managing these defects surgically.

Key words:Cervical abrasion, gingival recession, magnification loupes, root coverage, step defects.

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.

Effects of Ozone Therapy on the Early Healing Period of Deepithelialized Gingival Grafts: A Randomized Placebo-Controlled Clinical Trial

BACKGROUND

This study evaluates the effects of ozone therapy (OT) on the early healing period of deepithelialized gingival grafts (DGG) placed for non-root coverage gingival augmentation by laser Doppler flowmetry (LDF).

METHODS

Thirty-three patients were assigned to study groups: 1) test: DGG + OT; or 2) control group: DGG alone. Thirty patients completed the study. Ozone was applied on DGGs placed in the recipient bed and donor site immediately after surgery and at days 1 and 3 post-surgery. Blood perfusion in the recipient site was measured by LDF on the day of surgery and at 1, 2, 3, 6, 8, 10, and 13 days after surgery. Quality of life (assessed by the Oral Health Impact Profile-14) and pain at donor/recipient sites (assessed by visual analog scale) were also investigated.

RESULTS

Increase in blood perfusion units in the test group was significantly higher than control group at 1, 2, 3, 6, and 8 days post-surgery (P <0.001). Significant differences occurred between test and control groups in terms of visual analog scale values during the first week post-surgery for both donor and recipient sites (P <0.05). The ozone-treated group showed significantly higher quality of life than control group on postoperative day 6 (P = 0.002).

CONCLUSIONS

OT enhanced blood perfusion units in the first postoperative week. This outcome is also consistent with improvement in wound healing, accompanied by an increase in quality of life and decrease in postoperative pain in the test group.

Latent transforming growth factor-β binding proteins (LTBP-1 and LTBP-2) and gingiva keratinization

OBJECTIVE

Transforming growth factor-beta (TGF-β) proteins are involved in epithelial keratinization. The major function of latent TGF-β binding proteins (LTBPs) is modulating TGF-β activity. However, whether LTBP-1 and LTBP-2 play roles in gingiva keratinization remains unclear.

MATERIALS AND METHODS

Human keratinized gingiva and non-keratinized alveolar mucosa were processed for LTBP-1, LTBP-2, cytokeratin-1 (K1), cytokeratin-4 (K4), and TGF-β immunohistochemical (IHC) staining. Porcine heterotopically transplanted connective tissues and newly grown epithelia were harvested for IHC staining. The expression levels of LTBP-1 and LTBP-2 were compared between differentiated and undifferentiated human normal oral keratinocytes (hNOK). The expression of LTBP-1 and LTBP-2 was knocked down in a cell line (OEC-M1) to evaluate the effects on the expression of K1, K4, and involucrin (INV).

RESULTS

In human and porcine specimens, LTBP-2 expression patterns distinguished keratinized and non-keratinized oral epithelia. Western blotting results showed that K1, LTBP-1, and INV proteins were upregulated in differentiated hNOK. In OEC-M1 cells, LTBP-2 knockdown resulted in upregulated the expression of K1 and INV and downregulated the expression of K4. LTBP-1 knockdown resulted in opposite effects.

CONCLUSION

The expression patterns of LTBP-2 differ in keratinized gingiva and non-keratinized mucosa. LTBP-1 and LTBP-2 are involved in the keratinization of oral epithelium; however, the underlying mechanism remains to be elucidated.

Periodontal Soft Tissue Non-Root Coverage Procedures: Practical Applications From the AAP Regeneration Workshop

Focused Clinical Question: What are the indications and clinical applications for gingival augmentation procedures, and what factors guide the choice among treatment options in specific situations? Summary: Although there is still controversy regarding whether there needs to be a minimum amount of attached gingiva to maintain the stability of the gingival margin, prospective and retrospective studies have shown that, in the presence of suboptimal plaque control and clinical inflammation, attachment loss and gingival recession (GR) may result unless a minimum amount of keratinized tissue (KT) and attached gingiva are present. Treatment of mucogingival deformities requires gingival augmentation procedures that address both a functional and esthetic component for the patient. Although free gingival grafts (FGGs) are considered the gold standard for treatment of GR defects to obtain root coverage, augmentation of KT and attached gingiva may be accomplished by FGG or other autogenous grafting options, including the free connective tissue graft, the lateral pedicle graft, and the double papilla technique. In addition, the modified apically repositioned flap can be considered in some instances. Alternatives to autogenous graft tissue include acellular dermal matrix, extracellular matrix membrane, bilayer collagen matrix, and living cellular construct. Conclusions: Understanding the clinical importance of the presence of a minimum amount of attached gingiva in patients with suboptimal hygiene is an important first step in addressing the condition. Patient education to address plaque control and counseling to quit smoking in patients who are smokers help enhance the success of these mucogingival surgical procedures. An analysis of patient-specific factors will help with the appropriate choice of surgical procedures aimed at augmenting the dimension of KT/attached gingival tissue. Evidence supporting the treatment decisions described in this practical application is summarized in the companion papers from the American Academy of Periodontology Regeneration Workshop (Kim and Neiva, J Periodontol 2015;86(Suppl.):S56-S72; Scheyer et al., J Periodontol 2015;86(Suppl.):S73-S76).