Multiple Gingival Recession Defects

PERIODONTICS, dentistry, root coverage VISTA, Periosteal Pedicle, Graft Multiple Gingival Recession Defects, Coronally Advanced Flap, GEM 21S, oA 9-Month Clinical Study

1. Multiple Gingival Recession Defects Treated with Coronally Advanced Flap and Either the VISTA Technique Enhanced with GEM 21S or Periosteal Pedicle Graft: A 9-Month Clinical Study   Shruti Raju Dandu , Private Practice, Visakhapatnam, India. K . Raja V. Murthy. Professor and Head of Department of Periodontology , GITAM Dental College and Hospital, Visakhapatnam, India. Int J Periodontics Restorative Dent 2016

2. INTRODUCTION. Gingival recession is defined as “the displacement of soft tissue margin apical to CEJ with exposure of root surface .” Successful coverage of exposed roots for esthetic and functional reasons has been the objective of various mucogingival procedures . Multiple techniques have been developed to obtain predictable root coverage. The purpose of developing new techniques is to increase predictability, reduce patient discomfort, minimize the number of surgical sites, and satisfy the patient’s esthetic demands, which include the final color and tissue blend of the grafted area.

3. “Marginal tissue recession is defined as the displacement of the soft tissue margin apical to the cement-enamel junction.”- AAP 1999 “Gingival recession is defined as the location of gingival margin apical to the cemento -enamel junction.” – GPT 2001 “Gingival recession is defined as the apical shift of the gingival margin with respect to the cemento ‐enamel junction (CEJ); ( Pini Prato et al Ann Periodontal 1999) it is associated with attachment loss and with exposure of the root surface to the oral environment” 2017 World workshop.

4. The criteria for successful root coverage are as follows: The gingival margin is on CEJ in Class I, Class II gingival recession, the depth of gingival sulcus is within 2 mm, there is no bleeding on probing, there is no hypersensitivity, and color match with adjacent tissue is esthetically harmonious. (  Miller PD., Jr A classification of marginal tissue recession.  Int J Periodont Rest Dent.  1985)

5. techniques mainly CAF, Zuchelli’s technique and pouch and tunnel techniques, the problems associated are the compromised vascularity since large surgical sites are involved , extensive avascular surface, longer surgical time and increase in patient morbidity, also the papillary integrity is not maintained since there is a creation of surgical and anatomic papillae, when there is tension during coronal repositioning there are less success rates, vestibular shortening and sometimes there is scar formation at the vertical incisions

6. The extent and predictability of any root coverage procedure for the treatment of recession defects is dependent on the vascularity maintained at the surgical site. Since the introduction of the supraperiosteal tunnel technique in 1994, it has been used widely with a number of modifications to treat isolated as well as multiple adjacent gingival recession. In cases of MAGRD, especially in the anterior esthetic zone it is important to maintain the integrity of the papilla thereby maintaining esthetics and also the vascularity . The interdental papilla has a very rich source of vascularity since it is supplied from three sources, the supraperiosteal blood vessels, the vessels from the PDL and the arterioles emerging from the crest of the interdental bone. Also subperiosteal tunneling beyond the mucogingival junction allows for low tension coronal repositioning of the gingiva . A vestibular incision allows for easy access for tunneling than the intrasulcular tunneling approach. And hence keeping into consideration the above factors Zadeh et al in 2011, gave vestibular incision subperiosteal tunnel access.

7. Vestibular incision subperiosteal tunnel access (VISTA) is a more recent, minimally invasive approach used for the treatment of both isolated and multiple contiguous recession defects . Zadeh et al.2011 . Introduced a new surgical technique - vestibular incision subperiosteal tunnel access (VISTA). In this a access incision was made in the maxillary anterior frenum area for recessions crossing the midline. The access incision was made adjacent to the teeth to be treated. Elevation of a full thickness sub- periosteal is made by tunneling with the VISTA instruments. Tunnel is mobilized until low tension coronal repositioning is achieved. A novel suturing technique of coronally anchored suspensory sutures is used. The author has used recombinant human platelet-derived growth factor BB saturated onto a matrix of beta– tricalcium phosphate over root dehiscences for root coverage. Two documented case showed successful root coverage and long term stable results

8. Nevins et al reported recombinant human platelet-derived growth factor ( rhPDGF ) as a potent mitogen and chemotactic protein for periodontal ligament fibroblasts and alveolar bone cells.

9. The periosteum has a rich vascular plexus, and its osteogenic potential has received considerable attention as a grafting material for repair of bone and joint defects. The use of a pedicle flap to cover the graft improves root coverage predictability as it provides the graft with additional blood supply and also improves the esthetic result. The purpose of this study was to compare and evaluate the clinical efficacy of the VISTA technique incorporating Bio-Gide ( Geistlich ) membrane enhanced with GEM 21S ( Osteohealth ) with periosteal pedicle graft and the coronal advancement of the flap in the treat- ment of multiple gingival recession defects.

10. Materials and methods A total of 15 patients (10 men and 5 women) with a mean age of 36.13 years and a chief complaint of dentinal hypersensitivity and/or esthetic concern with bilateral Miller Class I or II gingival recession defects were enrolled in the study. A single blinded, randomized, split- mouth clinical trial was designed. A total of 30 sites in 15 patients were randomly divided into experimental site A and experimental site B as per split-mouth design using the coin toss method.

11. Inclusion criteria Men or women between 18 and 60 years of age Miller Class I or II gingival recession defects Good systemic health No history of smoking No history of surgical treatment in the delineated area for at least 2 years prior to the study Vital teeth, free of faulty restorations The study protocol involved a screening appointment, followed by initial therapy, surgical therapy, and postoperative evaluation after 3, 6, and 9 months .

12. Initial therapy and clinical measurements Prior to surgery patients received professional oral prophylaxis, oral hygiene instructions, and occlusal adjustments as per individual requirements. Deep cervical defects were restored with resin-modified glass- ionomer cement (GC Fuji PLUS, GC America). A customized acrylic stent was made with guiding grooves on each experimental tooth angled toward the deepest part ( ie , the midfacial part) of the recession. One trained examiner performed all the clinical measurements on the midbuccal aspect of the gingival recession defects using a UNC-15 periodontal probe. Prior to surgery and 9 months after surgery the following clinical parameters were assessed: Resin ionomer materials have many properties that allow the successful restoration of NCCLs and those in the subgingival area including self-adhesion to dentin and enamel, epithelial and connective tissue adherence, better mechanical strength, and smoother surface than conventional glass ionomers Epithelial and connective tissue adherence to resin ionomer restorative materials is observed during the healing process

13. Probing pocket depth was measured from the gingival margin to the base of the gingival sulcus . Vertical depth of the recession (RD) was measured as the distance from the cementoenamel junction (CEJ) to the gingival margin. Clinical attachment level (CAL) was measured from the CEJ to the base of the gingival sulcus with the help of UNC probing using the acrylic stent. Width of keratinized tissue (WKT) was measured from the mucogingival junction to the gingival margin. Percentage of root coverage was calculated as: Postsurgical discomfort levels were noted at the end of 1 day, 1 week, and 1 month using a subjective pain scale ranging from 0 (no pain) to 5 (worst possible pain).

14. Surgical procedure

15. Experimental site A was treated using the VISTA technique with bioresorbable collagen membrane (Bio-Gide) enhanced with re- combinant human platelet-derived growth factor BB ( rhPDGF -BB) (GEM 21S) as described by Zadeh .

16. Geistlich Bio-Gide® is designed with a smooth, compact upper layer which is an ideal catalyst for the attachment of fibroblasts that lead to favorable healing of the gingival tissue. The dense porous lower layer acts as a guide for osteoblasts , which become the foundation for optimal bone formation and healing. These properties, in combination with an optimally timed barrier function, prevent premature growth of soft-tissue into the defect and create an environment for the appropriate cascade of biological events

17. BioMimetic Therapeutics, Inc. announced ON 7 TH June 2006 that it has received approval from the U.S. Food and Drug Administration (FDA) for its lead product, GEM 21S(R). The first BioMimetic product to be approved by the FDA, GEM 21S is a fully synthetic regeneration system for the treatment of periodontal bone defects and associated gingival recession. GEM 21S is composed of the tissue growth factor, recombinant human Platelet-Derived Growth Factor ( rhPDGF -BB), and a synthetic bone matrix, Beta- tricalcium phosphate (a-TCP). It is the first totally synthetic product combining a purified recombinant growth factor with a synthetic bone matrix to be approved by the FDA for human application.

18. A vestibular access incision was located at an optimal position to gain access to the recession defects. The incision was made through the periosteum using a no. 11 surgical blade (Bard-Parker) to elevate a subperiosteal tunnel, exposing the facial osseous plate A periotome (PT2, Hu-Freidy ) was used to elevate the periosteum and create the subperiosteal tunnel. It is important to extend the tunnel elevation sufficiently beyond the mucogingival margin as well as through the gingival sulci of the teeth being augmented to allow for low-tension coronal repositioning of the gingiva

19. This tunnel was extended at least one or two teeth beyond the teeth requiring root coverage to mobilize gingival margins and facilitate coronal repositioning. Additionally , the subperiosteal tunnel was extended interproximally under each papilla as far as the embrasure space permitted , without making any surface incisions through the papillae . A resorbable collagen membrane was then trimmed to fit the dimensions of the surgical area

20. Prior to its insertion, the membrane was saturated with 0.3 mg/ mL rhPDGF - BB for a minimum of 10 minutes in a sterile dappen dish. A fine-tipped serrated forceps was used to insert the collagen membrane inside the subperiosteal tunnel. The membrane and mucogingival complex were then advanced coronally and stabilized in the new position with a coronally anchored suturing technique

21. The use of periosteum for the treatment of gingival recession defect. ( (e) The periosteal graft is covered with the overlying coronally advanced flap which is sutured using 4–0 silk suture. (f) Satisfactory treatment outcome. (a) Clinical photograph showing gingival recession defect in relation to the maxillary first right premolar. (b) A partial thickness flap lifted to expose the underlying periosteum covering the alveolar bone. (c) The periosteum which is separated from the underlying bone. d) The periosteum is used as a pedicle graft for covering the recession defect. ( (e) The periosteal graft is covered with the overlying coronally advanced flap which is sutured using 4–0 silk suture. . (f) Satisfactory treatment outcome.

22. Experimental site B was treated with a periosteal pedicle graft (PPG) and coronally advanced flap as described by Mahajan An intrasulcular incision on the buccal aspect of the involved tooth was made with a no. 15 surgical blade (Bard-Parker ). A horizontal right angle incision was made into the adjacent interdental papilla at or slightly coronal to the level of the CEJ of the tooth presenting the defect. Two divergent vertical incisions were made starting at least 0.5 mm from the gingival margin of the adjacent teeth and extending into the alveolar mucosa

23. The intrasulcular horizontal right angle incision and the vertical incisions were connected, and a trapezoidal full-thickness flap was raised 3 to 4 mm apical to the bone dehiscence. From there, a partial-thickness dissection was performed to allow for coronal positioning of the flap. An incision was made through the periosteum , where the flap was still attached to bone, to create a partial-thickness flap. The partial-thickness flap was extended to expose a sufficient amount of the periosteum , which was then separated from the underlying bone using a periosteal elevator The process of separating the periosteum was initiated at its apical extent, which was then lifted slowly in a coronal direction. The periosteum was not separated completely from the underlying bone; it remained attached at its coronal end De- epithelization of the papillae adjacent to the defect was performed.

24. The exposed affected root surface was scaled and planed with a Gracey curette to produce a decontaminated , smooth, flattened surface. The PPG thus obtained was then turned over the exposed root surface and stabilized The flap was coronally positioned and sutured using the sling suture technique. The releasing incisions were closed with interrupted sutures

25. Results All patients tolerated the surgical procedures well, experienced no postoperative complications, and were compliant with the study protocol. Study teeth were free of visible plaque and gingival inflammation throughout the study. The mean baseline recession depth, WKT, probing depth, and CAL showed no statistical difference ( P > .05) between the experimental sites. Both study groups showed a statistically significant reduction in mean recession depth ( P < .001) at 3, 6, and 9 months when compared with baseline. Statistically sig- nificant gain in the WKT ( P < .001) and CAL ( P < .05) was obtained at 9 months when compared with baseline in both groups. The mean reduction in recession depth was statistically higher in site A when compared with site B at 3, 6, and 9 months ( P < .05), similar to other clinical parameters such as gain in the WKT and CAL. No statistically significant difference was observed in probing depth from baseline to 9 months follow-up between the groups ( P > .05) (Table 1).

26. The mean percentage of root coverage achieved was 87.37 ± 17.78% and 71.84 ± 19.25% at 9 months from baseline in VISTA- treated sites and PPG-treated sites, respectively. Site A showed a significantly higher percentage of root coverage compared with site B ( P < .05 ) Postsurgical discomfort levels (PSDL) were assessed at day 1, at the end of 1 week, and at the 1-month follow-up in both sites. In the VISTA group on day 1, 10 subjects had a PSDL score of 2; 4 subjects scored 1, and 1 subject scored 3. At 1 week, 11 subjects scored 0 and 4 subjects scored 1. At the end of 1 month, all 15 subjects scored 0. In the PPG group on day 1, 9 subjects scored 3, 4 subjects scored 5, and 2 subjects scored 2. At 1 week, 10 subjects scored 1, 4 subjects scored 2, and 1 subject scored 3. At the end of 1 month, 11 subjects scored 0 and 4 subjects scored 1.

27. Discussion   Chambrone et al have reported that the subepithelial connective tissue graft (SCTG) seems to produce more predictable results when both root coverage and WKT gain are expected. The bilaminar technique using the subepithelial connective tissue graft is considered the current gold standard technique for root coverage. Its advantages over the conventional gingival graft procedure include good gingival contour and less likelihood of keloid formation. However , the limitations of SCTG include the need for harvesting at a distant donor site, limited tissue availability when donor tissue thickness is insufficient or the greater palatine neurovascular complex is in proximity to the CEJ of the premolars , and increased potential for post harvesting morbidity and discomfort. In patients with multiple contiguous gingival recession defects these disadvantages are even more pronounced, since optimizing esthetic results in part depends on simultaneous treatment of all contiguous recessions. Other novel methods of root coverage are needed to overcome these drawbacks.

28. VISTA allows management of multiple recession defects, maintains the papillary integrity, and avoids vertical releasing incisions. McGuire et al and McGuire and Scheyer , in comparing the effectiveness of rhP - DGF-BB with SCTG, demonstrated clinically significant improvements from baseline through week 24, with the growth factor–mediated treatment approaching the efficacy of the SCTG on parameters such as recession depth reduction and percent root coverage

29. presence of cell-surface receptors for PDGF on PDL and alveolar bone cells and elucidating PDGF’ has stimulatory effect on the proliferation and chemotaxis of these cells. Additionally, recombinant human PDGF-BB ( rhPDGF -BB) has been shown to promote the regeneration of periodontal tissue, including bone, cementum , and PDL Beta tricalcium phosphate is a purified, multicrystalline , porous form of calcium phosphate with a Ca:PO4 ratio similar to that of natural bone mineral. When placed under a membrane, the þ -TCP prevents membrane collapse against the root surface and provides a matrix or scaffolding for new bone formation. It also facilitates the stabilization of the blood clot.

30. The VISTA technique incorporating the Bio- Gide membrane enhanced with GEM 21S serves as an alternative to SCTG, as rhPDGF -BB with the collagen barrier allows simultaneous treatment of multiple gingival recession defects without requiring secondary harvesting procedures. The adult human periosteum is highly vascular and is known to contain fibroblasts and osteoblasts , their progenitor cells, and mesenchymal stem cells. In all age groups, the cells of the periosteum retain the ability to differentiate into fibroblasts, osteoblasts , chondrocytes , adipocytes , and skeletal myocytes . The results of this study demonstrated that both the VISTA technique using Bio-Gide enhanced with GEM 21S and PPG, covered by a coronally positioned flap, were effective in the treatment of gingival recession defects≥ 2 mm. The presence of a resin- modified glass- ionomer restoration may not interfere with the percentage of soft tissue coverage when a coronally advanced flap is used for the treatment of Miller Class I and II gingival recessions associated with noncarious cervical lesions.

31. Both sites showed significant root coverage (87.37% and 71.84% for VISTA and PPG, respectively), gain in the WKT, and clinical attachment gain at 9 months postoperative. The difference in reduction in probing depth between the two procedures was not statistically significant. VISTA- treated sites resulted in a statistically significant increase in the percentage of root coverage when compared to PPG-treated sites. Zadeh noted 100% root coverage for all growth factor–mediated, minimally invasive VISTA–treated teeth, along with 1- to 2-mm gains in keratinized gingiva at the end of the 12-month follow-up period.

32. At the end of 1 year, Mahajan in his case series incorporating the periosteal pedicle flap observed 90.95% root coverage, with a significant increase in the widths of keratinized and attached gingiva no change was observed in probing depths In the VISTA technique, access is broader and is made in the vestibule, where a single vestibular incision can provide access to an entire region, including instrument access to the underlying alveolar bone and root dehiscences . The remote incision reduces the possibility of traumatizing the gingiva of the teeth being treated.

33. Critical to the success of VISTA is a careful subperiosteal dissection that reduces the tension of the gingival margin during coronal advancement while maintaining the anatomical integrity of the interdental papillae by avoiding papillary reflection. Coronally anchored bonded sutures are retained for 3 weeks to allow for immobilization of the gingival margin during the initial healing phases. The gingival margin, with its attached collagen membrane, is advanced to the most coronal level of the adjacent interproximal papillae rather than to the CEJ

34. The most critical phase of regenerative periodontal therapy is the reattachment of collagen fibers to the root surface. During the inverted periosteal pedicle graft healing, the cells with the potential to regenerate cementum and periodontal ligament are the first to populate the root surface. Osteoblasts and their progenitor cells are immediately behind the fibroblasts and populate the defect. The periosteal pedicle graft thus places the proper cells in the proper location for regeneration of the defect. Any area without a firm barrier to tooth apposition is likely to allow the invasion of gingival cells, resulting in surgical failure. The periosteum is a natural barrier membrane preventing fibrous and epithelial cell invasion into the grafted site, allowing the slower- proliferating osteoblasts to populate a scaffold  

35. The VISTA group presented better esthetics, especially in terms of contour and texture, when compared with the PPG group. The color match was similar in both groups. When the results were compared in terms of patient satisfaction, VISTA emerged as the preferred treatment option as it was rated better in terms of comfort during and after the surgical procedure and overall satisfaction by the subjects. The better patient satisfaction obtained by the VISTA may be attributed to the less traumatic surgical procedure. This not only reduces intraoperative time but also favors uneventful post- operative healing; in contrast, the PPG techniques caused the patient more pain due to the need to surgically open the site apically to obtain donor tissue . The study was limited by the absence of histologic assessment of the type of attachment obtained and in being restricted to Miller Class I and II gingival recession defects.

36. Conclusions Within the limits of the study, it is reasonable to conclude that VISTA may be deemed a predictable, effective , minimally invasive, and viable alternative to the PPG technique for obtaining optimal patient-based outcomes. In light of the potential benefits of VISTA to patients, further histologic evidence is warranted. On the other hand, PPG is cost effective and has the advantages of being an autogenous graft .  

37. THANKYOU