Comparison of a Semilunar Coronally Positioned Flap and Conventional Coronally Advanced Flap for the Treatment of Gingival Recession: A Split-mouth, Randomized Prospective Comparative Controlled Clinical Trial

INTRODUCTION

Gingival recession has become one of the most common reasons that urge patients to visit dental clinics, mainly because of its consequences such as root sensitivity and esthetic impairment.¹ Gingival recession is defined by the exposure of root surface resulting from the displacement of the free gingival margin in the apical direction away from cementoenamel junction (CEJ) toward the MGJ. The most common cause of gingival recession is either frequent mechanical trauma caused by incorrect dental brushing or inflammatory periodontal diseases.^1,2 Different surgical RC techniques have been proposed as successful treatment techniques for gingival recession, including using pedicle flaps which is a minimally invasive periodontal surgery.¹ A systematic review has shown that using coronally advanced flap (CAF) leads to successful treatment of class I and II recession (according to Miller).² Despite the success rate with this technique, it has a negative impact on flap tension on blood supply and consequently on clinical outcomes. Furthermore, the vertical releasing incisions may result in shallowing the oral vestibulum and a white scarred incisions, which could compromise the esthetic result.³ In order to overcome these difficulties, Tarnow had suggested using semilunar coronally position flap (SCPF), which is ideal for the upper anterior teeth and premolars that have 2–3 mm recession of the Miller’s class I.^3,4 This technique has shown many advantages: it is simple, fast, and atraumatic; it increases the width of the keratinized gingiva; it did not involve narrowing of the oral vestibule; it required less time to operate; it preserves the blood supply with the absence of the flap tension; and it costs less and does not need sutures.^3,5 However, not needing sutures has affected the results of the clinical parameters and its stability compared to other surgical techniques.⁵ Therefore, many attempts were made to adjust this technique in order to obtain better clinical performance; some of these modifications are suturing the flap,⁶ biological modification of the root surface,⁴ and the use of microscopic surgery.⁴

MATERIALS AND METHODS

RESULTS

The study sample consisted of 20 patients, 4 of them were excluded due to either dropping out during the follow-up period or no adherence to the oral instruction given after surgery. A flow diagram of the study participants is provided (Flowchart 1).

A total of 32 bilateral maxillary buccal gingival recession sites (Miller class I) (1–4.2 mm) were treated in 16 patients (8 males and 8 females) whose age ranged between 19 years and 52 years with a mean of 33 years. The one site was treated with CAF technique (16 defects) and the opposite site was treated with semilunar coronally technique (16 defects). The treated teeth consisted of 1 central, 9 laterals, 5 canines, 15 first premolars, and 2 second premolars.

All patients tolerated the surgical procedures well, and no postoperative complications were reported. Full-mouth VPI and SBI were kept at 20% and below.

For the questionnaire used, Cronbach’s α was 0.8, a value higher than 7, which indicated that it is reliable to use.

DISCUSSION

The purpose of this randomized, controlled split-mouth design study was to compare the clinical efficacy of two types of coronally pedicle flap, namely, semilunar and conventional coronally flaps while using TTC as the biomodified agent for the root surface and modifying in suturing technique. Bilateral recession defects for the same patient allow each patient to have his/her own control. The results of the present trial demonstrated that both techniques with modifications were effective for the treatment of shallow localized gingival recessions.

The TTC root conditioning may remove the smear layer, regulate the adsorption of plasma proteins, enhance adhesion of blood clot, and stimulate the deposition of collagen against the root surface.^12,13 Woodyard et al. used TTC with CAF and reported RC by 67%.¹² George et al. conducted a study in which they used TTC and fibrin glue adhesive fibrin adhesive system (FAS) application with SCPF and reported coverage by 50% in the FAS with TTC group, while the FAS-only group received almost no coverage.¹³

The use of anchorage sutures was to fix and stabilize the flap as coronally as possible for attaining better results. In a previous study, an orthodontic button was used as a passive component for holding sutures, and it attained better stability to the flap in a coronally displaced position.¹⁴

As far as we know, no previous study was conducted using these modifications to these two techniques to study the differences between them in terms of all the clinical parameters and questionnaires adopted by our study.

In the SCPF group, the RC% was 82.3 ± 15.6% and CRC was achieved in five teeth (31.3%) whose defect was treated. Our result of RC% is higher than those presented by Moka et al.¹⁵ and Rana et al.⁶ (66.75% and 42.5%, respectively). However, Bittencourt et al.⁴ and Santana et al.⁵ reported 91.1% and 90.95% (CRC was 9.3%), respectively. More recently, França-Grohmann et al.¹⁶ found the RC% 79.76 ± 17.44 after 1 year and CRC was 33.33% (5 out of 15). Another case series, Santamaria et al.¹⁷ modified the design of the SCPF and achieved a mean RC of 85.4 ± 24.7% and the CRC was 41.6%.

For the CAF, the RC% was 79.8 ± 27.7 and the CRC was accomplished in seven teeth (43.8%) with defects. These results are in accordance with the previous studies.^5,9,18–20 Some studies conducted by Santana et al.²¹ and Moka et al.¹⁵ showed higher RC percentage than our results (96.6% and 93.48%, respectively). However, Jepsen et al.²² and Rana et al.⁶ reported a lower percentage (76.44 ± 26.83% and 42.5%, respectively) than that reported in our present trial.

The absence of full RC in the semilunar CAF for all cases may be due to the scar formation in the place of the semilunar incision (where the scar is vertical to the direction of the displacement of the gingival tissue), and this may cause contract of the gingival margin in the apical direction.²³ The vertical releasing incisions in the conventional CAF are parallel to the displacement side, possibly helping to obtain more CRC.²⁴ However, the anchorage sutures may reverse these forces or decrease it.

Statistically significant differences were detected between groups for the amount of RC, which agrees with other studies.^5,25 However, both techniques were effective for attaining satisfaction and esthetic RC.

The healing process in the area where the pedicle graft is in contact with the denuded root surface consisted of adaptation stage (from 0 days to 4 days), proliferation stage (from 4 days to 21 days), attachment stage (from 27 days to 28 days), and the last stage of healing is maturation stage. It is characterized by the continuous formation of collagen fibers. After 2–3 months, bundles of collagen fibers insert into the cementum layer on the curetted root surface in the apical portion of the recession.²⁶ Therefore, we can take clinical measurements 3 months after surgery and these are in accordance with previous studies.^{6,13,18,20,22,25,27–29}

Both treatment groups showed significant postsurgical improvement for parameters (PD, CAL, GRH, and GRW) when compared with baseline. In the SCPF group, these results are consistent with the previous studies.^{5,6,14–16,30,31} However, no statistically significant difference was observed for the position of the MGJ. The gain in KT and VD may be explained by the healing pattern of the connective tissue that remains exposed. In this case, granular tissue will fill this area (semilunar incision area) and turn to the same tissue that existed before the flap had advanced. The increase in the WKT and TKT is desirable to prevent the recurrence of the condition in the future.³²

Results from the present coronally advanced technique are in agreement with other studies.^{5,6,15,18,20,21,27,28,33} However, the WKT had decreased with statistical significance (p = 0.04), which was consistent with the finding of the previous study conducted by Santana et al.²¹ In previous studies,^18,19,27,29 they showed a slight reduction at the 3-month follow-up. There was a decrease in the VD and position of the MGJ, with a statistically significant difference (p = 0). This can be explained by the results of the coronally displaced tissue by using the extended releasing incisions within the mucosa. This can affect oral hygiene procedures that are difficult in the case of shallow oral vestibulum and may cause a relapse of the treatment.³²

Statistically significant differences were observed between two groups in the WKT (p = 0) (this agrees with another study⁵), TKT (p = 0), VD (p = 0), change the position of MGJ (p = 0), and RC (0.050) measurements at the end of follow-up.

Differences in treatment results with the previous studies might be associated with differences in case selection, inclusion criteria including baseline recession depth, the amount of keratinized tissue, flap thickness, single-tooth or multiple teeth, technique design,^6,17 using no suture for SCPF,^5,15 using microsurgery,⁴ adhesive application,^4,16,31 EDTA used for root surface biomodification,⁴ and differences in the follow-up period. In addition to that, there was a difference in the way of measuring the parameters, i.e., we used the digital caliper with 0.01 mm precision with spreader and rubber stop to attain the most possible precise measurements.

When looking into the healing pattern for CAF, in the first week, the wound exhibited minimal color alteration with edema and erythema. The vertical incisions were clearly distinguishable. In the second week, edema and erythematous aspect progressively diminished, and these findings are similar to those presented by Huang et al.⁹ At the 3-month evaluation point (Fig. 2E), the color, texture, and contour became similar to the adjacent soft tissues and minimal scarring was noticeable in releasing incisions. However, the healing in the SCPF followed different stages, because the connective tissue remained exposed after displacing the tissue toward the coronal direction. We also noticed reddish granulation tissue formation and edema at the 1-week evaluation point. The intensity of these signs decreased gradually in the second week. After 3 months (Fig. 1E), the tissue was normal. However, a distinguished semilunar white scar was noticed in the incision site in some cases and these results resemble those of previous studies.^5,31

In the SCPF group, an improvement was observed in wound healing throughout the first, second, and fourth week after surgery. A notable statistically significant difference between the two procedures was seen in the WHI for only the first week after surgery (p = 0.03).

For esthetic evaluation was achieved using both subjective and objective measurements. The objective measurement estimated that the RES was 7.50 ± 1.7 in the SCPF group. Four teeth achieved a total score (25%), and when compared with a study that used a new modification, the RCS was lower than that reported in our study (6.8 ± 1.3). The subjective evaluation revealed that 13 patients were satisfied with the final esthetic appearance with “excellent” rating by 81.3%; however, Bittencourt et al.³¹ reported “excellent” rating by 9 of the 17 patients, “good” by 7 patients, and “sufficient” by 1 patient. When asked about the preferred procedure, seven patients selected this technique (43.8%) and the most frequent reason for preferring this technique was “more beautiful” (31.3%). These results agree with those reported by previous studies.^16,31

Although the RES score was 7.25 ± 1.7 for the CAF group and only two teeth achieved a total score (12.5%). The patients were satisfied with the esthetic result after 3 months and 56.3% gave it an “excellent” rating. Eight patients (50%) preferred this treatment and the most frequent reason for preferring this technique was “more beautiful” (7 patients 43.8%). Cairo et al.¹⁰ estimated the RES for CAF and found the RC ranged between 50% and 100% and the RES score ranged between 6 and 10. However, it was 6.7 ± 1.5 in a previous study.²⁹

The lesser value of RCS for CAF in comparison to SCPF may be explained by the fact that the SCPF does not interfere with papillae in its design,³ while CAF¹¹ relies on incisions at linear angles of the tooth by de-epithelizing the papillae. In addition to the keloid formation along the vertical releasing incisions in some cases was responsible for decreasing the esthetic evaluation made by the periodontist and the patient.

Regarding root sensitivity, it reduced from 87.6% at baseline to 18.7% (patients reported without root sensitivity by 81.3%) after 3 months for both groups. On the contrary to the present study, Bittencourt et al.³¹ reported no sensitivity at the end of follow-up that may be explained by higher RC%. However, the sensitivity improved between baseline and at the end point of the study, which was consistent with previous studies.^16,29

No postoperative pain was reported among 75%, 81.3%, and 93.8% of the patients after 24, 48, and 72 hours, respectively. Of the 16, 9 (56.3%) patients did not take analgesic pills in the SCPF group. This differs with another study³¹ that reported no pain during the healing period, which may be due to the gentle manipulation of tissues by using microsurgery.

For the CAF group, patients reported no postoperative pain by 62.5% and 68.8% after 24 and 48 hours, respectively. After 72 hours, the percentage was 75%. Of the 16, 9 (56.3%) patients needed analgesics. The stronger postoperative pain in the CAF group compared with the SCPF group can be explained by extending the releasing incisions within the mucosa and edema during the healing process.

Although significant improvements were achieved using TTC biomodification and anchorage sutures, this study has a series of methodological limitations. First, a small sample size of the study and the short follow-up period may affect the reproducibility of the results. Alas, further studies with a larger sample size are needed in order to evaluate the long-term stability of the positive results.

CONCLUSION

Based on the results of the present study, we found that both procedures with the TTC biomodification of the root surface and anchorage sutures were effective, predicted surgical techniques, and provided satisfactory results in the treatment of gingival recession Miller’s class I for the patient and the periodontist.

In the semilunar CAF, a slightly higher proportion of the RC is achieved compared to the procedure of conventional CAF. Also, the RES and proportions of the patient’s opinion, esthetic, and preference are higher for SCPF than for CAF.

A greater WKT and TKT can be expected with the SCPF in comparison with the CAF. The SCPF produced an increase in the depth of the vestibule. So in cases of a shallow oral vestibulum and a gingival recession, it may be contraindicated to use CAF and preferable to use SCPF.

REGISTRATION

The study protocol was registered on ClinicalTrials.gov, with Registration number: NCT03391947 https://clinicaltrials.gov/ct2/show/NCT03391947?cond=semilunarandrank=1.

REFERENCES

1. Cortellini P. Minimally invasive surgical techniques in periodontal regeneration. J Evid Based Dent Pract 2012;12(3 Suppl):89–100. DOI: 10.1016/S1532-3382(12)70021-0.

2. Cairo F, Pagliaro U, Nieri M. Treatment of gingival recession with coronally advanced flap procedures: a systematic review. J Clin Periodontol 2008;35(8 Suppl):136–162. DOI: 10.1111/j.1600-051X.2008.01267.x.

3. Tarnow DP. Semilunar coronally repositioned flap. J Clin Periodontol 1986;13(3):182–185. DOI: 10.1111/j.1600-051X.1986.tb01456.x.

4. Bittencourt S, Ribeiro ÉDP, Sallum EA, et al. Root surface biomodification with EDTA for the treatment of gingival recession with a semilunar coronally repositioned flap. J Periodontol 2007;78(9):1695–1701. DOI: 10.1902/jop.2007.060507.

5. Santana RB, Mattos CML, Dibart S. A clinical comparison of two flap designs for coronal advancement of the gingival margin: semilunar versus coronally advanced flap. J Clin Periodontol 2010;37(7):651–658. DOI: 10.1111/j.1600-051X.2010.01582.x.

6. Rana SRL, Shrestha SM, Pradhan A. Comparison of coronally advanced flap with semilunar coronally repositioned flap with sutures for the treatment of gingival recession. Med J Shree Birendra Hosp 2016;14(2):15–21. DOI: 10.3126/mjsbh.v14i2.13559.

7. Turesky S, Gilmore ND, Glickman I. Reduced plaque formation by the chloromethyl analogue of victamine C. J Periodontol 2010;41(1):41–43. DOI: 10.1902/jop.1970.41.1.41.

8. Mühlemann HR, Son S. Gingival sulcus bleeding--a leading symptom in initial gingivitis. Helv Odontol Acta 1971;15(2):107–113.

9. Huang L-H, Neiva REF, Wang H-L. Factors affecting the outcomes of coronally advanced flap root coverage procedure. J Periodontol 2005;76(10):1729–1734. DOI: 10.1902/jop.2005.76.10.1729.

10. Cairo F, Rotundo R, Miller PD, et al. Root coverage esthetic score: a system to evaluate the esthetic outcome of the treatment of gingival recession through evaluation of clinical cases. J Periodontol 2009;80(4):705–710. DOI: 10.1902/jop.2009.080565.

11. Allen EP1 MPJ. Coronal positioning of existing gingiva: short term results in the treatment of shallow marginal tissue recession. J Periodontol 1989;60(6):316–319. DOI: 10.1902/jop.1989.60.6.316.

12. Woodyard JG, Greenwell H, Hill M, et al. The clinical effect of acellular dermal matrix on gingival thickness and root coverage compared to coronally positioned flap alone. J Periodontol 2004;75(1):44–56. DOI: 10.1902/jop.2004.75.1.44.

13. George J, Prabhuji MLV, Shaeesta K, et al. Fibrin glue application in conjunction with tetracycline hydrochloride root conditioning and semilunar coronally repositioned flap in the treatment of gingival recession. J Indian Soc Periodontol 2011;15(1):74–79. DOI: 10.4103/0972-124X.82259.

14. Bhandari R, Uppal R, Kahlon K. Comparison of semilunar coronally advanced flap alone and in combination with button technique in the treatment of Miller’s class I and II gingival recessions: a pilot study. Indian J Dent Res 2015;26(6):609–612. DOI: 10.4103/0970-9290.176925.

15. Moka LR, Boyapati R, Mutthineni RB, et al. Comparision of coronally advanced and semilunar coronally repositioned flap for the treatment of gingival recession. J Clin Diagnostic Res 2014;8(6):ZC04–ZC08.

16. França-Grohmann IL, Sangiorgio JPM, Bueno MR, et al. Does enamel matrix derivative application improve clinical outcomes after semilunar flap surgery? A randomized clinical trial. Clin Oral Investig 2019;23(2):879–887. DOI: 10.1007/s00784-018-2506-y.

17. Santamaria M, Saito M, Mathias I, et al. A novel modification of semilunar coronally advanced flap for the treatment of gingival recession: case series. Int J Periodontics Restorative Dent 2017;37(2):235–240. DOI: 10.11607/prd.2647.

18. Baldi C, Pini-Prato G, Pagliaro U, et al. Coronally advanced flap procedure for root coverage. Is flap thickness a relevant predictor to achieve root coverage? A 19-case series. J Periodontol 1999;70(9):1077–1084. DOI: 10.1902/jop.1999.70.9.1077.

19. Pini Prato G, Pagliaro U, Baldi C, et al. Coronally advanced flap procedure for root coverage. Flap with tension versus flap without tension: a randomized controlled clinical study. J Periodontol 2000;71(2):188–201. DOI: 10.1902/jop.2000.71.2.188.

20. Saletta D, Prato GP, Pagliaro U, et al. Coronally advanced flap procedure: is the interdental papilla a prognostic factor for root coverage? J Periodontol 2001;72(6):760–766. DOI: 10.1902/jop.2001.72.6.760.

21. Santana RB, Furtado MB, Mattos CML, et al. Clinical evaluation of single-stage advanced versus rotated flaps in the treatment of gingival recessions. J Periodontol 2010;81(4):485–492. DOI: 10.1902/jop.2010.090237.

22. Jepsen K, Jepsen S, Zucchelli G, et al. Treatment of gingival recession defects with a coronally advanced flap and a xenogeneic collagen matrix: a multicenter randomized clinical trial. J Clin Periodontol 2013;40(1):82–89. DOI: 10.1111/jcpe.12019.

23. Nedelec B, Ghahary A, Scott PG, et al. Control of wound contraction. Basic and clinical features. [Review] [134 refs]. Hand Clin 2000;16(2):289–302.

24. Werfully S, Areibi G, Toner M, et al. Tensile strength, histological and immunohistochemical observations of periodontal wound healing in the dog. J Periodontal Res 2002;37(5):366–374. DOI: 10.1034/j.1600-0765.2002.01375.x.

25. Santos FR, Storrer CLM, Cunha EJ, et al. Comparison of conventional and semilunar coronally positioned flap techniques for root coverage in teeth with cervical abrasion restored with pink resin. Clin Cosmet Investig Dent 2017;9:7–11. DOI: 10.2147/CCIDE.S119040.

26. Lang NP, Lindhe J, Clinical periodontology and implant dentistry. Volume 1: Basic concepts; 2015.

27. Pini-Prato G, Baldi C, Pagliaro U, et al. Coronally advanced flap procedure for root coverage. treatment of root surface: root planing versus polishing. J Periodontol 1999;70(9):1064–1076. DOI: 10.1902/jop.1999.70.9.1064.

28. Santamaria MP, Suaid FF, Casati MZ, et al. Coronally positioned flap plus resin-modified glass ionomer restoration for the treatment of gingival recession associated with non-carious cervical lesions: a randomized controlled clinical trial. J Periodontol 2008;79(4):621–628. DOI: 10.1902/jop.2008.070285.

29. Cairo F, Cortellini P, Tonetti M, et al. Coronally advanced flap with and without connective tissue graft for the treatment of single maxillary gingival recession with loss of inter-dental attachment. A randomized controlled clinical trial. J Clin Periodontol 2012;39(8):760–768. DOI: 10.1111/j.1600-051X.2012.01903.x.

30. Buggapati L, Chava V. Effect of combination of ethylenediaminetetraacetic acid + tetracycline with coronally positioned flap in the treatment of gingival recession: a clinical study. J Indian Soc Periodontol 2016;20(1):57–62. DOI: 10.4103/0972-124X.168488.

31. Bittencourt S, Del Peloso Ribeiro É, Sallum EA, et al. Comparative 6-month clinical study of a semilunar coronally positioned flap and subepithelial connective tissue graft for the treatment of gingival recession. J Periodontol 2006;77(2):174–181. DOI: 10.1902/jop.2006.050114.

32. Müller H-P, Stahl M, Eger T. Root coverage employing an envelope technique or guided tissue regeneration with a bioabsorbable membrane. J Periodontol 1999;70(7):743–751. DOI: 10.1902/jop.1999.70.7.743.

33. Nassar CA, Da Silva WAD, Tonet K, et al. Comparing semilunar coronally positioned flap to standard coronally positioned flap using periodontal clinical parameters. Gen Dent 2014;62(2):47–49.