title: Open-flap versus flapless esthetic crown lengthening: 12-month clinical outcomes of a randomized controlled clinical trial.
abstract: BACKGROUND
  Excessive gingival display (EGD) has a negative impact on a pleasant smile. Minimally invasive therapeutic modalities have become the standard treatment in many dentistry fields. Therefore, the aim of this study is to compare the clinical outcomes of open-flap (OF) and minimally invasive flapless (FL) esthetic crown lengthening (ECL) for the treatment of EGD.
  
  
  METHODS
  A split-mouth randomized controlled trial was conducted in 28 patients presenting with EGD. Contralateral quadrants received ECL using OF or FL techniques. Clinical parameters were evaluated at baseline and 3, 6, and 12 months post-surgery. The local levels of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) were assessed by enzyme-linked immunosorbent assay at baseline and 3 months. Patients' perceptions regarding morbidity and esthetic appearance were also evaluated. Periodontal tissue dimensions were obtained by computed tomography at baseline and correlated with the changes in the gingival margin (GM).
  
  
  RESULTS
  Patients reported low morbidity and high satisfaction with esthetic appearance for both procedures (P >0.05). RANKL and OPG concentrations were increased in the OF group at 3 months (P <0.05). Probing depths were reduced for both groups at all time points, compared with baseline (P <0.05). There were no differences between groups for GM reduction at any time point (P >0.05).
  
  
  CONCLUSIONS
  FL and OF surgeries produced stable and similar clinical results up to 12 months. FL ECL may be a predictable alternative approach for the treatment of EGD.
authors.affiliation: Department of Periodontology, Dental Research Division, Guarulhos University, Guarulhos, São Paulo, Brazil.
authors.forename: Fernanda V
authors.initials: FV
authors.lastname: Ribeiro
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Hirata
authors.forename: André F
authors.initials: AF
authors.lastname: Reis
authors.forename: Vanessa R
authors.initials: VR
authors.lastname: Santos
authors.forename: Tamires S
authors.initials: TS
authors.lastname: Miranda
authors.forename: Marcelo
authors.initials: M
authors.lastname: Faveri
authors.forename: Poliana M
authors.initials: PM
authors.lastname: Duarte
mesh_terms: D000328:Adult; D000541:Alveolectomy / Q000379:methods; D001294:Attitude to Health; D054893:Cone-Beam Computed Tomography / Q000379:methods; D016556:Crown Lengthening / Q000379:methods*; D003774:Dental Plaque Index; D004955:Esthetics, Dental; D005260:Female; D005500:Follow-Up Studies; D005881:Gingiva / Q000473:pathology; D005890:Gingivectomy / Q000379:methods; D006801:Humans; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D061646:Operative Time; D053244:Osteoprotegerin / Q000032:analysis; D017060:Patient Satisfaction; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000145:classification / Q000601:surgery; D011183:Postoperative Complications; D053245:RANK Ligand / Q000032:analysis; D016745:Root Planing / Q000379:methods; D013524:Surgical Flaps / Q000601:surgery*; D019237:Tooth Cervix / Q000473:pathology; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D053244:Osteoprotegerin; D053245:RANK Ligand; C505688:TNFSF11 protein, human