Pre-restorative crown lengthening surgery: influence of restorative treatment timing on clinical outcomes-a pilot study

Abstract

Objectives: Aim of this study was to assess the influence of restorative treatment timing on the periodontal, patient and operator-reported outcomes following crown lengthening surgery (CLS).

Materials and methods: Eighteen study participants requiring CLS were divided into two groups based on prosthetic rehabilitation timing (6 or 14 weeks postoperatively). Clinical parameters were recorded around treated and neighboring teeth before and after surgery, 6 and 14 weeks postoperatively, at prosthesis delivery, and three and six months after. Soft tissue and radiographic bone changes were evaluated. Patients assessed their perception of the procedure by means of a questionnaire. The final treatment outcome was rated by both patients and prosthodontists.

Results: CLS resulted in statistically significant and stable apical displacement of the gingival margin, at both treated and adjacent sites. Plaque and bleeding scores remained low throughout. No statistically significant differences were observed between groups for any clinical or radiographic parameter examined. Healing was uneventful and treatment outcome was satisfying for both patients and prosthodontists, without statistically significant differences between groups.

Conclusions: The present study has been characterized as pilot, because it was not possible to reach the sample size indicated by the a priori power analysis. CLS is an effective pre-prosthetic procedure as long as it is performed under a certain surgical protocol which predicts for at least a 3 mm distance between bone crest and the flap margin at suturing. Within the limitations of this study, six weeks after surgery may be an adequate healing time for the onset of prosthetic restoration.

Clinical relevance: Crown lengthening surgery is commonly performed in daily clinical practice with the aim to restore teeth with short clinical crowns. Based on periodontal, patient and operator-reported criteria, 6 weeks after CLS may be adequate healing time before the onset of prosthetic restoration.

Trial registration: ClinicalTrials.gov Identifier: NCT03947658, 13/05/2019, retrospectively registered.

Keywords: (MeSH terms): Attitude of health personnel; Crown lengthening; Dental prosthesis; Patient-reported outcome measures; Time factors; Tooth crown.