Treatment of Teeth with Insufficient Clinical Crown. Part 1: One-Year Clinical Outcomes of a Minimally Invasive Crown-Lengthening Approach.

Abstract

This study describes a clinical strategy based on a flowchart developed to facilitate the treatment of teeth with a severely compromised clinical crown. A group of 168 teeth in 126 patients required periodontal surgery and received a minimally invasive crown-lengthening procedure with the aim to reach a minimal supracrestal tissue attachment width of 2.5 mm, including a free space between the cervical margin of the restoration and the bottom of the sulcus. Surgery was performed with the aid of an operating microscope and microsurgical instruments, trying to reduce bone surgery and invasiveness as much as possible. An average postsurgical radiographic bone resection of 1 ± 0.6 mm was measured. Endodontic treatment was necessary in 73 teeth, re-treatment in 51. Most of the teeth (124 in 94 patients) received a full crown, while the remaining 44 received a direct (24 teeth) or an indirect (20 teeth) reconstruction. Six teeth were orthodontically extruded before surgery. The 1-year average pocket depth at the treated units was 2.5 ± 0.5 mm, resulting in a reduction of 0.7 ± 0.9 mm compared to the preoperative measurement (P < .0001). Bleeding on probing was detected in 19 sites (11.3%) and was significantly reduced from the preoperative condition (57 sites, 33.9%). The distance between the apical margin of the restoration and the gingival margin was 0.2 ± 0.4 mm (range: 0 to 1 mm); clinical attachment level was 2.7 ± 0.6 mm. A clinical approach based on minimally invasive crown lengthening with minimal or no ostectomy and high-quality restorative dentistry resulted in healthy periodontal and dental condition of all the treated units at the 1-year follow-up.