Periodontal outcomes and digital volumetric variation following restorations using the biologically oriented preparation technique (BOPT)

Abstract

Statement of problem: Gingival recession is one of the most common complications following prosthetic treatment. However, scientific evidence addressing this periodontal behavior in patients treated with the biologically oriented preparation technique (BOPT) is lacking.

Purpose: The purpose of this prospective clinical trial was to evaluate the periodontal outcomes on teeth prepared with the BOPT over a 2-year follow-up period, assessed by using digital technologies.

Material and methods: Sixty-four teeth requiring retreatment because of unsatisfactory prosthetic restorations were prepared to receive complete coverage zirconia crowns by using the BOPT. Periodontal parameters, including the gingival index (GI), plaque index (PI), probing depth (PD), gingival margin stability, biological and mechanical complications, and gingival thickness were recorded. An initial digital scan was made, generating a standard tessellation language (STL) file, and a second digital scan was made after treatment. The digital files were imported into a software program and superimposed to create a merged file which was used to evaluate changes in gingival thickness. Generalized estimating equations (GEEs) were used for inferential analysis, accounting for the hierarchical patient-tooth structure and assessing temporal changes by using the Wald chi-squared test (α=.05).

Results: A total of 64 teeth restored with single-unit complete coverage zirconia crowns were analyzed in the second year of follow-up. The gains in buccal and palatal gingival thickness were statistically significant (P<.001). However, changes in gingival and plaque indices were not statistically significant (P>.05). No crowns exhibited gingival recession, and probing depths remained within the 0- to 3-mm range. Two crowns developed pulpitis during the first year, representing a mechanical and biological failure rate of 3.1%.

Conclusions: The clinical follow-up of the teeth restored with the BOPT indicated good periodontal health based on the stability and the positive results of the clinically analyzed parameters.