Fracture strength of teeth with access cavity preparation with operating microscope or on buccal surfaces

Yohanna Campos D’Amico,Alexandre Kowalczuck,Vânia Portela Ditzel Westphalen,Everdan Carneiro,Ulisses Xavier Da Silva Neto

doi:10.14295/bds.2019.v22i1.1655

Abstract

Objective: The present study assessed the fracture strength of teeth subjected to endodontic access cavity preparation on buccal surfaces, or with the aid of operating microscopy when compared to the conventional technique. Material and methods: Sixty mandibular incisors were split into four groups (n=15): conventional access cavity preparation (CCP); conservative (C); buccal surface (BS); and control. The canals were prepared and filled and the cavities were restored. A static compressive strength test was conducted until crown fracture. The force data were compiled and assessed statistically. Kolmogorov-Smirnov and Shapiro-Wilk tests were performed to assess normality, Levene’s test to assess variance homogeneity, the one-way ANOVA to compare fracture strength in the assessed groups. Tukey’s HSD test was used to determine whether the differences in the means were significant between the groups.Results: The experimental groups did not show any statistically significant differences in mean fracture strength (CCP = 585.65 N±107.64 N)(BS = 530.52 N±129.35 N) (C = 517.83 N±114.68 N). Conclusion: Therefore, the selection of surface or size of access cavity proposed did not influence the fracture strength of mandibular incisors when compared to conventional cavity preparation. KeywordsDental pulp cavity; Dental stress analysis; Root canal therapy.

Highlights

The possibility of straight and direct access to root canal content is one of the principles of endodontic access cavity preparation [1,2]
The present study assessed the fracture strength of teeth subjected to endodontic access cavity preparation on buccal surfaces, or with the aid of operating microscopy when compared to the conventional technique
The specimens were centrally placed in the Polyvinyl chloride (PVC) cylinders containing the resin, and each specimen was placed at two millimeters from the root exposed, i.e., without being covered by the resin

Summary

INTRODUCTION

The possibility of straight and direct access to root canal content is one of the principles of endodontic access cavity preparation [1,2]. The present study assessed the fracture strength of teeth subjected to endodontic access cavity preparation on buccal surfaces, or with the aid of operating microscopy when compared to the conventional technique. Was prepared in a conventional fashion, i.e., on the lingual surface at two millimetres from the cingulum to the incisal edge. Trepanation was performed with round-ended tapered diamond burs (1011 – KG Sorensen, São Paulo, Brazil), and the cavity was abraded into a triangular shape, with the base oriented towards the incisal edge. The lingual dentinal deposition was abraded with diamond bur #3080 (Figure 1A). The access cavity in the conservative (C) group was prepared with a clinical microscope, exposing the coronal chamber wide enough for insertion of a WaveOne Gold Primary (Dentsply Indústria e Comércio Ltda, Rio de Janeiro, Brazil) reciprocating instrument (Figure 1C). The control group was not subjected to any intervention (Figure 1D)

Material and Methods

Results

Discussion