The influence of tooth inclination on the quantity of tooth removal during access cavity preparation: an in vitro micro-CT study

Abstract

Aim: to assess the influence of tooth inclination (0° and 30°) on the access cavity preparation in vitro using Micro-CT. Methodology: Thirty-two identical 3D printed mandibular left 1st molar teeth (LL6) were mounted in dental jaw models at 0° and 30° inclination (n= 16 per group). Endodontic access was carried out by a right-handed specialist in Endodontics. The time to complete access cavity preparation was recorded. Video recordings were assessed to evaluate the impact of tooth inclination on the operator position. Access cavities were examined under a dental operating microscope to assess for iatrogenic damage. The quantity of remaining tooth material after access cavity preparation was calculated using Micro-CT. Data were analysed statistically using Shapiro–Wilk, Mann Whitney, and independent sample t-tests with a significance level of 5%. Results: The quantity of remaining tooth and the duration of access cavity preparation did not differ significantly between the 0° and 30° inclination groups (P > 0.05). No errors during access cavity preparation were detected. The operator position slightly shifted towards the 11 o’clock position and the operator’s wrist was more elevated during accessing inclined teeth. Conclusions: tooth inclination is not an influencing factor on the quantity of tooth removal, presence of errors, or time during access cavity in simulated LL6 prepared by an endodontic specialist. The operator position can be adjusted to compensate for the tooth inclination to prevent a detrimental outcome.