# Evaluating the Proximal Contact Tightness in Direct or In-direct Restoration of Endodontically Treated Teeth: Randomized Clinical Trial

## TL;DR

This study compares resin composite and zirconia crown restorations for achieving proper tooth contact in root canal-treated teeth, finding both methods effective.

## Contribution

The study introduces a comparison of direct and indirect restoration methods using a novel quantitative force measurement device for proximal contact tightness.

## Key findings

- Both direct and indirect restorations achieved clinically acceptable proximal contact tightness.
- Quantitative measurements showed significantly higher contact tightness compared to natural teeth.
- There was a significant correlation between subjective and quantitative evaluation methods.

## Abstract

This study aimed to compare the efficacy of resin composite for establishing a proper proximal contact in comparison to digital work flow Zirconia for restoration of endodontically treated teeth (ETT).

Forty patients with posterior root canal treated teeth considering the inclusion and exclusion criteria were divided into two groups: half were restored by resin composite while the other received zirconia crown. Then, the proximal contact tightness (PCT) was measured via two methods: 1: VAS: the magnitude of felt PCT was recorded as a number between 0 to 10 (Visual Analogue Scale (VAS)). VAS direct and indirect as VAS-D, and VAS-I respectively. 2: Quantitative: using a custom-made force gage device to record the amount of force needed to pass a mounted dental floss through the proximal contact (Quantitative direct and indirect as Qn-D, and Qn-I respectively) those were compared with the PCT of natural teeth (NT). Data was compared with each other using Chi-square, Shapiro-Wilk, One Way ANOVA, Tukey Post Hoc, Linear regression, and Pearson tests (α= 0.05 in all tests).

There were no significant difference between direct and in-direct groups regarding either sex of the patients (P= 0.10), type of teeth (P= 0.32), or jaw side (P= 0.36). The VAS-D and VAS-I showed similar results in pairwise comparison (P= 0.21). Moreover, both the Qn-D and Qn-I showed significantly higher PCT comparing to NT (P= 0.45 and 0.0.0001 respectively) while the Qn-D and Qn-I were not distinguishable statistically (P= 0.23). Furthermore, significant correlation was observed between VAS and quantitative methods for evaluation of PCT (Pearson P value= 0.005).

Both the direct and in-direct restorations lead to clinically acceptable PCT, whilst indirect restorations showed slightly better results which was not statistically noticeable.

Key words:Composite resins, Zirconium oxide, Digital Technology.