# Assessment of minimally invasive caries excavation methods on caries-affected human dentin: A comparative analysis

## TL;DR

This study compares methods for removing tooth decay and finds that using a SmartPrep bur provides the strongest bond for dental fillings.

## Contribution

The study provides new empirical evidence on the impact of caries removal techniques on composite bond strength to dentin.

## Key findings

- SmartPrep bur showed the highest microtensile bond strength (33.31 MPa) compared to other methods.
- Air abrasion resulted in the lowest bond strength (15.74 MPa) and differed significantly from SmartPrep bur.
- Caries removal technique significantly affects composite bond strength to dentin.

## Abstract

Dental caries is a major global health issue, leading to tooth loss, infections, and even systemic complications. Modern dentistry favours minimally invasive caries removal, but its impact on the bond between composite and caries-affected dentin requires further study. The present in vitro analysis evaluated the microtensile bond strength (μTBS) of composite bonded to human dentin impacted by caries, after three caries removal methods: SmartPrep bur, chemo-mechanical removal, and air abrasion. The null hypothesis posited no significant difference in bond strength among the techniques.

Twenty-one extracted human molars with caries, but no pulpal involvement, were randomly allocated into three groups. Caries removal was performed using: 1) SmartPrep bur, 2) chemo-mechanical method using Papacarie® gel (Formula & Acao, Sao Paulo, Brazil) 3) air abrasion (AquaCare air-abrasion (Velopex, London, UK). Following caries removal, a two-step etch-and-rinse adhesive and composite restoration were placed. The test specimens from each group underwent microtensile bond strength testing utilizing a Universal Testing Machine, data were statistically analysed using one-way ANOVA and further examined with Tukey’s post hoc test (p<0.05).

Analysis revealed that SmartPrep bur demonstrated superior microtensile bond strength (33.31 ± 10.23 MPa), followed by chemo-mechanical removal (22.86 ± 11.61 MPa). Air abrasion yielded the lowest mean bond strength values (15.74 ± 2.99 MPa). The SmartPrep bur and air abrasion groups showed statistically significant differences (p = 0.012).

This study demonstrated that the caries removal technique significantly influences the bond strength of composite to caries-affected dentin. The SmartPrep bur achieved superior microtensile bond strength, suggesting potential clinical benefits. These results emphasize the importance of technique selection for achieving optimal restorative outcomes.

Key words:Caries, Dentin, adhesion, tooth.