Related Experiment Video
Updated: Oct 15, 2025

Mimicking and Measuring Occlusal Erosive Tooth Wear with the "Rub&Roll" and Non-contact Profilometry
Published on: February 2, 2018
In situ Effect of CO2 Laser (9.3 μm) Irradiation Combined with AmF/NaF/SnCl2 Solution in Prevention and Control of
Juliane de Paula Tavares1, Camila Vieira da Silva2, Yael Engel2
1Department of Restorative Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil, juliane.tavares@alumni.usp.br.
Objectives:
This single-blind, controlled crossover in situ study aimed to evaluate the effect of CO2 laser (9.3 µm) irradiation combined with AmF/NaF/SnCl2 solution on prevention and control of erosive tooth wear (ETW) in human enamel.
Materials And Methods:
Two trial conditions were analyzed, condition 1 as ETW prevention (sound tooth surface) and condition 2 as ETW control (in vitro initial erosive lesion). The experiment was conducted in 2 phases, one with and one without exposure to AmF/NaF/SnCl2 solution. Hundred and ninety-two samples of human enamel (3 × 3 × 1 mm) were randomly divided into 4 experimental groups for each condition: C, without treatment (negative control); F, AmF/NaF/SnCl2 solution (positive control); L, CO2 laser irradiation; and L + F, CO2 laser + AmF/NaF/SnCl2 solution. Twelve volunteers used a removable device, each containing 8 samples per phase. Ex vivo erosive challenges (4 × 5 min/day) and rinsing protocol (1 × 30 s/day) were performed. The surface loss was determined using optical profilometer (n = 12 per group), and the surface morphology was observed with scanning electron microscopy (n = 3).
Results:
In condition 1, data were analyzed by one-way ANOVA and condition 2 by two-way repeated-measures ANOVA, both with Tukey post hoc tests (α = 5%). In condition 1, groups L (4.59 ± 2.95 µm) and L + F (1.58 ± 1.24 µm) showed significantly less surface loss in preventing ETW than groups C and F. In condition 2, in controlling the progression of ETW, L + F was the only group with no significant surface loss between initial erosive lesion (3.65 ± 0.16 µm) and after erosive challenge (4.99 ± 1.17 µm).
Conclusions:
CO2 9.3-µm laser application prevented and controlled ETW progression in human enamel, with greater efficiency when combined with AmF/NaF/SnCl2 solution application.

