Comparative analysis of dental erosion on natural buccal and occlusal enamel surfaces

To compare the susceptibility of natural enamel on buccal and occlusal surfaces to erosion by assessing step-height changes.

Twenty enamel samples were obtained from caries-free, unerupted human molars. Paired buccal and occlusal specimens (n = 10 each) were prepared from the same teeth and mounted in custom-designed cobalt-chrome moulds and randomly assigned to the groups. Samples underwent acid challenges using 0.3 wt. % citric acid (pH 2.7) for cumulative durations of 10, 20, 40, and 60 min. Surface changes were measured using white light profilometry and scanning electron microscopy (SEM) used to examine the ultrastructural differences between paired surfaces.

Mean step-height loss for buccal surfaces at 10, 20, 40, and 60 min was 5.36 ± 4.80 µm, 8.67 ± 6.05 µm, 18.69 ± 10.19 µm, and 25.50 ± 11.72 µm respectively. Occlusal surfaces showed losses of 6.30 ± 2.58 µm, 9.18 ± 4.17 µm, 25.92 ± 6.38 µm, and 33.84 ± 11.48 µm at corresponding timepoints. Despite consistently higher mean step-height loss in occlusal surfaces, differences were not statistically significant (p = 0.055). Linear regression analysis revealed significant positive slopes for both surfaces (p < 0.0001) with no significant difference between slopes (p = 0.06).

Natural buccal and occlusal enamel surfaces showed similar susceptibility to erosion despite ultrastructural differences, indicating clinical erosion patterns may result more from environmental factors than inherent surface properties.

This study introduces a novel methodology for analysing tooth wear on natural enamel surfaces using a custom-built mould as a reference. The findings suggest that buccal and occlusal surfaces exhibit similar erosion susceptibility in vitro, despite their varying ultrastructural characteristics. This implies that observed clinical differences in erosion patterns may be influenced more by environmental factors than inherent surface properties.