Background: Various techniques have been suggested to quantitatively assess tooth wear; most have limited clinical application. The first aim of this in vitro study was to estimate the residual enamel thickness of teeth with various degrees of occlusal wear using quantitative light-induced fluorescence (QLF). The second aim was to identify relationships between the fluorescence parameters of QLF and the conventional tooth wear index (TWI) system. Methods: Sixty-nine extracted permanent premolars and molars with initial stages of tooth wear (TWI score 1a-2: enamel wear to dentin exposure) were used. Two blinded and trained examiners participated in evaluation procedures. Occlusal QLF-digital (QLF-D) images were acquired for selecting area of interest (AOI) and calculating fluorescence for occlusal tooth wear (ΔF wear ) of the AOI by the first examiner. Each specimen was cross-sectioned in the buccal-lingual direction. Enamel thickness from images obtained by stereomicroscopy and TWI of each sample was determined by the second examiner. Spearman correlation was used to determine the relationship of ΔF wear with enamel thickness and TWI. ΔF wear values were compared between histological scores with the Mann-Whitney U test. Results: Seventy-six AOIs were analyzed. As enamel thickness decreased, ΔF wear values significantly increased and strongly correlated with enamel thickness (Spearman rho = -0.825, P < 0.001). There were significant differences in ΔF wear values among TWI scores (P < 0.001); ΔF wear strongly correlated with TWI (Spearman rho = 0.753, P < 0.001). Conclusions: ΔF wear values, which denote fluorescence difference by using QLF, showed a strong correlation with residual enamel thickness and tooth wear severity.
Bibliographical noteFunding Information:
Inspektor Research Systems BV provided the salary for author EdJdJ, but did not have any additional role in the study design, data collection, analysis, decision to publish, or preparation of the manuscript. EdJdJ’s involvement in this research was under the auspices of his status as adjunct professor at Yonsei University College of Dentistry supported by BK21 PLUS Project. The specific role of EdJdJ was to provide his expertise regarding the fluorescence technology. This does not alter the author’s adherence to the policies of the Journal of Biomedical Optics on sharing data and materials. EdJdJ holds several patents with respect to QLF technology. The remaining authors declared no conflicts of interest.
This study was supported by a grant from the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through High Value-added Food Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) ( 316071031HD020 ).
All Science Journal Classification (ASJC) codes
- Pharmacology (medical)