Avaliação laboratorial do cemento dentário por meio da tomografia por coerência óptica

Abstract

The cementum is disposed on the dental root surface and presents continuous deposition under physiological condition with different responses to periodontal and occlusal changes, widely used for forensic purposes. The Optical Coherence Tomography (OCT), is a non-invasive, nonionizing method, with the possibility of in vivo and in vitro application. Objective: to quantify and qualify the structure of the cementum through OCT according to dental group, faces, and age group, in addition the correlation between age and cementum thickness was also analyzed. Method: 53 teeth were scanned using the Callisto OCT model (ThorlabsInc, New Jersey, USA), using a superluminescent diode (930 nm) bandwidth of 100 nm and maximum output power of 3 mW. The image analysis were performed using the ImageJ software and the data were analyzed using the IBM SPSS Statistics program (Version 20.0, IBM SPPS). Comparisons of cement thickness and qualitative variables between unrelated groups were performed using the Kruskal Wallis test (p <0,05); Friedman's test (p <0,05) was performed among groups that maintained a link, and Bonferroni's post hoc test when a significant difference was identified. To analyze the correlation between thickness by thirds and age, the Spearmann Correlation Test (p <0,01) was performed. Results: A greater thickness was observed in the thirds in an apical section; with difference in thickness between the dental groups (p <0,05) in the middle and apical thirds (p <0.05); between the faces there was a difference only in the middle third between the buccal and mesial faces (p <0,05); there was an increase in thickness as a result of increasing age with a strong correlation between thickness of the middle thirds (r = 0.712; p <0,01) and apical (r = 0.527; p <0,01) in the anterior dental group. There is a predominance of changes in translucency in the middle and apical thirds, as well as the presence of spots in the apical third regardless of age group, face, and dental groups; as for uniformity, the apical third also showed greater changes in all groups analyzed. Conclusion: Through OCT it was possible to measure the thickness of the cementum, noting also qualitative differences in relation to the thirds and dental group, in addition to differentiation in related age with a greater correlation of age in anterior teeth.