Enamel Thickness in Primary Teeth

Objective: The aim of this study was to determine the enamel thickness of all primary teeth in both maxilla and mandible. Study Design: An in vitro study was performed with fifty primary teeth including five each of central and lateral incisor, canine, first and second primary molars in both maxillary and mandibular region. Samples were mounted on wax sheets and scanned using a 64-slice CT scanner, which were then 3D reconstructed. Three serial slices were obtained from the middle of the coronal portion of each tooth. Volume rendering was done to differentiate three distinct zones of enamel, dentin and the pulp from each slice. A box was constructed touching the borders of the image on all the surfaces and the mid-point of each side was taken to measure the enamel thickness. Results: Tests used were ANOVA, Post-hoc Tukey's test and student's paired t-test. Enamel thickness was not the same on all the sides. Intergroup comparisons between maxillary anterior and posterior teeth showed difference in enamel thickness. On comparing the mandibular anterior and posterior teeth, the posteriors showed a greater value of enamel thickness on all the sides.(p<0.05). Conclusion: Primary enamel does not follow the same thickness patterns on all sides. It is also different in each primary tooth. There was an increase in enamel thickness in posterior teeth on comparison to their anterior counterparts in both maxilla and mandible. Enamel thickness was more on the distal aspect compared to mesial in all samples.

Enamel thickness, Primary teeth, 64-slice CT scanner, Volume rendering, Tests, Intergroup comparisons

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