Comparative Analysis of Root Dentin Morphology and Structure of Human Versus Bovine Primary Teeth

This study evaluated the structural and morphological differences between human and bovine primary root canals. Primary human maxillary central incisors (H) (n = 9) and primary bovine incisors (B) (n = 9) were selected. The roots were sectioned in the vestibular-lingual direction, planed and delimited in cervical, middle, and apical thirds. Tubule density (number of tubules per mm(2)) and diameter were analyzed by scanning electron microscopy (1,000 and 5,000x) using Image J 1.47 software. Data were submitted to two-way repeated measures ANOVA and Tukey tests (alpha = 0.05). The highest tubule density was observed for B (28.527 +/- 1.717 mm(2)) compared with H (15.931 +/- 0.170 mm2) (p<0.01). Regarding root thirds, the cervical third presented a greater tubule density (26.417 +/- 11.654 mm(2)) than the apical third (17.999 +/- 5.873 mm(2)). The diameter of the dentin tubules was not different for cervical (3.50 +/- 0.08 mu m), middle (3.45 +/- 0.30 mu m) and apical thirds (3.42 +/- 0.33 mu m) and substrate (H-3.29 +/- 0.14 mu m; B-3.63 +/- 0.06 mu m). It could be concluded that: (1) the radicular dentin structure of human and bovine primary teeth and root thirds differ in terms of the tubule density; (2) the radicular dentin morphology of human and bovine primary teeth and root thirds are similar in terms of the diameter of the dentin tubules.