Estimated Time of Biomineralization in Developing Rat Incisors

Abstract

The aim of this study was to estimate time of biomineralization in developmental stages of rat lower incisors. Eruption length was measured. Four stages of incisor development were identified on histologic and microscopic computerized tomography (micro-CT) sections: (1) preodontoblast, (2) dentin matrix secretion, (3) enamel matrix secretion, and (4) enamel calcification. The overall eruption rate of the rat lower incisor was 600 ± 70 μm/day (mean ± SD; n = 12). The length of the enamel secretion was 4.59 ± 0.75 mm in histologic section, was 3.64 ± 0.63 mm in radiographic section, which converts to 180.4 ± 30.0 hours, 145 ± 25 hours respectively (n = 24). These findings suggested that the four biomineralizing developmental stages of the rat incisor took only several days. The significance of this animal study was to provide understanding for the rapid biomineralization process of developing rat tooth germ by analysis of tooth forming period.