Microstructure of Mineralized Tissues in Human Primary Teeth.

The aim of this study was to analyze the structural characteristics of the mineralized dental tissues - enamel, dentin and cementum - in primary teeth and to correlate the histological aspects observed in function of the dental type – single-rooted or multi-rooted. Method: Eighteen human primary noncarious teeth were sectioned in facial-lingual (single-rooted) and mesio-distal direction (multi-rooted). One to three samples from each tooth were obtained. The samples were prepared by the ground technique and analyzed under light microscopy at different magnifications. A quantitative and descriptive analysis of the morphology of the mineralized tissues was performed. Results: Spindles, tufts and lamellae were consistently observed mainly in the occlusal surface of the primary molars. The scalloped pattern of the dentinoenamel junction was not always present. The same was seen for zones of interglobular dentin. Dead tracts in dentin and tertiary dentin were observed mainly in single-rooted teeth below areas of dental attrition. Areas of cellular and acellular cementum were observed in the two dental types. Conclusions: Primary teeth have some structural peculiarities and these should be investigated concerning the clinical repercussion.

dental enamel; dentin; dental cementum; tooth, deciduous, primary.

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