Morphometric, Densitometric, and Mechanical Properties of Maxillary Teeth in 5-Month-Old Polish Merino Sheep

Abstract

This study was performed to determine morphological, densitometric, mechanical, and elemental characteristics of maxillary teeth in 5-month-old Polish Merino sheep. The total tooth volume (Tvol) was determined using quantitative computed tomography. Micro-computed tomography was used to determine the total enamel volume (Evol), volumetric enamel mineral density, total dentine volume (Dvol), volumetric dentine mineral density, and total tooth enamel and dentine volume (EDvol). Compression testing was used to determine the ultimate force of teeth. Microhardness of enamel and dentine was evaluated using Vicker’s test. Elemental analysis of enamel and dentine was performed using a scanning electron microscopy technique. Tooth weight, length, Tvol, Evol, Dvol, and EDvol increased consequently from the lowest values for p², then for p³ and p⁴, to the highest values obtained for M¹ (all p < 0.05). Ultimate force reached the lowest value for p² compared with the other teeth (p < 0.05). The comparison of left and right teeth did not reveal significant differences for all the evaluated parameters (p > 0.05). Volumetric mineral density, calcium and phosphorus content, and microhardness were higher in enamel than in dentine, while the opposite results were obtained for magnesium and oxygen (all p < 0.05). Significantly higher enamel microhardness was found in mandibular i₁ compared with maxillary and mandibular premolars (p < 0.05). The elaborated experimental model of the determination of maxillary deciduous teeth traits may serve for further studies on the effects of physiological, pathological, environmental, nutritional, pharmacological, and toxicological factors affecting tooth development and mineralized tissue properties.