Relationship between external and internal structures in deciduous teeth: a multidisciplinary study

Aim The different dental structures of deciduous teeth have always been regarded with great interest in endodontics and restorative dentistry. Nevertheless, there are still few investigations on the morphology of deciduous teeth compared to the permanent ones, due to the difficulty in obtaining sound deciduous teeth suitable for measurement. The aim of this research is to evaluate and compare the internal and external structures of deciduous teeth from completely preserved hominid findings, using X-ray and micro-CT examination.Study Design Twenty-two archaeological tooth finds were collected and analysed. Samples were divided into two subgroups according to gender and arch region.Methods Samples were photographed using a digital camera and were then analysed by X-ray and micro-CT. Different parameters of external and internal structures were calculated to obtain a normalisation coefficient, called the P-factor.Statistics The statistical analysis was performed using one-way analysis of variance (ANOVA) and Holm-Sidak multiple comparison test, setting the significance at p <0.05.Results The P-factors obtained show a similar result (0.25 +/- 0.05), and no significant differences were found between all calculated parameters (p>0.05).Conclusion There is a constant correlation between external and internal structure, regardless of gender, type, shape or arch sector.