METHODS: Twenty volumes of interests consisting of six anterior and fourteen posterior edentulous regions were obtained from human mandibular cadavers. A CBCT system with a resolution of 80 µm (3D Accuitomo 170, J. Morita, Kyoto, Japan) and a µCT system with a resolution of 35 µm (SkyScan 1173, Kontich, Belgium) were used to scan the mandibles. Three structural parameters namely, trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp) were analysed using CTAn software (v 1.11, SkyScan, Kontich, Belgium). For each system, the measurements obtained from anterior and posterior regions were tested using independent sample t-test. Subsequently, all measurements between systems were tested using paired t-test.
RESULTS: In CBCT, all parameters of the anterior and posterior mandible showed no significant differences (p > 0.05). However, µCT showed a significant different of Tb.Th (p = 0.023) between anterior and posterior region. Regardless of regions, the measurements obtained using both imaging systems were significantly different (p ≤ 0.021) for Tb.Th and Tb.N.
CONCLUSIONS: The current study demonstrated that only the variation of Tb.Th between anterior and posterior edentulous region of mandible can be detected using µCT. In addition, CBCT is less feasible than µCT in assessing trabecular bone microstructures at both regions.
MATERIALS AND METHODS: A total of 521 cranial MSCT datasets of Malaysian sub-adults (0-20 years old) consisting of Malay, Chinese, and Indian populations were analysed and constructed into three-dimensional (3D) cranial models using Mimics software version 21. Fourteen selected craniometric parameters were measured on the 3D models, adhering to the plane-to-plane protocol. All measurements were statistically analysed using discriminant function analysis.
RESULTS: Cranial measurements such as maximum cranial width, biasteronic width, and occipital chord showed significant differences among Malays, Chinese, and Indians. In addition, a high similarity of the measurements between Chinese and Malays compared to Indians and Malays and Chinese and Indians was demonstrated. The highest classification accuracy was obtained by the age group of 10-12 years old, with Indians achieving the highest accuracy (72.2%), followed by Chinese (71.8%) and Malays (58.3%). The accuracy percentages between the pooled-sex and male/female formulas were relatively similar.
CONCLUSIONS: This study demonstrated the presence of morphometric variations among the three different sub-adult populations in Malaysia using MSCT datasets.