Measurement of anatomical structure of jaw bone trabecula with micro-CT and its accuracy evaluation

Objective: To measure the anatomic structures of the jaw and to discuss the accuracy of the method. Methods: The mandibular specimens were divided into ankle conylar group (3 specimens, regular trabecular architecture and mandibular body group (5 specimens, irregular trabecular architecture). Fifteen volumes of interests(VOI) were created in each group and the total of thirty were measured. The mean value and standard deviation of each parameter at each reconstruction voxel size were calculated. Repeated ANOVA test was used to determine whether the significant differences in the values existed between each parameter. Results: The structure model index (SM1) value in mandibular body group had significant difference(P<0.05) at all reconstruction voxel sizes compared with 18 μm group; but in condyle group, the reconstruction voxel size of 36 μm was not significant (P>0.05). The differences of trabecular thickness(Tb. Th), trabecular number(Tb. N) and trabecular seperation (Tb. Sp) values btween condyle and mandibular body groups were significant at all reconstruction voxel sizes(P< 0.05). In condyle group, except for Tb. Th, Tb. N, and Tb. Sp, the most parameter values were not significant at reconstruction pixel size of 36 μm. In the mandible body group, the differences of all parameter values between different pixel sizes were significant. Conclusion: Micro-CT can reflect the anatomical changes of bone trabecule structure.