@article{14296, author = {Gaute Johnsen and Joakim Sundnes and Jonas Wengenroth and H{\r a}vard Haugen}, title = {Methodology for morphometric analysis of modern human contralateral premolars}, abstract = {Objective: This study aimed at developing a standard methodology for morphometric analysis and comparison of contralateral human premolar pulp space using microcomputed tomography (micro-CT) and semi- automated software. The primary objective was to establish a method to compare the complex and minute morphological internal volumes of con- tralateral premolar pulp spaces and determine their degree of similarity. The secondary aim was to introduce new methodology for selecting contra- lateral premolars for the study of biomaterials and techniques. Methods: Forty-one intact human premolar pairs (n = 82) extracted from 28 patients were scanned with micro-CT. Quantitative comparative evalua- tion was performed through geometric morphometric deviation analysis of the pulp spaces after mirroring, automatic alignment, and coregistration with semiautomated software. Geometric parameters compared included volume, surface, and surface over volume. Shape deviation analysis of transformed mean distances and root mean square errors was conducted. Results: The geometric parameters of the contralateral premolar pulp spaces had significantly higher similarity coefficients than random pairs (P \< 0.001). The shape deviation analysis and transformed mean distances had significantly lower values for contralaterals compared with random pairs (P \< 0.001). The contralateral geometries had a statistically signifi- cant narrower distribution in deviation when compared with random pairs (P \< 0.001).Conclusions: We present a methodology that sets a new standard for internal validation of the teeth to be used in ex vivo testing of endodon- tic materials and techniques. It also shows that the resolution of the CT scan is crucial and that studies using cone beam CT cannot be used for such studies.}, year = {2016}, journal = {Journal of Computer Assisted Tomography}, volume = {40}, pages = {617-625}, publisher = {Wolters Kluwer Health}, }