Cone-beam computed tomography (CBCT) has strong potential to be utilized in various aspects of veterinary dentistry. Using ex vivo rat maxillary bone and teeth, the purpose of this study was to compare gray value, surface area, and volumetric measurements of teeth with and without experimental periodontitis by CBCT. Periodontitis was induced in 36 molar teeth, while 36 teeth with a healthy periodontium served as control. Images of each specimen along with teeth were obtained using CBCT. The following measurements for each tooth with periodontitis (n = 36) were recorded: gray value measurement, width, height, depth, surface area, and volume of the alveolar bone loss. For the control group (n = 36), gray value measurement, surface area, and volume of the alveolar bone were recorded. All measurements were repeated after 3 weeks. As the gold standard, the rat maxillas were decalcified and paraffin-embedded for further immunocytochemical study. One-way analysis of variance (ANOVA) was used. Significance level was set at P < .05. Correlation values for gray value, width, height, depth, surface area, and volume measurements were 0.983, 0.966, 0.962, 0.880, 0.998, and 0.999, respectively, for the first and second measurements. One way ANOVA showed statistically significant differences between teeth with and without alveolar bone destruction conducted for gray value, surface area, and volume measurements ( P = .000). Mean gray value, surface area, and volume measurements decreased 56.46%, 81.89%, and 78.56%, respectively, for teeth with alveolar bone destruction in comparison to healthy teeth. Cone-beam computed tomography provided useful qualitative and quantitative information regarding induced periodontitis in the rat maxilla.