Objective: To establish a protocol for assessing orthodontically induced tooth root resorption (OITRR) in human premolars using micro-computed tomography.
Materials and methods: Ten extracted maxillary first premolars were obtained from eight healthy adolescent patients; five of these premolars were extracted before any orthodontic movement was applied to them, and the other five premolars were involved in nonextraction orthodontic treatment for 1 year before treatment plan modification lead to extraction treatment. Using reconstructed scanned images, we measured several key resorption lacunae parameters, including the number, volume, and depth on each surface, as well as its extension coronoapically.
Results: Orthodontic treatment resulted in a significantly greater tooth root resorption lacunae volume, number, maximum depth, and coronoapical extension as well as in areas of dentin demineralization subjacent to the resorption lacunae than in normal premolars.
Conclusions: We have established a protocol to evaluate OITRR quantitatively and have provided a method to predict further resorption based on dentine demineralization.