External root resorption in common odontogenic cysts and ameloblastomas of the jaw: A retrospective radiographic study in an Asian population

Aim To evaluate the frequency of external root resorption on adjacent teeth of common cysts and ameloblastomas of the jaw in an Asian population and to investigate the association of size or location of the lesions on such root resorption potential. Material and methods A retrospective radiographic study using cone beam computed tomography (CBCT) scans to examine the frequency of external root resorption (ERR) of teeth in proximity of 160 lesions comprising periapical radicular cysts, dentigerous cysts, odontogenic keratocysts and ameloblastomas was carried out. Fisher's exact test, Pearson's chi square test and logistic regression analysis were used to investigate differences in the frequency of ERR of teeth adjacent to these lesions and to assess the association of the size or location of the lesions on such root resorption potential. Results and conclusions There were 40% of lesions located in the maxilla and 60% in the mandible. Adjacent teeth ERR was noted in 61 (38.1%) lesions. Compared with odontogenic keratocysts, ameloblastomas were eight times more likely (p = 0.005) and dentigerous cysts were three times more likely (p = 0.028) to be associated with ERR after adjusting for the size and location of the lesion. Location and size of a lesion did not influence the prevalence of adjacent teeth ERR. The four types of lesions studied exhibit different frequencies of ERR in adjacent teeth. Based on this study, the presence of ERR in adjacent teeth is a useful supportive measure in the diagnosis of these lesions.