Evaluation of the relationship between tooth impaction and root dilaceration using CBCT

Abstract

Introduction: The abnormal angle or curvature in the root or crown of the tooth is defined as dilaceration. Dilaceration is often observed in the roots of impacted teeth. The use of CBCT leads to the accurate identification of the location, direction and degree of dilacerations. The purpose of this study is to investigate the relationship between tooth impaction and root dilaceration using CBCT image.

Materials and methods: In this cross-sectional study, 160 CBCT images in different sections of coronal, axial and sagittal were examined and dilaceration angle, gender of the patient, jaw type (upper and lower jaw), tooth side (right/left) and buccal/palatal orientation of the impacted tooth were recorded. An angle or curvature of more than 20 degrees in the root compared to the longitudinal axis of the tooth was recorded as dilaceration. The collected data were entered into SPSS software version 21. For qualitative variables, frequency and percentage and for quantitative variables, mean and standard deviation were calculated. To investigate the relationship between impaction and dilacerations, the chi-square test was performed, and in cases with lower frequency than expected, the equivalent of chi-square, i.e. Fisher's exact test, was performed. The significance level in all tests was considered less than 5%.

Results: The teeth with the highest number of impaction were third molar, canine and second premolar, respectively. Also, the prevalence of dilaceration was reported to be 25% in impacted teeth and 10% in the opposite teeth that were not impacted. In impacted teeth, the highest prevalence of dilaceration was in the age group under 20 years and was seen in women, maxilla, Canine tooth and distal side. It can be said that there is a statistically significant relationship between tooth impaction and dilaceration, so that the possibility of dilaceration in impacted teeth is 2.65 times that of non-impacted teeth.

Conclusion: There is a relationship between tooth impaction and dilaceration, and dilaceration greatly increases the chance of tooth impaction; but tooth impaction does not increase the chance of dilaceration.