Journal of Mazandaran University of Medical Sciences (Mar 2024)
Evaluation of the Vegetative State of the Impacted Mandibular Third Molar and the External Root Resorption of the Adjacent Second Molar
Abstract
Background and purpose: The impaction of a third molar tooth poses a significant challenge for dental practitioners. It is a multifaceted issue with diverse pathological factors contributing to dental arch collapse and root resorption in adjacent teeth. The purpose of this study was to scrutinize the vegetative state of the mandibular wisdom tooth and the adjacent second molar`s external root resorption. Materials and methods: In this cross-sectional and analytical epidemiological study, CBCT images of about 500 mandibular third molars were examined. Third molar teeth with mesioangular or horizontal impaction were included in the study. All images were prepared by CBCT CS9300 device (Carestream Dental LLC, Atlanta, Georgia) with the same exposure parameters. The images were evaluated by a final year dental student under the supervision of an oral, maxillofacial radiologist in a semi-dark room and LG monitor (LCD, 20 inch, 1600×900 pixel) in sagittal, axial and coronal planes. The images were classified based on the position of root external analysis as 1.3 apical, middle, and cervical root. The severity of external root erosion in the second molar tooth is also divided into three categories: Slight (A very small amount of dentin is involved), Moderate (Half of the dentin is involved), and Severe (Pulp cavity is involved). Also, its relationship with age and gender was determined and finally analyzed using SPSS software (version 22). Results: In the present study, a total of 500 wisdom teeth were observed in CBCT images, of which 101 impacted wisdom teeth had a mesioangular or horizontal position. we found that the prevalence of impacted wisdom teeth with mesioangular (68 cases) and horizontal (33 cases) positions was about 20.2% and the prevalence of external analysis in the mandibular second molar root associated with impacted wisdom teeth was about 10.9%. The prevalence of external analysis was higher in women than in men (P=0.04). In determining the position of external resorption and its severity in the root of the second molar, it was also found that the highest position of external resorption of the root was related to the middle part of the tooth (63.7%) and the lowest was related to the apical part (9.2%). In examining the severity of external root resorption, we found that in 89.1% of the samples, root resorption of the second molar tooth was not observed. In the examination of the age group, it was found that the analysis was more common in the age group of 18-30 years (P=0.04). The only sample with moderate analysis was in the age group of 45-55 and male. The age group of 18-30 years and women have significantly more brief analysis than their corresponding groups. The relationship between the type of lower wisdom tooth impaction and the frequency of external analysis of the adjacent second molar root was statistically significant (P=0.03). the results of the relationship between the type of mandibular wisdom tooth impaction and the severity of external resorption of the adjacent second molar root, it was observed that there was a statistically significant relationship between the type of lower wisdom tooth impaction and the severity of external resorption of the adjacent second molar root (P=0.01). Moreover, the severity of the analysis was more intense in the horizontal position than in the mesioangular position. Conclusion: Based on the results of this research, it can be concluded that the age group of the patient, gender, and position of the impacted third molar are the most influential factors regarding the external root resorption of the adjacent molar. There is a statistically significant relationship between the type of lower wisdom tooth impaction and the frequency and severity of external resorption of the adjacent second molar root.
