Prevalence and associated factors of radiolucency in the distal surface of mandibular second molar related to impacted third molars in Nepalese population: A cross-sectional study using panoramic radiographs
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Abstract
Objectives: The objective of this study was to determine the prevalence of distal surface radiolucency in mandibular second molars adjacent to impacted third molars in panoramic radiographs in Nepalese population and evaluate the relationship between patient characteristics, impacted tooth status, and the presence of distal radiolucency in mandibular second molar.
Materials and Methods: This is a cross-sectional study where panoramic radiographs were collected from a tertiary hospital’s records. Two surgeons evaluated the radiographs. The angulation of impacted third molars was classified by Winter’s classification modified by Quek et al., and the occlusal position relative to second molar and distal space mesial to anterior border of ramus by Pell and Gregory classification. Age, gender, and side were also noted. Chi square test and multivariable logistic regression were done.
Results: A total of 269 patients with 335 impacted teeth were included in the study. The mean age of patients was 31.91 ± 12.45 years, with 128 (47.58%) males and 282 (52.42%) females. The prevalence of distal surface radiolucency in mandibular second molar was 113 (33.7%). Among them, significant association was found in Age, Right side of jaw with 74 (65.48%) third molars, Mesioangular with 57 (50.44%) third molars, Class I with 64(56.6%) third molars and Position A with 64 (56.6%) third molars. Multivariable logistic regression showed significant association between age (AOR = 1.03, 95% CI: 1.01–1.05, p < 0.01), Right side of jaw (AOR = 1.97, 95% CI: 1.14–3.41, p = 0.015); Mesioangular impaction (AOR = 2.57, 95% CI: 1.47–4.51, p = 0.001), Class I (AOR = 4.93, 95% CI: 2.79–8.73, p < 0.001), and position A (AOR = 2.15, 95% CI: 1.22–3.79, p = 0.008) compared to other respective groups combined.
Conclusions: Mesioangular, Class I, Position A, and right-sided impacted third molars showed more radiolucency in second molars as compared to others. This study also aimed to explore how ethnicity and regional variance influence the presentation of impacted third molars and associated second molar pathology, given that in Nepal, financial constraints often lead patients from resource-limited settings to opt for extraction of the carious second molar itself rather than costly restorative treatment. By characterizing these patterns, the study aims to support the case for prophylactic third molar removal as a more cost-effective and beneficial alternative for this population.
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