Prevalence and Pattern of Third Molar Impaction Assessed from Orthopantomograms Among Patients at Rajavithi Hospital

Abstract

Background: Impacted teeth, if left untreated or under inappropriate treatment, have the potential to inducevarious complications. Objective: To determine the prevalence and pattern of impacted third molar by radiographicevaluation. Methods: This retrospective study was performed on patients who had an oral examination at theDental Department, Rajavithi Hospital between May 2017 and September 2017. Data were collected regarding thebaseline characteristics and orthopantomograms (OPG). Data were then analyzed using SPSS software version 22.0.The ethics committee of Rajavithi Hospital has reviewed and approved this study. Results: Among the 852 patientsincluded in the study, 71.8% were female with a mean age of 29.30 ± 11.20 years old. The pattern of the impactedthird molar, 3,107 teeth, was reviewed by radiographic evaluation. 65.9 percent were classified as impacted, of which33.5% were in the mandibular left third molar. The maxillary right and left third molars had impaction in level B at52.7% and 55.1%, vertical angular at 62.0% and 64.7%, respectively. The mandibular left and right third molars hadimpaction in level A at 57.9% and 63.9%, mesioangular impaction was 32.8% and 37.3%, and class II was at 85.5%and 87.6%, respectively. Conclusions: The prevalence of impacted third molar in patients has revealed a high rate,which is found in females more than males. The most vertically impacted site is level B in a maxillary third molar,while the mandibular third molar impacted site is mainly mesioangular, level A, and class II.