Lower third molar impaction forecast based on angulation of their axis on panoramic x-rays

The aim of the study was to evaluate the diagnostic value (sensitivity and specificity) of lower third molar bud impaction in 121 patients aged 7 to 23 years who presented to an orthodontic clinic with complaints of different malocclusions. All patients underwent multiple panoramic radiographs during orthodontic treatment, specifically: before treatment initiation, after completion of phase 1 therapy, after fixed appliance therapy, and during the retention period. A retrospective analysis was conducted on a total of 1,085 lower third molar buds across 551 panoramic radiographs obtained from patients with maloclusions before, during, and after orthodontic treatment, as well as during the retention phase. The study revealed that starting from the age of 14, the inclination angle of lower third molar buds allow prediction of their impaction rate with a sensitivity of 64.8±6.5% and a specificity of 71.4±6.0%. As age increases, higher sensitivity and specificity enable impaction rate prediction even with smaller angles (less than 40°). The application of these diagnostic methods can enhance the effectiveness of preventive measures for pathological conditions associated with delayed tooth eruption.