A retrospective study on impaction of mandibular second molar

OBJECTIVES. The aim of the study was to determine the prevalence of impacted mandibular second molar (MM2) in orthodontics patients. The clinical signifisecond mandibular molar, crowding and (MM1) and the anterior margin of mandibular ramus in MM2 impaction were also evaluated. MATERIALS AND METHODS. 40 subjects of 2,945 orthodontics patients with MM2 impaction were included in a study group (SG) and compared with a control group (CG) of 200 subjects without MM2 impactions. Descriptive statistics and Student's T-test were used. RESULTS. The prevalence of impacted MM2 was 1.36%. The comparison between SG and CG showed a statistically significant difference (p = 0.00). CONCLUSIONS. MM2 impaction is a relatively rare occurrence which is characterized by crowding, a higher angle value of MM2 inclination and a reduced distance between MM1 and the anterior margin of mandibular ramus.