Objectives: The purpose of the present study was to retrospectively analyze 170 case series of patients with 200 impacted first and second permanent molars. Study Design: Records of 104.408 patients were retrospectively screened in this multicenter study. The chosen study population consists of 170 patients who presented with impacted or retained first and second permanent molar. All patients with impacted first or second permanent molar had undergone clinical and radiographic examinations. The following factors were analyzed: age and gender, frequency, distribution, location, position, the number of impacted tooth, primary and secondary retention, degree of infraocclusion, associated pathologic conditions and treatment method. Results: There were a total of 170 patients (male: 91, female: 79, mean ages 22.69±8.99 years ranging from 13 to 66 years of age) with 200 retained or impacted permanent molars in 104.408 patients. In this study, 200 impacted teeth which were analyzed were 125 molars (62.5%) vertical position, 17 (8.5%) horizontal, 38 (19%) mesioangular, 12 (6%) distoangular, and 7 (3.5%) buccolingual inclination. There were 52 primarily retained (26%) and 32 secondarily retained (16%) molars. 137 (68.5%) molars were asymptomatic. Cystic formation was present in 13 (6.5%) cases. Conclusions: Although the impactions of first and second permanent molars do not occur frequently, it is important to make an early diagnosis in order to start treatment at the optimal time. © Medicina Oral S.L.