Objectives: Pediatric mandibular distraction osteogenesis (MDO) is an increasingly common surgical procedure used to lengthen the mandible. Little is known about the long-term effects of MDO on dental development. This retrospective study sought to identify dental abnormalities at mixed dentition and early permanent dentition stages in patients who had undergone MDO. Methods: All pediatric patients who underwent MDO with imaging and clinical exams at mixed dentition and early permanent dentition stages were evaluated identify pathology. Data included demographic information, medical and surgical history, complications, and dental exam information. Descriptive statistics were reported. Results: Twenty-two hemimandibles at mixed dentition stage and 24 at early permanent stage were included. Mean age at initial MDO was 7.95 years with a mean follow-up time of 15.1 years. Nine patients required more than 1 distraction. At the mixed dentition stage, all patients showed abnormalities. The most common abnormalities were absent, dysplastic, or ectopic molars. At early permanent dentition stage, 87.5% of patients had dental abnormalities. The most common abnormality was missing molars (third, second, and first), but dysplastic, impacted, and ectopic teeth were also noted. At both mixed and early permanent dentition stages, some patients were noted to have abnormal V-shaped sigmoid notching of the mandibular ramus of undetermined clinical significance. Buccal mucosal scarring that interfered with orthodontic treatment was observed in a subset of patients. Conclusions: This study provides long-term dental analyses of patients undergoing MDO for mandibular hypoplasia. Dental abnormalities were seen at both mixed and early permanent dentition stages. Molars were the most commonly affected with absence the most commonly seen abnormality. Dysplastic, ectopic, and impacted teeth were also seen in posterior and anterior dentition, and abnormalities in buccal soft tissue and the mandibular ramus were also seen. MDO remains a crucial tool for functional and aesthetic improvement in children with hypoplastic mandibles. Dental abnormalities as a consequence of MDO should be considered as part of surgical planning process.