A collaborative survey on occlusion after orthodontic treatment in patients with unilateral cleft lip and palate in Japan

Abstract Purpose A nationwide collaborative survey was performed in Japan to evaluate the recent treatment outcomes on occlusion after orthodontic/orthognathic treatment for patients with unilateral cleft lip and palate (UCLP). Methods A retrospective collaborative survey was performed. Twenty-five facilities, including 14 university hospitals, examined their orthodontic records and cast models of patients with UCLP. Using common format, information of 492 non-syndromic UCLP cases were reported. Patients with syndromic UCLP or congenital missing maxillary central incisors were excluded. Basically, each facility reported their most recent 30 cases. Results Of 492 cases, 330 cases (67.1%) were reported from 11 facilities, suggesting that orthodontic treatment for patients with CL/P was not fully centralized in Japan. Secondary alveolar bone grafting and orthognathic surgery were performed in 92.7% and 22.5% of cases, respectively. A significantly higher rate of orthognathic surgery was seen in cases reported from university hospitals (27.5%) than other facilities (14.8%). Average age at the end of active orthodontic/orthognathic treatment was 18.5 years. The lateral incisors on cleft sides were congenitally missing in 50.2% and displayed microdontia in 42.9% of cases. After orthodontic treatment, the central incisors and the canines were aligned without interdental spaces in 55.3% of cases. The positive anterior overjet was seen in 88.2%, and the centerline discrepancies between maxillary and mandibular incisors within 1/4 of mandibular incisor width was in 74.8% of cases. Conclusions The final occlusion after orthodontic treatment was satisfactory in most cases. Findings of this study are referable for improving standard Japanese orthodontic care for patients with CL/P.