Chun-Ming Chen1, Shih-Wei Liang2, Szu-Ting Chou3, Dae-Seok Hwang4, Uk-Kyu Kim4, Yu-Chuan Tseng5. 1. School of Dentistry and Graduate Program of Dental Science, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. 2. School of Dentistry and Graduate Program of Dental Science, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan. 3. School of Dentistry and Graduate Program of Dental Science, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. 4. Department of Oral and Maxillofacial Surgery, Pusan National University Dental Hospital, Pusan, South Korea. 5. School of Dentistry and Graduate Program of Dental Science, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Electronic address: yct79d@seed.net.tw.
Abstract
BACKGROUND/ PURPOSE: The neurosensory disturbance is a common complication following sagittal split ramus osteotomy (SSRO) whereas the shortest buccal bone marrow (SBM) is an important risk factor. The present study aimed to investigate the relationship between the occurrence rates of SBM among three skeletal patterns. METHODS: The cone-beam computed tomography (CBCT) images of 90 participants were divided into skeletal Class I, II, and III. There were six horizontal planes separated apart by a 2 mm interval; it started with plane 0 (original intact mandibular canal) to plane 5 which was 10 mm below. The data of SBM were divided into two groups (SBM ≥ 1 mm and SBM < 1 mm). With an SBM value < 1 mm, we defined a high occurrence rate of postoperative neurosensory abnormality or unfavorable split. RESULTS: The Class III patients had the smallest SBM value (1.31-1.75 mm) whereas the Class II patients had the largest SBM value (1.57-2.09 mm). For the Class III patients, the highest and lowest occurrence rates of SBM were 56.5% and 43.5% respectively. For the Class II patients, the highest and lowest occurrence rates of SBM were 37.1% and 17.7% respectively. The patients with Class III malocclusion had higher occurrence rates of SBM than the patients with Class II malocclusion. CONCLUSION: Class III had a significantly higher occurrence of probability (SBM < 1 mm) than Class II. Therefore, patients with Class III were more likely to experience postoperative neurosensory abnormalities and unfavorable split than patients with Class II.
BACKGROUND/ PURPOSE: The neurosensory disturbance is a common complication following sagittal split ramus osteotomy (SSRO) whereas the shortest buccal bone marrow (SBM) is an important risk factor. The present study aimed to investigate the relationship between the occurrence rates of SBM among three skeletal patterns. METHODS: The cone-beam computed tomography (CBCT) images of 90 participants were divided into skeletal Class I, II, and III. There were six horizontal planes separated apart by a 2 mm interval; it started with plane 0 (original intact mandibular canal) to plane 5 which was 10 mm below. The data of SBM were divided into two groups (SBM ≥ 1 mm and SBM < 1 mm). With an SBM value < 1 mm, we defined a high occurrence rate of postoperative neurosensory abnormality or unfavorable split. RESULTS: The Class III patients had the smallest SBM value (1.31-1.75 mm) whereas the Class II patients had the largest SBM value (1.57-2.09 mm). For the Class III patients, the highest and lowest occurrence rates of SBM were 56.5% and 43.5% respectively. For the Class II patients, the highest and lowest occurrence rates of SBM were 37.1% and 17.7% respectively. The patients with Class III malocclusion had higher occurrence rates of SBM than the patients with Class II malocclusion. CONCLUSION: Class III had a significantly higher occurrence of probability (SBM < 1 mm) than Class II. Therefore, patients with Class III were more likely to experience postoperative neurosensory abnormalities and unfavorable split than patients with Class II.