改良唇挡单侧扩弓后牙槽骨高度与厚度变化的CBCT研究

目的 研究改良唇挡单侧扩弓后裂侧牙槽骨高度与厚度的变化.方法 对年龄在12～16岁应用改良唇挡完成单侧扩弓的18名单侧完全性唇腭裂患者扩弓前后的CBCT图像进行重建,测量扩弓后裂侧牙槽骨高度与厚度,对测量结果进行统计学分析.结果 裂侧尖牙、第一、第二前磨牙颊、腭侧牙槽骨的高度均降低,其中尖牙变化量最大(P<0.01),尖牙颊侧骨开裂的患者增多.第一、第二前磨牙颊侧牙槽骨在釉牙骨质界下4mm、6mm处厚度增加,尖牙颊侧在6mm处骨厚度增加(P<0.01),在4mm处骨厚度减少(P<0.05),尖牙、第一、第二前磨牙腭侧牙槽骨厚度减少.结论 唇挡扩弓后,裂侧牙齿颊侧牙槽骨的高度降低,厚度增加.对于裂侧尖牙正畸治疗前后的牙周状况应该引起重视.

Evaluation of alveolar bone changes in patients with unilateral complete cleft lip and palate after unilateral expansion with the modified lip bumper by CBCT

Objective To evaluate the effect of unilateral maxillary expansion with modified lip bumper on alveolar bone thickness and alveolar bone height using cone beam computed tomography(CBCT).Methods Eighteen patients (12 to 16 years) with unilateral complete cleft lip and palate(UCLP)treated with the modified lip bumper were included and the alveolar bone thickness and alveolar bone height evaluated by CBCT before and after treatment.Results The modified lip bumper significantly reduced alveolar bone height of the canines (P<0.01)and the first and second premolars on the affected side and increased the incidence of dehiscence of the alveolar bone surrounding the canine teeth.The buccal alveolar bone thickness of the first and second premolars increased in the 4mm and 6mm areas under cement-enamel junction (P<0.05).The buccal alveolar bone thickness of the canines increased in 6 mm area under cement-enamel junction (P<0.01),but decreased in 4mm area(P<0.05).The palatal alveolar bone thickness of the canines and the first and second premolars decreased.Conclusion The modified lip bumper may decrease the alveolar bone height and increase the buccal alveolar bone thickness on the affected side.