摘要
目的研究唇挡早期矫治上颌拥挤病例引起的牙弓三维改变。方法选取正畸患者12例,平均年龄9.8岁。为缓解上颌的拥挤,戴用唇挡8个月。戴用唇挡前后取记存模型,进行三维数字化,以第三腭皱为参考将治疗前后的模型重叠,分析牙齿三维位置改变及倾斜度的变化。配对t检验比较治疗前后牙弓宽度和上牙弓弧形长度的差异。结果戴用唇挡后,牙齿三维方向的改变以后部牙弓的变化最为显著,矢状向上颌第一前磨牙、第一磨牙分别远中移动2.08、2.03mm,上牙弓弧形长度增加5.12mm;垂直向上颌第一前磨牙升高1.17mm,第一磨牙升高0.72mm;横向上颌第一前磨牙间宽度增加2.62mm,第一磨牙间宽度增加3.08mm;以上各测量均有统计学意义(P<0.05)。同时上颌切牙存在少量前移、扩宽和唇倾。上颌切牙唇倾度增加3.90°,第一磨牙远中倾斜度增加8.23°,有显著性差异(P<0.05)。结论上颌唇挡可以缓解轻中度的牙弓拥挤。唇挡引起的牙弓长度增加主要是由于磨牙的远中移动、后倾以及牙弓的扩宽。
Objective To evaluate the dental changes following the use of a maxillary lip bumper. Methods Twelve adolescents were selected. Study Casts were taken before and after treatment of lip bumper. The three-dimensional displacements and mesiedistal/buccolingual inclination of teeth were evaluated by Rapidform 6.0 using the palatal rugae as a stable reference. The difference in the arch width and the available arch length before and after treatment was statistically analyzed. Results After the use of lip bumper, the changes of posterior teeth in 3 dimension were evident. Sagittally, the first premolar and molar moved distally by 2. 08mm and 2. 03mm（P 〈 0. 05 ）. Vertically,the first premolar and molar were extruded by 1.17mm and 0. 72mm（P 〈0. 05）. Transversally,the first premolar and molar were expanded by 1.32 mm and 1.65mm（P 〈 0.05）. Incisors inclined to lip side by 3.9 degree, and molars tipped distally by 8.23 degree. The interpremolars width increased by 2.62ram,and the intermolar width increased by 3.08mm. The available dental arch length was increased by 5.12mm. Conclusion The early treatment by upper lip bumper can relieve the moderate crowding by distal and bueeal displacement and distal tipping of the first molars.
出处
《北京口腔医学》
CAS
2013年第4期206-208,共3页
Beijing Journal of Stomatology
关键词
唇挡
拥挤
早期矫治
数字化模型
Lip bumper
Crowding
Early treatment
Digital models
