【摘要】 目的:研究青少年上颌含牙囊肿囊内阻生尖牙(dentigerous cyst-associated maxillary canines,DCAMC)在行开窗减压术后的三维变化。方法:34名年龄为10～14岁的青少年DCAMC患者分为中央型DCAMC及侧方型DCAMC,并以健侧未完全萌出的正常尖牙作同体对照。使用锥形束CT(cone beam computed tomography,CBCT)建立用以测量的三维坐标系,观测开窗减压术前及术后3～6个月阻生尖牙各标志点间的三维位置、角度改变,并分析其影响因素。结果:1)对比术前,开窗术后DCAMC垂直向移动量显著,牙尖点向唇侧移动,伴随牙长轴近远中倾斜改变;2)DCAMC冠根点水平向及垂直向移动量、近远中倾斜度变化均大于健侧尖牙;3)中央型DCAMC相比于侧方型DCAMC,术后牙齿唇倾度明显改变;4)侧方型DCMAC水平向位移、近远中向倾斜度及唇倾度变化均大于中央型DCMAC;5)DCMAC垂直位移和倾斜变化与间隔时间呈显著正相关(r=0.354,0.374,均P<0.05),而健侧尖牙垂直位移与年龄及牙根形成水平呈显著负相关(r=–0.506,–0.721,均P<0.01)。结论:青少年含牙囊肿行开窗减压术后,囊内阻生牙无论牙根成熟与否,均可获得明显的位置及角度变化,有利于后续正畸治疗。更多还原

【Abstract】 Objective: To observe th ree-dimensional changes of dentigerous cyst-associated maxillary canines(DCAMC) in adolescents after marsupialization by using cone beam computed tomography(CBCT).Methods: A total of 34 DCAMC patients with dentigerous cyst aged 10–14 were divided into central type and lateral type, while canines on the non-cyst side served as a control. A th reedimensional reference frame was set up to analyze the position, angle changes and influential factors for DCAMC by using CBCT before operation and in 3–6 month after operation. Results: 1) Compared with pre-operation, there was significant vertical movement in DCAMC after marsupialization. Tip of tooth moved labially while tooth axis inclined mesiodistally; 2) Horizontal, vertical movement and mesiodistal inclination of DCAMC were significantly greater th an those in the health side; 3) Compared with the lateral type DCAMC, the central type DCAMC showed a significant changes in labial inclination; 4) Horizontal movement, mesiodistal and labial inclination of lateral type DCAMC were all evidently greater th an those of the central type DCAMC; 5) Vertical movement and inclination of DCAMC after marsupialization were significantly correlated to the time interval(r=0.354, 0.374, both P<0.05), while vertical movement of cuspid in health side was significantly negative correlated with the patients’ age and the level of root formation(r=–0.506, –0.721, both P<0.01). Conclusion: DCAMC in adolescents can obtain obvious changes in position and angles after marsupialization regardless of the level of root formation, which is beneficial for further orth odontic treatment.更多还原