【摘要】 目的利用锥形束计算机断层扫描(CBCT)分析研究上颌第一磨牙压低量与上颌窦位置的关系。方法收集2016年9月至2018年1月郑州大学第一附属医院口腔正畸科收治的上颌第一磨牙压低的60例患者治疗前的CBCT影像资料,根据上颌第一磨牙上颌窦底壁的关系,分为3组,A组(上颌第一磨牙根尖均远离上颌窦,即d>0 mm)20例,B组(上颌第一磨牙牙根与上颌窦关系密切,即d=0 mm)20例,C组(上颌第一磨牙至少有1根突入上颌窦内,即d<0 mm)20例。收集治疗后相对应的CBCT影像,通过invivo 5.2软件测量上颌第一磨牙压低量,分析根尖吸收情况,上颌窦改建情况,并使用SPSS 20.0软件进行统计学分析。结果 A组与B组差值MB-A、差值DB-A、差值P-A比较,差异无统计学意义(均P>0.05)。C组与A组、B组比较,差异有统计学意义(均P<0.05)。A、B、C组中各牙根吸收等级占比比较,差异有统计学意义(均P<0.05)。结论上颌第一磨牙的腭根与上颌窦关系比近远中颊根密切,牙根少量突入到上颌窦底(≤根长1/3)时,可在适当的正畸力作用下安全有效的压低并达到预期水平,且较少出现牙根吸收。更多还原

【Abstract】 Objective To study the relationship between maxillary first molar hypotension and maxillary sinus position by cone beam computed tomography(CBCT).Methods From September 2016 to January 2018, 60 patients with maxillary first molar depression treated by orthodontic department of the First Affiliated Hospital of Zhengzhou University were collected and divided into three groups according to the relationship between the maxillary first molar and the maxillary sinus base wall, there were 20 cases in group A(the root apex of the first maxillary molar was far from the maxillary sinus, d>0 mm), 20 cases in group B(the root of the first maxillary molar was closely related to the maxillary sinus, d=0 mm), and 20 cases in group C(at least one maxillary first molar protruding into the maxillary sinus, there was at least one protrusion of the maxillary first molar in the maxillary sinus, d<0 mm). CBCT images corresponding to the treatment were collected, and the depression of maxillary first molar was measured by invivo 5.2 software to analyze root tip absorption and maxillary sinus reconstruction. SPSS 20.0 software was used for statistical analysis.Results There were no significant differences between group A and group B in MB-A, DB-A and P-A(all P>0.05). Group C was compared with group A and group B respectively, and the differences were statistically significant(all P<0.05). The proportions of root resorption levels in groups A, B and C were statistically significant(all P<0.05).Conclusion The palatal root of the maxillary first molar is more closely related to the maxillary sinus than the proximal buccal root. When a small amount of the maxillary root is protruded to the bottom of the maxillary sinus(≤1/3 of the root length), it can be safely and effectively depressed under the appropriate orthodontic force and reach the desired level, and root resorption was rarely seen.更多还原