锥形束CT对上颌第一前磨牙根管增龄性变化的观察

Aging changes of the root canal morphology in maxillary first premolars observed by cone-beam computerized tomography

目的 应用锥形束CT研究上颌第一前磨牙根管形态的增龄性变化,为不同年龄患者的临床治疗提供参考.方法 选择2011年3月至2015年6月就诊于暨南大学附属第一医院口腔医疗中心290例患者的405颗上颌第一前磨牙锥形束CT影像资料,按年龄分为6组：11 ～ 20岁、21～ 30岁、31～ 40岁、41～ 50岁、51 ～ 60岁及＞60岁组,分析各组根管类型、单根牙双根管发生率、双根管两根管口之间距离、根管横断面形态4项指标与年龄的关系,对6组上颌第一前磨牙的4项指标进行卡方检验,同时采用有序分组资料的线性趋势检验分析其增龄性变化.结果 各年龄组根管类型分布差异有统计学意义（P＜0.05）.上颌第一前磨牙根管类型以Ⅳ型最多见[51.8％ （210/405）],其次为Ⅱ型[16.0％（65/405）]、Ⅰ型[13.6％（55/405）]及Ⅲ型[6.7％ （27/405）],随着年龄的增长,Ⅰ型和Ⅲ型逐渐减少,Ⅱ型逐渐增多,而Ⅳ型无明显的变化规律;单根牙双根管发生率随着年龄增高而增加,20岁以后双根管发生率出现快速增长,由11～ 20岁的51.7％（31/60）上升至21～ 30岁的83.0％（44/53）,而40岁以后增幅明显减缓;双根管两根管口之间距离随着年龄增长而缩短,40岁以后缩短的幅度明显减缓;根管横断面形态以扁形[48.5％（1 020/2 105）]和椭圆形[28.2％（594/2 105）]为主,随着年龄增长圆形逐渐增加,扁形和椭圆形呈下降趋势.结论 锥形束CT能清晰显示根管的形态及走向,上颌第一前磨牙根管形态与年龄存在一定关系,随着年龄增长根管形态更加复杂.

Objective To observe the morphological changes of root canals with aging in maxillary first premolars by using cone-beam computerized tomography（CBCT） in order to facilitate endodontic management of root canals in various aged patients.Methods The digital CBCT data of the maxillary first premolars in 405 cases from the patients in Oral Medical Center of The First Affiliated Hospital,Jinan University from March 2011 to June 2015 were collected.The CBCT images were divided into 6 groups according to the patients＇ ages：groups 11-20,21-30,31-40,41-50,51-60 and 〉60 years-olds,respectively.Changes of morphologies of root canals with aging including such parameters as types of the root canal,incidence of double root canals in single rooted teeth,distance between both root canal orifices of double rooted canals,and morphological change of the cross section of roots.Chi-square test and liner trend testwere adopted in statistical analysis in the present study.Results The distribution of various types of the root canals were significantly different amongst various aged groups（P〈0.05）.Type Ⅳ is the most common type （210/405,51.8%）,and the following groups were type Ⅱ （65/405,16.0%）,type Ⅰ （55/405,13.6%） and type Ⅲ （27/405,6.7%）.Along with aging,the percentages of type Ⅰ and type Ⅲ decreased while type Ⅱ increased.However,there were no remarkable changes of type Ⅳ observed.The incidence of double rooted canals in single rooted teeth gradually increased with aging especially in 20-years-old and above groups,e.g.51.7%（31/60） in group 11-20 years-olds and 83.0%（44/53） in group 21-30 years-olds.However,there was no significant increase observed after the age of 40.The distance between both root canal orifices of double rooted canals became shorter with aging except in groups of 40-years-olds and above.The morphologies of the cross sections in most aged groups were flat shaped（1 020/2 105,48.5%） and oval shape （594/2 105,28.2%）.Along with aging,the percentage of circular shape gradually increased while flat and oval shapes decreased.Conclusions The morphology of root canal could be clearly showed by the CBCT images.The change of morphologies of the root canals in maxillary first premolars was significantly related to aging.Along with aging,the morphology of the root canal became more and more complicated.