【摘要】 目的:口腔锥形束CT(cone beam CT,CBCT)评价纳米羟基磷灰石(hydroxyapatite,HA)诱导年轻恒牙根尖形成的效果。方法:选用2只56月龄犬的16颗恒切牙,术前拍摄CBCT片测量根尖面积,经去髓后,随机分为4组,A组为实验组,用HA糊剂充填根管;B、C组为阳性对照组,分别用氢氧化钙(calcium hydroxyde,CH)、Vitapex充填;D组为阴性对照组,用AH plus糊剂充填。术后4周通过CBCT片观察根尖形态并与数字化X线根尖片对比。利用CBCT系统软件测量根尖面积,每组数据与术前相比行配对t检验,各组根尖面积减少值行单因素方差分析(ɑ=0.05)。结果(1)CBCT显示:A、B、C组根尖矢状面呈内聚状,未完全闭合,D组根尖呈平行开放状。A、B、C、D组根尖横断面均呈颊舌径较大的椭圆形,未闭合。根尖片显示:A、B、C组根尖呈内聚闭合状,D组根尖呈平行开放状。(2)CBCT显示:A、B、C各组根尖面积测量数据术后与术前对比均有缩小(配对t检验P<0.05),但3组间根尖面积缩小量差别不显著(方差分析(P>0.05)。D组术后与术前相比根尖无明显缩小(配对t检验P>0.05)结论:(1)CBCT与根尖片相比,能更准确反映根尖形态,适于根尖诱导术后评价。(2)HA能诱导根尖闭合,影像学观察其短期效果与CH、Vitapex差别不显著。更多还原

【Abstract】 Objective:To evaluate the efficacy of nanodimensional hydroxyapatite(HA) on the root formation in immature teeth of dogs by cone beam CT(CBCT).Methods Sixteen roots of permanent incisors of two dogs about five to six months were used,whose area of tips were measured by CBCT before operation.After the pulpectomy,roots were randomly divided into four groups.A was experimental group,which was filled with HA,and B,C were positive control groups filled with calcium hydroxide(CH) and Vitapex respectively.And D was negative control group filled with AHplus.The form of root tips were observed by CBCT after four weeks which was compared with the digital periapical radiography,meanwhile,the changes of area of tips were measured by cone beam CBCT,and the data was used to do the Paired Samples Test and the one-way analysis of variance(ANOVA) with a stander of ɑ=0.05.Results(1)CBCT showed that all roots in every groups were not closed entirely whose shape were ellipse on the cross section.Digital periapical radiography showed that the tips of groups of A、B and C were cohesive and closing,however,D group was parallel and open wide.(2)The diminution of area of tips in the groups of A,B and C were significant(Paired Samples Test P<0.05) that there were no significant difference between them(ANOVA P>0.05),however,the diminution is not obvious in D group(Paired Samples Test P>0.05).Conclusion(1)We can get a more accurate appearance of tips by CBCT which is referred to apexification(2) the HA has good biological activity in apexification which is no significant difference compared with CH and Vitapex by a temporary observation of iconography.更多还原