锥形束CT对微螺钉植入后牙安全区域的分析

目的通过锥形束CT（CBCT）测量上下颌后牙区不同高度牙槽骨近远中向及颊舌（腭）向的骨量,分析微螺钉种植体植入的安全区域。方法选取30例CBCT扫描的成人影像资料为研究对象,对颌骨进行扫描重建,从第前磨牙远中开始向后,在每个牙根间区域（包括上颌结节）距离牙槽嵴顶2、4、6、8、10 mm处,分别测量颊舌（腭）向宽度和近远中宽度。采用SPSS 16.0软件进行单因素方差分析和LSD法比较。结果1）上颌后牙区近远中骨量在同一高度不同位置间均存在统计学差异（P<0.05）,最大近远中骨量位于第二前磨牙和第一磨牙腭侧根间;颊腭向骨量在不同位置、高度间均有统计学差异（P<0.05）,最大颊腭向骨量位于第一磨牙和第二磨牙之间。2）下颌后牙区近远中骨量在不同位置、高度间均有统计学差异（P<0.05）,颊舌向骨量在同一位置不同高度间均存在统计学差异（P<0.05）,最大近远中骨量和最大颊舌向骨量均位于第一磨牙和第二磨牙之间。结论经CBCT获取了上下颌骨后牙段植入微螺钉种植体的安全区域,为后续临床应用提供了有价值的参考。

Research about the safe zone of microscrew implant insertion for back teeth by cone beam computed tomography

Objective To measure the mesiodistal and buccolingual alveolar bone mass of back teeth in posterior alveolar crest at different height by cone beam computed tomography(CBCT),and analyze the safe area of microscrew implanted at back teeth in posterior alveolar crest.Methods 30 cases of adult scan image data were selected for the study of jaw bones scan reconstruction.From the distal of first premolar backward,buccolingual(plate) width and the mesiodistal size between each interfurcal region(including tuber maxillae) were measured from alveolar crest at top of 2,4,6,8,10 mm.ANOVA and LSD methods were made by SPSS 16.0 software for comparison.Results 1)The mesiodistal bone mass of back teeth in maxilla at the same height with different position had statistically significant difference(P<0.05).The biggest mesiodistal bone mass was located at the palatal roots between the second premolar and the first molar.The statistically significant difference of buccolingual bone mass also existed at different position and height(P<0.05).The biggest buccolingual bone mass was located at the middle of the first molar and the second molar.2)The mesiodistal bone mass of back teeth in maxilla at different height and position had statistically significant difference(P<0.05).The statistically significant difference of buccolingual bone mass also existed in the same position with different height(P<0.05).The biggest mesiodistal and buccolingual bone mass was located at the middle of the first molar and the second molar.Conclusion The safe area of microscrew implanted at back teeth in posterior alveolar crest is tested by CBCT,which provides valuable reference for the follow-up clinical application.