上颌第一磨牙位点在CBCT中的解剖学表现

Anatomical Presentation of Maxillary First Molar Site in Cone-beam CT

目的:通过CBCT分析上颌第一磨牙(M1)位点的相关骨解剖特点。方法:回顾分析548例上颌窦CBCT影像资料。对上颌窦外侧壁厚度(LWT)、上颌窦宽度(SW)、角度A、鼻腭凹角(PNR)、鼻腭凹角至牙槽嵴顶平面的垂直距离(DPA)等参数进行统计分析。窦底垂直向上5 mm、10 mm处对应的LWT、SW分别记作LWT-5、LWT-10、SW-5、SW-10。结果:LWT-5、LWT-10分别为(1.99±1.07)mm、(2.32±1.60)mm。SW-5、SW-10分别为(14.56±2.83)mm、(19.81±3.91)mm。角度A<30°、30°~60°、>60°者分别为0.18%、13.14%、86.68%。PNR<90°、≥90°者分别为9.85%、90.15%。DPA<15 mm且PNR<90°者占5.66%。男性LWT-5、SW-5、SW-10大于女性(P<0.05)。正常组LWT-5、SW-5、DPA大于缺牙组(P<0.05)。各年龄组间SW-5差异显著(P<0.05)。外侧璧骨性血管检出者LWT-5、LWT-10大于未检出者(P<0.001),外侧璧骨性血管检出者SW-10小于未检出者(P<0.001)。结论:LWT、SW、角度A、PNR及DPA可能对实施上颌窦底提升术提出挑战,应仔细评估这些解剖结构。

Objective:To analyze the bone anatomy of maxillary first molar(M1)by CBCT.Methods:The current retrospective study included 548 maxillary sinus CBCT images.Parameters such as maxillary sinus lateral wall thickness(LWT)and maxillary sinus width(SW)at 5 mm(LWT-5,SW-5)and 10 mm(LWT-10,SW-10)height levels from the sinus floor,angle A,palatal–nasal recess angle(PNR),and distance from the palatal-nasal recess to the alveolar crest(DPA)were subjected to statistical analysis.Results:Mean LWT-5 and LWT-10 were(1.99±1.07)mm and(2.32±1.60)mm.Mean SW-5 and SW-10 were(14.56±2.83)mm and(19.81±3.91)mm.In angle A,the group of less than 30°was 0.18%,30°-60°was 13.14%,and greater than 60°was 86.68%.In PNR,the group of less than 90°was 9.85%,and greater than or equal to 90°was 90.15%.At M1 sites,5.66%of the recesses were less than 90°and within 15 mm from the alveolar crest.The LWT-5,SW-5,and SW-10 in the male group were significantly greater than those in the female group(P<0.05).There was statistically significant difference on the LWT-5,SW-5,and DPA with respect to presence or absence of tooth(P<0.05).There was a significant association between SW-5 and age(P<0.05).There was statistically significant difference on the LWT-5,LWT-10,and SW-10 with respect to presence or absence of the alveolar antral artery canal(P<0.001).Conclusion:The LWT,SW,angle A,PNR,and DPA might present a challenge for performing sinus augmentation.These anatomic structures should be carefully evaluated.