牙槽骨高度降低对桩核修复的上颌前磨牙抗折强度的影响  

Influence of alveolar bone heights on fracture resistance and pattern of post and core restored maxillary premolars

作　　者：罗铮[1] 张丽丽[1] 张一[1] 刘玉华[1] 徐军[1] 

机构地区：[1]北京大学口腔医学院.口腔医院修复科,北京100081

出　　处：《北京大学学报（医学版）》2014年第1期62-66,共5页Journal of Peking University:Health Sciences

摘　　要：目的:研究牙槽骨高度降低对不同桩核材料修复的上颌前磨牙抗折强度及断裂模式的影响。方法:将48颗上颌前磨牙随机分组,每组8颗分为6组。A组:纤维桩核、牙本质高度正常组;B组:镍铬桩核、牙本质高度正常组;C组:纤维桩核、牙槽骨高度降低2 mm;D组:镍铬铸造桩核、牙槽骨高度降低2 mm;E组:纤维桩核、牙槽骨高度降低4 mm;F组:镍铬桩核、牙槽骨高度降低4 mm。所有实验组均用镍铬合金铸造冠修复。修复完成后,测试各组离体牙的断裂载荷并观察其断裂模式。结果:各组断裂载荷分别为:A组:(762.49±84.91)N;B组:(794.26±72.61)N;C组:(517.69±80.30)N;D组:(543.50±62.88)N;E组:(219.91±43.20)N;F组:(196.16±41.08)N。A组和B组的断裂载荷显著高于C组和D组,后二者的断裂载荷则显著高于E组和F组。A组和B组、C组和D组以及E组和F组之间的断裂载荷差异均无统计学意义。各组断裂模式中,出现可修复根折的比例分别为:A组100.0%,B组50.0%,C组75.0%,D组12.5%,E组50.0%,F组0。结论:牙槽骨高度对桩核修复的上颌前磨牙的抗折强度有显著的影响,随着牙槽骨高度的降低,患牙的抗折强度随之降低,牙槽骨高度降低的量越大,患牙抗折强度下降的幅度也越大。牙槽骨高度对桩核冠修复的上颌前磨牙的断裂模式也有影响,牙槽骨高度越降低,断裂模式也越趋于不可修复根折的模式。不同桩核材料对牙槽骨高度降低时的抗折强度没有显著影响,但纤维桩核使得断裂模式多为可修复根折的模式。Objective：To evaluate the influence of different alveolar bone heights on fracture resistance and pattern of post and core restored maxillary premolars. Methods： Forty-eight maxillary premolars were randomly divided into 6 groups （8 teeth in each group） for different alveolar bone heights and different post and core materials. Group A： fiber post and core and normal alveolar bone height. Group B： Ni-Cr cast post and core and normal alveolar bone height. Group C： fiber post and core with 2 mm alveolar bone height reduction. Group D： Ni-Cr cast post and core with 2 mm alveolar bone height reduction. Group E： fiber post and core with 4 mm alveolar bone height reduction. Group F： Ni-Cr cast post and core with 4 mm alveolar bone height reduction. All of the teeth were restored with Ni-Cr cast crowns. Fracture resistances were tested and the failure modes were examined. Results： The mean fracture resistances were （762.49± 84.91） N for group A, （794.26± 72.61 ） N for group B, （517.69 ±80.30） N for group C, （543.50 ±62.88） N for group D, （219.91±43.20） N for group E, and （196.16 ±41.08） N for group F. The ratios of favorable fractures were 100.0% for group A, 37.5% for group B, 75.0% for group C, 12.5% for group D, 50.0% for group E, and 0 for group F. Conclu- sion：The alveolar bone height has a significant impact on fracture resistance and modes of post and core restored maxillary premolars. With the reduction of alveolar bone height, the fracture decreases and the fracture mode tends to be unfavorable.

关 键 词：双尖牙 桩核技术 牙折断 牙修复体 牙槽骨 

分 类 号：R783.3[医药卫生—口腔医学]