Department of Operative Dentistry and Periodontology, University School of Dental Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Int Endod J. 2010 Jun;43(6):469-77. doi: 10.1111/j.1365-2591.2010.01701.x.
To investigate the effects of endodontic treatment, post placement and ceramic restoration type on the fracture resistance of premolars.
One hundred and twenty teeth maxillary premolars were allocated to four groups (A-D; n = 30). In group A, mesio-occlusal-distal-inlays with a buccal and palatal wall of 2 mm (MOD), in group B partial onlays with palatal cusp coverage and in group C total onlays with buccal and palatal cusp coverage were prepared. Group D served as untreated controls. Groups A-C were divided into three subgroups (n = 10): (i) teeth received solely the described preparations, (ii) teeth were root filled, (iii) teeth were root filled and quartz fibre posts were placed. Teeth were restored using Computer-assisted design/computer-assisted machining-ceramic-restorations and subjected to thermo-mechanical-loading; subsequently, the buccal cusp was loaded until fracture.
Group D revealed significantly higher fracture resistance [mean (standard deviation)] [738 (272) N] compared to all other groups (P < 0.05; post hoc test Dunnett). For groups A-C, fracture resistance was significantly affected by the restoration type (P = 0.043) and endodontic treatment/post placement (P = 0.039; 2-way anova). Group A [380 (146) N] showed significantly lower fracture resistance compared to group B [470 (158) N] (P = 0.048; post hoc test Tukey). Compared to non-endodontically treated teeth [487 (120) N], root filled teeth revealed significantly lower fracture resistance [389 (171) N] (P = 0.031).
The restoration of cavities with a remaining wall thickness of 2 mm using ceramic MOD-inlays is inferior with respect to the fracture resistance compared to partial onlay restorations. Root filled teeth without post placement show lower fracture resistance compared to non-endodontically treated teeth.
研究根管治疗、桩核修复和陶瓷修复类型对上颌前磨牙抗折性能的影响。
将 120 颗上颌前磨牙随机分为 4 组（A-D；n=30）。A 组为颊腭壁 2mm 的近中-颊舌-远中嵌体（MOD），B 组为颊尖覆盖的部分高嵌体，C 组为颊尖和腭尖全覆盖的全高嵌体。D 组为未处理对照组。A-C 组又分为 3 个亚组（n=10）：（i）仅进行描述性预备的牙齿；（ii）根管治疗的牙齿；（iii）根管治疗并用石英纤维桩核修复的牙齿。使用计算机辅助设计/计算机辅助制造陶瓷修复体进行修复，并进行热机械加载；随后加载颊尖直至发生骨折。
与其他所有组相比，D 组的抗折力显著更高[平均值（标准差）] [738（272）N]（P<0.05；事后检验 Dunnett）。对于 A-C 组，修复类型（P=0.043）和根管治疗/桩核修复（P=0.039；2 因素方差分析）对抗折力有显著影响。与 B 组[470（158）N]相比，A 组[380（146）N]的抗折力显著降低（P=0.048；Tukey 事后检验）。与未经根管治疗的牙齿[487（120）N]相比，根管治疗后的牙齿[389（171）N]的抗折力显著降低（P=0.031）。
对于剩余颊腭壁厚度为 2mm 的窝洞，使用陶瓷 MOD 嵌体修复的抗折性能不如部分高嵌体修复。未进行桩核修复的根管治疗后的牙齿与未经根管治疗的牙齿相比，抗折力较低。
