Cagidiaco Maria Crysanti, García-Godoy Franklin, Vichi Alessandro, Grandini Simone, Goracci Cecilia, Ferrari Marco
School of Dental Medicine, University of Siena, Italy.
Am J Dent. 2008 Jun;21(3):179-84.
To assess whether the amount of residual coronal dentin and the placement of a prefabricated (DT Light Post) (LP) or a customized fiber post (Ever Stick Post) (ES) have a significant influence on the 3-year survival of endodontically treated premolars.
A sample of 345 patients provided six groups of 60 premolars in need of endodontic treatment. Groups were defined based on the amount of dentin left at the coronal level after endodontic treatment and before abutment build-up. Within each group teeth were randomly divided into three subgroups (n = 20). In Subgroup A, no root canal retention was provided for the coronal restoration. In Subgroups B and C, LP and ES, respectively, were placed inside the root canal. All the teeth were finally restored with a single unit metal-ceramic crown.
Data were not affected by any loss to follow-up. The overall 36-month survival rate of crowned endodontically treated premolars was 76.7%. The lowest survival rate was recorded for teeth restored without any root canal retention (62.5%). Teeth restored with LP had a survival rate higher (90.9%) than those restored with ES (76.7%). The Cox regression analysis showed that the presence of root canal retention was a significant factor for survival (P < 0.05). The decrease in failure risk was higher in teeth restored with LP (HR = 0.1; 95% CI for HR = 0.09 to 0.34; P < 0.001) than when using ES (HR = 0.5; 95% CI for HR = 0.3 to 0.7; P = 0.003). Teeth retaining one (HR = 0.3; 95% CI for HR = 0.2 to 0.7; P = 0.003), two (HR = 0.2; 95% CI for HR = 0.1 to 0.5; P < 0.001), or three coronal walls (HR = 0.1; 95% CI for HR = 0.05 to 0.3; P < 0.001) had a significantly lower failure risk than teeth deprived even of the ferrule effect. Similar failure risks existed for teeth missing all the coronal walls regardless of the presence or absence of a ferrule effect (P > 0.05). Interaction terms were not significant (P > 0.05). Post placement and the amount of residual coronal dentin affected the 3-year survival of endodontically treated premolars.
评估剩余冠部牙本质的量以及预成（DT Light桩）（LP）或定制纤维桩（Ever Stick桩）（ES）的放置对根管治疗后前磨牙3年生存率是否有显著影响。
345例患者的样本提供了六组共60颗需要根管治疗的前磨牙。根据根管治疗后和基牙修复前冠部剩余牙本质的量来定义组别。在每组中，牙齿被随机分为三个亚组（n = 20）。在A亚组中，冠修复未提供根管固位。在B亚组和C亚组中，分别在根管内放置LP和ES。所有牙齿最终均用单单位金属烤瓷冠修复。
数据未受任何失访影响。根管治疗后戴冠前磨牙的总体36个月生存率为76.7%。未进行任何根管固位修复的牙齿生存率最低（62.5%）。用LP修复的牙齿生存率（9０.9%）高于用ES修复的牙齿（76.7%）。Cox回归分析表明，根管固位的存在是生存的一个重要因素（P < 0.05）。与使用ES相比，用LP修复的牙齿失败风险降低幅度更大（风险比[HR] = 0.1；HR的95%置信区间为0.09至0.34；P < 0.001）（HR = 0.5；HR的95%置信区间为0.3至0.7；P = 0.003）。保留一个（HR = 0.3；HR的95%置信区间为0.2至0.7；P = 0.003）、两个（HR = 0.2；HR的95%置信区间为0.1至0.5；P < 0.001）或三个冠壁（HR = 0.1；HR的95%置信区间为0.05至0.3；P < 0.001）的牙齿失败风险显著低于甚至没有箍效应的牙齿。无论有无箍效应，所有冠壁均缺失的牙齿失败风险相似（P > 0.05）。交互项不显著（P > 0.05）。桩的放置和剩余冠部牙本质的量影响根管治疗后前磨牙的3年生存率。
