Department of Endodontics, Prosthodontics, and Operative Dentistry, Baltimore College of Dental Surgery, University of Maryland, Baltimore, MD 21250, USA.
Int Endod J. 2010 Mar;43(3):218-25. doi: 10.1111/j.1365-2591.2009.01661.x.
To determine whether patient age contributed to the fracture resistance of teeth subjected to root canal treatment and post placement.
Forty-five single-rooted, single-canal human teeth were mounted, instrumented, obturated and prepared for a post. The teeth were divided into young (18 < or = age < or = 35) and old (60 < or = age) groups and subjected to cyclic loading until fracture; those reaching 200,000 cycles without undergoing failure were then subjected to static loading to fracture. Statistical differences between groups were examined using one-way anovas, and correlations were identified using Pearson's r; significance was established at P < or = 0.05.
There was no significant difference between the two age groups in terms of the number of cycles to fracture (P > 0.05) or the load to fracture (P > 0.05). However, there was a significant correlation (P < or = 0.05) between the root fracture resistance and individual age, indicating that the susceptibility to root fracture increases significantly with increasing patient age. Also, the dentine thickness of roots that fractured was significantly less than those that did not (P = 0.04).
Vertical root fracture of teeth receiving root canal treatment with posts is more likely to occur in the teeth of older patients (60+) and particularly in those with low dentine thickness.
确定患者年龄是否会影响根管治疗和桩核修复后牙齿的抗折能力。
将 45 颗单根单根管的人离体牙进行根管预备、充填、桩核预备，然后根据年龄分为年轻组（18≤年龄≤35 岁）和老年组（60≤年龄）。对两组牙进行循环加载直至折断；对达到 20 万次循环但未发生折断的牙再进行静态加载至折断。采用单因素方差分析比较两组间差异，用 Pearson 相关分析检验相关性，P 值取 0.05。
年轻组和老年组牙的循环加载至折断的次数（P>0.05）和加载至折断的力（P>0.05）均无统计学差异。但根折阻力与个体年龄呈显著相关（P<0.05），提示患者年龄越大，根折的易感性越高。另外，发生根折的牙的牙本质厚度显著小于未发生根折的牙（P=0.04）。
根管治疗后加桩核修复的牙更易发生垂直根折，尤其在老年患者（60 岁以上）和牙本质厚度较低的牙中更易发生。
