Department of Materials Science and Engineering, University of Washington, Seattle, Washington.
School of Engineering, Universidad EAFIT, Medellín, Colombia.
J Endod. 2019 Feb;45(2):189-193. doi: 10.1016/j.joen.2018.10.004.
Although the strength and toughness of dentin decrease with age, no study has explored if restorative treatments are a contributing factor.
Multiple extracted teeth were obtained from randomly selected donors and categorized according to donor age and prior root canal treatment. The microstructure and chemical composition of radicular dentin were evaluated using scanning electron microscopy and Raman spectroscopy, respectively, and the strength was evaluated in 4-point flexure to failure. Data were compared using the Student t test.
Dentin from the root canal-restored teeth exhibited significantly lower strength (P < .05) than tissue from age- and donor-matched unrestored tooth pairs. Although there was no significant difference in the mineral-to-collagen ratio between the 2 groups, dentin obtained from the root canal-treated teeth exhibited more extensive collagen cross-linking and lower tubule occlusion ratios than the unrestored tooth pairs.
There is a decrease in the strength of radicular dentin with aging, but prior root canal treatment increases the extent of degradation.
尽管牙本质的强度和韧性会随年龄增长而下降，但尚无研究探讨修复治疗是否是一个促成因素。
从随机选择的供体中获得多颗离体牙，并根据供体年龄和先前的根管治疗进行分类。使用扫描电子显微镜和拉曼光谱分别评估根管治疗牙的牙本质微观结构和化学成分，并进行四点弯曲破坏试验评估其强度。使用学生 t 检验比较数据。
根管治疗修复过的牙齿的牙本质强度明显低于年龄和供体匹配的未修复牙对（P<.05）。尽管两组的矿化胶原比值无显著差异，但与未修复牙对相比，根管治疗牙的牙本质中胶原交联更为广泛，小管封闭率更低。
牙本质的强度随年龄增长而下降，但先前的根管治疗会增加其降解程度。
