Dental Research Center, Tehran University of Medical Sciences, Tehran, Iran.
Int Endod J. 2012 Jan;45(1):26-34. doi: 10.1111/j.1365-2591.2011.01943.x. Epub 2011 Sep 8.
To evaluate the effects of apatite precipitation on the biocompatibility and hard tissue induction properties of white mineral trioxide aggregate (WMTA) in a dental pulp model.
Pulp exposures were created on the axial walls of 32 sound canine teeth of eight dogs. Four additional sound teeth served as controls. The pulps were capped either with WMTA or apatite derivatives [biomimetic carbonated apatite (BCAp)] in the interaction of WMTA with a synthetic tissue fluid and restored with zinc oxide-eugenol cement. After 7 and 70 days, the animals were killed, and the histological specimens taken from the teeth were stained with haematoxylin and eosin for histomorphological evaluation. The Brown and Brenn technique was employed to stain bacteria. The data were subjected to nonparametric Kruskall-Wallis analysis and Mann-Whitney U_tests.
Biomimetic carbonated apatite did not induce hard tissue bridge formation. WMTA performed significantly better than BCAp in this respect at both periods (P < 0.05). BCAp was associated with a significantly greater inflammatory response as compared with WMTA after 7 days (P < 0.05). Both materials were associated with similar reactions after 70 days (P >0.05).
White mineral trioxide aggregate induced hard tissue formation via a mechanism other than that postulated via apatite formation.
评估磷灰石沉淀对牙髓模型中白色矿物三氧化物聚合体（WMTA）生物相容性和硬组织诱导特性的影响。
在 8 只狗的 32 颗健康犬齿的轴壁上制作牙髓暴露。另外 4 颗健康牙齿作为对照。牙髓分别用 WMTA 或磷灰石衍生物（仿生碳酸化磷灰石，BCAp）覆盖，在 WMTA 与合成组织液相互作用下，并用氧化锌丁香酚水泥修复。7 天和 70 天后，处死动物，从牙齿中取出组织学标本，用苏木精和伊红染色进行组织形态学评价。采用 Brown 和 Brenn 技术对细菌进行染色。数据采用非参数 Kruskal-Wallis 分析和 Mann-Whitney U 检验。
仿生碳酸化磷灰石未诱导硬组织桥形成。在这两个时期，WMTA 的表现均明显优于 BCAp（P < 0.05）。与 WMTA 相比，BCAp 在 7 天时引起的炎症反应明显更大（P < 0.05）。两种材料在 70 天后的反应相似（P > 0.05）。
白色矿物三氧化物聚合体通过不同于磷灰石形成的机制诱导硬组织形成。
