Division of Periodontology and Endodontology, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, Japan.
Division of Oral Medicine and Pathology, Department of Human Biology and Pathophysiology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, Japan.
Int Endod J. 2021 Feb;54(2):255-267. doi: 10.1111/iej.13414. Epub 2020 Oct 15.
To evaluate the efficacy of a prototype root canal dressing containing surface pre-reacted glass-ionomer (S-PRG) fillers on repairing induced periapical lesions in a rat model. Calcium hydroxide [Ca(OH) ] was applied as a comparison in the healing process.
The pulp chambers of the maxillary first molars in 64 male Wistar rats aged 16 weeks were opened to induce periapical lesions. After 28 days, the mesial canal of each tooth was prepared, irrigated with 2.5% sodium hypochlorite only (control group: irrigation) or followed by the respective dressing [Ca(OH) group, irrigation + Ca(OH) ; S-PRG group, irrigation + S-PRG] and restored with composite resin for 3 or 7 days (10/group). Four rats with healthy molars were used as blank controls. Descriptive analysis of the periapical radiographs, haematoxylin and eosin staining and immunohistochemical observation was performed 3 and 7 days after treatment. The periapical grey value, CD68 macrophages and osteoclasts (cathepsin-K) were quantified and statistically analysed with Tukey's honest significant difference test. A significant difference was achieved when P values were <0.05.
S-PRG and Ca(OH) dressings were associated with increased periapical grey values and inhibited osteoclast activity at 3 and 7 days; a significant difference in radiographic results and the number of osteoclasts was obtained at 3 and 7 days compared with the control group (P < 0.05). Reparative tissue was observed histologically in the space of the periapical resorbed necrotic area after S-PRG and Ca(OH) treatment for 3 and 7 days. The number of macrophages was significantly decreased at 3 and 7 days in the S-PRG and Ca(OH) specimens when compared with the controls (P < 0.05).
In a rat experimental model, the S-PRG root canal dressing was comparable to Ca(OH) in promoting the healing of experimentally induced periapical lesions. S-PRG paste has the potential to be used as an alternative intracanal dressing in teeth with apical periodontitis.
评估一种含有表面预反应玻璃离子（S-PRG）填料的原型根管封闭剂在大鼠模型中修复诱导性根尖病变的疗效。在愈合过程中，应用氢氧化钙（Ca(OH) ）作为对照。
在 16 周龄雄性 Wistar 大鼠的上颌第一磨牙牙髓室中打开牙髓，以诱导根尖病变。28 天后，每颗牙齿的近中根管均进行制备，仅用 2.5%次氯酸钠冲洗（对照组：冲洗）或随后分别用相应的封闭剂[Ca(OH) 组，冲洗+Ca(OH) ；S-PRG 组，冲洗+S-PRG]处理，并用复合树脂修复 3 或 7 天（每组 10 只）。4 只健康磨牙的大鼠作为空白对照。在治疗后 3 天和 7 天，对根尖 X 线片、苏木精和伊红染色及免疫组织化学观察进行描述性分析。用 Tukey 诚实显著差异检验对根尖灰度值、CD68 巨噬细胞和破骨细胞（组织蛋白酶-K）进行定量和统计学分析。当 P 值<0.05 时，差异具有统计学意义。
S-PRG 和 Ca(OH) 封闭剂与根尖灰度值增加和破骨细胞活性抑制相关，在 3 天和 7 天的影像学结果和破骨细胞数量与对照组相比有显著差异（P<0.05）。在 S-PRG 和 Ca(OH) 治疗后 3 天和 7 天，在根尖吸收性坏死区的空间中观察到组织学修复组织。与对照组相比，S-PRG 和 Ca(OH) 标本中巨噬细胞数量在 3 天和 7 天均显著减少（P<0.05）。
在大鼠实验模型中，S-PRG 根管封闭剂与 Ca(OH) 相比，在促进实验性根尖病变愈合方面具有可比性。S-PRG 糊剂有可能成为根尖周炎牙齿的根管内封闭剂的替代物。
