辛伐他汀-胶原蛋白复合海绵用于大鼠磨牙直接盖髓的实验研究

目的 评估辛伐他汀-胶原蛋白复合海绵作为直接盖髓材料的疗效及可行性。方法 120只SD大鼠随机分成3组,即辛伐他汀-胶原蛋白海绵组（SIM组）、胶原蛋白海绵组（CS组）及氢氧化钙组（CH组）,每组40只。在每只大鼠左上颌第一磨牙咬合面开髓,分别用3种材料直接盖髓,玻璃离子充填,并设对侧上颌第一磨牙为正常对照组。在术后第1、3、7、14、28天处死大鼠后拍摄X线片、苏木精-伊红（HE）及Masson’s Thichrome染色,观察牙髓组织生物学反应及牙本质桥形成情况。结果 影像学上,CH组术后第28天见穿髓孔处有高密度阻射影且封闭穿髓孔;术后第14天和第28天,SIM组在穿髓孔处见有高密度阻射影且穿髓孔封闭;而CS组仅在穿髓孔远中见高密度钙化团块影像,但未见钙化组织将穿髓孔封闭。HE及Masson’s Thichrome染色结果显示：不同时间点,3组中观察到不同的炎症反应,CS组炎症程度最重,SIM组与CS组的炎症反应程度在术后第14、28天存在统计学差异（P<0.01）。SIM组的炎症反应程度比CH组轻,在术后第14天二者存在统计学差异（P<0.05）。与另外两组相比,SIM组修复性牙本质形成的速度更快、质量更好,在术后第14天,SIM组与CH组、CS组存在统计学差异（P<0.05）,且在术后第28天,SIM组、CH组与CS组均存在统计学差异（P<0.05）。结论 辛伐他汀-胶原蛋白复合海绵生物相容性好,促进修复性牙本质形成能力较强,作为盖髓材料具有良好的应用前景。

An experimental study of simvastatin-collagen composite sponge as a direct pulp capping material in rat molars

Objective To assess the feasibility and efficacy of simvastatin-collagen composite sponge as a novel, direct pulp capping material. Methods A total of 120 Sprague-Dawley rats were randomly divided into three groups: the simvastatin-collagen composite sponge group (SIM group), the collagen sponge group (CS group), and the Ca(OH)₂ group (CH group). An endodontic entry cavity was prepared on the occlusion of the first molar on the left maxillary of each rat. The contralateral teeth were utilized as the normal control group. The rats were experimented after 1, 3, 7, 14, and 28 days. X-ray observations were conducted and the specimens underwent hematoxylin-eosin (HE) and Masson’s Thichrome staining. Dentin bridge formations and pulpal biology reactions were evaluated histopathologically. Results X-ray results: high-density images could be observed on the pulp exposure sites in the CH group on the 28th day. In the SIM group, high-density images could be observed after 14 and 28 days, whereas in the CS group, high-density images were not observable in the exposed area. HE and Masson’s Thichrome staining results: different degrees of inflammation under the cavity were detected in the three groups at different time points. The inflammatory reaction of the CS group was the most serious. The degree of the inflammatory reaction varied significantly between the SIM and the CS groups on the 14th and 28th days (P<0.01). The inflammatory reaction in the SIM group was lighter than in the CH group. There was a statistical difference between the SIM and the CH groups on the 14th day (P<0.05). During the observation period, the SIM group induced the best and fastest formation of reparative dentin. As for dentin bridge formation, a significantly higher complete bridge rate was observed in the SIM group than in the CH and in the CS groups on the 14th day (P<0.05) and for the SIM and the CH groups compared with the CS group on the 28th day (P<0.05). Conclusion The simvastatin-collagen composite sponge exhibited satisfactory biocompatibility with the pulp tissue and promoted the formation of reparative dentin. The application of simvastatin-collagen composite sponge as a pulp-capping material has satisfactory potential.