【摘要】 目的体外建立细菌微渗漏模型,比较5种不同冠方充填材料的封闭性能。方法选取32颗因正畸需要拔除的单根管前磨牙,随机分为5个实验组(每组6颗)和1个阳性对照组(空管组2颗)。常规根管预备后冠方分别充填厚度为3mm的牙胶、氧化锌丁香油水门汀(ZOE)、磷酸锌水门汀(ZPC)、玻璃离子Ⅱ型水门汀(GIC)和FiltekTMZ350流动树脂。采用粪肠球菌建立两腔式细菌微渗漏模型,将模型上方有接种细菌的储室与牙体冠方连接,下方未接种细菌的储室与牙体根方连接,上下储室间由该牙体未做根管充填牙根相连,观察下方储室是否变浑浊,确定有无细菌微渗漏发生。每3天对细菌微渗漏模型上方储室进行换液,观察120天。结果第2天空管组出现细菌微渗漏,第5天牙胶组见细菌微渗漏发生,30天后ZOE、ZPC、GIC组均有细菌微渗漏发生,120天后FiltekTMZ350流动树脂组见1个模型发生细菌微渗漏,较其他各组明显减少(P<0.05)。结论 FiltekTMZ350流动树脂冠方封闭效果较好,临床上30天内未能及时进行冠修复,建议选用其作为冠方封闭材料。更多还原

【Abstract】 Objective To compare the coronal sealing ability of five different filling materials by bacterial microleakage model in vitro.Methods Thirty-two extracted for orthodontic treatment,single-rooted premolar teeth were randomly divided into five experimental groups(n = 6)and one positive control group(2unfilling teeth).After regular root canal preparation,the coronal access cavities in five experimental groups were filled with 3mm-layer of gutta-percha,zinc oxide eugenol cement,zinc phosphate cement,the Matsukaze glass ionomer and FiltekTMZ350 flowable composite,respectively.A two-chamber bacterial microleakage model using E.faecalis as microbial marker was used for evaluation of the leakage.The coronal chamber was filled with bacterial inoculum and the apical end of the root was placed in a glass bottle containing sterile brain heart infusion(BHI).The contacting area between two chambers was root canal without sealing,Leakage was recorded when turbidity was observed in the lower chamber.Fresh BHI was added into the coronal chamber in a 3-day-interval and bacterial penetration was monitored over a 120-day period.Results All positive controls leaked within 2days.At 5days teeth from gutta-percha group had evidence of leakage.At 30 days specimens filled with zinc oxide eugenol cement,zinc phosphate cement and the Matsukaze glass ionomer had evidence of leakage.Only one specimen from FiltekTMZ350 flowable composite group was found having bacterial leakage at 120days(P<0.05).Conclusion FiltekTMZ350 flowable composite is more effectively coronal sealed than the gutta-percha,zinc oxide eugenol cement,zinc phosphate cement and the Matsukaze glass ionomer.If failed to crown restoration after root canal therapy more than 30 days,we should choose FiltekTMZ350 flowable composite as the coronal filling materials rather than gutta-percha.更多还原