根管预备对感染根管形成根尖生物膜影响的体外研究
发布时间：2018-08-17 10:19
【摘要】：牙髓根尖周病是一类主要由细菌感染引起的、发生于牙髓及根尖周围组织的炎症性疾病，是口腔常见多发病，占口腔内科门诊的60%。根管治疗术是保存患牙，治疗牙髓根尖周病的首选方法。目前根管治疗的成功率为68~85%。根管治疗失败主要表现为难治性根尖周炎和根管治疗后疾病，而根尖生物膜被认为是导致难治性根尖周炎和根管治疗后疾病的主要原因。 目前较多的学者研究了根尖生物膜的结构组成、来源，根尖生物膜来源于感染根管已达成共识，但对于感染根管形成根尖周炎及根尖生物膜机制的研究甚少，是否与拔髓、根管预备有关，尚无定论。根尖周标本的采集方法主要依靠拔除患牙和根尖外科手术，但是能通过这两种方法取材的病例有限，限制了对上述问题的研究。因此本实验拟建立根管-根尖周复合体体外模型，从体外研究根管预备对感染根管形成根尖生物膜的影响，以期指导临床治疗。 目的： 1.建立根管-根尖周复合体体外模型。 2.体外研究根管预备对感染根管形成根尖生物膜的影响。 方法： 1.将因正畸减数拔除的健康单根前磨牙密封于盛有LB固体培养基的无菌小瓶内，使牙根的根尖1/3置于培养基中，制备成根管-根尖周复合体体外模型25个。建模后即刻随机抽取5个模型通过PCR技术检测根尖周有无细菌。将余下的20个模型随机分为对照组（n=10）及实验组（n=10），实验组做开髓处理，对照组不做任何处理。自然放置于空气中，在建模后21d检测根管内和根尖周有无细菌，及根尖周内毒素（终点显色法）。 2.按照上述方法制作根管-根尖周复合体体外模型（n=115）。于建模后即刻随机抽取5个模型通过PCR技术检测根尖周有无细菌。将余下的110个模型随机分为对照组（n=25）和实验组（n=85），对照组不做处理，实验组离体牙开髓，模型暴露于空气中21天。实验组随机抽取5个模型以检测根管内有无细菌存在，确定已形成感染根管；对照组随机抽取5个模型以检测根尖周有无细菌，以确定模型的封闭效果。将实验组余下的80个模型分为4组。第1组不做处理，第2组拔髓，第3组按离体牙工作长度预备根管，第4组超出根尖孔预备根管。根管预备后，所有模型均放置于空气中。根管预备后即刻、7d、14d、21d用PCR检测根尖周有无细菌，若检测到细菌则使用扫描电子显微镜观察离体牙根尖外表面有无根尖生物膜形成；根管预备后即刻、7d、21d用终点显色法检测根尖周内毒素含量。 结果： 1.在建模后21d，实验组根管内检测到细菌，对照组根管内未检测到细菌，而所有模型根尖区均未检测到细菌；实验组根尖周内毒素含量增加,与对照组比较，经统计学分析差异有统计学意义（P0.01）。 2.根管预备后即刻、7d、14d，根尖周均未检测到细菌；根管预备后21d，，第3组和第4组根尖周检测到细菌，在离体牙根尖外表面通过扫描电镜观察到生物膜的存在。与第1组相比，预备后即刻，第2组根尖周内毒素含量的差异无统计学意义（P0.05）；而第3组和第4组，根尖周内毒素含量减少，第4组减少更显著，经统计学分析差异有统计学意义(P0.01)。预备后7天、21天，与第1组相比，第2组根尖周内毒素含量的差异无统计学意义；第3组和第4组根尖周内毒素含量增加显著，第4组增加更显著，经统计学分析差异有统计学意义（P0.01）。 结论： 1.成功建立根管-根尖周复合体体外模型。不干扰感染根管时，感染根管内的细菌不易到达根尖周，而感染根管内的细菌首先是通过分泌的内毒素等致病因子到达根尖周引起根尖周炎。 2.全长预备或者超出根尖孔预备根管比只拔髓更容易导致感染根管内的细菌扩散至根尖周，且根尖周的内毒素含量增加更显著。
[Abstract]:Periodontal disease is a kind of inflammatory disease mainly caused by bacterial infection. It occurs in the pulp and periapical tissues. It is a common oral disease, accounting for 60% of the outpatient department of oral medicine. Refractory periapical periodontitis and disease after root canal therapy are the main causes of refractory periapical periodontitis and disease after root canal therapy.
At present, many scholars have studied the structure and composition of the apical biofilm. The origin of the apical biofilm is from the infected root canal. There is a consensus that the apical biofilm originates from the infected root canal. However, little research has been done on the mechanism of periapical inflammation and biofilm formation in the infected root canal. In order to guide the clinical treatment, a root canal-periapical complex model was established to study the effect of root canal preparation on the formation of apical biofilm in vitro.
Objective:
1. to establish an in vitro model of root canal periapical complex.
2. the effect of root canal preparation on root canal biofilm formation was studied in vitro.
Method:
1. The healthy single premolar extracted by orthodontic subtraction was sealed in a sterile vial containing LB solid medium. One third of the root tip was placed in the culture medium. 25 in vitro models of the root canal-periapical complex were prepared. Five models were randomly selected to detect the presence or absence of bacteria in the periapical zone immediately after modeling. The machine was divided into control group (n = 10) and experimental group (n = 10). The experimental group was treated with pulpotomy, and the control group was not treated with any treatment.
2. In vitro model of root canal-periapical complex (n=115) was made according to the above method. Five models were randomly selected to detect bacteria around the apex by PCR immediately after modeling. The remaining 110 models were randomly divided into control group (n=25) and experimental group (n=85). The control group was not treated, the experimental group was pulp-opening, and the model was exposed to air 21. The experimental group was randomly divided into four groups: the first group was not treated, the second group was pulped, and the third group was treated according to the isolated teeth. After root canal preparation, all the models were placed in the air. The bacteria around the apex were detected by PCR immediately, 7 days, 14 days and 21 days after root canal preparation. If bacteria were detected, the apical biofilm formation was observed by scanning electron microscope. 7d and 21d were used to detect endotoxin content in periapical by terminal color test.
Result:
1. Bacteria were detected in the root canals of the experimental group and the control group 21 days after the model was established. Bacteria were not detected in the root canals of the control group, but not in all the apical regions of the model.
2. Bacteria were not detected in the periapical area immediately after root canal preparation, 7 days and 14 days, and bacteria were detected in the periapical area of the third and fourth groups 21 days after root canal preparation, and biofilm was observed on the external surface of the root apex in vitro by scanning electron microscope. There was no significant difference in endotoxin content between the third group and the fourth group, especially in the fourth group (P 0.01). The difference was statistically significant (P0.01).
Conclusion:
1. Successful establishment of an in vitro model of the root canal-periapical complex. Without interfering with the infected root canals, the bacteria in the infected root canals are not easy to reach the periapical periodontitis, but the bacteria in the infected root canals reach the periapical periodontitis by secreting endotoxins and other pathogenic factors.
2. The bacteria in the infected root canals were more likely to spread to the periapical zone and the endotoxin content in the periapical zone increased more significantly than that in the pulp extraction alone.
【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R781.05
[Abstract]:Periodontal disease is a kind of inflammatory disease mainly caused by bacterial infection. It occurs in the pulp and periapical tissues. It is a common oral disease, accounting for 60% of the outpatient department of oral medicine. Refractory periapical periodontitis and disease after root canal therapy are the main causes of refractory periapical periodontitis and disease after root canal therapy.
At present, many scholars have studied the structure and composition of the apical biofilm. The origin of the apical biofilm is from the infected root canal. There is a consensus that the apical biofilm originates from the infected root canal. However, little research has been done on the mechanism of periapical inflammation and biofilm formation in the infected root canal. In order to guide the clinical treatment, a root canal-periapical complex model was established to study the effect of root canal preparation on the formation of apical biofilm in vitro.
Objective:
1. to establish an in vitro model of root canal periapical complex.
2. the effect of root canal preparation on root canal biofilm formation was studied in vitro.
Method:
1. The healthy single premolar extracted by orthodontic subtraction was sealed in a sterile vial containing LB solid medium. One third of the root tip was placed in the culture medium. 25 in vitro models of the root canal-periapical complex were prepared. Five models were randomly selected to detect the presence or absence of bacteria in the periapical zone immediately after modeling. The machine was divided into control group (n = 10) and experimental group (n = 10). The experimental group was treated with pulpotomy, and the control group was not treated with any treatment.
2. In vitro model of root canal-periapical complex (n=115) was made according to the above method. Five models were randomly selected to detect bacteria around the apex by PCR immediately after modeling. The remaining 110 models were randomly divided into control group (n=25) and experimental group (n=85). The control group was not treated, the experimental group was pulp-opening, and the model was exposed to air 21. The experimental group was randomly divided into four groups: the first group was not treated, the second group was pulped, and the third group was treated according to the isolated teeth. After root canal preparation, all the models were placed in the air. The bacteria around the apex were detected by PCR immediately, 7 days, 14 days and 21 days after root canal preparation. If bacteria were detected, the apical biofilm formation was observed by scanning electron microscope. 7d and 21d were used to detect endotoxin content in periapical by terminal color test.
Result:
1. Bacteria were detected in the root canals of the experimental group and the control group 21 days after the model was established. Bacteria were not detected in the root canals of the control group, but not in all the apical regions of the model.
2. Bacteria were not detected in the periapical area immediately after root canal preparation, 7 days and 14 days, and bacteria were detected in the periapical area of the third and fourth groups 21 days after root canal preparation, and biofilm was observed on the external surface of the root apex in vitro by scanning electron microscope. There was no significant difference in endotoxin content between the third group and the fourth group, especially in the fourth group (P 0.01). The difference was statistically significant (P0.01).
Conclusion:
1. Successful establishment of an in vitro model of the root canal-periapical complex. Without interfering with the infected root canals, the bacteria in the infected root canals are not easy to reach the periapical periodontitis, but the bacteria in the infected root canals reach the periapical periodontitis by secreting endotoxins and other pathogenic factors.
2. The bacteria in the infected root canals were more likely to spread to the periapical zone and the endotoxin content in the periapical zone increased more significantly than that in the pulp extraction alone.
【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R781.05
【参考文献】
相关期刊论文 前5条
1 郭惠杰;王嘉德;;慢性根尖周炎患牙根尖外表面的细菌生物膜[J];北京大学学报(医学版);2009年05期
2 胡涛,谭红,徐玉栋;急、慢性根尖周炎患牙根管内内毒素水平的分析测定[J];华西口腔医学杂志;2004年01期
3 陈兴兴;谷苗;吕海鹏;高阳;余擎;;不同方法建立实验性狗根尖周炎模型的比较[J];口腔医学研究;2009年04期
4 邢田;梅陵宣;;牙髓炎及根尖周病患牙微生物的超微结构观察[J];现代口腔医学杂志;2009年02期
5 庄沛林;高燕;凌均h
本文编号：2187296
本文链接：https://www.wllwen.com/yixuelunwen/kouq/2187296.html
最近更新
教材专著
