【作者】 刘勇；

【导师】 文玲英； 轩昆；

【作者基本信息】 第四军医大学 ， 口腔临床医学， 2012， 硕士

【摘要】 牙齿完全脱位是一类涉及牙髓、牙周膜、牙槽骨和牙龈等多种组织的严重牙齿外伤。再植术是其公认的治疗方法，而脱位牙再植后，往往会出现牙根吸收等并发症，致使再植牙逐渐脱落，导致再植术失败。牙齿再植的成功基础是牙周组织的重建，而牙周组织重建的前提则是牙周膜细胞的活力和功能。人们为了提高再植术的成功，围绕着相关因素进行了大量的实验和临床研究，研究显示再植术是否成功主要受到牙齿的离体时间，离体后保存环境及再植术操作等因素的影响。其中离体时间长短和保存环境直接关系着再植牙的成功。但随着离体时间延长，根面牙周膜细胞数目究竟是以何种速率减少，以及对再植牙术后愈合形式的影响，延迟再植牙进行根面处理是否可提高其成功率的相关实验研究较少。近年来国内外学者，采用一些药物作为延迟再植牙根面处理剂取得了一定的效果，但无明确论。为了探讨完全脱位牙的不同离体时间和保存液对牙周膜细胞活力的影响，明确根面药物处理对延迟再植牙牙周愈合的作用。本研究采用0.4%台盼蓝染色法对不同离体时间和不同保存剂保存下的拔除犬牙及分离的牙周膜细胞进行检测，测定根面残余牙周膜细胞的活性并计算其存活率。还对采用蜂胶和氟化钠处理根面的延迟再植犬牙进行牙周愈合状况的组织学观察，探讨根面处理剂对再植牙牙周愈合的影响，为临床再植术的治疗提供相关实验依据。本研究分以下三个实验：实验一犬完全脱位牙不同离体时间的牙周膜细胞活力检测麻醉下拔除犬牙20颗，随机分为5组，分别室温干燥放置0min、30min、60min、120min、240min.采用全牙消化法获得牙周膜细胞，并通过0.4%台盼蓝染色法检测各组牙周膜细胞数，计算细胞存活率。经统计学分析各组实验数据差异。结果：室温干燥放置30min、60min、120min和240min后，牙周膜细胞存活率依次为33.6%、23.6%、18.5%和0.8%，而0min的牙周膜细胞存活率可达95.5%。结论：随着离体时间延长，完全脱位牙根面存活的牙周膜细胞明显减少，提示完全脱位牙干燥保存方式可造成牙周膜细胞活力迅速降低。实验二不同保存液对犬牙周膜细胞活力的作用麻醉下拔除犬牙15颗，随机分为3组，室温干燥放置30min后，分别放入牛奶、HBSS液，10%蜂胶液中浸泡2h。于各组处理完成后，采用全牙消化法获得牙周膜细胞，并通过0.4%台盼蓝染色法检测各组牙周膜细胞数，计算其存活率。经统计学分析各组实验数据差异。结果：拔后30min，经牛奶、HBSS液和10%蜂胶液中保存2小时后,牙周膜细胞均有活力，其细胞存活率依次为10%蜂胶液、HBSS液和牛奶，其中10%蜂胶液与HBSS液相比无统计学差异（P＜0.05)，但分别与牛奶组相比,均有统计学差异（P＜0.05)。结论：三种保存液可以一定程度地维持牙周细胞活力，其中10%蜂胶液和HBSS液保存犬牙牙周膜细胞活力优于牛奶液。实验三不同根面处理剂对犬延迟再植牙牙周愈合的影响麻醉下拔除犬牙24颗，随机分成4组，每组6颗牙齿，其中两组为实验组，分别在干燥放置1h并完成体外根管充填后。分别浸入20%蜂胶液和2%氟化钠液30min后再植。阳性对照组为即刻再植组，阴性对照组在体外干燥放置1h并完成根管治疗后再植。术后60d处死动物，获取标本，进行组织学观察，计算各组牙齿牙根吸收率及牙周膜愈合，炎性吸收和替代性吸收的发生率，并经统计学分析。结果：即刻再植组、20%蜂胶液组、2%氟化钠组和阴性对照组的根吸收率呈依次递增趋势，并有统计学差异（P＜0.05)。各实验组牙周愈合不同类型中，20%蜂胶液和2%氟化钠组的替代性吸收和炎性吸收率均高于即刻再植组，而低于阴性对照组，前两组间的替代性吸收率、牙周膜愈合率、炎性吸收率无统计学差异。结论：完全脱位牙延迟再植前，采用适当的药物处理可以一定程度促进牙周组织愈合，20%蜂胶液和2%氟化钠液处理延迟再植牙根面均可以促进其形成牙周膜愈合并减少炎性吸收，两者之间无明显差异。更多还原

【Abstract】 Dental avulsion is a serious traumatic injury which is involved with theperiodontal ligament, cementum, alveolar bone, gingival and pulp tissues. Thebest treatment of it is accepted as re-implantation. However, the avulsed teethare generally complicated by root resorption after replantation which make theteeth fall off. This invariably leads to the failure of tooth replantation.The success of the dental reimplant depends on the re-establishment of theperiodontal ligament, and the precondition is the function of the aliveperiodontal ligament cell. Huge amounts of experiments and clinical researcheson factors have been finished in order to increase the success rates of thereplantation. These studies have found that the important factors about thesuccess of avulsed tooth depend on the extra-oral time, storage conditions andappropriate root surface treatment. The extra-oral time and storage conditionsare the most important factors in determining the viability of the remaining PDL cells, and thus affect the success rates of the tooth re-implantation. Yet, How toreduce the number of viable PDL cells with the prolongation of the dry time?How to lead to resorption of the root of the replanted tooth?How to effects onthe healing types of replantation tooth?This kind of study is less. Propolis is aresinous hive substance produced by honeybees from products collected fromplants. The substance contains multiple biological activity material. Propolis isable to promote proliferation of the human periodontal ligament fibroblasts invitro. In dentistry, the propolis has been applied in periodontology. In dentaltraumatology, there are some studies that evaluated the use of propolis as astorage medium for avulsed teeth and root surface treatment in cases of delayedtooth replantation abroad. But the study on the use of propolis is few at home.The aim of this research is to evaluate the viability change of the PDL cellsof the avulsed teeth in different extra-oral timing and storage medium, and tostudy whether propolis could promote the periodontal healing of delayed teeth.We evaluated the viability change of the PDL cells of the avulsed dog’s teeth indifferent extra-oral timing and storage medium by0.4%Trypan Blue Stains. Wealso applied propolis in the avulsed dog’s teeth replantation. After that，Wewatch the tissue recovery of replanted tooth through sections, and analysis thefunctions of propolis on the recovery of replanted tooth, and provideexperimental basis for the treatment of tooth re-implantation. The study aredivided in three experiments as follows:Experiment one: The vitality assessment on the periodontal ligament cellsderived from the avulsed dog’s teeth in different extra-oral time.The20dog teeth were extracted under local anesthesia, after that the teethwere divided into5groups. The extracted teeth were stored in room conditionfor0,30,60,120,240min respectively. The PDL cells were isolated by direct enzymatic digestion method, and the number of them were examined by0.4%Trypan Blue Stains. The results show that the number of viable PDL cellsdecreased with the prolongation of the dry time. At0,30,60,120and240minutes, the survival rate of PDL cells was95.5%,33.6%,23.6%,18.5%and0.8%respectively. Conclusion: The number of viable PDL cells remarkablydecreased with the prolongation of the dry time.Experiment two: Comparison on PDL Cell survival of the avulsed dog’steeth in different storage mediums.The15dog teeth were extracted under local anesthesia, after that, theywere divided into3groups. The extracted teeth have been stored in roomcondition for30min, which were divided into3groups and were treated withthree storage medium for2hours, HBSS, milk and10%Propolis respectively.The above method was used for the assessment on PDL cell livability. Theresults show that the PDL cells all have vitality when the teeth stored in10%Propolis, HBSS and milk for2hours. There were no significant statisticdifferences between10%Propolis and HBSS, but there was significantdifference between milk group and the other. Conclusion: The10%Propolis andHBSS were better in maintaining PDL cell viability than milk.Experiment three: Effect of different root surface treatment on delayedtooth replantation in dogs.The24dog teeth were extracted under local anesthesia, after that they weredivided into4groups. The teeth were maintained in a dry environment for60min. And then, the pulp was extirpated and the papilla, enamel organ andperiodontal ligament were removed. The teeth were immersed in20ml of2%fluoride solution and20ml of20%propolis respectively. After30min ofimmersion in the solutions, the root canals were dried and filled with calcium hydroxide paste and the teeth were replanted. The immediately replantationgroup was the positive control. The negative control teeth were air-dried andreplanted without further treatment. The animals were euthanized60days afterreplantation. Study the resorption by observing the sections. Calculate the rootresorption rate of the replanted tooth and the rate of surface resorption，inflammatory resorption or replacement resorption. The results showed that theroot resorption rate of the20%propolis solution,2%fluoride solution and thenegative control groups increase gradually, and there were significant differentamong them(P <0.05). The negative control teeth tended to have moreinflammatory root resorption compared with those treated with fluoride orpropolis. The positive control teeth tended to have more inflammatory rootresorption compared with those treated with fluoride or propolis. However, thecomparative analysis did not reveal statistically significant differences (P>0.05)between the treatment modalities when used for delayed tooth replantation.Conclusion: Both20%propolis solution and2%fluoride solution can promotethe healing of periodontal tissue of replanted tooth and reduce the inflammatoryresorption, and there were no significant differences between them.更多还原