【作者】 柴召午；

【导师】 宋锦璘；

【作者基本信息】 重庆医科大学 ， 口腔临床医学， 2010， 硕士

【摘要】 牙周病是一种细菌慢性感染性疾病,主要表现为牙周组织破坏,导致牙齿松动、失牙等。尤其是牙周病中II度以上根分叉病变,牙周组织缺损明显,牙周袋深度增加,局部菌斑控制难度大,常规治疗手段难以治愈,常需要实施引导性组织再生术。但该手术适应症要求严格,术中操作技术性强,再生修复效果缓慢且有限,存在一定的局限性,亟待新的辅助性治疗方式的出现。作为一种安全无创手段,低强度脉冲超声波经FDA认证已应用于促骨折愈合和骨不连临床治疗中并取得了较好的疗效。此外,前期研究发现LIPUS可促进牙槽骨再生,增加新生牙槽骨骨密度和骨成熟度,提示LIPUS作为GTR术辅助手段治疗牙周病具有一定的应用潜力。本实验选用8只成年雄性Beagle犬下颌双侧第二、三、四前磨牙,采用快速去骨与不锈钢丝结扎伴以高糖高粘性饮食饲喂的方法,构建牙周II度根分叉病变模型。将犬随机分为两个时间组(处理6周和处理8周),并将每组24颗实验牙随机分为4个处理组:牙周翻瓣术组、GTR(Bio-Gide胶原膜+犬自体骨移植)术组、牙周翻瓣术+LIPUS组、LIPUS联合GTR(Bio-Gide胶原膜+犬自体骨移植)术组,并且一只犬同一侧如有一颗实验牙选为应用LIPUS辐照后,同侧其他实验牙均不再选入非LIPUS辐照组,以避免LIPUS对邻近组织的影响。LIPUS参数为:ISATA 30mW/cm2或透过胶原膜后强度为30mW/cm2,频率1.5MHz,调制信号波宽200μs,重复率1KHz、20min/d。于处理6周和8周各选取2个处理组对牙周袋内细菌总量和目前公认的牙周致病菌—牙龈卟啉单胞菌,进行实时荧光定量PCR检测。建模8周后牙周袋加深、附着丧失明显、探诊出血,实时荧光定量PCR检测显示建模后牙周细菌总量和P.g数量均较建模前增加,具有统计学差异(P<0.05),证实了构建模型牙周袋内存在与人牙周病相似的致病菌,初步验证了模型构建的合理性,为进行LIPUS联合GTR术对牙周病组织修复作用的研究提供了良好的实验平台。牙周临床指标检查结果:GTR术处理组(包括单纯GTR组和LIPUS联合GTR组)较非GTR组牙周袋深度减少,附着丧失量减少,龈沟出血指数好转,具有统计学差异(P<0.05),但LIPUS辐照组与非LIPUS辐照组间无明显统计学差异,处理6周与处理8周也无明显统计学差异。实时荧光定量PCR结果:牙周细菌总量和P.g数量较治疗前减少,但各处理组间以及处理6周与8周无明显差别。提示LIPUS与GTR术联合,可能不增加局部致病菌,具有安全性。但对P.g是否具有抑制作用以及对其他牙周致病菌作用如何,需要进一步的研究。组织学定性观察结果:GTR术处理组牙周恢复状况良好,牙槽骨修复再生明显,形成牙周新附着; LIPUS联合GTR处理组,组织学观察可见新生牙骨质及大量牙槽骨增生修复,炎症细胞浸润较少,骨成熟度和骨密度较GTR组高,并出现了较完整的修复性牙周膜。Micro-CT检测结果:二维测量结果,相同处理时间, GTR处理组和GTR+LIPUS辐照组新生牙槽骨高度较非GTR处理组明显增加,牙根暴露高度较低,具有统计学差异(P<0.05);GTR+LIPUS辐照组较单纯GTR术处理组牙槽骨高度增加,牙根暴露高度降低,LIPUS辐照组较牙周翻瓣术组牙槽骨高度增加、牙根暴露高度降低,具有统计学差异(P<0.05);处理6周和8周组间测量指标无统计学差异(P>0.05)。三维测量结果,相同处理时间,GTR处理组和GTR+LIPUS辐照组BV、BS、Tb.N较非GTR处理组明显增大,GTR+LIPUS辐照组BV、BS、Tb.N较GTR处理组大,LIPUS辐照组BV、BS、Tb.N较牙周翻瓣术组大,具有统计学差异(P<0.05),Tb.Th值各组间无统计学差异(P>0.05);Tb.N值相同处理组处理8周较6周增大,其他各参数不同处理时间无统计学差异(P>0.05)。综上所述,本研究发现单纯LIPUS辐照可能增加新生牙槽骨骨小梁数量、体积和面积;LIPUS与GTR术联合不增加局部P.g数量,可提高GTR术修复牙槽骨能力,增大新生牙槽骨密度、体积,增加骨成熟度,组织学切片观察提示LIPUS还可能具有促进牙骨质和牙周膜修复,以及减轻局部组织炎症细胞浸润的作用。这提示一定参数的LIPUS(ISATA 30mW/cm2或透过胶原膜后强度为30mW/cm2,频率1.5MHz,调制信号波宽200μs,重复率1KHz、20min/d)作为GTR治疗II度根分叉病变的辅助手段具有潜在的临床应用前景,但辐照时间尚需进一步研究确定。更多还原

【Abstract】 Paradentosis is a chronic bacterial infectious disease. It mainly shows destruction of periodontal tissue, leading to tooth depression and missing teeth,etc.In particular,Guided Tissue Regeneration (GTR) was needed if there were periodontal tissue defecting evidences ,depth of pocket (PD) deepened , local bacteria plaque controlled difficult。Conventional treatment was difficult to cure in the periodontal disease of root bifurcation more than degreeⅡ. However, this surgery had some limitations,such as strict indications,highly technical operation in surgery,slow and limited effects in regenerative repair. So a new complementary therapy is needed to be digged out.As a safe and non-invasive treatment,LIPUS (Low Intensity Pulsed Ultrasound), certificated by the FDA,plays a significant role in promotion of fracture healing and treatment of bone nonunion. In addition,preliminary study found that LIPUS could promote the regeneration of alveolar bone and increase the optical density and paturity of the alveolar bone. It prompted that LIPUS as adjunct treatment of GTR surgery in paradentosis treatment would be used in potential application.Objects of this study were the bilateral mandibular third and fourth premolars of 8 adult male Beagle dogs. We established the periodontal disease of root bifurcation degreeⅡmodels by removing alveolar bone rapidly,ligating teeth using stainless steel silk and feeding them with high sugar and high viscosity .The dogs were randomly selected into 2 time groups(6 weeks control group and 8 weeks control group ). In each group,the number of the teeth was 24. They were randomly selected into 4 groups,which were periodontal flap surgery group , GTR(Bio-Gide collagen membrane+canine autologous bone graft)surgery group,periodontal flap surgery +LIPUS group , LIPUS joint GTR(Bio-Gide collagen membrane+canine autologous bone graft)surgery group. In this experiment,on the dog ’s same side,if a tooth had been selected as the experimental one after LIPUS irradiation, ipsilateral other experimental teeth were not elected to non-LIPUS exposure group. The aim of this was to avoid the adjacent tissue of LIPUS.For 6 weeks and 8 weeks treatment,2 control groups were selected from each time groups. The real-time fluorescence quantitative PCR detection had been done about the number of total bacteria of periodontal pocket and porphyromonas gingivalis - the periodontal pathogens which were accepted on the currently.Eight weeks after the model was established,it showed that depth of pocket (PD) deepened and attachment loss(AL) became apparent. The real-time fluorescence quantitative PCR detection showed that the number of total bacteria of periodontal tissue and P. g had increased more than the former model. There were significant differences(P < 0.05). So it confirmed the similarity of the pathogenic bacteria between building model’s periodontal pocket and paradentosis of human and the rationality of the building model. It offered a good platform for the study of the effect of Low-intensity pulsed ultrasound united GTR technique on promoting periodontal tissue repair.Clinical index of periodontal examination results showed that the control groups of GTR—Simple GTR And LIPUS United GTR had better results than the control groups of no-GTR. It shows that depth of pocket (PD),AL and sulcus bleeding index(SBI) had grown down. There were significant differences(P<0. 05). But there were no significant differences (P<0.05) between the groups of LIPUS irradiation and non-LIPUS irradiation. The same between the groups of 6 weeks controlled and 8 weeks controlled.There were no significant differences among interclass and between the groups of 6 weeks controlled and 8 weeks controlled prompted that LIPUS united GTR surgery was safe because it may not increase the local pathogen. But it required further study in whether having the effect of inhibition to P.g and what were the effect of the other periodontal pathogenic bacteria.The result of histologic qualitative observation showed a good periodontal restoration in GTR surgery group. The repair of alveolar bone regeneration was significant. The new periodontal attachment formated. In the LIPUS united GTR surgery group,we could see the proliferation of new cementum and the repair of alveolar bone. We also saw less infiltration of inflammatory cells.It was higher than the group of GTR in bone paturity and bone density. Complete prothetic peridental membrane had been found.Micro-CT test results showed that the new alveolar bones’ height of GTR group and GTR+LIPUS GTR+LIPUS irradiation group were higher than the group of non-GTR group from two-dimensional measurements in the same processing time,The root exposure was relatively low,There were significant differences(P<0. 05).The new alveolar bones’ height of LIPUS irradiation group was higher than the simple GTR group. The root exposure became lower. The new alveolar bones’ height of LIPUS irradiation group was higher than the periodontal flap surgery group. The root exposure became lower. There were significant differences(P<0.05). There were no significant differences in measure index between the group of 6 weeks and 8 weeks( P > 0.05 ) . From three-dimensional measurements in the same processing time,BV、BS、Tb. N of the GTR group and GTR+LIPUS irradiation group were higher than the group of non-GTR. BV、BS、Tb. N of the GTR+LIPUS irradiation group were higher than the group of GTR. BV、BS、Tb. N of the LIPUS irradiation group were higher than the periodontal flap surgery group. There were significant differences(P<0. 05). There were no significant differences among groups about Tb. Th. (P>0. 05). The Tb. N of 8 weeks was higher than 6 weeks in the same control group. There were no significant differences for other parameters in different time(P>0. 05).In summary, this study found that simple LIPUS irradiation might increase the number,volume and area of new alveolar bone trabeculae.It could improve the repair ability of GTR surgery to alveolar bone and increase the optical density and paturity of the alveolar bone if LIPUS united GTR surgery did not increase the number of local P. g.Observing the histological slices,we can see that LIPUS may have the effect of prompting cementum and periodontal ligament repair and reducing the local tissue inflammatory cells infiltration. It suggests that certain parameters LIPUS as the adjunct therapy to GTR surgery has potential clinical application prospects in treating root bifurcation degree Ⅱ.更多还原