發(fā)布時(shí)間：2018-04-13 12:09

  本文選題：根尖周炎 + 根尖生物膜��； 參考：《重慶醫(yī)科大學(xué)》2017年碩士論文

【摘要】：根管治療是治療根尖周炎的首選方法,即在治療中最大程度的清除根管內(nèi)感染,并進(jìn)行嚴(yán)密的三維充填以防止再感染。少數(shù)的患牙,即使進(jìn)行了標(biāo)準(zhǔn)規(guī)范的根管治療,根尖周炎仍遷延不愈,我們通常將此稱為難治性根尖周炎。根尖生物膜被認(rèn)為是導(dǎo)致難治性根尖周炎的重要原因。對(duì)于牙周健康的患牙,根尖生物膜來源于感染根管已達(dá)成共識(shí)。但根管內(nèi)的細(xì)菌是在環(huán)境因素的誘導(dǎo)下主動(dòng)溢出根尖孔,還是受擠壓而溢出根尖孔形成根尖生物膜仍存在爭(zhēng)議。為了研究根尖生物膜的形成原因,本課題組前期實(shí)驗(yàn)進(jìn)行了體外研究,表明只有根管全長(zhǎng)預(yù)備和超預(yù)備狀態(tài)下,才在根尖周檢測(cè)到細(xì)菌及根尖生物膜。但體外實(shí)驗(yàn)忽略了機(jī)體的免疫反應(yīng)。根尖周炎的病理反應(yīng)與機(jī)體的免疫反應(yīng)密不可分,而根尖周細(xì)菌形成根尖生物膜又與根尖周的免疫炎癥反應(yīng)可能有著一定聯(lián)系。本實(shí)驗(yàn)將建立免疫抑制大鼠模型和大鼠感染根管動(dòng)物模型,對(duì)免疫正常組和免疫抑制組進(jìn)行不同長(zhǎng)度的根管預(yù)備,以觀察不同根管預(yù)備長(zhǎng)度及免疫抑制對(duì)根尖生物膜形成的影響。為臨床工作中預(yù)防難治性根尖周炎的形成提供理論依據(jù)。目的:建立感染根管大鼠模型和免疫抑制大鼠模型,探討不同根管預(yù)備長(zhǎng)度對(duì)免疫正常和免疫抑制大鼠感染根管形成根尖生物膜的影響。材料和方法1、建立免疫抑制大鼠模型:54只大鼠分為免疫正常組(n=27)和免疫抑制組(n=27)。免疫抑制組腹腔注射環(huán)磷酰胺50mg/kg,1周1次,以建立免疫抑制動(dòng)物模型。2.建立感染根管大鼠模型:免疫正常組隨機(jī)分為對(duì)照組A(n=3),實(shí)驗(yàn)組B、C、D、E(均n=6);免疫抑制組均隨機(jī)分為對(duì)照組a(n=3),實(shí)驗(yàn)組b、c、d、e(均n=6)。對(duì)照組不做處理。實(shí)驗(yàn)組雙側(cè)上頜第一磨牙均行開髓處理。開髓后髓腔暴露于口腔環(huán)境中正常飼養(yǎng)4周,以建立感染根管動(dòng)物模型。3.根管干預(yù):B、b組開髓后不做任何處理。C、c組雙側(cè)上頜第一磨牙近中根管行根管預(yù)備至根管上2/3工作長(zhǎng)度。D、d組雙側(cè)上頜第一磨牙近中根管行根管預(yù)備至全長(zhǎng)。E、e組雙側(cè)上頜第一磨牙近中根管超出根管工作長(zhǎng)度1毫米預(yù)備。根管預(yù)備后第7天和21天,每組均分別處死3只大鼠,取左側(cè)上頜第一磨牙近中牙根表面組織進(jìn)行PCR檢測(cè),取右側(cè)上頜第一磨牙近中牙根用于掃描電鏡,觀察是否形成根尖生物膜。結(jié)果:根管預(yù)備后第7天和21天,全長(zhǎng)組(D、d組)及超長(zhǎng)組(E、e組)根尖區(qū)樣本擴(kuò)增出16Sr DNA特異性引物片段,對(duì)照組(A、a組)、開髓組(B、b組)及2/3干擾組(C、c組)均未檢測(cè)到。根管預(yù)備后第7天,A、a組樣本的根尖區(qū)均可見大量膠原纖維覆蓋于牙根表面,未見暴露的牙骨質(zhì)及吸收陷窩。而B、C、D、E、b、c、d、e組近中牙根根尖區(qū)在掃描電鏡下均未觀察到細(xì)菌生物膜的存在,但根尖區(qū)牙骨質(zhì)表面暴露,牙根表面幾乎沒有膠原纖維覆蓋,并可見許多牙骨質(zhì)吸收陷窩。根管預(yù)備后第21天,E組中僅有一例樣本觀察到小范圍細(xì)菌生物膜存在,主要由桿菌組成,周圍包裹有少量無定型基質(zhì)樣物質(zhì)。其余組與根管預(yù)備后第7天一致。結(jié)論:1.成功建立免疫抑制大鼠模型和感染根管大鼠模型。2.在機(jī)體免疫機(jī)制作用下,根管全長(zhǎng)預(yù)備和超長(zhǎng)預(yù)備對(duì)細(xì)菌溢出根尖孔有促進(jìn)作用,但沒有證據(jù)表明對(duì)根尖生物膜的形成有促進(jìn)作用。
[Abstract]:Root canal therapy is the preferred method for the treatment of periapical periodontitis, namely in the treatment of the maximum removal of root canal infection, and rigorous three-dimensional filling to prevent reinfection. A few teeth, even if the Standard Specification for root canal therapy, periapical periodontitis is still persistent, we usually refer to this refractory periapical lesions. Periapical biofilm is considered to be an important cause of refractory periapical periodontitis. The periodontal health of the teeth with periapical biofilm from the infected root canal has been reached. But the root canal bacteria is induced by environmental factors under active overflow apical or by extrusion and overflow of root tip the hole formation of periapical biofilm is still controversial. In order to research on the causes of periapical biofilm, ourprevious experiments were carried out in vitro study showed that only the length of root canal preparation and preparation of super state, was detected in the periapical bacteria And periapical biofilm in vitro. But ignore the body's immune response. Closely related to pathological reaction and immune response of periapical periodontitis, and periapical periapical biofilm forming bacteria and inflammation periapical may have some contact. This experiment will establish the Immunosuppressive Model in rats and rats infected root canal the animal model of root canal preparation on immune normal group and immunosuppressed group of different length, in order to investigate the effect of different root canal length and immunosuppression on periapical biofilm formation. To provide a theoretical basis for clinical work in the prevention of the formation of refractory periapical periodontitis. Objective: to establish rat model and immune tube suppression the rat model of infected root canals of different length of the inhibitory effect of rat periapical biofilm formation of infected root canal of normal immune and immune. Materials and methods 1, the establishment of rat model of immune suppression 鍨，

本文編號(hào)：1744425