FlexMaster镍钛器械根管预备效果研究

目的：评价机用FlexMaster镍钛器械根管预备效果。方法：选择因正畸或牙周病拔除的新鲜单根管离体牙60颗,根管弯曲度20°-40°,随机分成3组（FM组、H组、PF组）,分别使用机用FlexMaster、Hero642、ProFile镍钛器械,冠根向技术预备根管,通过数字牙片、扫描电镜和软件分析方法,观察比较根管拉直程度、安全性能、根尖偏移指数、牙本质小管开口数目、根管壁碎屑、玷污层等情况。结果：3组器械均能较好的维持弯曲根管的原有解剖形态,根管拉直程度差异无显著性。各组的根尖偏移指数均小于0.2 mm,视为无偏移发生,差异无显著性。牙本质小管开口数目在根管中1/3段FM组及H组牙多于PF组,在根管尖1/3段FM组多于H组及PF组,差异有显著性（P〈0.05）。根管中1/3段和根管尖1/3段,FM组和H组根管壁碎屑较PF组少,差异有显著性（P〈0.05）。各组根管壁总体较为清洁,绝大多数牙本质小管开放,仅有少量玷污层,玷污层记分差异无显著性。结论：FlexMaster镍钛系统安全、有效,能较好维持根管的初始形态,具有较好的根管成形能力和清理效果,值得临床推广使用。     

年轻恒前牙感染根管内血管再生的动物实验研究

目的通过建立根尖周炎模型观察年轻恒前牙根管内血管再生的组织学状况。方法选择4个半月龄杂种犬1只,建立上颌未发育完成的恒前牙根尖周炎模型,将6颗上颌恒前牙随机分组,对照组3颗采用根尖诱导成形术,实验组3颗采用根管内血管再生术。将术后1、4、8周的X线片分别与术前X线片进行对比,观察牙根继续发育及根尖炎症的愈合情况。术后8周处死动物,利用苏木精-伊红（HE）染色观察根尖闭合情况及根管内容物的构成。结果X线观察,术后1、4周,2组牙根的根尖孔大小及根尖透射区范围未见明显改变。术后8周,实验组根尖透射区范围缩窄较明显,并出现根尖孔缩窄的趋势,但管壁厚度无明显变化;而对照组根尖透射区变化不一。组织学检查,实验组管腔内可见肉芽组织,其中包含有大量的不规则的类牙本质、类牙骨质和类骨质样钙化物,钙化物以根尖部和管腔内侧壁尤为明显。对照组管腔未见软组织,根尖部有少量的硬组织沉积。结论血管再生术可促使年轻无髓恒前牙的慢性根尖周炎症消退,根管内再生的肉芽组织中有硬组织沉积。     

去髓术、根管治疗术一次法近期临床反应的观察

目的 :观察去髓术、根管治疗术一次法的近期临床反应。方法 :选择患急、慢性牙髓炎和慢性根尖周炎 80 0例 110 0个患牙 ,随机分为两组 ,对照组 5 14牙采用常规根管治疗术即两次法 ,实验组 5 86牙采用一次法进行根管充填 ,观察各组术后近期临床反应。结果 :在治疗结束 1周内 ,对照组与实验组出现严重急性反应的比例分别为前牙 5 .2 % ,5 .1% ;后牙 9.1% ,10 .0 % (P >0 .0 5 )。结论 :一次法根管充填短期内引起急性反应比例与常规根管治疗术相比无明显差别。     

刻度牙胶尖根管充填效果的X线片观察

目的：评价刻度牙胶尖在根管治疗术中根尖处的充填质量。方法：将符合根管治疗术适应证的患牙随机分为2组，每组50例。经常规开髓拔髓、根管预备后，实验组以刻度牙胶尖为主尖充填根管。对照组以常规无刻度牙胶尖充填根管。根管充填完毕摄X线牙片，钢尺测量根管充填材料距根尖孔距离。结果：实验组有34例根管充填达理想位(距根尖孔0．5～1．0mm)，占总数68％。而对照组仅18例根管充填能达理想位，占36％。结论：使用刻度牙胶尖充填根管能提高根管充填质量、简化治疗操作步骤，有利于提高临床工作效率。     

Metapex糊剂治疗乳牙有窦型慢性根尖周炎的疗效观察

目的：对比Metapex糊剂与氧化锌碘仿糊剂在作为乳牙根充材料时的近期与远期效果。方法：选取2011年3月至2013年7月就诊于我院儿童口腔科且明确诊断为有窦型慢性根尖周炎的97例（108颗乳磨牙）患儿,将其随机分为实验组与对照组,实验组55颗患牙用Metapex糊剂进行根管充填,对照组53颗乳磨牙用氧化锌碘仿糊剂根充。对比2周、1年和2年后疗效,并进行分析。结果：2周成功率实验组显著高于对照组（P<0.05）,1年成功率无显著差异（P>0.05),2年成功率实验组优于对照组（P<0.05）。结论：Metapex糊剂治疗乳牙有窦型慢性根尖周炎疗效较好,是理想的根充材料。     

手用ProTaper镍钛器械在老年人根管治疗中的临床应用

目的：比较手用ProTaper镍钛器械与手用K锉在老年人根管治疗中的临床应用研究。方法：老年患者127例,138颗患牙。其中手用ProTaper组65例,72颗患牙为实验组;手用K锉组62例,66颗患牙为对照组。结果：实验组无根管偏移、根尖阻塞、台阶形成及根尖孔敞开等根管内并发症的发生,根管的锥度及流畅度极佳。对照组有5个根管发生根尖阻塞,3个根管在根尖1/3处有台阶形成;有5个中度弯曲的根管和4个重度弯曲的根管有轻度至中度的根尖孔偏移。结论：2种器械根管预备有显著差异,ProTaper镍钛器械根管预备后维持厚根管形态和高充填质量。     

The Effect of Root Preparation Technique and Instrumentation Length on the Development of Apical Root Cracks

The purpose of this study was to compare the effects of root canal preparation techniques and instrumentation length on the development of apical root cracks. Forty extracted mandibular premolars with straight roots were randomly selected and mounted on resin blocks with simulated periodontal ligaments, and the apex was exposed. The teeth were divided into four groups of 10 teeth each for different canal preparation techniques and instrumentation lengths: group A: step-back preparation (SB) with stainless steel files (SF) using root canal length (RCL) to guide instrumentation length; group B: SB using RCL ? 1 mm; group C: crown-down preparation (CD) with Profile using RCL; and group D: CD with PF using RCL ? 1 mm. Digital images of the instrumentation sequence were compared for each tooth. Statistical analysis revealed a significant effect of instrumentation length (p < 0.05) but no significant effect of preparation technique (p > 0.05) on the development of apical cracks.     

即刻桩腔预备对三种根管预备方法预备的直根管根尖封闭性的影响

目的 研究三种不同根管预备方法根管预备、根管充填后即刺桩腔预备对直根管根尖封闭性的影响.方法 离体直单根管上前牙124个,其中120个随机平均分为3组(n=40),A组:不锈钢根管锉常规法;B组:G 型钻根管冠部预处理 不锈钢根管锉常规法;C组:手用Pr01raper镍钛根管锉冠向下法,刺余4个随机平均分为阴性对照组和阳性对照组.所有根管均用侧方加压法充填,即刻手持垂直加压器去除部分充填材料,然后P型钻桩腔预备.用染料渗透法评价各组根尖封闭能力.结果 B组G型钻根管冠部预处理 不锈钢根管锉常规法预备的根管和C组手用ProTaper镍钛根管锉冠向下法预备的根管即刻桩腔预备后,其根尖微渗漏较A组常规法预备的轻(P<0.05).结论 大锥度根管预备,根管充填后即刻桩腔预备的根尖封闭性较好.     

Apical leakage of obturated canals prepared by Er:YAG laser

The present study evaluates the degree of apical leakage in vitro after root canal preparation using Er:YAG laser irradiation followed by obturation. Twenty-four single-rooted teeth were divided into 2 groups of 12. One group served as a control and these root canals were conventionally prepared up to a #50K file. The other group was prepared by Er:YAG laser irradiation at parameters of 2 Hz and 170 to 230 mJ/pulse. After obturation the teeth were immersed in a vacuum flask containing 0.6% rhodamine for 48 h, longitudinally bisected, and observed by stereoscopy and scanning electron microscopy. The degree of apical leakage from an apical stop was measured and statistical analysis was performed. The degree of apical leakage from the teeth prepared by laser was not significantly less than that from control teeth (p > 0.01). Morphological findings showed that contact between the root canal walls and obturated materials was hermetic in both groups, but canal walls prepared by laser were rough and irregular. These results show that root canal preparation by laser does not affect apical leakage after obturation compared with leakage in canals prepared using the conventional method.     

MTA治疗成年患者根尖孔未闭合患牙的疗效评价

目的 评价无机三氧化聚合物（MTA）治疗成年患者根尖孔未闭合患牙的临床疗效。方法 选取成年患者根尖孔未闭合的前牙及前磨牙共41颗,随机分为2组,试验组21颗牙,在完成根管预备和消毒后,在手术显微镜下将MTA充填于根尖孔及根管下段,厚约3-5 mm,硬固后采用热牙胶完成根管中上段的充填;对照组20颗牙,采用氢氧化钙类根管糊剂Vitapex行根尖诱导成形术,定期复查,在根尖部有硬组织形成后完成根管治疗。记录患者就诊次数、治疗周期及治疗效果。结果 试验组术后X线片显示15颗患牙适充,6颗牙超充约0.5-2 mm,根管内充填物致密;平均就诊次数3.5次,平均治疗周期11.8 d,复查时多数患牙窦道闭合,根尖周病变明显缩小或消失,无新的暗影出现;对照组11颗患牙诱导成功,根尖有硬组织形成,9颗牙无明显根尖屏障形成,平均就诊次数6次,平均治疗周期306.8 d。结论 与根尖诱导成形术比较,MTA治疗成年患者根尖孔未闭合患牙的周期短,疗效好。     

脉冲Nd:YAG激光治疗慢性根尖周炎的临床疗效评价

目的 分析脉冲激光治疗慢性根尖周炎的临床疗效.方法 收集门诊68例慢性根尖周炎患者.其中36例常规根管预备后,采用激光辅助治疗和根向激光直接治疗的方法,另外32例则采用常规根管治疗做对照.通过患牙松动度、窦道愈合程度、咀嚼功能以及X线片骨质阴影区评价两者疗效.结果 激光治疗后有效率是88.89%,而常规根管治疗法则为62.50%.结论 脉冲激光对治疗慢性根尖周炎症有辅助作用,可以作为常规根管治疗的辅助手段.     

Dye leakage and SEM study of roots obturated with Thermafill and dentin bonding agent

Abstract— The apical seal of roots obturated with a dentin bonding agent and Thermafill with and without the use of sodium hypo-chlorite as an irrigating solution was compared by a dye leakage test. Roots obturated with Thermafill and a zinc oxide eugenol sealer were used as controls. Thirty-eight roots were prepared chemomech-anically and divided into three experimental groups. The teeth of group 1 were filled with Thermafill and the dentin bonding agent using sodium hypochlorite as the irrigant. The teeth of group 2 were filled in the same way, but saline solution was used as the irrigant. Before the root canal was filled the smear layer was removed from the root canal walls of both groups by rinsing the root canal with a 17% EDTA solution. The teeth of group 3 were filled with Thermafill and a zinc oxide eugenol sealer. The teeth were immersed in 2% methylene blue solution. The root fillings of groups 1 and 2 leaked significantly more than those of group 3. The resin-dentin-guttaper-cha interface of group 1 was observed by scanning electron microscopy and showed a typical hybrid layer. An intimate contact between resin and dentin was present in group 2, but a resin-dentin inter-diffusion zone was only occasionally observed. The use of dental adhesives and the hybrid layer formation did not improve the seal of Thermafill root canal Wings.     

Conservative endodontic treatment of teeth fractured in the middle or apical part of the root

Abstract –  According to treatment type, root-fractured teeth with pulp necrosis or exposed pulps were divided into five groups, group 1: 17 teeth in which the root canal of the coronal fragment only was filled with gutta-percha (GP); group 2: seven teeth in which the root canals of the coronal and apical fragments were both filled with GP; group 3: 19 teeth in which the coronal fragment was filled with GP and the apical fragment was surgically removed; group 4: 68 teeth where the root canal of the coronal fragment was treated with calcium hydroxide and subsequently filled with GP; and group 5: five vital teeth with root and concomitant crown fractures in which the exposed pulps were treated by partial pulpotomy. The frequency of periodontal healing was 76% in group 1, zero in group 2, 68% in group 3 and 86% in group 4. Compared with groups 1 and 2 combined, healing in group 4 was significantly more frequent. In groups 1, 2 and 4, failures occurred significantly more often in teeth showing overfilling, i.e. protrusion of GP into the space between the fragments, compared with teeth without overfilling. All five teeth in group 5 showed healing. It was concluded that root canal filling with GP of the coronal fragment only, with or without surgical removal of the apical fragment, can be successful in selected cases. Treatment of the root canal with calcium hydroxide followed by GP filling appears to be the treatment of choice in root-fractured non-vital teeth. Partial pulpotomy of exposed pulps in five teeth showed results similar to root-unfractured teeth with pulp exposure treated with this technique.     

Dye leakage and SEM study of roots obturated with Thermafill and dentin bonding agent.

The apical seal of roots obturated with a dentin bonding agent and Thermafill with and without the use of sodium hypochlorite as an irrigating solution was compared by a dye leakage test. Roots obturated with Thermafill and a zinc oxide eugenol sealer were used as controls. Thirty-eight roots were prepared chemomechanically and divided into three experimental groups. The teeth of group 1 were filled with Thermafill and the dentin bonding agent using sodium hypochlorite as the irrigant. The teeth of group 2 were filled in the same way, but saline solution was used as the irrigant. Before the root canal was filled the smear layer was removed from the root canal walls of both groups by rinsing the root canal with a 17% EDTA solution. The teeth of group 3 were filled with Thermafill and a zinc oxide eugenol sealer. The teeth were immersed in 2% methylene blue solution. The root fillings of groups 1 and 2 leaked significantly more than those of group 3. The resin-dentin-guttapercha interface of group 1 was observed by scanning electron microscopy and showed a typical hybrid layer. An intimate contact between resin and dentin was present in group 2, but a resin-dentin interdiffusion zone was only occasionally observed. The use of dental adhesives and the hybrid layer formation did not improve the seal of Thermafill root canal fillings.     

Bacterial contamination of the fitting surfaces of restorations in teeth with pulp and periapical disease: a scanning electron microscopy study

Background : The aim of this study was to evaluate the fitting surfaces of restorations in teeth with infected root canal systems and apical periodontitis to determine whether the restoration‐tooth interface is a potential pathway for bacterial penetration. Methods : Thirty clinically satisfactory restorations were sectioned and removed from teeth that had infected root canal systems and apical periodontitis. In the control group, three clinically satisfactory restorations were sectioned and removed from extracted teeth with clinically healthy pulps. In order to confirm the clinical diagnosis of a healthy pulp, histological examination was performed. All restorations were placed in 10% formalin immediately and then prepared for examination using scanning electron microscopy. The degree of bacterial contamination on each restoration was recorded as low, moderate or high. The morphotypes observed were classified as cocci, filaments, rods or spirochaetes. Results : The fitting surfaces of all restorations in both experimental and control groups showed signs of bacterial contamination. Conclusions : This study has demonstrated the presence of bacteria on the fitting surfaces of restorations that were judged to be clinically satisfactory in teeth with infected root canal systems. The restoration‐tooth interface is a potential pathway for bacteria to enter teeth and infect the root canal systems.     

3种根管糊剂根尖封闭性能的评价

目的　体外评价iRoot SP、AH Plus、Vitapex 3种根管糊剂的根尖封闭能力。方法　 离体单根管恒牙45颗,随机分为3组,每组15颗;通过染色法微渗漏实验比较3种根管糊剂的根尖封闭能力,并通过扫描电镜观察根管壁与糊剂之间的结合特征。结果　 iRoot SP与AH Plus组的微渗漏值较小且两者无统计学差异,Vitapex糊剂组的微渗漏值最大,与其他两组有统计学差异(P<0.05)。扫描电镜下不同根管封闭剂与根管壁和牙胶间均观察到空隙存在。结论　 iRoot SP和AH Plus的根管封闭性能较Vitapex糊剂更佳。     

The penetration of root canal sealers into dentinai tubules. A scanning electron microscopic study

The purpose of this study was to evaluate the effect of smear layer on penetration of four root canal sealers into dentinai tubules. Sixty-four, recently extracted, human maxillary and mandibular incisors were used. Following removal of the crowns, the pulps were extirpated and the root canals instrumented. The teeth were then divided into two groups. The teeth in the control group were irrigated with saline solution and the experimental group treated with EDTA and NaOCl. Each main group was then divided into four sub-groups and the root canals Oiled with Diaket, N2 Universal, SPAD and Forfenan as recommended by the manufacturers. The teeth were split longitudinally and examined using scanning electron microscopy. A quantitative assessment was made of sealer penetration into the dentinai tubules in the coronal, middle and apical parts of each root canal. It was observed that the smear layer obstructed the penetration of the tubules by the sealers. However, in the experimental group, the penetration into dentinai tubules was better with Diaket, N2 and SPAD, than with Forfenan (P > 0.01). It was concluded that this penetration could be affected by physical and chemical properties of root canal illing materials.     

超氧化物歧化酶对大鼠根尖周组织的作用

目的观察超氧化物歧化酶(SOD)对根尖周组织的作用,探讨其可能的作用机制。方法将60只健康Wistar大鼠随机分为3组,根管机械预备后即刻分别充填SOD和氢氧化钙(CH)以及空白封闭,分别于术后1、2、3、5、10周各处死4只;所有动物处死后拍摄根尖周X线片并制作组织学切片。结果SOD组和CH组在根管充填术后1周根尖周有轻度炎性细胞浸润,SOD组第2周及CH组第3周时无炎症细胞。SOD组和CH组根尖周间隙与正常组之间差异无显著性(P>0.05),与对照组比较阴影面积有显著差异(P<0.01)。结论SOD对正常根尖周组织刺激性较小,且能控制根尖周炎症、促进牙本质及牙骨质增生。     

In vitro endotoxin penetration of coronally unsealed endodontically treated teeth

Abstract The purpose of the study was to evaluate the penetration of bacterial endotoxin (L.P.S.) through obturated root canals. Twenty-four single-rooted teeth were instrumented in a uniform manner. The root canals of 16 teeth were obturated with gutta-percha and Roth's sealer and 8 teeth were similarly obturated but without sealer. The teeth were then divided into three groups. Group 1 – Positive control (4 teeth). Teeth obturated without sealer were used. Sticky wax was softened in an open flame and painted over the external root surface except the apical 2 mm and coronal canal orifice which were left free of the sticky wax. Group 2 – Negative control (4 teeth). Again teeth without sealer comprised the teeth in this group. However, in this group the sticky wax covered the apical area of the root and the canal orifice coronally, in addition to the rest of the root. Group 3 – Experimental (16 teeth). The teeth obturated in conjunction with sealer were used. Otherwise the teeth were treated as in group 1. The coronal root half was then hermetically sealed from the apical root half so that LPS placed coronally could move only through the obturated canal space to the apical segment. One ml of water containing 100 μg/ml endotoxin was placed in the upper chambers and pyrogen-free water in the lower chambers. The upper and lower chambers were then tested for endotoxin at different time periods up to 21 days. The upper chambers tested positive for endotoxin at all test times for all teeth. All 4 positive control teeth showed endotoxin in the lower chambers by 24 hrs. None of the 4 negative control teeth showed endotoxin in the lower chambers for the duration of the study. Five of the 16 (31.5%) experimental teeth had demonstrable L.P.S. in the lower chambers by the end of the 21 day test period. According to the results of this study, endotoxin may move through obturated root canals.     

超声根管预备和根管封闭剂对根尖微渗漏的影响

目的 了解超声根管预备和根管封闭剂对根管治疗后根尖微渗漏的影响。方法 将79颗离体牙随机分为5个实验组和2个对照组。实验组分别用超声波，回旋手机和手法备根后分别用AH plus^TM，根充I号，氧化锌糊剂作根管封闭剂并用牙胶法作侧压充填。用2％亚甲蓝浸泡1周后纵剖牙体，体视镜下观测染料渗透长度。数据行统计学分析。结果 三种备根方法中，超声备根组根尖微渗漏最少。三种根管封闭剂中，AH plus^TM组微渗漏最少。结论 超声根管预备后根充术，同时采用AH plus^TM根管封闭剂，能有效地减少根充术后微渗漏，提高根管治疗效果。