预备弯曲根管时根管偏移的实验研究

目的：定量研究弯曲根管预备过程中根管的偏移。方法：使用不锈钢K锉按常规法预备8个弯曲人工根管，根管预备过程中对根管、根尖孔进行微距摄影，用图像分析软件Image—Pro Plus对根管的形态和位置变化进行测量、分析。结果：根管预备时随着锉号的递增，弯曲根管逐渐被拉直，表现为根管弯曲角度逐渐减小，弯曲半径、根管轮廓面积逐渐增大，根管口、根尖孔被拉开，根管壁出现3个过度切削区。结论：预备弯曲根管时，根管不同部位的偏移方向、偏移距离并不相同，掌握弯曲根管的解剖形态以及根管器械的力学性能，有助于准确估计根管偏移的大小和方向。     

联合侧向热垂直加压技术充填根管初探

目的:探索采用联合侧向热垂直加压技术充填根管以改良热连续波根充技术,通过增加根尖部的牙胶量克服该技术超充率较高,以及根尖部根管牙胶充盈率(PGFA)较低的缺点。方法:80颗离体尖牙牙根用改良双敞技术预备后,随机分为2组,分别用单纯热连续波法和侧向热垂直联合加压充填技术根充,超充样本计数;所有样本均在距根尖孔1.5mm水平截断,体视显微镜下数码拍照,计算机测定PGFA值,统计学分析。结果:实验组超充率低于对照组,差异有统计学意义(P<0.05);实验组距根尖孔1.5mm的PGFA高于对照组,差异有统计学意义(P<0.01)。结论:侧向热垂直联合加压充填技术,比单纯热连续波法具有更好的根充效果。     

The antimicrobial effect of calcium hydroxide in root canals pretreated with 5% iodine potassium iodide

Abstract— Calcium hydroxide (CH) is often used as a routine interappointment dressing during the endodontic treatment of teeth with apical periodontitis. However, it fails to consistently produce sterile root canals. The present study was set up to find out whether an antimicrobial strategy including the use of CH could be made more effective if: 1) canals were pretreated with 5% iodine potassium iodide (IPI), and 2) the dressing period was extended up to 2 months. Fifty human teeth, with radiographically verified apical periodontitis, were microbiologically sampled. After chemomechanical preparation the canals were pretreated with IPI for 3–7 days. Teeth where microorganisms persisted were then treated with CH for 2 months. Following instrumentation and dressing with IPI, 43 bacterial strains were recovered in 22 of the teeth. Samples obtained after the CH dressing period disclosed growth of 13 facultative and two strict anaerobic strains in 10 teeth. Enterococcus faecalis was identified in two specimens. In conclusion, the present study gave no evidence for an increased antimicrobial effect of CH if it was left for longer periods in the root canal. Although pretreatment with IPI from a quantitative point of view did not seem to add antimicrobial power, it might reduce the frequency of persisting strains of E. faecalis .     

钙化根管的根管显微镜治疗

目的:探讨应用根管显微镜治疗钙化根管的方法,并对其疗效进行评价.方法:因根管钙化进行根管治疗的患牙33个,在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合进行治疗,记录预备时间,术后1周进行根管充填,半年后复查并进行疗效评价.结果:根管显微镜下钙化根管的治疗成功率为88.9%,平均每根根管耗时25.8 min.结论:在根管显微镜引导下,将超声预备、手动NiTi器械预备以及EDTA化学预备相结合可提高钙化根管治疗的成功率.     

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目的探讨前牙钙化根管治疗的可行性。方法2003年1月至2005年12月,对郑州市中医院口腔科收集的前牙钙化根管患者22例,通过寻找根管口,行根管治疗术,进行术前、术后X线片观察研究。结果20例患者顺利完成根管治疗术,2例因根管完全钙化行根尖手术。结论前牙钙化根管的治疗关键在于根管口的寻找,并进行常规根管治疗术,避免根尖手术或牙拔除术。     

Observations of acoustic streaming fields around an oscillating ultrasonic file

Abstract The steady acoustic streaming generated around straight and precurved oscillating ultrasonic files driven by the Piezon-Master 400 unit was examined in the free field and in small channels using a stereomicroscope. In addition, the effect of file-wall contact on streaming production was also investigated. The results indicated that the ultrasonic files can generate acoustic streaming both in the free field and in the small channel. Higher velocity streaming was observed when smaller size files were employed and when the file was precurved. Light file-wall contact did not totally inhibit streaming while severe file-wall contact inhibited movement of the file and, as a result, no streaming was observed. The positions and length scales of the streaming vortices appeared to be influenced by the presence of boundaries. In the free field, two rows of vortices were situated along the sides of the file while in the small channel, the vortices were positioned above the surface of the file. These results indicated that it is possible for acoustic streaming to occur in a confined space as in a root canal provided that severe file-wall contact is avoided. It is therefore recommended that light filing or allowing the file to freely vibrate during some stage of treatment should be carried out in order to generate streaming in the root canal.     

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在美国牙髓病学专家Gutmann<牙髓病学解难>一书的开卷语中,引用了1884年一位英国牙髓病研究者的话:治疗前花一小会儿时间思考一下根尖病的病因,使我们理解欲达到成功目的所必须做的事;倘若病变来自感染牙髓的分解,那么将其清除,即可将多数病例治愈.     

根管钙化治疗的研究进展

根管钙化是牙髓病和根尖周病临床治疗中较为棘手的问题.了解各类钙化根管的治疗方法,对提高治疗成功率有重要意义.yynw文就根管钙化的原因、X线摄片技术、钙化根管口的寻找方法及临床治疗的研究现状作一综述.     

根管治疗术中的疼痛原因分析及疼痛控制

根管治疗是牙髓病及根尖周病的一种有效治疗方法,已在临床上广泛使用,然而在治疗过程中及治疗完成后患者可能会出现各种原因的疼痛。本文对根管治疗术中疼痛发生的原因进行分析,从而为临床医生采取相应的有效措施和治疗手段缓解患者痛苦提供参考。     

微焦点CT技术测定根管预备后根管偏移

目的通过微焦点CT技术建立一种新的根管偏移评价体系。方法选用树脂人工弯曲根管模型,使用手用镍钛ProTaper按照冠向下方法预备模型,并用微焦点CT扫描收集数据,运用计算机高级语言软件处理分析其截面前后中心点及面积的变化,评价ProTaper对树脂弯曲根管的预备效果,并建立关于预备前后中心点的三维模型。结果手用镍钛ProTaper预备后的根管,同一截层面积大小基本一致。通过对微焦点CT扫描数据的处理,建立起了根管预备前后根管偏移的二维和三维指标结合评价的比较体系。ProTaper对根尖段定位成形能力较好,预备前后根管偏移小。结论利用微焦点CT建立三维根管中心轴模型,可以为分析根管预备器械的成形能力提供一种新的途径。结合二维的截面面积,可以分析得出更加直观的根管预备后根管偏移情况。     

老年人部分闭锁根管的预备

目的:总结对老年人部分闭锁的根管进行根管预备的特点.方法:对50例根管闭锁需进行根管治疗的牙齿,经常规手持器械预备辅助以化学预备——乙二胺四乙酸(EDTA)液,双氧水及氯亚明反复冲洗根管,同时相应增加复诊次数,对根管进行多次预备.结果:50例患牙最终获得满意的根管预备.结论:对于老年人部分闭锁的根管,通过手持器械加化学预备多次根管扩大,可以获得满意的根管预备.     

根管治疗与根折的关系

根折是根管治疗后常见并发症。很多研究已经显示过度的根管预备,充填时对根管壁产生的应力以及治疗过程中用到的药物、试剂都会直接或间接引起牙根纵折。为了更合理地选择治疗方案,减少医源性的因素导致的根折,本文就根管治疗过程中可能增加根折易感性的因素作一综述。     

Preparation of simulated root canals using the Macfile, Canal Master U and K-Flexofile

The efficacy of three different root canal instruments in maintaining the original shape of curved canals was evaluated. Acrylic blocks were prepared to simulate canals with 40° and 60° curvature. K-Flexofiles and Macfiles were used with a step-back technique utilizing an 'in/out' filing motion. The balanced-force technique was used with Canal Master 'U' instruments. Ten 40° and 10 60° canals were prepared with each instrument. The results were evaluated using superimposed photographic slides at ×20 magnification to show the canals before and after the instrumentation. The width of the prepared canals was measured at their convex/concave point to determine the divergence of the instrumented canal shape from the original canal shape. The measurements were taken at the level of the apical foramen and 3 and 6 mm coronal to it. In this way it was possible to recognize all the defects created during the preparation of a canal. Among the tested instruments, the Macfile provoked minimal canal deviation ( P = 0.05). The Canal Master 'U' was similarly effective ( P = 0.05), but had the highest incidence of instrument fracture. The K-Flexofile demonstrated the most defects in canal preparation and canal deviation, particularly at the level of the apical foramen ( P < 0.01).     

三种牙齿工作长度测量方法的比较研究

目的:研究三种牙齿根管工作长度测量方法的符合率。方法:选取临床上需进行根管治疗术的患牙153个(358个根管),使用TRI AUTO ZX根管治疗仪确定牙齿工作长度,与X线诊断丝照相法和器械探查法进行对比,研究3种牙齿工作长度测量法的符合率。结果:电测法与X线诊断丝照相法比较,符合率为92.46%,电测法与器械探查法比较,符合率为67.88%;X线诊断丝照相法与器械探查法比较,符合率为64.53%。结论:牙齿长度电测法是一种比较准确、客观的测量牙齿工作长度的方法。     

下颌前牙根管形态的研究进展

下颌前牙多为单根单管,但根管变异亦屡见不鲜,因而遗漏根管导致下颌前牙根管治疗失败的情况时有发生。本文通过回溯国内外近年来下颌前牙根管形态的研究结果,分析了下颌前牙根管形态特点及根管变异与根管治疗效果的关系,提出几点建议,以期为临床治疗提供参考。     

3种根管糊剂的根管密封性能研究

目的比较Vitapex糊剂、AH-Plus糊剂和GuttaFlow常温流动牙胶根管充填的致密性。方法选择30颗单根管牙,随机分3组,每组10颗牙。分别用Vitapex糊剂(A组)、AH-Plus糊剂(B组)、GuttaFlow常温流动牙胶(C组)充填根管。分别对每颗牙在距根尖2、4、6、8 mm进行片切,MIAS-2000图像分析并计算各横断面的根管面积(area of canal,AC)以及其中的空隙面积百分比(perceentage of voild-filled area,PV)。记录结果,并进行统计学分析。结果各组根充材料在距离根尖相同处的根管面积(AC值)虽有所差异,但无统计学意义(P>0.05)。在距根尖2、4、6、8 mm处C组材料的PV值与其他各组均有统计学意义(P<0.05);在距根尖2、4 mm处A、B组的PV值有统计学意义(P<0.05),B、C组的PV值无统计学意义(P>0.05);在距根尖6、8 mm处3组间的PV值均有统计学意义(P<0.05)。结论 GuttaFlow常温流动牙胶和AH-Plus糊剂在距根尖不同部位均显示出较好的致密度;Vitapex糊剂的致密度欠佳。     

老年患者细小钙化根管的临床治疗

目的:探讨老年患者细小钙化根管的治疗方法和临床疗效.方法:选取老年患者中有细小或钙化根管的患牙65颗,采用乙二胺四乙酸(EDTA)溶液和小号手用K锉疏通细小根管,超声锉与EDTA、小号手用锉结合处理钙化根管,完成根管治疗并观察疗效.结果:59颗患牙的根管疏通成功并完成根管治疗,成功率为90.8%,细小根管疏通成功率为100.0%,钙化根管再通成功率为81.3%.无牙根折裂、台阶形成、根管壁侧穿或器械折断发生.结论:超声器械、EDTA、小号手用K锉相结合,可作为临床上治疗老年患者细小钙化根管的有效方法,但超声器械不宜用于根管的下段或弯曲部位.     

Effect of ultrasonic instrumentation on Bacteroides intermedius

Abstract Two physical mechanisms of ultrasound, cavitation and acoustic streaming, were investigated in an ultrasonic endodontic unit. In addition, the potential of ultrasonic instrumentation for disruption of Bacteroides intermedius was examined at various time intervals. The ultrasonic file could not generate cavitation within the recommended power settings indicated for endodontic purposes. However, there was evidence of acoustic streaming. The latter phenomenon resulted in destruction of 21.6%, 30.4% and 92.9% of test bacteria after 1, 5 and 15 min sonication respectively. It appears that ultrasonic instrumentation of root canals has little bactericidal effect.     

老年患者钙化根管的预备

目的：观察老年人根管钙化情况,总结高校社区医院对老年患者钙化根管的治疗方法。方法：选择60-72岁老年患者的148个钙化根管,在EyeMag放大镜下,分别采用低速球钻或超声器械去除髓室内钙化物, C型先锋锉蘸取Glyde凝胶进行根管疏通,术中记录根管钙化情况和疏通效果,最后完成根管预备、消毒和充填。结果：老年人钙化根管多见于上颌第一磨牙,前牙、前磨牙、磨牙疏通成功率分别为：91.67%,72.73%,60.80%,前牙组疏通成功率高于磨牙组（χ2=4.50, P＜0.05）;根管冠方1/3和根中1/3较易发生钙化,且钙化的疏通成功率明显高于根尖1/3（χ2=19.33, P＜0.05）。结论：针对老年人钙化根管的治疗,临床医生要有足够的细心、耐心和信心,灵活的综合运用现有的各种治疗器械和设备,能够取得较好的治疗效果。     

根管糊剂在ObturaⅡ充填技术中对根尖微渗漏的影响

目的:探讨在Obtura Ⅱ注射式热熔牙胶充填中,不同根管糊剂对根尖微渗漏的影响。方法:40颗单根管牙随机分为4组,采用Obtura Ⅱ注射式热熔牙胶进行根管充填,A、B、C组分别以ZOE、Vitapex、AHplus作为根管糊剂,D组未用糊剂。充填后行墨汁渗透实验,制作透明标本,使用体视显微镜和显微照相系统观测染料渗透的长度。结果:染料自根尖孔渗入根管的长度,D组最长,为4.56±2.72mm,与A、B、C组间差异均有显著性(P<0.05)。在使用糊剂的实验组中,染色线的长度由小到大依次是AHplus1.70±0.82mm、Vitapex1.87±0.56mm和ZOE2.02±0.40mm,但3组之间没有统计学差异(P>0.05)。结论:根管糊剂的使用能显著降低Obtura Ⅱ根管充填后根尖的微渗漏。