热牙胶连续波根充与冷侧压根充后根尖微渗漏的研究

目的：比较不同根管预备方法下,热胶牙连续波根充与冷侧压根充术后,根尖微渗漏的情况。方法：将100颗单根离体恒牙,随机分为2组,A组50颗牙采用ProTaper预备,B组50颗牙采用不锈钢K型锉预备。根管预备完成后,A组牙齿随机分为A1组25颗牙齿,A2组25颗牙齿,分别使用连续波热牙胶垂直根管充填以及冷侧压根管充填。B组做相同处理。染料渗透法染色后测量根尖微渗漏长度并进行统计学分析。结果：A1组的染色线长度为（1.28±0.39）mm,A2组的染色线长度为（1.36±0.42）mm,B1组的染色线长度为（1.68±0.44）mm,B2组的染色线长度为（1.96±0.41）mm。其中A、B组间在统计学上无显著性差异,即不同的根管预备方法下,根尖的微渗漏无明显不同。A1、B1,A2、B2组间在统计学上有差异（P〈0.05）,说明不同的根管充填方法下,根尖微渗漏不同。结论：在离体实验条件下,连续波热塑充填具有较好的根管壁适应性和密合度,充填效果优于冷牙胶侧压充填方法。而根管预备方法的选择对根尖微渗漏的影响尚未发现明显差异。     

连续波热牙胶垂直充填术根尖微渗漏的研究

目的 评价连续波热牙胶垂直充填术在根充后3、7、30d的根尖微渗漏情况,并与根管冷侧压充填做比较.方法 将87颗单根人离体牙,常规根管预备,随机分为2组,S组43颗牙采用连续波热牙胶垂直根管充填术;L组44颗牙选用冷侧压根管充填术.2组根管充填后进行染色,分别在3、7、30d纵向劈开牙后,测量染色线长度并进行统计学分析.结果 S3d组,L3d组,S7d组,L7d组的染色线长度分别为2.13±2.13mm,3.50±2.05mm,5.36±3.58mm,3.58±2.95mm,统计学无显著性差异(P＞0.05).S30d组和L30d组的染色线长度分别为4.73±3.90mm,7.33±5.05mm,S30d比L30d短,但统计学没有差异(P＞0.05).结论 连续波热牙胶垂直充填术在根尖微渗漏方面,短期内与冷牙胶侧压充填术无明显差异.长期(1个月以上)优于冷牙胶侧压充填术,但统计学无差异.     

桩道预备后剩余根管充填物的根尖封闭作用评价

目的:比较不同根管充填方法及桩道预备后不同长度的充填材料对根尖的封闭作用,寻找根管充填方法和剩余充填材料的最佳搭配选择,为临床应用提供理论依据.方法:132颗单根管牙随机分为6个实验组(每组各20颗)和2个对照组(每组各6颗).根管预备后A、B、C3组行冷牙胶侧方加压充填,桩道预备后分别剩余4、6、8 mm根管充填物;D、E、F3组行连续波热牙胶充填,桩道预备后分别剩余4、6、8 mm根管充填物;G组(阴性对照组)随机选择不同充填方法及不同长度剩余根管充填物:H组不进行根管充填.利用葡萄糖定量检测微渗漏模型,检测各组从冠方向根方渗漏的葡萄糖浓度(体积).采用SPSS 19.0软件包对数据进行统计学分析.结果:A和D、B和E、C和F比较,冷牙胶侧方加压充填组微渗漏显著大于热牙胶充填组.A和B、A和C、D和E、D和F相比,差异均具有显著性;B和C、E和F相比,无显著差异,说明根尖剩余4 mm和6 mm组间具有显著差异,而剩余6 mm和8 mm组间无显著差异.结论:连续波热牙胶充填技术的根尖封闭性能显著优于冷牙胶侧方加压法.桩道预备后剩余6 mm微渗漏较少.是较合适的剩余充填材料长度.     

ObturaⅡ热牙胶系统根管充填的微渗漏研究

目的:比较ObturaⅡ热牙胶系统在3种加热温度设定下充填根管后根尖封闭效果的差异,并与冷牙胶侧压充填技术的密封性进行比较.方法:28个离体单根管恒牙,根管预备后随机均分为4组:A组用传统的泠牙胶侧压充填法进行充填,B、C、D组用ObturaⅡ系统将牙胶分别加热至160℃、180℃、200℃进行充填.使用染料渗入法检测根尖微渗漏的发生情况.结果:ObturaⅡ热牙胶系统在160℃、180℃、200℃的温度设定下充填后的微渗漏与冷牙胶侧压法相比差异有统计学意义(P<0.05),但温度设定不同的热牙胶充填组间的微渗漏差异无统计学意义(P<0.05).结论:ObturaⅡ热牙胶系统加热温度设定在160℃、180℃、200℃进行充填时根尖封闭能力无显著差异,但其根管封闭能力明显优于冷牙胶侧压充填技术.     

Obtura Ⅱ热塑牙胶改良充填法的实验研究

目的探讨将常温流动牙胶充填术融入高温注射式热牙胶充填技术的可行性。方法 70颗单根管离体牙根管预备后随机分组,分别采用ObturaⅡ充填(A组)、Touch-heat+ObturaⅡ充填(B组)、GuttaFlow+ObturaⅡ充填(C组)、冷牙胶侧压充填(D组)、不做充填(E组),根充完成后修整所用充填根管内牙胶长度为10 mm,建立葡萄糖微渗漏模型,通过对葡萄糖定量分析检测根管充填后根尖部微渗漏,观察比较根尖封闭效果。结果各组葡萄糖微渗漏随观察时间延长持续增加,3组实验组微渗漏差异无统计学意义(P>0.05)。结论 GuttaFlow+ObturaⅡ充填法封闭效果可靠且操作易行,有一定的可行性。     

桩腔预备对冷热牙胶充填根管根尖封闭性的影响

目的:通过葡萄糖定量检测法检测根管桩腔预备后微渗漏的大小,比较连续波热牙胶充填和冷牙胶侧压充填后桩腔预备对根尖封闭性的影响。方法:50颗单根管牙,采用冠向下法,使用ProTaper机用镍钛系统预备根管。随机选择5颗牙为阴性对照组,5颗牙为阳性对照组。另40颗牙随机分为A、B、C、D 4组,每组10颗,A组、B组、阴性、阳性对照组使用连续波热牙胶充填术充填根管,阳性对照组不使用根管封闭剂,C组、D组使用冷牙胶侧压充填术充填根管,然后A组:即刻、B组:第7天、C组:即刻、D组:第7天进行桩腔预备。采用葡萄糖定量法测定第2、7、14、21、28天从冠方向根方渗漏的葡萄糖量。结果:第14天起A、B 2组之间,C、D 2组之间,A、C 2组之间,B、D 2组之间,葡萄糖渗漏量差异均有显著性(P<0.05)。结论:延迟桩腔预备会削弱充填材料和封闭剂封闭根管的能力,连续波热牙胶充填的根尖封闭能力优于冷牙胶侧压充填。     

热塑牙胶充填根管临床观察

目的：观察连续波热塑牙胶注射法充填根管的临床效果.方法：选择360例根管治疗患者,共380颗牙,其中240颗牙用热塑牙胶注射充填仪做连续波热塑牙胶充填根管,140颗牙用常规冷牙胶侧方加压充填根管,通过X线片比较两组病例的充填质量并比较两组病例间每根管根充需用时间.结果：X线片显示连续波热塑牙胶充填组欠填率1.67％,超填率2.91％,恰填率95.41％,冷牙胶侧压充填组欠填率8.57％,超填率2.85％,恰填率88.57％,比较两组间欠填率与恰填率有统计学差异（P＜0.05）,连续波热塑牙胶充填组平均每根管根充时间8 min.冷牙胶侧压组充填平均每根管根充时间12 min.连续波热塑牙胶充填组缩短根充时间30％.结论：连续波热塑牙胶充填术比冷牙胶侧方加压充填术根管充填质量更高且节约根充时间,提高了工作效率.     

2种根管充填方法的根尖封闭性比较

目的:比较侧压法与侧压垂直相结合法(混合法)根管充填后的根尖封闭性。方法:选择79颗单直根管离体前牙,经逐步后退法预备根管。75颗牙随机分为2组进行根管充填,A组:40颗,侧压充填;B组:35颗,侧压充填和垂直加压充填联合使用。另4颗作为对照组。1%亚甲基蓝溶液染色72h后,将牙体纵劈,观察根尖部染料的渗漏情况。结果:2组标本充填后,染料的线性微漏长度存在显著差异(P<0.01),混合充填法组的微漏较侧压法小。结论:侧压充填后对根管近冠1/3牙胶进行热垂直加压,可减少微漏的发生。     

采用葡萄糖定量分析法评价连续波热牙胶充填技术的根管封闭性能的研究

目的采用葡萄糖定量法检测根管微渗漏模型评价连续波热牙胶充填技术的根管封闭性。方法选取30颗离体单直根管下颌前磨牙,机用镍钛ProTaper根管预备后随机分成连续波热牙胶充填组和冷牙胶侧方加压充填组(每组10例)和2个对照组(阳性对照和阴性对照各5例),根充后建立微渗漏葡萄糖定量分析法模型,通过在第1、4、7、20天用葡萄糖氧化酶法检测从冠方向根方渗出的葡萄糖的量,观察其微渗漏情况。结果第1天2组微渗漏值无显著性差异(P>0.05),第4、7天,连续波充填组的微渗漏小于冷侧压充填组(P<0.05),第20天时,2组无显著性差异(P>0.05)。结论尽管冷侧压充填发生微渗漏快于连续波充填,但是两者的根管封闭性无显著差异。     

System-B充填技术对模拟侧支根管充填效果的体外评价

目的:研究System-B连续波垂直加压充填技术对不同部位、不同直径侧支根管的充填情况.方法:选取人类单根管离体牙40颗,随机分为2组.根管预备后,在距根尖3mm、6mm、9mm处制备8#及15#K锉直径的人工侧支根管,分别用System-B连续波垂直加压充填技术和传统冷牙胶侧压充填法进行充填.制备成透明牙后,在体视显微镜下观察侧支根管的充填情况,采用SPSS13.0软件包对2组的充填效果进行比较.结果:System-B连续波垂直加压充填技术组和冷牙胶侧方加压充填技术组对侧支根管的充填率分别是85.00%和49.17%(P<0.05).System-B连续波垂直加压充填技术组对距根尖孔6mm、9mm处的侧支根管充填率及进入侧支根管充填物长度均优于3mm处(P<0.05),而6mm与9mm处的侧支充填,无论充填率或是充填长度,两者均无显著性差异(P>0.05);侧支根管充填的充填长度显示,直径较大的15#K锉组优于直径较小的8#K锉组(P<0.05).结论:System-B连续波垂直加压充填技术对侧支根管的充填效果优于冷牙胶侧压充填技术,其对不同部位及不同直径的侧支根管的充填效果也有差别.     

The influence of condensation method on porosity and shade of body porcelain

Condensation of porcelain is an important laboratory variable that can affect a variety of physical properties in metal ceramic restorations. This study examined four methods of condensation (brush with vibration, ultrasonic vibration, spatulation, and noncondensation) to evaluate their effects on porosity and color. Standardized 12 x 12 mm acetate plastic squares were invested and cast with Olympia alloy. After oxidation, the metal substructures received one of the following opaque and body porcelains: Ceramco II G Series, Will-Ceram V-Series, Vita VMK-68, or Jelenko. The examination of each sample consisted of three parts: (1) apparent specific gravity analysis (porosity); (2) tristimulus colorimeter analysis; and (3) subjective observer color analysis. No statistical differences (p less than or equal to 0.05) in apparent specific gravity were found between methods of condensation within any of the four porcelains. Statistical differences (p less than or equal to 0.05) in color were noted between methods of condensation within several of the porcelains by both the tristimulus colorimeter and the subjective observers.     

侧向加压和垂直加压充填技术的根管微渗漏

目的:用葡萄糖定量法检测根管微渗漏的模型,评价侧向加压充填技术和垂直加压充填技术封闭根管的能力。方法:选取 70颗直根管的上前牙,根管预备后随机分为对照组(阳性对照和阴性对照各 5颗)和A、B、C、D4个试验组,A、B组用侧向加压充填技术,C、D组用垂直加压充填技术充填根管,A、C组的封闭剂为AHPlus,B、D组为PulpCanalSealerEWT。于第 1、2、4、7、10、15、20、30天用葡萄糖氧化酶法检测从冠方向根方漏出的葡萄糖的量。结果:第 1、2、4天 4组微渗漏值无显著性差异(P>0. 05), A组和B组第 20、30天,B组和D组第 15、20、30天有显著性差异(P< 0. 05);从第 4天起,垂直加压充填技术的微渗漏小于侧向加压充填技术(P<0. 05)。当用侧向加压技术充填根管时,AHPlus的微渗漏小于PulpCanalSealerEWT,用垂直加压技术充填根管时, 2种封闭剂的微渗漏值无显著性差异。结论:垂直加压充填技术封闭根管的能力优于侧向加压充填技术。     

A description of an alternative method of lateral condensation and a comparison of the ability to obturate canals using mechanical or traditional lateral condensation

A modification of the lateral condensation of gutta-percha technique is described. After master cone adaptation is completed a nickel-titanium finger spreader placed in a reciprocating-action handpiece is used to laterally displace cold gutta-percha, creating space for accessory cones. The technique produces a compacted mass of gutta-percha in the canal, which can usually be removed in toto if corrections are required. This technique was compared with lateral condensation by obturating curved or straight canals in acrylic blocks, then removing, sectioning, and weighing the gutta-percha mass. Two different operators were also compared. Results were analyzed using a factorial ANOVA test. The experimental obturations were significantly heavier on average than were lateral condensation fills (p < 0.001). One operator's obturations were consistently heavier than the others (p < 0.001). There was no significant difference between the weight of fills in straight and curved canals.     

A new method to measure the condensation pressure of amalgam under in vivo conditions

The purpose of this study was to investigate the condensation pressure of amalgam achieved under close to in vivo conditions by 42 general practitioners who were asked to fill a pre-cut standard class 2 cavity in a mannequin head. A measuring device was designed to allow the maximum and average condensation pressures and working and resting periods to be obtained. The results showed a maximum condensation pressure of 9.17 +/- 3.04 MPa and 4.09 +/- 1.41 MPa with a small (diameter, 1.15 mm) and a large (diameter, 1.8 mm) amalgam plugger, respectively. Only one of the 42 dentists reached the recommended condensation pressure of 15 MPa (J?rgensen, 1977). A significant (p less than or equal to 0.001) correlation between the duration of the working periods and the maximum condensation pressure was found (r = 0.61). Further investigations are required to determine the influence of these different condensation pressures on the physical properties of various amalgams.     

A comparison of fill density obtained by supplementing cold lateral condensation with ultrasonic condensation

The purpose of this study was to compare quantitatively the density of gutta-percha root canal fillings produced by cold lateral condensation with those produced by an ultrasonically energized spreader in a warm lateral condensation technique in artificial root canals. Thirty-degree simulated root canals in 30 transparent acrylic blocks were instrumented by using rotary files. The blocks were weighed. The canals were obturated with gutta-percha using cold lateral condensation without sealer and then weighed again. Two applications of warm lateral condensation were then performed on the same 30 canals using the UES. The blocks were weighed once more after each additional UES obturation treatment. The first heat application produced a 26.92% increase in weight over lateral condensation, and the second heat application produced an additional 5.95% increase. A one-way repeated measures ANOVA followed by the Tukey-Kramer test revealed that both applications of warm lateral condensation produced significant (p < 0.001) increases in weight. Results indicate that warm lateral condensation using a ultrasonically energized spreader results in denser gutta-percha fills by weight than cold lateral condensation.