桩道预备对不同根管糊剂充填后根尖封闭性的影响

目的 液体转移法评价根管桩道预备对三种根管糊剂充填后根尖封闭性的影响。方法24颗人上颌前牙截冠后统一工作长度为16 mm,进行根管预备及根管充填。样本随机分组为Endométhasone组、AH-P lus组和GuttaF low组,每组8个样本。1周后液体转移法测量桩道预备前根管微渗漏。随后1~6#G钻逐步桩道预备,保留根尖4 mm充填物。再测量桩道预备后的根管微渗漏。实验数值采用SPSS 13.0统计学软件进行霍特林T2检验,取α=0.05。结果 桩道预备对各实验组的影响无统计学意义(P>0.05)。GuttaF low组桩道预备后的微渗漏值最小为(4.393±2.052)×10-3μl/(kPa.m in)。结论 桩道预备不影响根管糊剂充填后的根尖封闭性。GuttaF low是值得推广的新型根管充填剂。     

液体转移法评价3 种根管充填剂的封闭性能

采用液体转移法评价3 种根管充填剂(Endométhasone、AH-Plus、GuttaFlow)的根管微渗漏,通过扫描电镜观察根管壁与充填剂之间的结合特征.结果表明GuttaFlow组的微渗漏值最小,Endométhasone组的微渗漏值最大.3 种材料间比较均有统计学差异(P<0.05).扫描电镜下不同根管充填剂与根管壁的结合情况不同.GuttaFlow的根管封闭性能较其他2 组更佳.     

车针转速对GuttaFlow根管充填后微渗漏的影响

目的 研究桩道预备过程中不同车针转速对GuttaFlow根管充填后微渗漏的影响。方法 40颗人上颌前牙截冠后统一工作长度为16mm,根管预备后GuttaFlow充填根管。样本按桩道预备车针转速随机分为5组:A组(车针转速为400r/min)、B组(800r/min)、C组(7000r/min)、D组(14000r/min)、E组(对照组,不进行桩道预备)。1周后各组按设定转速进行桩道预备,保留根尖4mm充填物。液体转移法测量根管微渗漏。实验数值采用SPSS13.0统计学软件进行单因素方差分析。结果 A组微渗漏值最大(7.531±1.309)×10-3μl/(kPa·min),与E组间有统计学差别。A组和D组间有统计学差异。其余各组间无统计学差异。结论 桩道预备过程中车针转速对GuttaFlow根管充填后微渗漏产生影响,转速过低时(400r/min)增加充填根管的微渗漏,不推荐使用于临床。?     

桩道预备对两种新型根管充填剂封闭性的影响

目的液体转移法评价根管桩道预备对两种新型根管糊剂充填后根尖封闭性的影响。方法 24颗人上颌前牙截冠后统一工作长度为16mm,进行根管预备。样本随机分组为Endofill组、Acroseal组和AH Plus组(对照组),每组8个样本。根管充填1周后液体转移法测量桩道预备前根管微渗漏。随后1-6号G钻逐步桩道预备,保留根尖4mm充填物。再次测量桩道预备后的根管微渗漏。实验数值采用SPSS 13.0统计学软件进行霍特林T2检验,取α=0.05。结果桩道预备增加Endofill组的根尖微渗漏,差别有统计学意义(P<0.05)。桩道预备不影响Acroseal组和AH Plus组的根尖微渗漏(P>0.05)。结论桩道预备降低了Endofill的根尖封闭性。建议Endofill慎用于需桩核冠修复的根管充填。     

不同根管封闭剂的体外微渗漏研究

目的 比较临床常用的5种根管封闭剂的微渗漏量,以期为临床医师选择应用提供参考.方法 制作并检测液压微渗漏装置,将100颗单根双尖牙根管预备后分为5组,每组20颗,分别采用ZOE(A组)、Sealapex(B组)、AH Plus(C组)、Sealite(D组)、Cortisomol(E组)5种根管封闭剂,均使用冷侧压方法进行根管充填,于48 h及3个月后分别用微渗漏测量装置测量微渗漏量,采用单因素方差分析对各组结果进行比较(α=0.05).结果 根充后48 h和3个月不同封闭剂组间微渗漏量差异均有统计学意义(P＜0.01),根充后48hB组微渗漏量[(5.8±1.1)μl/3 h]显著大于其他4组(P＜0.01),根充后3个月B组的微渗漏量减少至(2.5±0.5) μl/3h,与根充后48 h相比差异有统计学意义(P＜0.01).C组根充后48 h[(0.8±0.2) μl/3 h]和3个月微渗漏量[(1.4±0.6)μl/3 h)]均最小,根充后48 h与A、B组相比差异均有统计学意义(P＜0.05),3个月时与A组相比差异有统计学意义(P＜0.05).结论 AH Plus封闭剂在体外实验中体积稳定、微渗漏少、封闭性能良好,临床选择封闭剂时可以参考.     

不同根充材料对于根尖封闭性能的纵剖面研究

目的:评价3种根管充填糊剂的根管封闭能力,分析其影响因素。方法:收集新鲜拔除的完整单根管下颌第一前磨牙60颗,随即分为A、B、C三组,每组20颗牙,分别用氧化锌丁香油糊剂、Vltapex糊剂、AH-Plus糊剂加牙胶尖以侧压法进行根管充填,采用染料渗入法测染料渗入距离,并通过扫描电镜观察根尖1/3、根中1/3、根颈1/3中根管壁与糊剂之间的结合状态。结果:扫描电镜下3类糊剂在根颈1/3与根管壁的粘结最紧密,在根尖1/3与根管壁的粘结最疏松。其中AH-Plus组可见材料呈均质状分布,与管壁粘结最为紧密。在根尖1/3处AH-Plus组(2.11±0.22)μm的微缝隙宽度明显低于氧化锌丁香油糊剂(8.63±0.25)μm和Vitapex糊剂(7.58±5.62)μm(P<0.05)。3种根管充填材料的染料渗透距离中,AH-Plus组的微渗漏值(0.98±0.58)mm明显小于氧化锌丁香油糊剂(2.32±0.55)mm和Vitapex糊剂(2.11±0.67)mm(P<0.05)。结论:AH-Plus糊剂对于根管充填特别是根尖有很好的密合性,能有效防止根尖微渗漏现象的发生。     

液体转移法评价桩道预备对根管充填后封闭性的影响

目的：液体转移法评价桩道预备对4种根管充填材料根管充填后微渗漏的影响。方法：32颗人上颌前牙截冠后统一工作长度为16ram,样本随机分组为Endoln~thasone组、AH—Plus组、Vitapex组和国产组,每组8个样本。根据充填材料不同进行根管预备及根管充填。一周后液体转移法测量桩道预备前根管微渗漏。桩道预备后,再测量根管微渗漏。实验数值采用SPss13．0统计学软件进行分析,取α=0．05。结果：Endom6thasone组、AH-Plus组的桩道预备前和桩道预备后无统计学差别。Vitapex组、国产组的桩道预备后微渗漏下降,与桩道预备前有统计学差别（P〈0．05）。结论：桩道预备不影响Endom6thasone、AH—Plus根管充填后的微渗漏;桩道预备使Vitapex、国产充填剂根管充填后的微渗漏下降。     

桩道预备对3种方法充填根管封闭性能的影响

目的：了解根管桩道预备对3种充填方法根充后根管封闭性的影响。方法：采集因牙周病拔除的人上颌前牙24颗,截冠后统一工作长度为16mm,分为A、B、C3组。A组用常温流动牙胶单核充填技术,GuttaFlow系统;B组用传统侧压充填技术,AH Plus糊剂;C组用垂直加压充填技术,AH Plus＋BeeFill热牙胶充填系统。按各组系统充填要求,进行根管预备和根管充填。1周后,采用液体传输法,测量各样本桩道预备前根管微渗漏。随后用1-6号G钻逐步桩道预备,保留根尖4mm充填物。再测量桩道预备后的根管微渗漏。实验数值采用SPSS13.0软件包进行分析。结果：桩道预备对各实验组的影响无统计学意义（P〉0.05）。桩道预备前,A组和B组之间,B组和C组间有统计学差异（P〈0.05）。桩道预备后,A组和B组之间有统计学差异。A组桩道预备后的微渗漏值最小,为（4.328&#177;2.020）&#215;10^-3μl&#183;kPa^-1&#183;min^-1。结论：桩道预备不影响3种充填方法根充后的根尖封闭性。AH Plus应用不同的充填技术进行充填,根管微渗漏表现不同。GuttaFlow所代表的常温流动牙胶单核充填技术的根管封闭性最佳。     

不同时机核预备对纤维桩核系统微渗漏的影响

目的 观察粘接纤维桩核后不同间隔时间核预备对桩核系统微渗漏的影响,以期为临床桩核预备时机提供实验依据.方法 对45颗人下颌前磨牙进行截冠、根管预备和热牙胶充填,并分别于纤维桩核粘接后5、15和30 min行核预备(桩核组,每组10颗样本牙),阳性对照组(每组5颗样本牙)仅充填根尖5 mm热牙胶,阴性对照组(每组10颗样本牙)桩核修复后不进行核预备.采用液体输送法检测桩核系统微渗漏量,并于扫描电镜下观察并测量粘接界面缝隙.结果 高速机头行核预备后桩核系统微渗漏量增加,阴性对照组微渗漏量[(1.50×10-6 ±0.37×10-6) μl· min-1·Pa-1]均显著低于3个桩核组(P＜0.05);5 min桩核组微渗漏量为(6.02 ×10-5 ±1.02 ×10-5)μ1·min-1·pa-1,明显高于15 min桩核组[(1.50×10-5 ±0.26×10-5) μl· min-1·Pa-1 ]和30 min桩核组[ (1.50 ×10-5±0.39×10-5)μl· min-1·Pa-1] (P＜0.05).扫描电镜观察5 min桩核组根管壁与粘接剂间缝隙较大,且由根尖向根颈逐渐扩大.结论 高速机头振动对纤维桩核系统封闭性有负面影响,本项实验条件下粘接纤维桩核后应过15 min再行核预备,微渗漏量显著降低.     

3种根充糊剂用于妊娠妇女急性根尖周炎治疗的临床观察

目的观察3种根充糊剂用于孕妇根尖周炎的效果。方法选择孕妇急性根尖周炎患牙102个,随机分3组,分别用3种根充糊剂进行根管消毒和根管充填,即氢氧化钙碘仿糊剂(A组)、氢氧化钙糊剂组(B组)和碘仿糊剂组(C组)。定期复查。结果A组有效率为92.7%,B组有效率为87.5%,C组有效率为84.4%,3组差异均无显著性(P>0.05)。结论氢氧化钙碘仿糊剂可用于孕妇急性根尖周炎的根管消毒和根管充填。     

Sharpening of ultrasonic sealers

Instruments suitable for removing calculus, plaque and necrotic cementum, which hinder normal periodontal reattachment, are extremely important for successful therapy. The test was carried out in order to see if a standard scaler used for ultrasonic tartar removal maintains its physical features when sharpened. 6 scalers, compatible with piezo-electric generators, were tested and 2 diameters, A and B, weights and resonance frequencies were measured. Scalers no. 2, 3, 4, 5, were sharpened and was used as control. All measurements were taken again at the end of the test. Statistical analysis reveals significant variations, after sharpening, of A diameter (t = 4.14 greater than 3.55, p less than 0.01), B diameter (t = 5.34 greater than 3.355, p less than 0.01) and resonance frequency (t = 2.82 greater than 2.306, p less than 0.05); in contrast, there is no significant change of weights (t = 1.17 less than 2.306, p greater than 0.05). These results suggest that sharpening slightly modifies the physical features of ultrasonic tips, so that sharpening ultrasonic scalers, from a physical point of view, can be carried out, paying attention not to damage the water cooling system.     

A study of the rheological properties of endodontic sealers

AIM: To test the hypothesis that there would be no statistically significant difference in viscosity-related measures of endodontic sealers or change in these with strain rate, internal diameter or powder : liquid ratio in a capillary system. METHODOLOGY: Materials used were Apexit, Tubliseal EWT, Grossman's sealer and Ketac-endo. Viscosity-related measures were tested in a two-plate test, and in a capillary rheometer. The mean values (n = 12) for thickness and diameter of material formed between two glass plates were tested with one-way analysis of variance. Pressure was applied to a capillary rheometer at strain rates 5 and 10 mm min(-1) in tubes of internal diameter 0.6 and 1.2 mm. RESULTS: Tubliseal EWT had a thinner film thickness than the other sealers (alpha = 0.05). The difference in diameter between Tubliseal EWT and the other sealers was significant apart from Apexit. Increased strain rate gave a significant increase (alpha = 0.05) in the flow of all sealers. Narrower tubes produced increased velocity, which was significant for all sealers, and reduced volumetric flow, which was significant for all sealers except Grossman's 2 : 1 (Wilcoxon signed rank test). Reduction in powder : liquid ratio of Grossman's significantly increased flow in narrow tubes and at higher strain rate (Mann-Whitney test). CONCLUSION: There was a significant difference between the flow of Tubliseal EWT and the other sealers tested in the two-plate test; capillary flow was affected by sealer, internal diameter, strain rate and powder : liquid ratio. The null hypotheses were rejected.     

Apical leakage of four endodontic sealers

The purpose of this study was to evaluate the sealing properties of four root canal sealers. Forty-eight maxillary central incisors were instrumented with Profile rotary instruments. They were randomly divided into four groups (n = 12) and filled using lateral condensation with one of the four sealers: Sealapex, Pulp Canal Sealer, AH 26, and Ketac-Endo. The apical leakage was measured with a fluid filtration method and expressed as L s(-1) KPa(-1). The teeth filled with Sealapex displayed a higher apical leakage (8.42 +/- 4.2 10(-11) L s(-1) KPa(-1)) than those filled with AH 26 (2.10 +/- 1.39 10(-11) L s(-1) KPa(-1)), Pulp Canal Sealer (0.17 +/- 0.09 10(-11) L s(-1) KPa(-1)) or Ketac-Endo (0.32 +/- 0.24 10(-1) L s(-1) KPa(-1)) (p < 0.01). No statistically significant difference was found among AH 26, Pulp Canal Sealer, and Ketac-Endo. No correlation was found between the sealing efficiency of the four sealers and their adhesive properties recorded in a previous study.     

Clinical performance of three endodontic sealers

Abstract The clinical performance of three endodontic sealers, AH 26®, Kloroperka N-Ø® and ProcoSol®, was assessed in a prospective study of endodontic treatment in 810 roots. The roots were treated by undergraduate students according to a standardized procedure, and were filled with laterally condensed gutta-percha and sealer. The sealer was randomly selected just prior to filling. The patients were recalled yearly for 4 years for a clinical and radiographic control examination, and the radiographs were scored using the periapical index (PAI) scoring system. Ridit analysis provided optimal discrimination between subgroups of roots with regard to the radiographic status of the periapical tissues as a measure of the clinical performance of the materials. The periapical status of roots filled with AH 26® or ProcoSol® was better than that of roots filled with Kloroperka®. The difference was significant after 1 year and persisted through the 4-year observation period. The difference was also evident after stratification of the material with regard to preoperative pulpal and periapical diagnoses. It is concluded that the choice of sealer may influence the outcome of endodontic treatment, and that the perapical index is a useful discriminatory tool for assessment of treatment results in endodontics.