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±2.020）×10^-3μl·kPa^-1·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。     

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。     

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。?     

即刻与延迟桩腔预备对3种根充糊剂加牙胶根充后根尖封闭性影响的研究

目的 评价即刻桩腔预备与延迟桩腔预备对3种根充糊剂充填根管根尖封闭性的影响。方法 选取离体直根管牙105颗,截冠后随机分为5组。A组:牙胶尖+AH Plus根充(n=30);B组:GuttaFlow+单牙胶尖根充(n=30);C组:牙胶尖+ZOE根充(n=30)。D组:为阳性对照,牙胶尖根充(n=10);E组:为阴性对照,牙胶尖根充(n=5)。其中A、B、C各组内分别随机分为A1、A2、A3,B1、B2、B3,C1、C2、C3组(n=10)。各组均采用手用Protaper冠向下法预备根管。对A1、B1、C1组行即刻桩腔预备;A2、B2、C2组根充1周后行延迟桩腔预备。A3、B3、C3、D、E组不做桩腔预备。利用印度墨水染色,透明牙技术评价经即刻桩腔预备与延迟桩腔预备后剩余根充材料的根尖微渗漏情况。结果 即刻与延迟桩腔预备在相同根充材料之间对根尖的封闭性影响无统计学差异(P>0.05);相同预备时机不同材料组间比较AH Plus组和GuttaFlow组好于ZOE组(P<0.05),AH Plus组和GuttaFlow组间无统计学差异(P>0.05)。结论 即刻与延迟桩腔预备对相同根充材料根尖封闭性的影响无统计学差异。建议根充后行即刻桩腔预备并使用AH Plus或GuttaFlow做根充糊剂。     

纤维桩桩道预备时机对根尖微渗漏影响的体外对比研究

目的：对比纤维桩桩道不同预备时机对根尖微渗漏的影响。方法收集30颗离体下颌单根管前磨牙,采用ProTaper冠向下法预备根管,热牙胶垂直加压充填技术充填根管后,将样本随机平分成3组, A组为即刻桩道预备组,B组为2d后桩道预备组,C组为7d后桩道预备组。染料渗入法及透明牙技术处理后,在显微镜下记录各组根尖微渗漏长度,并进行t检验统计学分析。结果 A组根尖微渗漏长度为（0.96±0.15）mm ,B组根尖微渗漏长度为（0.97±0.11）mm ,C组根尖微渗漏长度为（1.01±0.12）mm ,3组样本根尖微渗漏值均较小,且3组结果之间差异均无统计学意义（P＞0.05）。结论纤维桩桩道预备时机对根尖微渗漏无明显影响。     

MTAD作为根管冲洗剂的效果评价

目的探讨应用MTAD作为根管冲洗剂去除根管壁玷污层的效果,以及对根管充填后根尖微渗漏的影响。方法采集因正畸或牙周病拔除的前磨牙,截冠后统一工作长度16 mm,按照冲洗液使用的不同,随机分为A、B、C 3组,每组12颗。A:生理盐水;B:MTAD;C:5.25%NaClO+15%EDTA。采用机用Protaper镍钛根管锉进行根管机械预备,分别用相应冲洗液冲洗,根管预备后每组4颗牙齿用于制备扫描电镜标本,观察根管表面玷污层和牙本质小管暴露的情况。每组剩余8颗进行根管充填,1周后,采用液体转移法,测量各样本根管微渗漏。实验数值采用SPSS 19.0软件包进行分析。结果 A组沉积大量玷污层,牙本质小管被遮蔽,B、C组玷污层得到有效的清除,牙本质小管开放。根管充填后,A组和B组之间,A组和C组间的微渗漏值有统计学差异(P<0.05),B组合C组之间无统计学差异(P>0.05),其中A组的微渗漏值最大。结论 MTAD冲洗剂可以替代5.25%NaClO+15%EDTA联用,能有效地去除根管充填过程中产生的玷污层,增强根管充填后的根尖封闭性。     

iRoot SP单尖充填后即刻与延迟桩道预备对根尖封闭性能的研究

目的:评价iRoot SP单尖充填根管后即刻与延迟桩道预备的根尖封闭效果。方法:收集因正畸拔除的70颗单根管前磨牙,截冠后随机分为8组。A1、B1、C1组:AH Plus+热牙胶充填(n=10);A2、B2、C2组:iRoot SP+单尖充填(n=10);D、E组分别为阳性、阴性对照组。A1、A2组行即刻桩道预备,B1、B2组行延迟桩道预备,C1、C2组根管充填后不进行桩道预备。使用印度墨水染色技术,透明牙技术评价不同时机桩道预备后根尖微渗漏情况。结果:各实验组均有染料渗入,相同充填方法下,不同桩道预备时机的各组间(A1-B1,A2-B2)差异无显著性(P>0.05);而相同桩道预备时机,不同充填方法的各组间(A1-A2,B1-B2)也无显著性差异(P>0.05)。无桩道预备组与即刻桩道预备组(C1-A1,C2-A2)之间的比较,差异无统计学意义(P>0.05),但与延迟桩道预备组(C1-B1,C2-B2)组间比较有差异(P<0.05)。结论:iRoot SP单尖充填和AH Plus热牙胶充填具有相似的根尖封闭效果;iRoot SP单尖充填后即刻桩道预备与延迟桩...     

3种根充糊剂根尖封闭性能的实验研究

目的评价3种根充糊剂的根尖封闭能力。方法30颗离体单根管前牙随机分为国产根充糊剂、Vitapex糊剂和AHPlus糊剂3组,每组10颗,分别用加牙胶尖以冷侧压法充填根管,用染料渗透法和透明标本法在立体显微镜下测量根尖微渗漏。结果3组根尖微渗漏的均值分别为:国产根充糊剂组(2.555±1.129)mm,Vitapex糊剂组(1.212±0.625)mm,AH Plus糊剂组(0.919±0.427)mm,3组间差异有显著性(P<0.01),Vitapex组和AH Plus组的微渗漏无明显差异(P>0.05)。结论Vi-tapex糊剂和AH Plus糊剂的根尖封闭性能均优于国产根充糊剂。     

玻璃离子减少桩道预备后根管微渗漏的实验研究

目的 研究桩道预备后用玻璃离子封闭根充物冠方对减少根管微渗漏的效果.方法 选取70颗离体单根管下颌前磨牙,阳性对照组5颗,阴性对照组5颗,A、B、C、D 4组各15颗.常规根管充填后,A、B、C、D 4组进行桩道预备,A组保留根尖4 mm根充物;B组保留根尖5 mm根充物;C组保留根尖3 mm根充物 1 mm Vitrebond玻璃离子;D组保留根尖4 mm根充物 1 mm Vitrebond玻璃离子.用葡萄糖微渗漏模型检测6组第1、2、 4、 7、 10、 15、 20、 25、 30天根管冠根向渗漏出的葡萄糖量.结果 A、B、C、D 4组第 1、 2、 4、 7 天微渗漏值差异无统计学意义(P>0.05);从第10天开始, A、B组微渗漏值均明显高于C、D组(P<0.05),而C、D组之间差异无统计学意义(P>0.05);A、B组微渗漏值在第20、 25、30天差异有统计学意义(P<0.05).结论 玻璃离子可以成功减少桩道预备后根管的微渗漏.     

Apical sealing of root canal fillings performed with five different endodontic sealers: analysis by fluid filtration

Objectives

To evaluate the sealing ability of five root canal sealers, including two experimental cements (MBP and MTA-Obtura) using the fluid filtration method.

Material and Methods

Teeth were divided into 5 study groups: G1-AH Plus; G2-Acroseal; G3-Sealapex; G4-MBP; G5-MTA-Obtura; and two controls. Chemical-mechanical preparation was performed with ProFile rotary nickel-titanium instruments 1 mm short of the apical foramen. The sealing ability was evaluated by fluid filtration at 15, 30, and 60 days.

Results

The statistical analysis showed significant difference between the materials at different periods (p<0.05). AH Plus and MBP had similar leakage values at 15 and 60 days, alternating with significant reduction at 30 days, while the other materials showed progressive increase in leakage values. Acroseal and Sealapex presented the best results at 15 days and the worst at 60 days.

Conclusions

All sealers evaluated presented fluid leakage, with AH Plus and MBP showing the best results at the end of the experimental period. Acroseal, Sealapex, and MTA-Obtura presented increase in leakage values at longer observation periods.     

生物根管封闭剂iRoot SP在根管根尖封闭中的应用评价

目的:分析生物根管封闭剂iRoot SP在扁形根管根尖封闭中的性能,为临床工作提供指导.方法:取48颗根管的近远中径与颊舌径之比小于0.5的单根管离体前磨牙,根管预备后,随机分为A、B、C3组,每组各16颗.分别选用Vitapex (A组)、AH Plus(B组)、iRoot SP(C组)作为根管封闭剂,结合连续波热牙胶垂直充填技术进行根管充填.所有样本经根尖染料渗透实验,采用透明牙技术,比较3组离体牙微渗漏情况,评价iRoot SP在扁形根管根尖封闭中的性能.采用SPSS19.0软件包对数据进行统计学分析.结果:A组染料渗入深度显著大于B、C组,差异具有显著性(P＜0.05);B、C组染料渗入深度相比,无显著差异(P＞0.05).结论:iRoot SP和AH Plus在扁形形根管根尖封闭中的性能接近,效果优于Vitapex根管充填糊剂.     

An endodontic sealer induces a pathological condition when associated with persistent tissue toxicity and presence of myofibroblasts

The aims of this study were to evaluate the ratio between inflammatory reactions induced by four endodontic sealers and the occurrence of fibrosis and the number of myofibroblasts with positivity to α-smooth-actin muscle (α-SMA). Polyethylene tubes were filled with a root canal sealer (Endofill, AH Plus, Acroseal and Epiphany) and inserted into 4 site at the dorsal region of 24 Wistar rats; 2 empty tubes (control) were grafted in 6 rats. After 7, 21, and 45 days, 8 animals were euthanized, providing 6 specimens per test group and 2 specimens from the control group. The fragments were subjected to histological processing and immunohistochemical analysis for anti α-SMA protein. All specimens, except those from the control group, presented severe inflammatory reaction on the 7th postoperative day, which also coincided with a large number of myofibroblasts. On the 21st and 45th days post-surgery, the inflammatory reaction induced by Endofill, AH Plus and Acroseal decreased significantly, which coincided with reduced presence of myofibroblasts and usual collagen deposition. In contrast, in the group filled with Epiphany, significant inflammatory cell infiltrate was present in all analyzed periods. The persistence of an inflammatory reaction induced by endodontic sealer may also induce the development of fibrosis in combination with presence of myofibroblasts.     

An in vitro evaluation of the apical sealing ability of a new resin-based root canal obturation system

The purpose of this study was to assess the apical sealing ability of the new resin-based Epiphany-Resilon root canal filling system, and to compare this with the sealing abilities of different pairings of AH plus, gutta-percha, Epiphany, and Resilon. Seventy extracted human single-rooted teeth were used. All teeth were instrumented using a set of ProTaper rotary instruments. The canal spaces were filled with different combinations of core and sealer using lateral condensation, as follows: group 1, AH Plus + gutta-percha; group 2, AH Plus + Resilon; group 3, Epiphany + Resilon; group 4, Epiphany + gutta-percha. Apical leakage quantity was measured with the computerized fluid filtration meter. Statistical analysis indicated that Epiphany gutta-percha combination had the least amount of microleakage than all the other groups; AH Plus gutta-percha combination proved to have second least amount of microleakage among the groups. AH Plus-Resilon combination demonstrated the greatest amount of microleakage. There were a significant difference between Epiphany gutta-percha and AH Plus-Resilon combinations (p < 0.05). It was found that there were no significant differences between Epiphany-Resilon combination and all the other groups (p > 0.05).     

IN VIVO EVALUATION OF THE SEALING ABILITY OF TWO ENDODONTIC SEALERS IN ROOT CANALS EXPOSED TO THE ORAL ENVIRONMENT FOR 45 AND 90 DAYS

This in vivo study evaluated the sealing ability of a resin-based sealer (AH Plus) and a zinc oxide-eugenol sealer (Endofill) in dogs'' teeth, exposed to the oral environment for 45 and 90 days. Forty eight lower incisors from 8 dogs were endodonticaly treated. A stratified randomization determined the sealer use in each root canal. All canals were filled using the lateral condensation technique. The excess filling material at the cervical portion of the root canal was sectioned, leaving a 10-mm obturation length inside the canal. Teeth were provisionally sealed with glass ionomer cement for 24 h and the canals were exposed to the oral environment for either 45 or 90 days. Therefore, the experimental groups were as follows: A45- AH Plus for 45 days; A90- AH Plus for 90 days; E45- Endofill for 45 days; and E90- Endofill for 90 days (n=12). After the experimental period, the dogs were killed and the lower jaw was removed. The incisors were extracted and the roots were covered with two coats of nail varnish. The teeth were immersed in India ink for 96 h and submitted to diaphanization. Dye leakage (in mm) was measured using stereomicroscopy (10x magnification). The results were statistically analyzed using two-way ANOVA and Tukey test for multiple comparisons (á = 0.05). Group E90 (2.03±0.94) showed significantly higher mean leakage value than all other groups (p<0.001). None of the sealers, in both study conditions, were able to prevent dye leakage.     

Comparative in vivo analysis of the sealing ability of three endodontic sealers in dog teeth after post-space preparation

This study compared the sealing ability of RoekoSeal, AH Plus and EndoRez in dog premolars after post-space preparation and exposure to the oral environment. Seventy-four root canals were cleaned, shaped and filled with gutta-percha and one of the sealers. Post spaces were prepared with about 4-mm root canal filling remaining in the apex. Teeth were sealed for 24 h for sealer setting. Teeth were exposed to the oral environment for 45 days. The dogs were killed and root canals were soaked in India ink and sealed for 96 h. The teeth were cleared, and leakage was measured under stereoscopy. The Kruskal-Wallis test was used for analysis. A significant difference was found between EndoRez and RoekoSeal groups (P < 0.05). EndoRez had lower leakage values than RoekoSeal after 45-day exposure to the oral environment. No statistic difference was found in the comparison of AH Plus with the other sealers under study.     

Evaluation of the radiopacity of root canal sealers by digitization of radiographic images

The aim of this study was to evaluate the radiopacity of a zinc oxide and eugenol-based (Endofill), a calcium hydroxide-based (Sealapex), two resin-based (Sealer 26 and AH Plus), and a silicone-based root canal sealer (Roeko Seal). Specimens, measuring 10mm in diameter and 1mm in thickness, were radiographed simultaneously with an aluminum step wedge using occlusal films, according to ISO 6876/2001 standards. Radiographs were digitized, and the radiopacity of sealers was compared to the different thicknesses of the aluminum step wedge, using the VIXWIN 2000 software. Results demonstrated that AH Plus was the most radiopaque sealer, while Sealapex was the least radiopaque (p<0.05). Roeko Seal, Endofill and Sealer 26 presented intermediate radiopacity values. Sealapex presented less radiopacity than the other types of root canal sealers.     

Apical leakage in root canal fillings performed with two types of cement following application of Nd: YAG laser or EDTA solution in the root canal walls

Marginal apical leakage was evaluated in root canal filling performed with two sorts of cements after applying Nd:YAG laser or an EDTA solution in the root canal walls. Sixty-two human lower premolars had their canals instrumented through mechanical technique. Afterwards the external root surfaces were impermeabilized, except for the foramen. The roots were then divided into 4 groups of 15, according to the type of treatment performed on the root canal walls and the type of cement utilized in the filling. Group I - application of Nd:YAG laser and filling with AH Plus cement; Group II - application of Nd:YAG laser and filling with Endofill cement; Group III - application of EDTA for 5 minutes and filling with AH Plus cement; Group IV - application of EDTA for 5 minutes and filling with Endofill cement. Two teeth served as negative and positive controls. Afterwards, the roots were immersed in a 2%-methylene blue dye, for 48 hours. Wearing of the roots took place following the removal of impermeabilization for the reading of leakage magnitude, by means of a light microscope through planimetry technique The results indicated AH Plus cement as the one to allow the least apical leakage, as well as Nd:YAG laser application, when utilized in the treatment of root canal walls, prior to filling.