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。     

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。     

Carisolv处理根管后对冠方微渗漏影响的实验研究

目的:探讨Carisolv应用于根管化学机械预备后对根管冠方微渗漏的影响。方法:将48例符合纳入标准的离体牙随机分为3组,在根管预备过程中分别采用20 g/L氯亚明、Carisolv、EDTA处理根管,并均采用冷牙胶侧方加压技术进行根管充填。扫描电镜观察各组根管充填剂与根管壁之间的黏结效果;染色法检测根管冠方微渗漏的长度。采用SPSS 16.0软件包对结果进行单因素方差分析。结果:扫描电镜观察发现氯亚明和Carisolv组根管充填剂与根管壁间均存在微缝隙,最大宽度分别为64μm和10μm,EDTA处理组充填剂与根管壁贴合紧密。微渗漏测量显示,EDTA组染料渗入长度最低,与其他两组相比差异均有统计学意义(P<0.05);其次为Carisolv组,但与氯亚明组相比无明显差异(P>0.05)。结论:Carisolv作为根管预备化学制剂,对根管冠方微渗漏有一定影响。     

氢氧化钙类根管糊剂的微渗漏研究及扫描电镜观察

目的 液体转移法评价氢氧化钙类根管糊剂的根管微渗漏,扫描电镜观察糊剂在根管内的微观特征.方法 22颗人上颌前牙随机分为2组:A组(Vitapex)和B组(国产根管充填剂),逐部后退法根管预备后根管侧压充填.每组8个样本装入液体转移法装置进行微渗漏实验,3个样本用于扫描电镜观察.结果 A组微渗漏值为(9.878±1.688)×10-4μl/cmH2O/min-1;B组微渗漏值为(11.253±3.205)×10-4μl/cmH2O/min-1.两组间无统计学差异.A组牙本质和根充物间存在间隙;B组根充物颗粒之间存在缝隙.结论 两种氢氧化钙类根管糊剂的根管微渗漏无明显差异.     

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。     

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。?     

三种根管封闭剂根管封闭性能的实验研究

目的：比较三种根管封闭剂的根管封闭能力。方法：选择103颗单根离体牙,根管预备后随机分为3组,分别用AH-plus根管封闭剂＋牙胶（A组）、Cortisomol根管封闭剂＋牙胶（B组）、EndoREZ双固化UDMA树脂根管封闭剂＋牙胶（C组）侧方加压法充填根管,扫描电镜观察封闭剂与根管结合情况,并进行染色法微渗漏实验,观察3、7、30d染色线长度。结果：扫描电镜下观察,树脂类封闭剂与根管壁结合紧密,染色法发现Cortisomol组染色3、7、30d较其它两组微渗漏值高,3、7d无显著性差异（P〉0．05）,30d时有显著性差异（P〈0．05）。结论：树脂类根管封闭剂根管封闭性能较好。     

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。     

单尖法和热牙胶法根管充填根尖封闭性能的比较研究

目的 比较3种封闭剂AH-Plus, iRoot SP和GuttaFlow2分别配合单尖法充填和热牙胶充填的根尖封闭性能。方法 选取近期拔除的70颗单根管前磨牙,截冠后采用Waveone gold系统预备至P#,随机分为6个实验组(每组10颗)和2个对照组(每组5颗)。分别行单尖法充填和热牙胶充填,即AH-Plus单尖法组(A1组),AH-Plus热牙胶组(A2组),iRoot SP单尖法组(B1组),iRoot SP热牙胶组(B2组),GuttaFlow2单尖法组(C1组),GuttaFlow2热牙胶组(C2组),阳性对照组(D组)和阴性对照组(E组)。将充填完成的牙齿进行染料渗透实验后,通过纵切片法检测根尖的微渗漏情况。结果 A1组微渗漏值最大,B2组微渗漏值最小,同种封闭剂下单尖法充填和热牙胶充填根尖封闭性差异无统计学意义(P>0.05),同种充填技术下3种封闭剂的封闭性差异无统计学意义(P>0.05)。结论 3种根管封闭剂均不能完全封闭根管,单尖法充填和热牙胶充填在根尖封闭效果上无显著差异。     

根管充填糊剂根尖封闭性的体外研究

目的：体外评价3种根管充填糊剂的根尖封闭效果。方法选取人离体下颌前磨牙68颗,截冠后随机分为A、B、C、D、E、F 6个组,其中A、B、C、D为实验组（每组12颗牙齿）,E和F分别为阳性和阴性对照组（每组各10颗牙齿）,所有样本均使用K3镍钛器械采用冠向下法完成根管预备后按如下方法进行根管充填：A、B组分别用树脂类根管充填糊剂AH Plus和生物陶瓷类根管充填糊剂iRoot SP行冷牙胶侧方加压充填;C、D组分别用生物陶瓷类根管充填糊剂iRoot SP和硅酮类根管充填糊剂Guttaflow行单尖充填;E、F组不添加糊剂只用牙胶尖侧方加压充填。将完成根管充填的实验组（每组10颗）和对照组浸入印度墨水中染色,其中4个实验组和阳性对照组在根尖孔周围2mm以外的牙体表面涂布2层指甲油,阴性对照组则在整个牙根表面涂布2层指甲油,采用透明牙法观察根尖微渗漏情况,使用imageJ软件测量并记录染色长度,并进行统计学分析;将剩余的样本横切后用扫描电镜对其截面进行观察。结果4个实验组所获得的浸墨长度分别为：A（1.02±0.46）mm, B（1.05±0.42）mm, C（1.02±0.45）mm, D（1.16±0.43）mm。4组浸墨长度之间的差异均无统计学意义（P〉0.05）。扫描电镜观察各组根管充填糊剂和根管壁牙本质之间均有缝隙。结论3种根管充填糊剂均不能完全封闭根管,在根尖封闭效果上无明显差异。     

Tissue reaction initiated by different sealers

AIMS: To analyse the type and degree of inflammatory reaction initiated by four sealers. METHODOLOGY: Twenty-four root canals of Macaca mulatta monkeys were filled within the canal and eight were overfilled with AH26, Apexit, Endomethasone or Grossman's sealers. The result of the treatment was evaluated after 6 months by histological assessment of the periapical tissues. RESULTS: In the group of root canals filled within the root, no inflammatory reaction was detected in specimens of Apexit and Grossman's sealers, but the other two sealers initiated different degrees of lymphocytic/plasmocytic tissue reactions. Endomethasone initiated a mild lymphocytic/plasmocytic reaction in three of the nine cases and AH26 caused mild lymphocytic/plasmocytic infiltration in two of the seven cases. In the group of overfilled root canals, all four sealers initiated inflammatory reactions. The periapical tissue reactions of overfilled root canals were similar to reactions detected in cases filled within the canal. However, additional histological features developed in specimens of Endomethasone and AH26: Endomethasone initiated a foreign body-type granulomatous reaction around the sealer particles and AH26 particles were engulfed by macrophages. The overfilled root canals of Apexit and Grossman's sealers initiated only lymphocytic/plasmocytic reactions. CONCLUSIONS: This study suggests that sealers with different chemical compositions initiate different histological reactions. It also emphasizes the importance of confining root filling to the canal system because all sealers initiate inflammatory reactions when they are present in the apical tissues     

氧化锌丁香油基质根管封闭剂的根尖封闭性能研究

目的:比较几种氧化锌丁香油基质根管封闭剂的根尖微渗漏情况,评价其封闭性能。方法:选择因正畸原因拔除的健康单根管前磨牙60颗,随机分成7个实验组(每组8颗)和2个对照组(每组2颗)。实验组分别采用6种氧化锌基质根管封闭剂(武汉大学口腔医院材料厂研制的1、2、3、4号氧化锌类糊剂,Pulp canal sealer糊剂及Endomethasone ivory糊剂)和一种树脂类封闭剂(Ah-Plus)作为根充糊剂,各组均采用冷牙胶侧方加压法充填根管。充填后采用印度墨汁染色处理,体式显微镜观察染料渗入的深度,进行统计分析比较。结果:7个实验组之间微渗漏情况无显著性差异,但Endomethasone ivory的微渗漏情况明显大于Ah-Plus。结论:在本实验条件下,研制的氧化锌基质根管封闭剂具有其他几种封闭剂同样的根尖封闭效果。     

Extended setting shrinkage behavior of endodontic sealers

The aim of this study was to investigate the polymerization shrinkage behavior of newly introduced root canal sealers. Three recently developed sealers; EndoRez (dual cure resin-based), RealSeal (dual cure resin-based), and GuttaFlow (silicon-based) were tested and compared with TubliSeal (zinc oxide-eugenol-based). The bonded disk method was used. Sixty specimens were tested at body and room temperatures. Dual cure resin-based sealers were tested as chemically cured only and as dual cured. Samples were tested for 24 hours. It was found that there were statistically significant differences between the tested sealers. EndoRez had the highest shrinkage-strain value, followed by RealSeal, whereas TubliSeal had the lowest. GuttaFlow exhibited expansion on polymerization. It was concluded that shrinkage associated with setting might jeopardize the seal of the root canal, leading to root canal failure.     

终末冲洗方案对根管封闭剂与根管壁牙本质粘接强度的影响

目的：比较不同终末冲洗方案对根管封闭剂 AH Plus 及 GuttaFlow 与根管壁牙本质之间粘接强度的影响。方法：60颗单根离体人牙截冠后用冠向下法进行常规根管机械化学预备,按终末冲洗方案随机分为3组（n ＝20）。组1：17％乙二胺四乙酸（EDTA）＋2％氯己定（CHX）;组2：5．25％次氯酸钠（NaOCl）＋17％ EDTA;组3：0．9％生理盐水（NS）对照组。每组根据使用的根管封闭剂分为2个亚组（n ＝10）：组 a．AH Plus;组 b．GuttaFlow。每个牙根自冠方向根方获取3个厚度约为2mm 的水平切片进行薄片推出实验。体视显微镜下观察断裂形式。结果：3种冲洗方案,AH Plus 的粘接强度均显著高于GuttaFlow（P ＜0．05）。使用 AH Plus 根管充填时,组1、组2和组3的粘接强度分别为（5．37±2．80）MPa、（8．81±4．38） MPa、（9．07±2．77）MPa（组1与组2或组3比较,P ＜0．05,组2与组3间比较,P ＞0．05）。使用 GuttaFlow 根管充填时,组1、组2和组3粘接强度分别为（1．40±0．59）MPa、（1．26±0．62）MPa 和（1．05±0．27）MPa（两两比较,P ＞0．05）。各组试件均以混合型断裂为主要断裂方式,但 GuttaFlow 组内粘接型断裂形式所占比例显著高于 AH Plus 组。结论：GuttaFlow 对牙本质的粘接强度显著低于 AH Plus。17％ EDTA ／2％ CHX 终末冲洗方案可显著降低 AH Plus 与根管壁牙本质的粘接强度,但对 GuttaFlow 的粘接性能无显著影响。     

GuttaFlow根管充填材料对人牙周膜成纤维细胞的毒性

目的:比较GuttaFlow常温流动牙胶根管充填材料与临床常用的两种根管封闭剂AH-Plus和Endomethasone的细胞毒性。方法:制备GuttaFlow、AH-Plus和Endomethasone浸提液,并将100%原液分别稀释至50%、25%和12.5%。组织块法培养人牙周膜成纤维细胞,将上述不同材料、不同浓度的浸提液与细胞共同培养,于1、3、5、7 d镜下观察细胞形态,MTT法分别检测各组细胞增殖情况,并计算相对增殖率(RGR)以评价细胞毒性。结果:AH-Plus和GuttaFlow各浓度组在各时点的细胞OD值均与对照组无明显差异,RGR分别为77.1%～14.1%和79.8%～115.9%,毒性评级均为0～Ⅰ级,评价结果为无细胞毒性,优于Endometha-sone。结论:GuttaFlow对人牙周膜成纤维细胞无明显细胞毒性。     

Release of formaldehyde by 4 endodontic sealers.

OBJECTIVE: The purpose of this study was to evaluate the release of formaldehyde by some root canal filling materials. STUDY DESIGN: Two older endodontic sealers, AH 26 and Endomethasone, and 2 recently available sealers, AH Plus and Top Seal, were analyzed. Infrared and electronic spectroscopy were used to determine formaldehyde content after set of the materials. RESULTS: Analysis showed that the AH 26 and Endomethasone sealers released formaldehyde. Although the AH Plus and Top Seal sealers have similar chemical composition, they released formaldehyde in a minimal concentration. CONCLUSIONS: The AH 26 and Endomethasone sealers released formaldehyde after setting; however, a minimum release was observed for the AH Plus and Top Seal sealers.     

The effect of human blood on the sealing ability of root canal sealers: an in vitro study

The effect of human blood and moisture contamination on the sealing ability of six commonly used root canal sealers was studied. The materials tested--Tubliseal, Diaket, AH26, Nogenol, Roth, and Endomethasone sealers--were placed in root canals with laterally condensed gutta-percha. The specimens were immediately immersed in blood or saline solution or kept dry for 2 hours. All the teeth were then subjected to methylene blue dye for 1 hour. A comparison of the seal was made by observation of dye penetration around the filling materials. Under all conditions, Tubliseal exhibited the least amount of marginal penetration, followed by AH 26. There was no significant difference in the depth of dye penetration between Diaket and Tubliseal in dry and wet conditions. Although AH 26, Nogenol, Roth, and Endomethasone sealers showed comparable sealing ability under dry conditions, the sealing ability of AH 26 and Diaket was superior to that of Nogenol, Roth, and Endomethasone sealers in moisture contamination. A significant drop in the seals afforded by AH26, Diaket, Roth, and Endomethasone sealers was recorded when these materials were immersed in blood. On the other hand, immersion in blood caused no significant change in the sealing ability of Nogenol.