干粘结和湿粘结对钛合金嵌体微渗漏的影响

目的对比3MESPE RelyXTMARC黏接水门汀在干燥和湿润两种状态下对钛合金嵌体微渗漏的影响。方法选择20颗因阻生新拔除的完整无隐裂、无磨耗的第三磨牙,随机分成2组,制备成邻牙合嵌体洞,分别在干燥和湿润两种状态下,用3MESPE RelyXTMARC黏接水门汀粘结钛合金嵌体,用体视显微镜观测嵌体密合度和嵌体微渗漏。结果两种粘接法嵌体密合度无显著差异(P>0.05),微渗漏深度有极显著差异(P<0.001)。结论以釉质壁为主的窝洞干粘结效果显著,以牙本质壁为主的窝洞湿粘结效果好。     

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??Objective    To evaluate the effect of various light-cured filling materials on marginal microleakage. Methods    The cuboid class ?? cavities were cut in 60 freshly extracted human premolars for orthodontic purpose in the Hospital of Stomatology affiliated to China Medical University from June to December of 2015??and they were randomly divided into 3 groups??filled with Z350 ??group A????Z350 preheat ??group B?? and SonicFill resin ??group C??. After placement of the restorations??each specimen was sectioned buccolingually and then the microleakage at the margin was evaluated under a stereomicroscope. Results    There was microleakage in all 3 groups. The microleakage of  group C was significantly slighter than the other two groups??P < 0.05????but there was no significant difference between group A and B??P > 0.05??. Conclusion    Marginal microleakage occurs in each of the 3 groups. SonicFill is the dental filling material with lesser marginal microleakage.     

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目的：通过对比4种牙本质黏结剂处理牙面后Ceramage聚合瓷嵌体的微渗漏程度,为黏结剂的临床选择提供参考。方法收集2012年7-9月在周口市第二人民医院口腔科因正畸需要拔除的牙体发育正常、无龋的前磨牙40颗,随机分为4组,每组10颗。40颗离体牙均按照嵌体备洞原则制备近中邻牙合Ⅱ类洞,Ceramage聚合瓷制作树脂嵌体,各组分别涂布牙本质黏结剂Prime＆Bond NT、Adper Single Bond 2、Clearfil SE Bond、Clearfil S3 Bond,用Rely X ARC树脂水门汀黏结嵌体。所有试件经冷热循环500次及品红染色后,金刚砂片平行于牙体长轴沿近远中方向将修复体纵向剖开2次,在体视显微镜下测量染料渗入轴壁、龈壁的深度。结果轴壁：4组的微渗漏程度比较,差异有统计学意义（F=8.3125,P〈0.01）;Clearfil S3 Bond组的微渗漏程度高于Clearfil SE Bond （q=5.7708）、Adper Single Bond 2（q=6.4032）和Prime＆Bond NT组（q=4.0316）,差异有统计学意义（P〈0.01）,而其他3组间差异无统计学意义（P〉0.05）。龈壁：不同黏结剂之间的微渗漏差异无统计学意义（F=0.5897,P〉0.05）。同种黏结剂的龈壁微渗漏程度均显著高于轴壁,配对t检验显示差异有统计学意义（P〈0.01）。结论Clearfil S3 Bond对牙釉质的封闭效果较差;从微渗漏深度大小和操作方法上进行评价,Clearfil SE Bond是黏结树脂嵌体较理想的牙本质黏结剂。     

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。     

两种碳酸饮料对烤瓷冠边缘微渗漏影响研究

目的　通过浸泡实验了解两种碳酸饮料对烤瓷冠边缘微渗漏的影响。方法　选取2017年7—8月于福建医科大学附属口腔医院口腔颌面外科门诊就诊的15例患者因正畸治疗需要拔除的前磨牙24颗。将拔除的前磨牙进行牙体预备,制作钴铬合金烤瓷冠,用树脂改性玻璃离子粘接剂粘固后随机均分为3组,分别为对照组、可乐组和雪碧组,每组8颗。对照组浸泡于人工唾液中,可乐组浸泡于可口可乐碳酸饮料中,雪碧组浸泡于雪碧碳酸饮料中,可乐组和雪碧组浸泡碳酸饮料的方法为每天3次,每次15 min,其余时间浸泡于人工唾液中。各组浸泡14 d后,用2%亚甲基蓝溶液浸泡染色,然后将其自颊舌向及近远中向顺牙体长轴剖开,体视显微镜下观察烤瓷冠边缘染料渗入情况,记录观测结果。结果　可乐组微渗漏程度大于雪碧组与对照组,差异有统计学意义（P < 0.05）。雪碧组微渗漏程度大于对照组,差异有统计学意义（P < 0.05）。结论　各组经14 d浸泡后均发生微渗漏,可乐组的微渗漏程度大于雪碧组与对照组,提示可口可乐碳酸饮料对烤瓷冠边缘微渗漏有较强的影响。     

Effect of the Nd:YAG laser on sealer penetration into root canal surfaces: A confocal microscope analysis

Objectives

The objective of this in vitro study was to evaluate the use of the Neodymium:Yttrium-Aluminium-Garnet (Nd:YAG) laser as part of the root canal treatment on the penetration of sealer into dentinal tubules.

Methods

Eighty extracted lower premolars were randomly assigned to two groups (n = 40 each): Control group (CG), subjected to a conventional protocol of endodontic instrumentation and obturation; and Laser group (LG), in which Nd:YAG laser irradiations were combined with conventional preparation and obturation. Endodonted samples were sectioned at 3 and 5 mm from the apex and observed under a confocal scanning microscope (CLSM). The penetration depth into the dentinal tubules and the extension of the intracanal perimeter infiltrated by sealer were measured. The Student–Newman–Keuls test was run for between-group comparisons (α = .05).

Results

The depth of sealer penetration into dentinal tubules did not differ among groups. LG samples showed the significantly highest percentage of penetrated perimeter at 3 mm from the root apex. Within each group, the greatest depth of penetration (P = .0001), and the major percentage of penetrated perimeter (P < .001), were recorded at 5 mm.

Conclusions

The application of the Nd:YAG laser after instrumentation did not improve the depth of sealer penetration into the dentinal tubules. The laser enlarged the total penetrable perimeter near the apex.

Clinical significance

The Nd:YAG laser may be an appropriate complement in root canal treatment, as it enhances the sealer adaptation to the dentinal walls in the proximity of the apex.     

不同间隔时间预备不同桩核系统对桩核微渗漏的影响

目的：研究不同间隔时间预备不同桩核系统对微渗漏的影响.方法：收集因正畸需要拔除的132颗下颌单根前磨牙,进行根管治疗、根管预备和桩核制作及粘结.132颗牙随机分为4组,分别在桩核粘固后5 min、15 min、30 min、24 h,阴性对照组进行牙体预备,每组内再随机分为铸造桩核磷酸锌粘固、铸造桩核聚羧酸锌粘固和玻璃纤维桩核树脂粘固亚组.每一标本进行染色法评价微渗漏情况.结果：相同的桩核系统中,渗漏值随着桩核粘固间隔时间的延长而降低;相同的间隔时间下,5 min、15 min和24 h时,纤维桩核系统的渗漏值最小,与其它两组比较均有统计学意义（P＜0.05）,30 min时铸造桩核磷酸锌粘固组与纤维桩核系统组无统计学意义（P＞0.05）.结论：不同间隔时间预备不同桩核系统对桩核微渗漏值有影响,为了桩核的稳固,应尽量在桩核粘固24 h后进行牙体预备.     

4种树脂材料体外模拟恒磨牙Ⅴ类洞充填后边缘封闭效果比较

目的：探讨新型自粘接流动树脂Constic与另外3种窝洞充填材料在恒磨牙体外实验中的边缘微渗漏情况,为临床Ⅴ类洞充填材料的选择提供参考。方法：收集新鲜离体恒前磨牙和第三磨牙各20颗,共40颗,颊面制备Ⅴ类洞,随机分为4组（n=10）,分别采用Constic自粘接流动树脂（Constic组）、Dyad Flow自粘接流动树脂（Dyad Flow组）、Filtek Z350XT流动树脂（Filtek Z350XT组）和Z350XT纳米树脂（Z350XT组）进行充填。每组随机选择5颗样本进行冷热循环100次,另5颗样本循环500次。0.1%罗丹明B荧光溶液染色后制片,采用激光共聚焦显微镜观察微渗漏情况,对微渗漏程度进行评估,并检测微渗漏深度。结果：各组材料均出现不同程度的边缘微渗漏。同种材料充填后冷热循环100和500次时微渗漏级别比较差异无统计学意义（P>0.05）。与Constic组比较,Dyad Flow组、Filtek Z350XT组和Z350XT组口壁及龈壁微渗漏深度明显增加（P<0.05）;Dyad Flow组和Filtek Z350XT组口壁及龈壁微渗漏深度均低于Z350XT组（P<0.05）。结论：自粘接流动树脂Constic微渗漏低,边缘密合度高,优于Dyad Flow、Filtek Z350XT和Z350XT。