暂时冠桥材料抗压强度的体外实验研究

目的:对比分析5种暂时冠桥材料的抗压强度。方法:参照标准制作直径4 mm,高6 mm的圆柱形试件50个,甲基丙烯酸酯即自凝树脂(A组)、Integrity(B组)、Luxatemp(C组)、Temphase(D组)、Protem 3 Garan(tE组)5种暂时冠桥材料试件各10个,采用万能材料试验机测定其抗压强度,并进行统计分析。结果:A组抗压强度(210.28±20.07)MPa,显著低于其余4组(P<0.05),E组抗压强度最高(304.55±24.50)MPa,B、C、D组间无统计学差异(P>0.05),B、D、E组间也无显著性差异(P>0.05),C组和E组间抗压强度差异有统计学意义(P<0.05)。结论:5种暂时冠桥材料抗压强度间存在较大差异,Bis-acryl类材料较甲基丙烯酸酯类材料抗压强度高。     

LED固化灯光照强度对光固化复合树脂聚合收缩的影响

目的采用数字图像相关法动态研究LED光固化灯不同光照强度对光固化复合树脂聚合收缩的影响。方法收集12颗大小接近的新鲜离体磨牙,随机分为3组,制备大小为2.0 mm×2.0 mm×2.0mm的邻(?)面洞形,洞面酸蚀冲洗后涂粘接剂光照10 s,充填3M Z350纳米复合树脂,邻面快速制造散斑,LED固化灯垂直(?)面光照40s,3组光照强度分别为300 mW/cm~2、500 mW/cm~2和800 mW/cm~2,数码相机同步实时采集光照过程中试件表面散斑的变化序列图像,用数字图像相关法计算获得各序列图上逐个像素点水平方向(x)和垂直方向(y)位移,统计线性收缩率,描绘各像素点的时域变化曲线,并用SPSS 12.01统计软件包进行方差分析和配对t检验。结果 3种光照强度下树脂x方向线收缩率分别为0.081%～0.486%、0.004%～0.316%和0.063%～0.560%,y方向线收缩率分别为0.088%～0.981%、0.003%～0.77%和0.157%～1.252%,3组之间差异有统计学意义(P<0.05);3组第20 s树脂游离面收缩x方向位移差异无统计学意义,y方向位移差异有统计学意义。结论 LED光固化灯500 mW/cm~2光照时引起的树脂聚合收缩最小。     

Influence of high expansion dental stone used as investing medium on the changes in occlusal vertical dimension of complete dentures

Problem statementDespite advances in materials and techniques, complete dentures made of acrylic resin experience an increase in the occlusal vertical dimension (OVD) during processing. Many factors that affect the OVD of complete dentures are known. However, no study has examined the effect of using high-expansion dental stone (type V) as an investing material on the OVD.PurposeThis study investigated the effects of using a high-expansion dental stone as an investing material on changes in the OVD of complete dentures.Material and methodsTwenty sets of simulated upper and lower dentures were processed by the compression molding technique. Specimens were equally divided into 2 groups. In the dental stone type III (DST III) group, the lower, middle, and upper parts of a flask were filled with DST III. In the dental stone type V (DST V) group, the procedure was the same as in the DST III group, except that the middle layer was made of high-expansion DST V. Changes in the OVD were measured before and after denture processing. Collected data were analyzed with t-test statistics. Differences were considered statistically significant at the 95% confidence level.ResultsBoth groups showed a small increase in the OVD as a result of processing, but the OVD increase was significantly less in the DST V group compared to the DST III group.ConclusionHigh-expansion DST V can be recommended as an investing material to reduce the increase in the OVD that may occur while processing complete dentures.     

复合树脂联合脱敏剂对楔状缺损牙敏感性及修复疗效的影响

目的：评价复合树脂充填楔状缺损时,联合应用脱敏剂对术后敏感和远期临床疗效的影响。方法：将167例542颗因楔状缺损导致牙本质敏感的患者按简单随机化分组方法,分为三组：涂布iBond七代自酸蚀粘接剂后复合树脂充填（A组）、涂布自酸蚀粘接剂可乐丽菲露后复合树脂充填（B组）及涂布舒齿灵脱敏剂后涂布可乐丽粘接剂七代自酸蚀粘接剂后复合树脂充填（C组）,比较术后脱敏疗效,并于充填后6、12及24个月用改良USPHS系统评价其远期临床疗效。结果：楔状缺损修补术后,各组牙牙本质敏感症状均有明显的缓解（尸〈0．05）;无牙本质敏感症状的牙所占比例A、C组显著性高于B组（P〈0．05）;三组在6、12个月时充填体成功率无显著差异,但C组24个月修复体成功率显著性低于A,B组。结论：对因牙本质敏感求治的楔状缺损患者,推荐术前使用脱敏剂或使用含有脱敏成分的粘接剂;使用iBond粘接剂进行复合树脂充填,能显著减少牙敏感症状,并且具有良好的粘接性能。     

Influence of silane and solvated bonding agents on the bond strength to glass‐fibre posts

The combined use of silane and solvated bonding agents on the bond strength to glass‐fibre posts was investigated. A model Bis‐GMA/HEMA adhesive was formulated with no solvent, 30% of ethanol or 80% of acetone. The surfaces of rectangular‐shaped posts were silanated or not and one of the agents was applied, except for the control group. Cylinders of resin cement (RelyX ARC, 3M ESPE, Saint Paul, MN, USA) were built‐up on the surfaces (n = 20) and submitted to shear testing. All groups showed higher bond strengths when the surfaces were silanated. When no silanization was carried out, the use of bonding agents, either solvated or non‐solvated, increased the bond strengths. All groups treated with both silane and bonding agent showed higher bond strengths than the group that was only silanated. Control and ethanol‐based adhesives were similar, whereas the acetone‐based agent yielded higher bond strengths. Adhesive failures were predominant. Combination of silane and adhesive enhanced the bond to fibre posts.     

���ܳ�����ϱ�Ե΢��©����ʵ���о�

目的对比4种充填材料的边缘微渗漏情况,为其临床应用提供合理指导。方法选择2013年1—6月青岛大学医学院附属医院口腔科因牙周病或阻生齿而拔除的健康新鲜后牙60颗,备洞后随机分为6组,每组10颗,分别使用Fihek Z250复合树脂（A1、A2组）、Ketac N100树脂加强型玻璃离子（B1组）、Ketac MolarEasymix型玻璃离子（B2、B3组）、F2000Compomer玻璃离子复合体（B4组）充填窝洞。其中A2组充填后充填体表面涂布AdperSingleBond2粘接剂,B3组充填后充填体表面涂布凡士林,而其他各组充填后表面不做任何处理。经冷热交替实验后,记录各组染料渗入窝洞壁与充填体之间的深度,并进行统计分析。结果A2组微渗漏最小,B2组微渗漏最大,与其他组（A1、B1、B3、B4）相比差异有统计学意义（P〈0．05）;A1、B1、B3、B4组间两两比较差异均无统计学意义（P〉0．05）。结论复合树脂、树脂加强型玻璃离子、玻璃离子复合体的边缘微渗漏均小于传统型玻璃离子;表面涂布隔湿剂后能增强上述材料的边缘封闭性能。     

金属翼板树脂粘接固定义齿的临床应用

金属翼板树脂粘接固定义齿是以铸造金属为支架,金属翼板为固位体,烤瓷熔附金属为桥体的粘接固定桥,是目前应用最多的一种粘接桥修复方法。其主要缺点是远期留存率较低,最常见的失败原因是脱胶,具体表现为脱落或松动,脱落率高成为限制发展的主要因素。影响其成功率的因素众多,本文就病例选择、固位体设计和连接体三个方面对粘接桥的影响作一综述,以供临床参考。     

不同树脂嵌体材料边缘微渗漏的对比研究

目的：通过对比4种树脂嵌体材料的微渗漏大小,为临床树脂嵌体材料的选择提供参考.方法：40颗离体牙按嵌体备洞原则制备近中邻（牙合）Ⅱ类洞,随机分为4组,每组10颗.分别用Z350、P60、Ceramage、Solitaire 2制作嵌体后使用Adper Single Bond 2和Adper Rely X ARC进行粘结.经冷热循环500次品红染色后,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,在体式显微镜下测量染料渗入轴壁、龈壁的深度.结果：4组树脂嵌体材料轴壁和龈壁均出现微渗漏.经单因素方差分析,不同树脂嵌体材料之间的轴壁（F=0.131）及龈壁（F=0.385）微渗漏差异无统计学意义（P＞0.05）;同材料组的龈方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：从微渗漏深度大小来进行评价,4种树脂嵌体材料均是临床上制作树脂嵌体理想的材料;树脂嵌体与牙釉质粘结效果比牙本质好.