不同类型瓷贴面与树脂水门汀对贴面密合度与微渗漏的影响

目的:观察瓷贴面类型及树脂水门汀对瓷贴面边缘密合度及微渗漏的影响。方法:36颗上颌中切牙随机均分为四组进行贴面修复,A组:IPS e.max Press瓷贴面+RelyXTM Veneer树脂水门汀;B组:IPS e.max Press瓷贴面+Vitique树脂水门汀;C组:CAD/CAM长石质瓷贴面+RelyXTM Veneer树脂水门汀;D组:CAD/CAM长石质瓷贴面+Vitique树脂水门汀。贴面粘接后经冷热循环老化、亚甲基蓝染色,在显微镜下观测贴面唇面中央及近远中轴角区纵截面边缘密合度及微渗漏情况。结果:A、B、C、D组平均密合度分别为(0.037±0.007)mm、(0.044±0.012)mm、(0.046±0.014)mm、(0.038±0.004)mm,龈边缘染料渗入平均深度分别为(0.143±0.085)mm、(0.148±0.087)mm、(0.236±0.074)mm、(0.158±0.036)mm,组间均无显著差异。B、C、D组近远中轴角区微渗漏情况重于唇面正中区。结论:单颗贴面内部不同区域密合度较一致,但近远中轴角区微渗漏情况更严重,贴面类型及树脂水门汀对瓷贴面平均边缘密合度及微渗漏无显著影响。     

3D打印陶瓷技术在口腔医学领域的研究进展

全瓷修复体具有良好的生物相容性、美观性及力学性能,备受患者青睐,已成为固定修复的主流方式。以数控切削成型为代表的减材制造和失蜡铸造为代表的等材制造工艺发展成熟,但仍有不足之处。随着数字化时代的到来,运用3D打印技术制造的烤瓷修复体、可摘局部义齿、种植导板已应用于临床,而3D打印全瓷修复体尚处于研究阶段。文章将简要介绍各种3D打印陶瓷技术的工作原理、研究现状及优缺点,并对其发展进行展望。     

Response of two gingival cell lines to CAD/CAM composite blocks

ObjectiveThis study aimed to investigate the influence of CAD/CAM composite materials on human gingival fibroblasts (HGF) and gingival keratinocytes (HGK).MethodsFour materials were investigated: two resin-composite blocks (RCB), Grandio Blocs (GR) and Block HC (HC); one polymer-infiltrated ceramic network (PICN) (Enamic, EN); and one conventional resin-composite, Grandioso (GND). HGF and HGK were cultured as per the supplier’s protocol (ATCC, UK). Cell proliferation and cytotoxicity were evaluated at 1, 3, 5 and 10 days using LDH and Alamar Blue assays. Indirect immunostaining was used to assess the Caspase-3 activity. Data were analysed via two-way ANOVA, one-way ANOVA and Tukey’s post hoc test (α = 0.05 for all tests).ResultsThere was significant difference in cell proliferation of the HGK and HGF cells in contact with different composite materials but no significant differences in their cytotoxicity. There was a significant effect on cell proliferation and cytotoxicity with different exposure times, for each type of resin-composite. HGF cell proliferation was higher than HGK with almost all investigated materials and at all time points. No Caspase-3 activity was detected in either cell lines.SignificanceHGK proliferation and cytotoxicity appeared to be more influenced by composite materials compared to HGF, demonstrating EN cytotoxic effects in HGK. Different manufacturing techniques of resin-composites (photo curing versus heat/pressure curing) had no significant effect on their biocompatibility.     

离体下颌前磨牙预备状况与贴面抗折性的关系

目的:旨在比较下颌前磨牙牙体预备和不预备后制备全瓷贴面和复合树脂贴面的抗折力。方法:40个新鲜离体下颌前磨牙随机分为4组(n=10):NPR组(牙体不预备直接0.2 mm厚树脂贴面修复);NPC组(牙体不预备直接0.2 mm厚铸瓷贴面修复);P2C组(牙体预备0.2 mm,修复0.2 mm厚铸瓷贴面);P5C组(牙体预备0.5 mm,修复0.5 mm厚铸瓷贴面),预备面均包绕颊侧延伸颌面1 mm。所有试件常规粘接后进行冷热循环实验(10000次/5~55℃),在万能材料试验机下进行抗折测试(2 KN,0.5 mm/min),断裂面放大10倍分析,数据方差检验。结果:各组抗折力均值分别为:NPR=(690.33±233),NPC=(790.52±408),P2C=(1131.34±341),P5C=(983.56±202)。所有组均有统计学差异(P<0.05),NPR、NPC组抗折力均小于P2C,然后P5C组抗折力与其余各组差距不明显。断裂分析显示断裂面呈现混合断裂(60%),内聚断裂(20%),根裂(15%),粘接断裂(5%)。结论:微量(0.2 mm)的前磨牙牙体预备后修复全瓷贴面可获得最大抗折力,当预备超过0.5 mm时可能会发生牙体折裂。     

Ceramic on ceramic hip arthroplasty in fused hips

Background:Most literature in the field of total hip arthroplasty (THA) for fused hips, until date has reported the results of using metal on polyethylene and ceramic on polyethylene bearings. Results of THA using ceramic on ceramic (CoC) bearings in fused hips have not been published in literature. This study reports the results of cementless THA using CoC articulation perfomed in fused hips.Results:Mean Harris hip score improved from 42.4 to 84.2 and mean leg lengthening of 36.6 mm was achieved. In the average 5.4 years (range 2.8-9.1 years) followup there were no cases with osteolysis around acetabular cup and femoral stem. In this study, there was no case of ceramic fracture. There was one case of squeaking.Conclusion:This study suggests that cementless THA performed for fused hips with CoC bearings can provide good early clinical results.