Schneider Robert L, Curtis Erik R, Clancy James M S
Department of Prosthodontics, College of Dentistry, University of Iowa, Iowa City, Iowa 52242-1001, USA.
J Prosthet Dent. 2002 Aug;88(2):145-50. doi: 10.1067/mpr.2002.127898.
Fracture of acrylic resin prosthetic teeth from acrylic resin denture bases can be a problem for some patients. The optimal combination of acrylic resin denture tooth, denture base material, and processing method is not known. Purpose. The objective of this study was to compare the tensile bond strengths of heat- and microwave-polymerized acrylic resins among 4 types of acrylic resin denture teeth.
Heat-polymerized (Lucitone 199) and microwave-polymerized (Acron MC) acrylic resins were used. Four types of acrylic resin denture teeth (IPN, SLM, Vitapan, and SR-Orthotyp-PE) were milled to a fixed diameter according to ADA specification no. 15. Ten specimens of each tooth type were processed to each of the denture base materials according to the manufacturers' instructions. Ten additional resin control specimens without teeth also were fabricated. Specimens were thermocycled and tested for strength until fracture with a custom alignment device. Data were analyzed with analysis of variance and Duncan's multiple range test. A scanning electron microscope was used to identify adhesive and cohesive failures within debonded specimens.
The mean force required to fracture the specimens ranged from 5.3 +/- 3.01 to 21.6 +/- 5.2 MPa for the microwave-polymerized base and 11.2 +/- 3.0 to 39.1 +/- 5.1 MPa for the heat-polymerized base. The most common failure was cohesive within the denture tooth. With each base material, Orthotyp and IPN teeth exhibited the highest bond strengths; SLM and Orthotyp bond strengths were similar. In general, heat-polymerized groups failed cohesively within the denture base resin or the tooth, and microwave-polymerized groups failed adhesively at either the ridge lap or occlusal surface of the denture tooth.
Within the limitations of this study, the results suggest that the type of denture base material and denture tooth selected for use may influence the tensile bond strength of the tooth to the base. Selection of more compatible combinations of base and resin teeth may reduce the number of prosthesis fractures and resultant repairs.
对于一些患者来说，丙烯酸树脂假牙基托上的丙烯酸树脂假牙发生断裂可能是个问题。目前尚不清楚丙烯酸树脂假牙、假牙基托材料和加工方法的最佳组合。目的：本研究的目的是比较4种丙烯酸树脂假牙在热聚合和微波聚合丙烯酸树脂中的拉伸粘结强度。
使用热聚合（Lucitone 199）和微波聚合（Acron MC）丙烯酸树脂。根据ADA规范第15号，将4种丙烯酸树脂假牙（IPN、SLM、维他灵和SR-Orthotyp-PE）研磨成固定直径。按照制造商的说明，将每种牙齿类型的10个样本加工成每种假牙基托材料。还制作了另外10个无牙的树脂对照样本。对样本进行热循环处理，并使用定制的对准装置测试强度直至断裂。数据采用方差分析和邓肯多重极差检验进行分析。使用扫描电子显微镜识别脱粘样本中的粘结和内聚破坏。
对于微波聚合基托，使样本断裂所需的平均力范围为5.3±3.01至21.6±5.2MPa，对于热聚合基托为11.2±3.0至39.1±5.1MPa。最常见的破坏是假牙内的内聚破坏。对于每种基托材料，Orthotyp和IPN牙齿表现出最高的粘结强度；SLM和Orthotyp的粘结强度相似。一般来说，热聚合组在假牙基托树脂或牙齿内发生内聚破坏，而微波聚合组在假牙牙齿舌侧边缘或咬合面发生粘结破坏。
在本研究的局限性内，结果表明所选择使用的假牙基托材料和假牙类型可能会影响牙齿与基托之间的拉伸粘结强度。选择更兼容的基托和树脂牙齿组合可能会减少假体断裂和后续修复的次数。
