Division of Restorative and Prosthetic Dentistry, The Ohio State University College of Dentistry, Columbus, USA.
J Prosthet Dent. 2011 Aug;106(2):118-25. doi: 10.1016/S0022-3913(11)60106-6.
Fracture of the interim partial denture may cause patient discomfort and result in unplanned appointments and expense. At present, limited information is available concerning the fracture toughness of bis-acryl interim resins, especially immediately following fabrication.
The purpose of this investigation was to evaluate the relative fracture toughness and Weibull parameters of 4 commercial chemically polymerized (Protemp Garant 3, Perfectemp II, Integrity, Temphase) and 1 dual polymerizing (Luxatemp Solar) bis-acryl interim resin materials with various filler loading after 1 hour and 24 hours.
Disk-shaped, mini-compact test specimens (8.20 × 1.85 mm thick, n=18) with introduced pre-cracks were prepared in a pre-heated split-mold and maintained at 37°C for 5 minutes during polymerization to simulate clinical conditions. Polymerization temperature was measured using an infrared digital thermometer. Specimens were stored in distilled water at 37°C after which the peak load to fracture was recorded at 1 and 24 hours and the fracture toughness (K(1c)) was calculated. An overall Weibull analysis of the fracture toughness was performed incorporating the fracture toughness data with factors polymerization method, time of testing and filler load of the resin. Weibull analysis was performed at (α =.05). Fracture surfaces of representative specimens were examined using scanning electron microscopy.
The overall Weibull analysis results showed significant differences (P<.001) in fracture toughness between the times of testing (1 and 24 hours), polymerization method, and as a function of filler loading. The results of the individual Weibull survival analyses showed a significant increase in Weibull Characteristic Strength (σo) values between 1 and 24 hours for all materials. The Weibull moduli (m) for the interim resins ranged between 5.8 and 10.3. SEM analysis of fractured surfaces revealed that crack propagation occurred primarily through the resin matrix between filler particles.
Post-gelation polymerization has an important role in determining the fracture properties of both chemical and dual-polymerized bis-acryl interim materials within the first 24 hours. For the materials tested, the higher the filler load, the lower the fracture toughness.
临时局部义齿的折断会引起患者不适，并导致计划外的就诊和费用增加。目前，关于双丙烯酸酯临时树脂的断裂韧性的信息有限，特别是在制造后立即。
本研究旨在评估 4 种商业化学聚合（Protemp Garant 3、Perfectemp II、Integrity、Temphase）和 1 种双重聚合（Luxatemp Solar）双丙烯酸酯临时树脂材料的相对断裂韧性和威布尔参数，这些材料的填充量各不相同，分别在 1 小时和 24 小时后进行评估。
在预热的分体模具中制备具有预制裂纹的圆盘形微型紧凑试件（8.20×1.85mm 厚，n=18），在聚合过程中在 37°C 下保持 5 分钟，以模拟临床条件。使用红外数字温度计测量聚合温度。聚合完成后，将试件在 37°C 的蒸馏水中储存，1 小时和 24 小时后记录断裂时的峰值载荷，并计算断裂韧性（K（1c））。采用整体威布尔分析方法，将树脂聚合方法、测试时间和填充量等因素纳入断裂韧性数据中，对断裂韧性进行分析。威布尔分析在（α=0.05）下进行。使用扫描电子显微镜对代表性试件的断裂表面进行了检查。
整体威布尔分析结果表明，测试时间（1 小时和 24 小时）、聚合方法以及填充量对断裂韧性有显著差异（P<.001）。个体威布尔生存分析结果表明，所有材料的威布尔特征强度（σo）值在 1 小时和 24 小时之间均显著增加。临时树脂的威布尔模数（m）范围在 5.8 到 10.3 之间。断裂表面的扫描电镜分析表明，裂纹扩展主要通过填充颗粒之间的树脂基体进行。
在最初的 24 小时内，后凝胶聚合对化学和双重聚合双丙烯酸酯临时材料的断裂性能有重要影响。对于测试的材料，填充量越高，断裂韧性越低。
