ABSTRACT

This research aims to identify the suitable and optimum filler loading to improve the polymethyl methacrylate (PMMA) properties for denture application. Mechanical properties were determined based on the flexural, fracture toughness, hardness and impact strength. The first stage investigated the effect of different weight loadings of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP). The addition of 2 wt-% HA in PMMA composites increased the flexural and fracture toughness when compared with β-TCP composites. The addition of β-TCP in PMMA composites increased the mechanical properties at higher filler loading; 4 and 6 wt-%. The second stage investigated the effect of hybrid fillers; HA/polylactic acid (PLA) microsphere and HA/alumina (Al₂O₃). HA/PLA microsphere in PMMA showed 5% and 23% improvement on the fracture toughness and impact strength if compared to PMMA/2 wt-% HA. HA/Al₂O₃ in PMMA showed higher flexural strength. The mechanical properties of a single filler can be further improved by hybrid fillers.

摘要

本研究旨在确定合适和最佳的填料填充量，以改善用于义齿应用的聚甲基丙烯酸甲酯 (PMMA) 性能。基于弯曲、断裂韧性、硬度和冲击强度确定机械性能。第一阶段研究了不同重量负载的羟基磷灰石 (HA) 和 β-磷酸三钙 (β-TCP) 的影响。与 β-TCP 复合材料相比，在 PMMA 复合材料中添加 2 wt-% HA 增加了弯曲和断裂韧性。在 PMMA 复合材料中添加 β-TCP 提高了填料填充量下的机械性能；4 和 6 重量％。第二阶段研究混合填料的效果；HA/聚乳酸 (PLA) 微球和 HA/氧化铝 (Al ₂ O ₃）。与 PMMA/2 wt-% HA 相比，PMMA 中的 HA/PLA 微球的断裂韧性和冲击强度分别提高了 5% 和 23%。PMMA中的HA/Al ₂ O ₃表现出更高的弯曲强度。混合填料可以进一步提高单一填料的机械性能。