Interim restorations are essential in fixed prosthodontics as they provide temporary protection of teeth before the insertion of the permanent restoration. Poly(methyl methacrylate) (PMMA) is widely used in the fabrication of interim-fixed restorations as it is a biocompatible material with a lot of convenient properties. However, it exhibits low impact and tensile strength and therefore it is necessary to be reinforced. Calcium β-pyrophosphate (β-CPP) is considered a promising reinforcing material for dental applications, especially for enamel regeneration due to its stability at low pH and its low wear rate. The aim of this study was to manufacture PMMA/β-CPP composites suitable for fixed-interim restorations and to study their mechanical and thermal properties. In order to enhance β-CPP dispersion into PMMA matrix, ball-milling was performed for 1 or 6 h. Three-point bending test was performed to study flexural strength, Dynamic Mechanical Analysis (DMA) to reveal the elastic and viscous moduli along with T_g, Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction Analysis (XRD) to investigate the structure of the materials and SEM for the morphological evaluation of both composite powders and polymerized specimens. Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) experiments were performed to study their thermal properties. A statistically significant increase in flexural strength was found in the 0.5, 0.75 and 1% composite groups after 6 h ball-milling, relative to the control, with the 6 h ball milling mixed specimens, presenting the highest flexural strength values. The brittle fracture type was common to all groups. An obvious improvement of the mechanical properties and a slight improvement in the thermal stability of the composite materials values were also observed as β-CPP content was increased, while T_g values were statistically not-affected.

临时修复体对于固定修复体至关重要，因为它们在插入永久修复体之前为牙齿提供了临时保护。聚甲基丙烯酸甲酯（PMMA）是一种生物相容性材料，具有许多便利的特性，因此被广泛用于临时固定修复体的制造中。但是，它显示出低的冲击强度和抗张强度，因此必须进行增强。钙β焦磷酸（β -CPP）被认为是用于牙科应用的有前途的加强材料，特别是对于搪瓷再生由于其在低pH下的稳定性和它的低磨损率。这项研究的目的是制造PMMA / β-CPP复合材料适用于固定中期修复，并研究其机械和热性能。为了增强β- CPP在PMMA基质中的分散，进行了1或6 h的球磨。进行三点弯曲试验以研究弯曲强度，动态力学分析（DMA）揭示了弹性模量和粘滞模量以及T _g，傅里叶变换红外光谱（FTIR）和X射线衍射分析（XRD）来研究材料的结构和SEM，以便对复合粉末和聚合样品的形态进行评估。进行热重分析（TGA）和差示扫描量热法（DSC）实验以研究其热性能。与对照组相比，球磨6 h后0.5、0.75和1％的复合材料组的抗弯强度在统计学上有显着提高，相对于对照组，6 h球磨混合标本具有最高的抗弯强度值。脆性骨折类型在所有组中都是常见的。观察到复合材料的机械性能有明显改善，热稳定性稍有改善，以β表示-CPP含量增加，而T _g值在统计学上不受影响。