Fracture Load of Anterior Acrylic Resin Provisional Fixed Partial Denture Reinforced with Fiber or Stainless Steel Wire

• Main Authors: Yu-Chi Wu, 吳育琦
• Other Authors: Jen-Chyan Wang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/93631540768433964670

碩士 === 高雄醫學大學 === 牙醫學研究所碩士班 === 95 === Fracture of provisional restorations is a common clinical problem, especially for long-span fixed partial dentures (FPDs). The function and esthetic demands of anterior provisional FPDs are essential considerations. The purpose of this study was to measure the fracture load and color cha- nge of anterior acrylic resin provisional FPDs reinforced with fibers or stainless steel wire, and to evaluate the effect of different types and lengths of reinforcements on fracture load, fracture patterns, and color change of samples. A total of 70 standardized 4-unit bridges over the maxillary anterior region were fabricated with PMMA resin. These were then divided into 7 equal groups (n=10); un-reinforced samples formed the control group. The experiment samples were reinforced with different length (4, 15mm) of three types of reinforcements (stainless steel wire, FibreKor, Construct). Color was measured according to CIE L*a*b* using a colorimeter, and color differences(ΔE) were calculated between the un-reinforced and reinforced samples. ΔE value was below the specific threshold (ΔE≥3), meaning that color difference was visually perceivable. All samples were subjected to thermocycling (600×5~55°C, 1min dwell time), following which the load was applied to samples using a universal testing machine until initial fracture. The fracture load and fracture pattern were recorded and the fracture surfaces of selective samples were observed under SEM. The results revealed that the group reinforced with 15mm stainless steel wire showed the highest mean fracture load (16.98±3.45kg) and the control group exhibited the lowest value (10.31±2.37kg). Statistical analysis by two-way ANOVA analysis of variance showed that the type and length of the reinforced material significantly influence fracture load (p<.0001), fracture pattern (p<.0001), and color change (p=0.0238). We conclude that samples reinforced with 15mm stainless steel wire result in a significantly higher fracture load and greater color difference as compared with samples reinforced with fibers. The use of 15mm stainless steel wire and fibers can change the fracture patterns of samples to ones that easily repaired .