背景:评估数字铣削和印刷义齿基托材料的弯曲强度。
方法:测试的材料是Lucitone199义齿基托盘(DentsplySirona),AvaDent义齿基托圆盘(AvaDent),KeyMill义齿基托盘(Keystone),Lucitone数码印花义齿基托树脂(DentsplySirona),Formlab义齿基托树脂(Formlabs),和Dentca基树脂II(Dentca)。制备每种材料的60个棒状试样进行抗弯强度测试,并分为五组:对照组,热循环,疲劳循环,并使用两种不同的材料进行修复。使用在具有1kN测压元件的Instron万能测试机上进行的三点弯曲测试来测试挠曲强度和模量。样品在具有垂直对准的加载装置下居中。加载速率为0.5mm/min的十字头速度。每个样品加载力直到发生失效。采用单因素方差分析检验对数据进行分析,其次是Tukey的HSD检验(α=0.05)。
结果:经研磨的材料表现出比印刷材料更高的挠曲强度。热循环和疲劳降低了印刷和研磨材料的挠曲强度。修复组的抗弯强度为印刷和铣削材料的原始抗弯强度的32.80%和30.67%,分别。然而,修复材料的类型影响印刷材料的弯曲强度;复合树脂显示出比丙烯酸树脂更高的弯曲强度值。
结论:磨制的义齿基托材料显示出比印刷基托材料更高的弯曲强度。
BACKGROUND: To evaluate the flexural strength of digitally milled and printed denture base materials.
METHODS: The materials tested were Lucitone 199 denture base disc (Dentsply Sirona), AvaDent denture base puck (AvaDent), KeyMill denture base disc (Keystone), Lucitone digital print denture base resin (Dentsply Sirona), Formlab denture base resin (Formlabs), and Dentca base resin II (Dentca). Sixty bar-shaped specimens of each material were prepared for flexural strength testing and were divided into five groups: control, thermocycled, fatigue cycled, and repair using two different materials. The flexural strength and modulus were tested using a 3-point bend test performed on an Instron Universal Testing Machine with a 1kN load cell. The specimens were centered under a loading apparatus with a perpendicular alignment. The loading rate was a crosshead speed of 0.5 mm/min. Each specimen was loaded with a force until failure occurred. A one-way ANOVA test was used to analyze the data, followed by Tukey\'s HSD test (α = 0.05).
RESULTS: The milled materials exhibited higher flexural strength than the printed materials. Thermocycling and fatigue reduce the flexural strengths of printed and milled materials. The repaired groups exhibited flexural strengths of 32.80% and 30.67% of the original flexural strengths of printed and milled materials, respectively. Nevertheless, the type of repair material affected the flexural strength of the printed materials; the composite resin exhibited higher flexural strength values than the acrylic resin.
CONCLUSIONS: The milled denture base materials showed higher flexural strength than the printed ones.