Objectives

The purpose of this study was to investigate the fracture resistance, flexural strength and Weibull modulus of an innovative CAD/CAM polymer and to compare its fracture resistance with that of glass ceramics.

Materials and methods

A total of 32 (n = 16 IPS e.max CAD (LIDI); n = 16 LuxaCam Composite (LUXA)) first mandibular molar crowns were fabricated and cemented onto metal dies by use of luting composite. Half of the specimens were loaded until fracture without prior artificial ageing. The other half were subjected to thermal (5°/55 °C) and mechanical (1,200,000 cycles, 80 N) cycling before fracture loading. Scanning electron microscopy was used to analyse fracture behaviour. A three-point bending test of the flexural strength of LUXA was performed according to ISO 6872:2008. Data were analysed by means of the Kolmogorov–Smirnov test, Mann–Whitney U-test (p < 0.05) and Weibull statistical analysis.

Results

Initial fracture resistance of LIDI was significantly higher than that of LUXA. However, the initial fracture resistance of LIDI decreased significantly after artificial ageing. After ageing, fracture resistance was 1050.29 ± 325.08 N for LUXA and 1250.09 ± 32.53 N for LIDI. Three-point bending test yielded a mean flexural strength value for LUXA of 145.28 ± 18.21 MPa and a Weibull modulus of m = 9.51.

Conclusions

Polymer-based material tested in this study had a lower fracture resistance than that of the glass-ceramic material. Fracture resistance and flexural strength of LuxaCam Composite are sufficient for use in the first molar region.

Clinical relevance

The mechanical properties of this innovative polymer-based material indicate it can be used in the first molar region as a suitable alternative to glass ceramics. Further clinical studies are required to confirm this.

The study presents an innovative material as an alternative to glassceramic for the clinical use in dentistry. The materials investigated were differently affected by artificial aging. Clinical use for patients with bruxism may be considered.

中文翻译：

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CAD / CAM聚合物冠的抗弯强度以及人工时效对CAD / CAM聚合物和陶瓷单冠抗断裂性的影响。

目标

这项研究的目的是研究一种创新的CAD / CAM聚合物的抗断裂性，抗弯强度和威布尔模量，并将其与玻璃陶瓷的抗断裂性进行比较。

材料和方法

总共制造了32个（n  = 16 IPS e.max CAD（LIDI）；n  = 16 LuxaCam复合材料（LUXA））的第一下颌磨牙冠，并通过使用胶合剂将其粘结到金属模具上。一半的样品被加载直至破裂，而无需事先人工老化。另一半在断裂载荷之前经历了热（5°/ 55°C）和机械（1,200,000个循环，80 N）循环。扫描电子显微镜用于分析断裂行为。根据ISO 6872：2008对LUXA的抗弯强度进行了三点弯曲测试。数据通过Kolmogorov–Smirnov检验，Mann–Whitney U检验（p  <0.05）和Weibull统计分析进行分析。

结果

LIDI的初始抗断裂性明显高于LUXA。但是，人工老化后，LIDI的初始抗断裂性明显降低。老化后，LUXA的抗断裂性为1050.29±325.08 N，LIDI为1250.09±32.53N。三点弯曲试验得出的LUXA的平均抗弯强度值为145.28±18.21 MPa，魏布尔模量为m  = 9.51。

结论

在这项研究中测试的聚合物基材料的抗断裂性低于玻璃陶瓷材料。LuxaCam复合材料的抗断裂性和抗弯强度足以用于第一磨牙区域。

临床相关性

这种创新的基于聚合物的材料的机械性能表明，它可以在第一磨牙区域用作玻璃陶瓷的合适替代品。需要进一步的临床研究以证实这一点。

这项研究提出了一种创新的材料，可以替代牙科用玻璃陶瓷，用于临床。所研究的材料受到人工时效的影响不同。可以考虑磨牙症患者的临床使用。