Falland-Cheung Lisa, Pittar Nicholas, Tong Darryl, Waddell J Neil
Sir John Walsh Research Institute, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand.
Forensic Sci Med Pathol. 2015 Dec;11(4):552-7. doi: 10.1007/s12024-015-9718-0. Epub 2015 Oct 5.
The purpose of this study was to measure the tear strength and hardness of four different dental silicones in comparison to that of porcine skin.
Specimens were prepared (n = 20/group) according to ASTM D624-00, using three hydrophilic vinyl polysiloxane impression materials, one duplication silicone, and fresh porcine skin. A universal testing machine was used to strain each test specimen until complete rupture and calculate its tear strength (kNm(-1)). Failure analysis was then conducted using a stereoscopic zoom light microscope, as well as a scanning electron microscope (SEM). A shore A-type durometer was used to measure the hardness of all specimens.
The tear strength for the silicones ranged from 1.75 to 9.58 kNm(-1) and the pigskin from 3.65 to 56.40 kNm(-1). The mean shore hardness for the silicones ranged from 16.275 to 62.65DU and the pigskin had a mean shore hardness of 22.65DU, with p values <0.0125 (0.05/4). Failure analysis of the silicone materials showed the origin of failure being in the tension side of the specimens and typical failure patterns were observed. Examining the materials under a SEM revealed that materials with higher viscosity presented with a larger amount of filler particle content than silicones with low viscosity, with the duplication silicone having no filler content.
Dental silicones are a good alternative for skin in studies that require a skin simulant.
本研究的目的是测量四种不同牙科硅橡胶与猪皮相比的撕裂强度和硬度。
根据ASTM D624 - 00制备样本（每组n = 20），使用三种亲水性乙烯基聚硅氧烷印模材料、一种复制硅橡胶和新鲜猪皮。使用万能试验机对每个测试样本进行拉伸直至完全破裂，并计算其撕裂强度（kNm(-1)）。然后使用立体变焦光学显微镜以及扫描电子显微镜（SEM）进行失效分析。使用邵氏A型硬度计测量所有样本的硬度。
硅橡胶的撕裂强度范围为1.75至9.58 kNm(-1)，猪皮的撕裂强度范围为3.65至56.40 kNm(-1)。硅橡胶的平均邵氏硬度范围为16.275至62.65DU，猪皮的平均邵氏硬度为22.65DU，p值<0.0125（0.05/4）。硅橡胶材料的失效分析表明，失效起源于样本的拉伸侧，并观察到典型的失效模式。在扫描电子显微镜下检查材料发现，与低粘度硅橡胶相比，高粘度材料的填料颗粒含量更多，而复制硅橡胶没有填料含量。
在需要皮肤模拟物的研究中，牙科硅橡胶是皮肤的良好替代品。
