de Vasconcellos Luis Gustavo Oliveira, Nishioka Renato Sussumu, de Vasconcellos Luana Marotta Reis, Balducci Ivan, Kojima Alberto Noriyuki
From the Departments of *Dental Materials and Prosthodontics †Bioscience and Buccal Diagnosis, and ‡Social Dentistry and Children's Clinic, School of Dentistry of São José dos Campos, São Paulo State University (UNESP), São Jose dos Campos, Brazil.
J Craniofac Surg. 2013 Nov;24(6):e546-51. doi: 10.1097/SCS.0b013e31829ac83d.
The current study used strain gauge analysis to perform an in vitro evaluation of the effect of axial and non-axial loading on implant-supported fixed partial prostheses, varying the implant placement configurations and the loading points. Three internal hexagon implants were embedded in the center of each polyurethane block with in-line and offset placements. Microunit abutments were connected to the implants using a torque of 20 N · cm, and plastic prosthetic cylinders were screwed onto the abutments, which received standard patterns cast in Co-Cr alloy (n = 10). Four strain gauges (SGs) were bonded onto the surfaces of the blocks, tangentially to the implants: SG 01 mesially to implant 1, SG 02 and SG 03 mesially and distally to implant 2, respectively, and SG 04 distally to implant 3. Each metallic structure was screwed onto the abutments using a 10-N·cm torque, and axial and non-axial loads of 30 kg were applied at 5 predetermined points. The data obtained from the strain gauge analyses were analyzed statistically through the repeated measures analysis of variance and the Tukey test, with a conventional level of significance of P < 0.05. The results showed a statistically significant difference for the loading point (P = 0.0001), with point E (nonaxial) generating the highest microstrain (327.67 μ[Latin Small Letter Open E]) and point A (axial) generating the smallest microstrain (208.93 μ[Latin Small Letter Open E]). No statistically significant difference was found for implant placement configuration (P = 0.856). It was concluded that the offset implant placement did not reduce the magnitude of microstrain around the implants under axial and non-axial loading conditions, although loading location did influence this magnitude.
本研究采用应变片分析对轴向和非轴向加载对种植体支持的固定局部义齿的影响进行体外评估，改变种植体植入构型和加载点。将三个内六角种植体以直线排列和偏移排列方式嵌入每个聚氨酯块的中心。使用20 N·cm的扭矩将微型基台连接到种植体上，并将塑料修复圆柱体拧到基台上，这些基台接受钴铬合金铸造的标准牙型（n = 10）。四个应变片（SGs）粘贴在块体表面，与种植体相切：SG 01位于种植体1的近中，SG 02和SG 03分别位于种植体2的近中和远中，SG 04位于种植体3的远中。每个金属结构使用10 N·cm的扭矩拧到基台上，并在5个预定点施加30 kg的轴向和非轴向载荷。通过重复测量方差分析和Tukey检验对从应变片分析获得的数据进行统计学分析，显著性水平为P < 0.05。结果显示加载点存在统计学显著差异（P = 0.0001），点E（非轴向）产生的微应变最高（327.67 μ[拉丁小写字母开E]），点A（轴向）产生的微应变最小（208.93 μ[拉丁小写字母开E]）。种植体植入构型未发现统计学显著差异（P = 0.856）。得出的结论是，在轴向和非轴向加载条件下，偏移种植体植入并未降低种植体周围的微应变大小，尽管加载位置确实会影响该大小。
