Zanardi Piero Rocha, Stegun Roberto Chaib, Sesma Newton, Costa Bruno, Shibli Jamil Awad, Laganá Dalva Cruz
*Department of Periodontology and Oral Implantology, Dental Research Division, Guarulhos University, Guarulhos †Department of Prosthodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil.
J Craniofac Surg. 2015 Oct;26(7):2163-6. doi: 10.1097/SCS.0000000000002119.
The progressive bone loss at the neck of dental implant is a clinical concern since it affects the maintenance of dental aesthetics. The current study evaluated the influence of insertion depth, prosthetic connection, and type of loading on the stress distribution around dental implants, using photoelastic evaluation.
A total of three blocks of photoelastic resin for each type of implant connection (external hexagon, external hexagon flattened, internal hexagon, and Morse taper) were built. Each block differed in the position of the implant platform in relative to the upper margin of the block: I (2 mm below), II (at the same level), and III (2 mm above). A force of 100 N was applied to both straight and tilted abutments. Totally, 4 selected points were evaluated at 1 side of the implant. Quantitative data were collected for the statistical analysis.
A multiple linear regression showed the relation between the stress distribution and the insertion depth. For all the implant types, both with straight and tilted abutments, group I presented the lowest stress concentration around the fixture when compared with group II and III (P < 0.05).
Within the limitations of this study, it could be concluded that the deeper the insertion, the lower the stress concentration.
牙种植体颈部的渐进性骨丢失是一个临床问题，因为它会影响牙齿美观的维持。本研究采用光弹性评估方法，评估了植入深度、修复连接方式和加载类型对牙种植体周围应力分布的影响。
针对每种种植体连接类型（外六角形、扁平外六角形、内六角形和莫氏锥度）制作了总共三块光弹性树脂块。每个树脂块中种植体平台相对于树脂块上边缘的位置不同：I（下方2毫米）、II（同一水平）和III（上方2毫米）。对直基台和倾斜基台均施加100 N的力。总共在种植体的一侧评估4个选定的点。收集定量数据进行统计分析。
多元线性回归显示了应力分布与植入深度之间的关系。对于所有种植体类型，无论是直基台还是倾斜基台，与II组和III组相比，I组在种植体周围的应力集中最低（P < 0.05）。
在本研究的局限性范围内，可以得出结论，植入越深，应力集中越低。
