Martins Caio Marques, Ramos Elimário Venturin, Kreve Simone, de Carvalho Geraldo Alberto Pinheiro, Franco Aline Batista Gonçalves, de Macedo Luís Guilherme Scavone, Silva Alecsandro de Moura, Dias Sérgio Candido
Department of Prosthodontics and Restorative Dentistry, São Leopoldo Mandic Dental Research Center, Campinas, Brazil.
Department of Oral Rehabilitation, UNESP, São José dos Campos, São Paulo, Brazil.
Dent Res J (Isfahan). 2019 Mar-Apr;16(2):110-116.
This experimental study assessed reverse torque of indexed and nonindexed (NI) abutments in Morse Taper (MT) implants in a mechanical fatigue test.
In this experimental study It was used 37 implants MT and over them installed Pilar Flex abutments (4.8 mm × 6 mm × 1.5 mm). The groups were as follows: Group A used 19 MT implants with a NI Pilar Flex abutment loaded with 32 N/cm and Group B used 18 MT implants with an indexed (IN) Pilar Flex abutment loaded with 20 N/cm. The abutments were tested according to ISO standard 14801/2007. The specimens were installed at 30° from the axial axis and underwent a 133 N load, 4 Hz frequency, and 1,000,000 cycles. Once the test was completed, the reverse torque was provided by an electronic torque meter. Data were submitted to statistical analysis using the -test for independent samples and paired -test. The significance level was considered < 0.05.
Results obtained showed that the indexed Pilar Flex abutment had a percentage of torque loss from the initial torque of 49% and the NI Pilar Flex abutment lost 14%. Paired Student's -tests revealed that for both NI ( < 0.001) and indexed ( < 0.001) abutments, the counter torque values were significantly lower than those applied at the initial torque.
According on the methodology used, the NI Pilar Flex abutment was more effective regarding the reverse torque in single-unit implant prostheses versus the indexed Pilar Flex abutment. A greater loosening in the indexed Pilar Flex abutment retaining screw was noted in the reverse torque test, and the Pilar Flex abutment failed to show good outcomes related to the cold welding effect.
本实验研究在机械疲劳试验中评估了莫氏锥度（MT）种植体中带定位和不带定位（NI）基台的反向扭矩。
在本实验研究中，使用了37颗MT种植体，并在其上安装了Pilar Flex基台（4.8毫米×6毫米×1.5毫米）。分组如下：A组使用19颗带有NI Pilar Flex基台的MT种植体，加载32牛/平方厘米；B组使用18颗带有定位（IN）Pilar Flex基台的MT种植体，加载20牛/平方厘米。基台根据ISO标准14801/2007进行测试。标本安装在与轴线成30°角的位置，承受133牛的负载、4赫兹的频率和1,000,000次循环。试验完成后，由电子扭矩计提供反向扭矩。数据采用独立样本t检验和配对t检验进行统计分析。显著性水平设定为<0.05。
获得的结果表明，定位Pilar Flex基台的扭矩损失占初始扭矩的百分比为49%，而NI Pilar Flex基台损失了14%。配对学生t检验显示，对于NI（<0.001）和定位（<0.001）基台，反向扭矩值均显著低于初始扭矩时施加的值。
根据所采用的方法，在单单位种植体假体中，NI Pilar Flex基台在反向扭矩方面比定位Pilar Flex基台更有效。在反向扭矩测试中，定位Pilar Flex基台的固位螺钉松动更明显，并且Pilar Flex基台未能显示出与冷焊接效果相关的良好结果。
