Renato Nishioka
Abstract:
The present study was designed to analyzed the strain distribution caused by varying the implant-abutment joint (morse taper, internal and external hexagon) and implant alignment.The hypothesis of this study suggests that different connections promote different microstrain, and the off set arrangement of 3 implants may be preferred over the straight-line placement.
To simulate clinical conditions a real-life arrangement of three external, internal hexagon and morse taper implants labeled mesially, distally as A, B, and C (AS Technology titaniumfix, São José dos Campos, São Paulo, Brasil) were arranged in the middle of six measurement models 70 x 40 x 30mm3 polyurethane rectangular blocks. Four Strain gauges (SG) were bonded on the surface of polyurethane block and it was designated SG1 placed mesially adjacent to implant A, SG2 and SG3 were placed mesially and distally adjacent to the implant B and SG4 was placed distally adjacent to the implant C. The thirty superstructure's occlusal screws were tightened onto the Microunit abutments (AS Technology titaniumfix, São José dos Campos, São Paulo, Brasil) with a torque of 10 N cm using the manufacture's manual torque-controlling device.
There were statistically significant differences in prosthetic connection (P-value = .0074<0.5). There were not statistically significant differences in placement configuration (P-value =.7812>0.5).