Comparative Microstrain Study of Internal Hexagon and Plateau Design of Short Implants Under Vertical Loading.

ABSTRACT

PURPOSE: To quantify microstrain development during axial loading using strain gauge analysis for short implants, varying the type of fixture-abutment joint and thread design. MATERIALS AND METHODS: An internal hexagon implant (4 × 8 mm) and a plateau design implant (4 × 8 mm) were embedded on the center of 10 polyurethane blocks with dimensions of 190 × 30 × 12 mm. The respective abutments were screwed onto the implants. Four strain gauges (SGs) were bonded onto the surface of each block, and 4 vertical SGs were bonded onto the side of each block. Axial load of 30 kgf was applied for 10 seconds in the center of each implant. RESULTS: The data were analyzed statistically by analysis of variance for repeated measures and Tukey test (P < 0.05). The interaction between implant and region factors have been statistically significant (P = 0.0259). Tukey test revealed a difference on plateau's horizontal region. The cervical region presented higher microstrain values, when compared with the medium and apical regions of the implants. CONCLUSION: Within the purpose of the study, the type of fixture-abutment joint is a relevant factor to affect the amount of stress/strain in bone simulation. The microstrain development was concentrated on the cervical region of the implant.