In vitro analysis of the influence of surface treatment of dental implants on primary stability

Surface treatment interferes with the primary stability of dental implants because it promotes a chemical and micromorphological change on the surface and thus stimulates osseointegration. This study aimed to evaluate the effects of different surface treatments on primary stability by analyzing insertion torque (IT) and pullout force (PF). Eight samples of implants with different surface treatments (TS - external hexagon with acid surface treatment; and MS - external hexagon, machined surface), all 3.75 mm in diameter x 11.5 mm in length, were inserted into segments of artificial bones. The IT of each sample was measured by an electronic torquemeter, and then the pullout test was done with a universal testing machine. The results were subjected to ANOVA (p < 0.05), followed by Tukey's test (p < 0.05). The IT results showed no statistically significant difference, since the sizes of the implants used were very similar, and the bone used was not highly resistant. The PF values (N) were, respectively, TS = 403.75 +/- 189.80 and MS = 276.38 +/- 110.05. The implants were shown to be different in terms of the variables of maximum force (F = 4.401, p = 0.0120), elasticity in maximum flexion (F = 3.672, p = 0.024), and relative stiffness (F = 4.60, p = 0.01). In this study, external hexagonal implants with acid surface treatment showed the highest values of pullout strength and better stability, which provide greater indication for their use.National Council for Scientific and Technological Development [149531/2010-9]National Council for Scientific and Technological Developmen

Analysis of the surface deformation of dental implants submitted to pullout and insertion test

Objective: The aim of the present study was to evaluate the possible deformations in the surface of dental implants submitted to pullout and insertion test in polyurethane synthetic bone, using scanning electron microscopy. Material and Methods: Four different types of implants were used: Master Screw, Master Porous, Master Conect AR and Master Conect Conical (n = 8). These implants were into the femoral head synthetic bone (Synbone) and removed through the pullout test, performed with a universal testing machine (EMIC MEM 2000). All the screws, before and after the mechanical tests, were micro structurally analyzed in a Scanning Electron Microscope (SEM - Zeiss EVO50), utilizing a magnification of 35 times. The results were subjected to ANOVA and Tukey tests (α =0.05). Results: Only the Master Conect Conical and Master Porous implants presented statistically significant difference to pullout and maximum deformation (P = 0.014 and P = 0.009, respectively). The SEM images did not show morphological changes of the implants when compared before and after the mechanical tests. Conclusion: We concluded that Master Porous presented higher pullout resistance, suggesting a greater primary stability