Stress Distribution on Short Implants with Varying Crown Heights - An In vitro Study

The aim of this study is to determine the stress in short implants loaded with varying crown heights using a 3D finite element analysis. A total of three mandibular sectional bone blocks depicting the mandibular left first molar region were modeled. Each block carried Bicon implants of the same size and was designated B1, B2, and B3. The implant- crown ratio is 1:1.5, 1:2.5, and 1:3 respectively. The loading protocol included axial and oblique loads. The von Misses' equivalent stresses at the implant-bone interface were evaluated. Intergroup comparison was determined using one-way ANOVA analysis, and P values were calculated. Under an axial load of 600N, the models B1, B2, and B3 do not show any statistically significant P-values at the crestal module of the implant, abutment, and bone, whereas in crowns, the P-values were highly significant. Under an oblique load of 225 N at 0°, 45°, and 90°, model B3 showed the highest values in the crestal module, abutment, and crown. Based on the intergroup comparison and P value the study concluded that the variance in the crown height does not affect the bone and therefore microfracture of the bone and failure of osseointergration is not likely.