RESUMEN
<p><b>OBJECTIVE</b>To study the influence of different shape of lower jaw on stress distribution at bone interface in the mandibular molar region of implant restoration models.</p><p><b>METHODS</b>Six models with different lower jaw shapes were constructed by using three-dimensional finite element method. Implant-bone interface stresses in these models were studied under vertical and lateral loads.</p><p><b>RESULTS</b>No matter in the condition of vertical loading of lateral loading, stress distribution patterns were similar in variant models and differences of stress values were not statistically significant. The maximal differences in Von-Mises stress, compressive stress and tensile stress among the six models were 6.4%, 2.8% and 6.2%respectively.</p><p><b>CONCLUSION</b>It is rational to simplify the lower jaw shape in finite element analysis.</p>