The effect of cuspal inclination on stress distribution and implant displacement in different bone qualities for a single tooth implant: A finite element study

Abstract

Background: The aim of the present finite element study was to analyze effect of cuspal inclination on stress distribution and implant displacement in different bone densities for a single tooth implant. Materials and Methods: A three dimensional finite element model of mandibular molar section of the D1 bone (entirely cortical) and D4 bone (1 mm cortical shell with low density trabecular core) to receive an implant was constructed. Three ceramic crowns with cusp inclinations of 0 degree, 10 degree and 30 degree were modeled. A mechanical load of 202.23 N was applied at three different regions; the central fossa and 1- and 2-mm offsets horizontally from the center to the buccal side for the varying inclinations. The finite element analysis was performed and stress levels using von Mises stresses and maximum displacement (in mm) were calculated. Results: The maximum stress concentration in cortical bone was seen around the neck of the implant. There was favorable distribution of stresses during loading at the central fossa with maximum stress being 15.10 Mpa for 0 degree, which increased to 54.09 Mpa for 10 degree and 86.19 Mpa for 30 degree inclination at 2 mm offset. Higher stresses were generated in D4 than D1 bone density under all loading conditions. Conclusion: The occlusal topography plays an important role in stress distribution and may be helpful in preventing crestal bone loss. This phenomenon is more pronounced in poor quality bone. Therefore, proper occlusal morphology becomes a critical issue in poor quality bone for implant longevity.