Biomechanical Analysis of Grafted and Nongrafted Maxillary Sinus Augmentation in the Atrophic Posterior Maxilla with Three-Dimensional Finite Element Method

This study is aimed at determining the optimal sinus augmentation approach considering the poor bone condition in the zone ofatrophic posterior maxilla. A series of simplified maxillary segment models varying in residual bone height (RBH) and bone qualitywere established. A 10 mm standard implant combined with two types of maxillary sinus augmentation methods was applied withthe RBH, which was less than 10 mm in the maxilla. The maximal equivalent von Mises (EQV) stress in residual bone wasevaluated. Bone quality had an enormous impact on the stress magnitude of supporting bone. Applying sinus augmentationcombined with grafts was suitable for stress distribution, and high-stiffness graft performed better than low-stiffness one. For7 mm and 5 mm atrophic maxilla, nongrafted maxillary sinus augmentation was feasible in D3 bone. Poor bone quality was anegative factor for the implant in the region of atrophic posterior maxilla, which could be improved by grafts. Meanwhile, thechoice of maxillary sinus augmentation approaches should be determined by the RBH and quality