Biomechanical Finite Element Analysis of Short and Long Implants In The Resorbed Maxillary Posterior Region

Background This aim of this study is to analyze different implant treatment concepts in the maxillary posterior region. The effects of using short or long implants, with or without bone graft, are investigated in terms of strength and integrity. Methods Three different 3D models were generated from a CBCT scan: short implant (SI), long implant after sinus lifting with graft (LISG) and long implant after sinus lifting without graft (LIS). After the necessary implant parts were integrated, the models were analyzed via finite element method (FEM). The resultant stress values in the cortical and cancellous bones are evaluated by applying vertical and oblique forces. The integrity and stability of plant parts have also been investigated. The treatment concepts are compared on the basis of the FEA results. Results FEA demonstrated that short implants resulted in greater stress concentrations within the peri-implant bone than long implants did. The maximum principal stress values in cortical bone were 100 MPa (tensile) and 133 MPa (compressive), whereas those in cancellous bone were 14 MPa (tensile) and 16 MPa (compressive), all of which are within physiological limits. Compared with short implants, long implants, with or without grafts, significantly reduced stress levels. There were significant reductions in both compression and tensile stresses in long implants. The stress distribution patterns indicated that oblique loading led to increased palatal stress concentration. Conclusions Although the stresses occurring in the short implant concept are greater under both masticatory loading conditions, the results obtained for both the short and long implant concepts remain within physiological limits where the bone can maintain its continuity without deformation. Trial registration Clinical trial number: Not applicable.