Journal of implantology and applied sciences ISSN:2765-7833(Print) 2765-7841(Online) 대한구강악안면임플란트학회지

Mathematical analyses were made to calculate the amount of forces transferred to each implant in cantilevered prostheses supported by Branemark implants. Modulus of Elasticity of bone and implant were ignored. No movement of implants in the bone was assumed. Principles of Newton’s first and third laws of mechanics by summing the forces and moments to zero were applied. Extreme rigidity of superstructure was assumed. Allowance of micromovement of the superstructure by elongation of gold screw is a crucial factor to transfer forces to other implants. The calculations showed that 1) highest compressive forces were concentrated on the most distal implant, 2) amounts of tensile forces on each implant were identical (250N) while bending moments increased proportionally to interimplant distant from the first implant, 3) No forces were transferred to cross arch implants under average magnitudes of occlusal forces at cantilever section, 4) interimplant distance rather than cantilever length is important to minimize overload, and 5) design of cantilever length to prevent screw loosening and/or fracture could be estimated clinically.