Nicoleta Ioanid, N. Necu, V. Burlui
The complexity of the forces which act on the dental implant can have miscellaneous consequences on the periimplantar tissues. In this study we want to reveal the influence of two geometrical parameters, implant length and diameter, considered critical factors in achieving and maintaining osseointegration in optimal parameters. The analysis of the mechanical stress distribution over the implant bed was based on the finite element technique, using three-dimensional computerized models. The simulation was applied for cylindrical, solid and non-threaded implants made of titan. Three different lengths were chosen for the embedded endosseous implant, 8 mm, 10 mm. and 12 mm, all of them having the same diameter (3.75 mm.), respectively, three different diameters: 4 mm, 5 mm. and 6 mm, all of them having the same length (10 mm.). The implant with 8 mm length and 3.75 diameter (the smallest size used) produced not only a concentration of the strain on the cortical wall, but maximally values on the stressed area and a minimally strain dissipation on the bone adjacent to implant. When the length increase, maximally values decrease, being distribute on a smaller zone, and the residual stress dissipating on a larger area. The increases of the implant diameter significant reduce the strain on the bone adjacent to implant neck. This influence is more effective comparing with implant length, due to a more favorable distribution of the forces applied in our study. If the diameter increases with only 1 mm. it determines a significant strain reduction on the periimplantar bone, almost 50%, and may achieve till 60% (in case of more than 6 mm. diameter).