Objective. To substantiate the prevention of overload of periimplant bone tissue according to clinical studies and mathematical modeling. Materials and methods. A parallel study was conducted of the influence of inadequate biomechanical factors on the effectiveness of prosthetics on implants in 181 patients with a service life of 10 years, as well as on the parameters of the stress-strain state of periimplant bone tissue in three-dimensional mathematical modeling. Results. Against the background of average rates of periimplant inflammation and bone resorption detected 10 years after implant placement (55.2%), as well as the frequency of implant removal (11.4%), inadequate biomechanical factors of implant installation and operation increase the frequency of implant removal to 23.3%. Unfavorable biomechanical factors include the tilt of implants, narrow implants, and incompletely replaced dentition defects. The clinical data are consistent with the pattern of an increase in functional stresses in periimplant bone tissue under unfavorable biomechanical conditions according to three-dimensional mathematical modeling (up to five times with an inclined load). At the same time, stresses reach the limits of bone strength in situations such as peri-implantitis with bone resorption of more than a third of the implant length, implant tilt or the use of an abutment with an angle of 30°, the use of narrow implants, overload with incomplete replacement of the dentition. Conclusion. The negative impact of inadequate biomechanical conditions of the installation and operation of implants on the effectiveness of implantation has been established. Clinical data are consistent with the pattern of increasing functional stresses in the peri-implant bone tissue in unfavorable biomechanical conditions according to the data of three-dimensional mathematical modeling. In unfavorable load conditions, a fivefold increase in stresses in the cortical or spongy peri-implant bone tissue is possible, especially when the load vector deviates from the axis of the implant.
Olesova et al. (Thu,) studied this question.