Relevance Long-term results of orthopedic rehabilitation of patients with partial and complete absence of teeth using implants show a certain number of failures and complications. The most studied cause of implant removals and the development of periimplant chronic inflammation is the activity of periodontopathogenic microflora due to poor oral hygiene.
To a much lesser extent, the influence of biomechanical risk factors on the effectiveness of prosthetics on implants in the long term is known. In particular, there is insufficient information about the occurrence of adverse biomechanical factors in individuals with dental implants
The purpose of the study: to analyze the frequency of detection of unfavorable biomechanical conditions for the functioning of prostheses on implants.
Material and method Based on the results of clinical and X-ray examination of 417 patients (1222 intraosseous implants) who completed fixed prosthetics with partial absence of teeth 10 years ago, differentiation of biomechanical conditions for the functioning of implants was carried out. The following conditions were diagnosed: density, volume of bone tissue; presence of previous bone grafting; thickness of the cortical bone; length and diameter of the implant; characteristics of the junction with the abutment; position of the implant relative to the alveolar ridge; the ratio of implants and prosthetic units in fixed prostheses; the presence of occlusive supracontacts on implants; the degree of replacement of dentition defects; the presence of approximal contacts; association with teeth; type of load.
Results. Thin cortical bone, as an inadequate biomechanical condition, was found in 65.7% of implants; low bone density in 32.3%, insufficient and uncompensated bone volume in 15.5%. The possibility of overload of implants due to the absence of approximal contacts with adjacent teeth or prostheses was detected in 60.3% of implants, occlusive supracontacts in 58.4%, installation of narrow and short implants (respectively 29.1% and 15.5% of implants), installation of implants with a slope (33.1%). Incomplete replacement of the dentition defect and, as a consequence, increased functional load were found in 57.3% and 28.1% of implants, respectively; an insufficient number of support implants spread to 21.5%. The combination of implants with teeth with a bridge prosthesis was typical for 19.2%.
Conclusion. In modern conditions of the organization of implantology, the qualification of doctors and the motivation of patients to the ideal volume of prosthetics on implants, the functioning of fixed prostheses on intraosseous implants often occurs in inadequate biomechanical conditions