Material and methods. Under the conditions of a three-dimensional mathematical model of the lateral section of the lower jaw with three missing teeth, the stress-strain state of the defect replacement options was studied: three implants with covering crowns, a bridge prosthesis supported by two implants, a bridge prosthesis supported by a tooth and an implant. A load of 150 N was applied to the middle of the prosthetic structure in the vertical and inclined directions; the maximum stress values and their distribution were compared. The results of the study. The negative effect of the inclined load on the magnitude and distribution of stresses was confirmed (471.7 MPa versus 90.7 MPa with vertical load on the example of three implants), the most loaded zones of prosthetic structures were identified – the edge of the artificial crown and the implant junction zone. A uniform distribution of stresses from the bridge prosthesis to 2 support implants and a decrease in stress values were found when replacing the structure of three implants with crowns with a bridge prosthesis (16.1 MPa and 160.0 MPa). On the contrary, the overload of the support implant was recorded when replacing the second support implant with a tooth (1053.5 MPa with an inclined load). Conclusion. In comparison with three implants replacing a dentition defect due to the absence of three teeth, a bridge prosthesis supported by two implants reduces stresses in the implants and the covering structure. Replacing one support implant with a tooth increases the stresses in the structure on the implant to the strength limits of the titanium alloy in the abutment.