Dental implant-supported fixed restorations provide the best masticatory rehabilitation comparing to conventional removable prosthodontic treatment. Nevertheless, the issue of the rational restoration structure design is still open, especially in low-cost military dentistry where expensive technologies are limited in use due to limited financial support. The critical case of functionally important two molars loss treatment was considered in atrophic maxilla with types III and IV bone, when implantation is intricate due to insufficient bone height, low bone density, thin cortical bone. In such challenging conditions, placement of implant-supported cantilever crown was proposed as a reasonable approach. Modelling of osseointegrated bone-implant interface according to Frost Mechanostat theory principles was carried out to evaluate the treatment perspective. Four implants of different length and diameter used as support for restoration, were studied. Wide spectrum of human bone elasticity parameters was analyzed in order to generalize the results of the study to wide group of patients. When placed in type III bone, the studied implants induced physiologically acceptable strains in adjacent bone. In type IV bone, 4.5 × 5.0 mm implant caused bone overstrain resulted in following implant loss. 6.0 × 5.0 mm and 4.5 × 8.0 mm implants were unsuitable when cortical bone was extremely soft, i.e. its elasticity modulus was less than 4 GPa. So, only the 6.0 × 8.0 mm implant was recognized as reliable option to achieve the success of implant-supported cantilever crown in type IV bone. These results should be taken into account by clinicians when short implants are planned as the supports of cantilever crowns in compromised maxilla.