The aim of this study was to evaluate implants survival rate, marginal bone loss, surgical and prosthetic complications of implants placed through sinus floor elevation and tilted implants en-gaged in basal bone in order to bypass maxillary sinus. 60 patients were enrolled for this study. According with residual bone height of posterior maxilla the sample was divided in three groups of 20 patients: Group A (lateral sinus floor elevation), Group B (transrectal sinus floor elevation) and Group C (tilted implants employed to bypass sinus floor). Follow-up visits were performed one week after surgery, at 3, 6 months and then once a year for next 4 years. The outcomes were implants survival rate, marginal bone loss and surgical and prosthetic complications. Although the Group A, B and C have demonstrated an implants survival rate of 83.3%, 86,7% and 98,3% respectively, the statistically analysis showed that there was no statistically significant difference between groups. Statistically significant differences between the groups were also not found con-cerning marginal bone loss, as recorded by intra-oral X-ray measurements during follow-up. About complications it wasn’t possible to perform a statistical analysis. To as to reduce potential surgical risks implants placement in basal bone should be preferred.