Abstract: Lateral sinus floor elevation is an effective treatment method to increase the bone height of posterior maxillary alveolar ridge, whose success depends on the formation of new bone and the long-term survival rate of implants. There are many factors affecting the formation of new bone and the survival rate of implants after the lateral sinus floor elevation, such as the height of remaining alveolar bone, the size of bone window, the coverage of bone window, and the way of bone grafting. Some scholars have considered that reducing the size of bone window can preserve more residual bone, while covering the biological barrier membrane or replaceable bony window can prevent the invasion of soft tissue, which has a positive effect on the formation of new bone and the survival rate of implant. Some scholars have proposed that adult stem cells with differentiation potential, using growth factor to replace autologous bone and other bone replacement materials should be combined to promote the formation of new bone. Some scholars have proposed that during simultaneous implantation, the reduction of residual alveolar bone height or without grafting would not affect the formation of new bone and the survival rate of implants, so as to expand the indication range of lateral sinus floor elevation. This paper tries to discuss these related factors.

Key words: maxillary sinus augmentation, lateral window, new bone formation, survival rate