Objective To explore the effect of maxillary sinus lift via transalveolar ridge approach in patients with maxillary posterior tooth loss. Methods A total of 88 patients with maxillary posterior tooth loss admitted to the Department of Stomatology, Xingping 145 Hospital from January 2021 to December 2023 were selected as the research subjects. According to the different treatment methods, they were divided into control group and observation group, with 44 patients in each group. The control group was given conventional clinical implant restoration surgery, and the observation group was given maxillary sinus lift via transalveolar ridge approach. The clinical efficacy, complications, oral function score and periodontal indexes were compared between the two groups. Results The total clinical effective rate of the observation group was 97.73%, which was higher than 81.82% of the control group (P <0.05). The incidence of complications in the observation group was lower than that in the control group (P <0.05). The scores of daily activities, language function and masticatory function in the two groups after 1 month of surgery were better than those before surgery, and those in the observation group were better than those in the control group (P <0.05). The probing depth and probing bleeding index in the two groups after 1 month of surgery were better than those before surgery, and those in the observation group were better than those in the control group (P <0.05). Conclusion Maxillary sinus lift via transalveolar ridge approach can improve the surgical efficiency of patients with maxillary posterior tooth loss, reduce the incidence of complications, and improve oral function and periodontal health.