Objective To investigate the effect of oral implant supported denture on oral function and periodontal indexes in patients with dentition defect. Methods A total of 60 patients with dentition defect admitted to Nanning Angel Dental Zhen’ai Dental Clinic from January 2021 to December 2023 were selected and divided into the control group (30 patients) and the observation group (30 patients) according to different treatment plans. The control group received fixed denture restoration, and the observation group received oral implant supported denture. The repair effect, oral function, periodontal indexes and alveolar ridge resorption were compared between the two groups. Results The total effective rate of repair in the observation group (93.33%) was higher than that in the control group (73.33%) (P <0.05). After treatment, the scores of language function, retention function, aesthetic function and masticatory function in the two groups were higher than those before treatment, and those in the observation group was higher than those in the control group (P <0.05). The gingival index, plaque index, and sulcus bleeding index in the observation group were lower than those in the control group (P <0.05). The degree of alveolar ridge resorption in the observation group was lower than that in the control group (P <0.05). Conclusion The implementation of oral implant supported denture is conducive to the recovery of oral function, and has good aesthetics, which is beneficial to maintaining periodontal health in patients.