Objective To analyze the effect of fixed denture restoration on oral health in patients with severe tooth abrasion and dentition defect. Methods A total of 80 patients with severe tooth abrasion and dentition defect admitted to our hospital from May 2022 to May 2023 were selected as the research subjects. They were divided into the control group and the observation group, with 40 patients in each group. The control group was treated with occlusal pad removable partial denture restoration by the random number table method, and the observation group was treated with fixed dental denture restoration. The restoration effect, oral health impact degree, aesthetic satisfaction, comfort and adverse event rate were compared between the two groups. Results The scores of marginal coloring, marginal fit, aesthetics and morphological color in the observation group were all higher than those in the control group (P <0.05). The scores of functional limitation, pain and discomfort, physical and mental defects and ability limitation in the observation group were all lower than those in the control group (P <0.05). The scores of aesthetic satisfaction and comfort in the observation group were higher than those in the control group (P <0.05). The incidence of adverse events in the observation group (17.50%) was lower than that in the control group (55.00%) (P <0.05). Conclusion Fixed denture restoration can effectively improve the restoration effect and oral health, at the same time, it can improve the aesthetic satisfaction of patients and reduce the incidence of adverse events.