Objective To analyze the effect of orthodontic treatment combined with conventional repair in patients with malocclusions and dentition defect. Methods A total of 86 patients with malocclusions and dentition defect admitted to Gaotang County People's Hospital from January 2021 to January 2022 were selected and divided into reference group (n =60) and study group (n =26) according to the random number table method. The reference group was treated with routine repair, and the study group was treated with orthodontic treatment first and then with routine repair. The clinical effect, language function, masticatory function and cosmetic effect were compared between the two groups. Results The total effective rate of treatment in the study group was 100.00%, which was higher than 85.00% in the reference group (P <0.05). After treatment, the scores of language function and masticatory function in the study group were higher than those in the reference group (P <0.05). The scores of neat arrangement, complete coverage and normal occlusion in the study group were higher than those in the reference group (P <0.05). Conclusion Before routine repair, orthodontic treatment can improve the tooth morphology, masticatory function and language function of patients with malocclusions and dentition defect, and the aesthetics is high.