Objective To explore the effect of implant anchorage assisted maxillary skeletal expander (MSE) in the treatment of adult maxillary transverse dysplasia (MTD). Methods A total of 80 adult patients with MTD admitted to our hospital from March 2019 to January 2023 were randomly divided into control group and observation group, with 40 patients in each group. The control group was treated with stent fixed spiral expander, and the observation group was treated with implant anchorage assisted MSE. The clinical efficacy, maxillofacial structure index, upper airway structure index and complications were compared between the two groups. Results The total effective rate of treatment in the observation group was 97.50%, which was higher than 87.50% in the control group (P <0.05). The ANB and MP-SN angles of the two groups after 1 year of treatment were higher than those before treatment and after 6 months of treatment, and those of the observation group were higher than those of the control group (P <0.05). The U1-SN and L1-MP angles of the two groups after 1 year of treatment were lower than those before treatment and after 6 months of treatment, and those of the observation group were lower than those of the control group (P <0.05). After 3 months of treatment, SPL and OP-V in the two groups were lower than those before treatment, and those in the observation group were lower than those in the control group (P <0.05). After 3 months of treatment, OP-A in both groups was higher than that before treatment, and that in the observation group was higher than that in the control group (P <0.05). There was no significant difference in SPL, OP-V and OP-A between the two groups after 1 year of treatment (P >0.05). The incidence of complications in the observation group was 7.50%, which was lower than 20.00% in the control group (P <0.05). Conclusion Implant anchorage assisted MSE has a good effect in the treatment of adult MTD, which can effectively improve the upper airway and maxillofacial structure of patients, the risk of complications after treatment is low, and the application safety is high.