Objective To evaluate the application value of different methods in reducing the thickness of the occlusal muscle by comparing the changes in the thickness of the occlusal muscle after three methods of treatment. Methods Five patients underwent simple mandibular osteotomy, four patients underwent mandibular osteotomy + partial bite resection, and four patients underwent mandibular osteotomy + botulinum toxin type A injection into the bite muscle. The average reduction of occlusal muscle thickness at 12 weeks after surgery was (4. 876 ± 5. 270) %, (32. 939 ± 2. 900) %, (14. 006 ± 4. 866) % in the mandibular osteotomy alone, mandibular osteotomy + partial excision of the occlusal muscle, and mandibular osteotomy + botulinum toxin type A injection groups, respectively, and (2. 637 ± 4. 806) %, (30. 286 ± 3. 644) % at 24 weeks after surgery. (30. 286 ±3. 644)% , (36. 878 ±4. 702)%, respectively, at 24 weeks after surgery. Conclusion In terms of long-term results, mandibular osteotomy combined with botulinum toxin type A injection into the bite muscle was more effective in reducing the thickness of the bite muscle compared with mandibular osteotomy combined with partial excision of the bite muscle or mandibular osteotomy alone. Upper