This is a problem that has plagued everyone for a long time. The root cause is still the lack of prospective, large sample clinical statistics. The bite muscle is a strong, thick, rectangular muscle that starts at the zygomatic arch and ends outside the mandibular branch and at the angle of the jaw. It is divided into superficial (S), middle (M) and deep (D) layers. When you bite hard, the hard part on both sides of the cheeks is the bite muscle. The average thickness of the bite muscle in national females is 12.3mm (average of 504 cases tested by ultrasound). Therefore, the bite muscle is mildly developed, i.e. <10mm in thickness; moderate: 10-13.9mm, and severe >14mm. Currently, the main reported ways to “slim down” the bite muscle are: 1, Botulinum toxin type A injection 2, partial bite muscle excision 3, radiofrequency ablation 4, hormone injection, such as tretinoin. 5, others, such as partial atrophy of the bite muscle after jaw angle osteotomy For safety reasons, the majority of doctors currently prefer Botox injections. The safe area for botulinum toxin injection is the line between the earlobe and the corner of the mouth (upper boundary), otherwise it is easy to cause local depression, which is unsightly. The rest of the boundaries are the bite muscle area. The current injection methods for the bite muscle are generally: two-point method, three-point method, and five-point method. An interesting topic: whether multiple botulinum toxin injections will last, and listen to the analysis of the PRS treatise: Cases: 121 patients with botulinum toxin (Dysport, 1/3 the effectiveness of BOTOX) injected into the bite muscle, average age 27.3 years. 28 cases received 3 injections, 41 cases received 4 injections, 23 cases received 5 injections, 16 cases received 6 injections, 6 cases received 7 injections, and 1 case received 8 injections. One case received 8 injections. Method: Before each injection, the thickness of the occlusal muscle was measured by ultrasound, which is the most prominent point below the line connecting the earlobe and the corner of the mouth. The intersection of the line of the earlobe + corner of the mouth and the line of the external canthus + angle of the mandible could also be chosen. The dose of each injection is determined by the thickness of the bite muscle. The interval between each injection is from 5 months, gradually decreasing to 10 months. The thickness of the bite muscle also decreases sequentially. It is important to emphasize that the interval between each follow-up was more than 6 months, so that the “rebound” factor could be partially excluded. Results: The thickness of the occlusal muscle decreased from 13.32 mm to 9.94 mm, and there was no significant difference in the thickness of the occlusal muscle between the age groups. Conclusion: Regular, regular, ultrasound-detected bite muscle injections resulted in a sustained, progressive reduction in bite muscle thickness and a sustained reduction in the amount of botulinum toxin used. The degree of “recurrence” was not high.