关键词: 牙周系统治疗, 正畸治疗, 微翻瓣牙槽嵴保存术, 种植治疗

Abstract: Periodontitis is one of the common oral diseases. Severe periodontitis may lead to tooth loosening，displacement，or even loss，seriously affecting patients′    oral health and quality of life. If severe periodontitis combines with malocclusion，the treatment period will be longer and the process will be more complicated. Multidisciplinary treatment is required for these cases. The treatment goals for these patients are not only to regain periodontal health，but also to restore complete dentition，reconstruct occlusal function，and improve esthetics. This article demonstrates the multidisciplinary treatment for a patient with generalized stage Ⅳ Class C periodontitis combined with anterior crossbite，including initial periodontal therapy，orthodontic treatment，micro crestal flap-alveolar ridge preservation，and dental implant therapy，which has achieved satisfactory results for both the patient and doctors and improved the patient′s oral function and esthetics. This case provides experience for the multidisciplinary treatment of complex clinical situations.

Key words: systemic periodontal therapy, orthodontic treatment, micro crestal flap-alveolar ridge preservation, dental implant therapy