关键词: 上颌横向发育不足, 牙弓, 基骨, 治疗, 扩弓

Abstract: Transversal imbalance of the maxillary and mandibular is a common malocclusion in orthodontic treatment. Maxillary transverse deficiency is more common. Understanding the general pattern of the development of dental arch and basal bones′ width of maxillary and mandibula and mastering the treatment methods for its developmental abnormalities are important conditions for the correct implementation of treatment. This article provides a review on the general pattern of dental arch and basal bones′ transversal development of maxillary and mandibula，influencing factors and treatment methods of maxillary transverse deficiency，in order to provide reference for clinical diagnosis and treatment.

Key words: maxillary transversal deficiency, dental arch, basal bone, treatment, arch expansion