关键词: 早期矫治, 横向不调, 扩弓

Abstract:

The sagittal discrepancy in children which undermines esthetics to a great extent is frequently noticed by parents and is the major reason for patients to seek treatment. Transverse discrepancy，however，is more prone to be overlooked by orthodontists due to the overemphasis of diagnosis and treatment of the sagittal discrepancy. Furthermore，the discrepancies in all three dimensions of space are highly correlated and reciprocally reinforced. Therefore the transverse discrepancy should not be neglected owing to its potential of worsening the discrepancies in other dimensions. Comprehensive evaluation and accurate diagnosis of transverse discrepancy along with all other discrepancies by using postero-anterior cephalogram，plaster cast and cone-beam computerized tomography（CBCT）is positively contributed to getting esthetic and stable treatment results. Besides，a beautiful smile is always compromised by a narrow dental arch，but a full smile，which can be readily achieved by arch expansion，is always what patients are looking for and what orthodontists are working hard to get. Early treatment with maxillary expansion is able to not only improve smile esthetics of children but also lower the treatment complexity and enhance the effectiveness of the second phase orthodontic treatment.

Key words: early treatment in orthodontics, transverse discrepancy, maxillary expansion