5. Jawbone's indexes changes after treatment of class II division 1 malocclusion with four premolar extraction

Vo Thi Thuy Hong, Do Le Phuong Thao, Nguyen Thi Thu Phuong

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Abstract

This study determined the change of the jawbone's indexes in the anterior-posterior, and vertical dimensions on Cephalometrics of class II division 1 malocclusion patients with extraction of four premolars. After treatment, SNA angle decreased by 0.15 ± 2.26o and the SNB angle increased by 0.15 ± 1.56o but there was no statistical significance. The indexes GoGn-SN, N-Me changed less than 1o, 1mm with no statistical significance. Thus, on analysis of Cephalometrics film, there was no change of the anterior-posterior and vertical dimensions of the maxillary and mandibular bones of the class II devision 1 malocclusion patients with extraction of four premolars.

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References

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