The study of angulation and position of third molars in premolar extracted orthodontic cases in Chinese population

摘要

The purpose of this study was to determine the relationship betweenthe inclinations of the second and third molars in patient treatedorthodontically both with and without extractions of premolars during aperiod of 2-2.5 years.
　　Angles were measured between the long axis of the 3rd molars andocclusal plane and between the long axis of 3rd molars and long axis of the2nd molar.
　　The variations in third molar angulations from pre treatment and posttreatments were compared using the Mann-Whitney U-test(＜0.05).
　　The purpose of this study was to determine the final position ofmandibular and maxillary third molars in patients treated orthodonticallyby methods of extractions and non extractions of premolars.
　　ObjectiveMy objective of this research is to confirm whether is beneficial forthe clinical orthodontist to extract the premolars in mild and severecrowding cases in order to gain space to accommodate for the correcteruption of the third molars in both upper and lower arches.

目录

声明

Content

ABSTRACT

Introduction

1 Materials and methods

1．1 Materials

1．1 methods

2 RESULTS

3 Discussion

4 Conclusion

reference

Acknowledgement