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[A study on the lingual shape and position of the teeth in Chinese with normal occlusion]
1Department of Orthodontics, Peking University School of Stomatology, Beijing 100081, China.
Objective:
To measure the lingual surfaces of the teeth in normal occlusion and obtain the data for lingual brackets' bonding and modifying for Chinese.
Methods:
50 casts of nonorthodontic subjects with ideal occlusion were examined using the YM-2115 3D measurement instrument. The data was calculated by the relevant software and analysed statistically.
Results:
The reference values of the lingual surfaces of the teeth in normal occlusion were obtained. These include crown angulation(tip), crown inclination(torque), offset angles of molars and crown facial prominence.
Conclusions:
Compared with the data of foreigners, the characteristics of the lingual surface of the teeth in Chinese normal occlusion has many differences. The accurate placement of the lingual orthodontic brackets should be assisted by laboratory techniques because of the highly variable morphology of the lingual surfaces of the teeth.
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