目的: 研究C57BL/6小鼠牙齿的解剖特点.方法: 显微CT对16只C57BL/6小鼠的颅颌标本进行扫描及三维重建,观测牙齿内、外部的解剖结构.结果: 小鼠上切牙比下切牙平均弯曲半径更小(2. 37 mm比6. 31 mm),长度更短(8. 63 mm比11. 19 mm).上颌第二磨牙(三根) 腭根、下颌第一磨牙(双根) 远中根及下颌第二磨牙双根均为1-2型根管,其余牙根为单根管.磨牙近远中径、牙尖及发育沟数随前后牙位逐次减小.牙髓腔形态与牙体外形相似.结论: C57BL/6小鼠具有强壮的切牙,第一、二、三磨牙大小及解剖复杂程度逐次减小,反映了一种退化的趋势.%Objective: To investigate the dental anatomy of C57BL/6 mice strain. Methods: The skulls and alveolar bones of 16 C57BL/6 mice were scanned by a micro-CT scanner. After 3D reconstruction,the internal and external anatomy of each tooth type was examined. Results: The upper incisors were more curved (mean radius: 2. 37 mm vs. 6. 31 mm) and shorter (mean tooth length: 8. 63 mm vs. 11. 19 mm) than the lower incisors. The palatal roots of the upper 2nd molars (3-rooted),the mesial roots of the lower first molars(double-rooted) and the mesial and distal roots of the lower 2nd molars (double-rooted) had type 1-2 canal form,and all the other roots had a single canal. The mesiodistal diameter of the crown,as well as the numbers of the cusps and developing grooves decreased from the 1st to the 3rd molars. The external tooth shape was very similar as the morphology of the pulp cavity. Conclusion: The C57BL/6 mouse have strong incisors. The tooth size and the anatomic complexity decrease from the 1st to the 3rd molars,which reflects a trend of degradation.
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