下颌牙根尖与下颌舌骨线的位置关系

<正> 参考文献认为:下颌切牙及尖牙的根尖位于下颌舌骨线以上;下颌磨牙的根尖位于下颌舌骨线以下,因此,当下颌牙根尖感染且穿破舌侧骨板时,前者可侵及舌下间隙,后者可导致颌下间隙感染。我们在教学实践中,认为上述解剖描述并不完全合乎实际情况,为此,对下颌牙根尖与下颌舌骨线的位置关系进行了观测。

The Relatjon between the Apices of the Roots of the Mandibular Teeth and the Mylohyoid lines

3141 Apices of the roots ot the mandibular teeth and their relation to the mylohyoid lines were studied. The results were outlined as follows: 1. The Apices of the roots of the mandibular teeth were situated above the mylohyoid lines, they were: (1) The incisors (in l00%),canines (in 100％) and the first premolars (in 100％) (2) The second prernolars (in 92. 13％). (3) The mesial roots (in 85％) and the distal roots (in 69.62％) of the first molar. (4) The mesial roots (in 33.58％) and the distal roots (in 24.45％ of the second molars. (5) The mesial roots (in 16.67％)and the distal roots (in 6.66％)of the third molars. 2. The Apices of the roots of the mandibular teeth were situated below the mylohyoid lines. They were: (1) The second premolars (in 6.41X). (2) The mesial roots (in 3.46％)and the distal roots (in 11.15％)of the first molars. (3) The mesial roots (in 31.02％)and the distal roots (in 42.34％)of the second molars. (4) The mesial roots (in 50％)and the distal roots (in 60.61％)of the third molars. 3. As stated above, according to the relations between the Apices of the roots of the mandibular teeth and the mylohyoid lines, the authors con- sider that lt is doubtful that lingual spread of dental infection in the mau- dibu lar premolars in the 1ate stages result in a sublnaxillary ce lulitis.