下颌骨内侧面副孔的观测及其临床意义

Measurement of accessory foramina on the medial mandibular surface and its clinical significance

目的 :观测下颌骨内侧面副孔的数量与分布 ,探讨其与肿瘤浸润的关系。方法 :将 74块下颌骨内侧面分为 2区 6部 ,在 1 0～ 2 0倍显微镜下观察各区、部的副孔数量及分布规律。结果 :副孔数量在不同的标本上相差很大 ,平均为 (78.7± 34 .4)个。上区的副孔数比下区的少 ,在上区 ,下颌切迹部副孔数量最多 ,其次为髁突部和冠突部 ;在下区 ,中部副孔数量最多 ,其次为上部和下部。在下颌孔的内侧面副孔的出现率最高 (99.3 % ) ,其次为两侧的颏结节 (72 .8% )、颏结节上方的正中孔 (68.9% )及二腹肌窝(66 .2 % )。结论 :副孔为肿瘤由骨皮质表面进入网状骨质提供了直接通路 。

Objective: To study the number and distribution of accessory foramina on the medical mandibular surface and the relationship between accessory foramina and tumor spread.Methods:This study involved 74 mandibles and each of them was divided into 2 regions and 6 sections.Under a magnification (×10～×20), the number and distribution of accessory foramina were observed in 2 regions and 6 sections.Results: The number of accessory foramina varied greatly from specimen to specimen.The superior region has fewer formina than the inferior region. In the superior region, the sigmoid section possessed the greatest proportion, followed by the condylar and the coronoid; in the inferior region, the middle third section possessed the greatest proportion, followed by the upper third section and the lower third section. The medial facing wall of the mandibular foramen was found to be the commonest dedicated sites (99.3%), followed by foramina on either of the genial ttubercles (72.8%), the median foramen above the genial tubercles (68.9%) and the digastric fossa (66.2%). Conclusions: Accessory foramina provide a direct path for tumor spread from the cortical surface to the cancellous bone, the occurrence of foramina on the medial facing wall of the mandibular foramen and other sites along the mandibular canal makes this area most vulnerable to tumor spread.