（精）口腔医学英语讲义.ppt

The Development and Component of a Tooth 吴堪葵 广州医学院第二附属医院 The Development and Component of a Tooth Component of a Tooth Enamel Millions of rods/prisms 釉柱 Enamel rods From enamel-dentinal junction 釉牙本质界 To tooth surface Enamel rods Composed of apatite crystals 磷灰石晶体 Mainly hydroxyapatite 羟基磷灰石 Rod sheath 釉柱鞘 Controversial 有争议的 Higher content of organic material 有机物 Different crystal orientation 晶体排列方向 Dentinal tubules From pulp To enamel-dentinal junction 釉牙本质界 Wide in the pulp side Narrow in the enamel side Similar to bone difference No vascularity(血管 ) Contain cementocytes（成牙骨质细胞） Pulp Odontoblast 成牙本质细胞 位于牙髓周围，呈柱状紧接前期牙本质排列成一层 主要功能：形成牙本质 小结 Each tooth has four main parts, including the following: enamel - the outer layer of the tooth. dentin - the inner layer and the main part of the tooth. cementum- only found on the underside of the tooth. pulp - part of the inside of the tooth that contains the nerve and other delicate tissue. A tooth and its surroundings Periodontium 牙周组织Maintain a tooth in its functional position 支持牙的功能 Gingiva 牙龈 Mucosa which surrounds the teeth Free gingiva 游离龈 Attached gingiva 附着龈 Interdental papilla 龈乳头 牙龈上皮gingival epithelium 龈沟上皮salcular epithelium 结合上皮junctional epithelium 龈谷上皮 固有层: 胶原纤维 神经、血管 Free gingiva 游离龈 Terminal edge of gingiva 牙龈边缘 Surrounds the tooth in collar fashion Forms the soft tissue wall of the gingival sulcus 龈沟（0.5-3mm 平均1.8mm) Attached gingiva 附着龈 Continuous with the free gingiva By a shallow linear depression, the free gingiva groove 游离龈沟 Tightly bound (紧密附着)to the underlying periosteum of alveolar bone(牙槽骨骨膜) Surface stippling 点彩: increase abrasive resistance 增强对机械摩擦的抵抗 Interdental gingiva Occupies the interproximal space beneath area of teeth contact 牙间隙 Pyramidal (锥) or col (谷)shape Periodontal ligament 牙周韧带 Also called periodontal membrane牙周膜 Locates between alveolar bone and the root Supportive 支持功能 主要纤维一端埋入牙骨质，一端埋入牙槽骨 将牙固定在牙槽窝中 组成：纤维、基质、细胞、血管 Periodontal li