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The alveolar process (〔''OED'' 2nd edition, 1989 as .〕〔(Entry "alveolar" ) in ''(Merriam-Webster Online Dictionary )''〕) (alveolar bone) is the thickened ridge of bone that contains the tooth sockets (dental alveoli) on bones that hold teeth. In humans, the tooth-bearing bones are the maxillae and the mandible.〔Ten Cate's Oral Histology, Nanci, Elsevier, 2013, page 219〕 ==Structure== On the maxillae, the alveolar process is a ridge on the inferior surface, and on the mandible it is a ridge on the superior surface. It makes up the thickest part of the maxillae. The alveolar process contains a region of compact bone adjacent to the periodontal ligament (PDL), which is called the lamina dura when viewed on radiographs. It is this part which is attached to the cementum of the roots by the periodontal ligament. It is uniformly radiopaque (or lighter). Integrity of the lamina dura is important when studying radiographs for pathological lesions. The alveolar bone or process is divided into the alveolar bone proper and the supporting alveolar bone. Microscopically, both the alveolar bone proper and the supporting alveolar bone have the same components: fibers, cells, intercellular substances, nerves, blood vessels, and lymphatics. The alveolar bone proper is the lining of the tooth socket or alveolus (plural, alveoli). Although the alveolar bone proper is composed of compact bone, it may be called the cribriform plate because it contains numerous holes where Volkmann canals pass from the alveolar bone into the PDL. The alveolar bone proper is also called bundle bone because Sharpey fibers, a part of the fibers of the PDL, are inserted here. Similar to those of the cemental surface, Sharpey fibers in alveolar bone proper are each inserted at 90 degrees, or at a right angle, but are fewer in number, although thicker in diameter than those present in cementum. As in cellular cementum, Sharpey fibers in bone are generally mineralized only partially at their periphery. The alveolar crest is the most cervical rim of the alveolar bone proper. In a healthy situation, the alveolar crest is slightly apical to the cementoenamel junction (CEJ) by approximately 1.5 to 2 mm.〔 The alveolar crests of neighboring teeth are also uniform in height along the jaw in healthy situation.〔 The supporting alveolar bone consists of both cortical bone and trabecular bone. The cortical bone, or cortical plates, consists of plates of compact bone on the facial and lingual surfaces of the alveolar bone. These cortical plates are usually about 1.5 to 3 mm thick over posterior teeth, but the thickness is highly variable around anterior teeth.〔 The trabecular bone consists of cancellous bone that is located between the alveolar bone proper and the plates of cortical bone. The alveolar bone between two neighboring teeth is the interdental septum (or interdental bone).〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Alveolar process」の詳細全文を読む スポンサード リンク
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