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The palatine bone (〔''OED'' 2nd edition, 1989.〕〔(Entry "palatine" ) in ''(Merriam-Webster Online Dictionary )''.〕) is an irregular bone of the facial skeleton in many animal species. It is commonly termed, with the maxilla, the hard palate. (Palate is derived from Latin ''palatum'' which is unrelated to ''palatium'' 'palace', from which other senses of palatine derive). == Structure== The palatine bone is situated at the back part of the nasal cavity between the maxilla and the pterygoid process of the sphenoid bone. It contributes to the walls of three cavities: the floor and lateral wall of the nasal cavity, the roof of the mouth, and the floor of the orbit; it enters into the formation of two fossæ, the pterygopalatine and pterygoid fossæ; and one fissure, the inferior orbital fissure. The palatine bone somewhat resembles the letter L, and consists of a horizontal plate and a perpendicular plate and three outstanding processes—viz., the pyramidal process, which is directed backward and lateral from the junction of the two parts, and the orbital and sphenoidal process, which surmount the vertical part, and are separated by a deep notch, the sphenopalatine notch. The two plates form the posterior part of the hard palate and the floor of the nasal cavity; anteriorly, they join with the maxillae. The two horizontal plates articulate with each other at the posterior part of the median palatine suture and more anteriorly with the maxillae at the transverse palatine suture.〔 The human palatine articulates with six bones: the sphenoid, ethmoid, maxilla, inferior nasal concha, vomer and opposite palatine. There are two important foramina in the palatine bones that transmit nerves and blood vessels to this region: the greater and lesser palatine). The larger greater palatine foramen is located in the posterolateral region of each of the palatine bones, usually at the apex of the maxillary third molar. The greater palatine foramen transmits the greater palatine nerve and blood vessels. A smaller opening nearby, the lesser palatine foramen, transmits the lesser palatine nerve and blood vessels to the soft palate and tonsils. Both foramina are openings of the pterygopalatine canal that carries the descending palatine nerves and blood vessels from the pterygopalatine fossa to the palate.〔 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「Palatine bone」の詳細全文を読む スポンサード リンク
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