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The maxillary first molar is the tooth located laterally (away from the midline of the face) from both the maxillary second premolars of the mouth but mesial (toward the midline of the face) from both maxillary second molars. The function of this molar is similar to that of all molars in regard to grinding being the principal action during mastication, commonly known as chewing. There are usually four cusps on maxillary molars, two on the buccal (side nearest the cheek) and two palatal (side nearest the palate). There may also be a fifth smaller cusp on the palatal side known as the Cusp of Carabelli. Normally, maxillary molars have four lobes, two buccal and two lingual, which are named in the same manner as the cusps that represent them (mesiobuccal, distobuccal, mesiolingual, and distolingual lobes). Unlike the anterior teeth and premolars, molars do not exhibit facial developmental depressions. Evidence of lobe separation can be found in the central groove, which divides buccal from lingual lobes. The two lingual lobes are separated by the distolingual groove, and the two buccal lobes are divided by the buccal groove. There are great differences between the deciduous (baby) maxillary molars and those of the permanent maxillary molars, even though their function are similar. The permanent maxillary molars are not considered to have any teeth that precede it. Despite being named molars, the deciduous molars are followed by permanent premolars. ==Notation== Permanent Maxillary 1st Molar Notation In the Universal Numbering System, one number is used to identify the tooth. The right permanent maxillary first molar is known as tooth "3", and the left permanent maxillary first molar is known as tooth "14". In the Palmer Notation, a number and symbol are used to identify the tooth. The number identifies the tooth position relative to the midline, and the symbol identifies the quadrant of the mouth. Both Maxillary First Molars have the same number; 6. However, the right molar has the symbol "┘" underneath it. The left molar has "└" underneath it. In the International System of Notation two numbers are used to identify the tooth. The first number identifies the quadrant of the mouth. The second number identifies the tooth relative to the midline of the arch. The right permanent maxillary first molar is known as "16". The left permanent maxillary first molar is known as "26". Deciduous Maxillary 1st Molar Notation In the Universal Numbering System, an uppercase letter is used to identify the tooth. The right deciduous maxillary first molar is known as "B", and the left one is known as "I". In the International System of Notation two numbers are used to identify the tooth. The Right Deciduous Maxillary First Molar is known as "54", and the left one is known as "64". 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「Maxillary first molar」の詳細全文を読む スポンサード リンク
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