Mandibular first molar

Study entry

Location

Socket of the alveolar part of the mandible, behind the second premolar.

Structure

It is the largest tooth of the lower arch. The crown has five cusps, three vestibular and two lingual. It has two roots, mesial and distal; the mesial one usually has two canals. It erupts at about 6 to 7 years.

Neighborhood

The roots lie above the mandibular canal, with the inferior alveolar nerve passing below them.

Blood supply

Inferior alveolar artery, branch of the maxillary, which runs in the mandibular canal and gives a branch to each root; the veins accompany the artery.

Innervation

Inferior dental plexus, formed by the inferior alveolar nerve (CN V3), which runs in the mandibular canal.

Lymphatics

The lymphatic vessels of the tooth and gum drain mainly into the submandibular lymph nodes.

Clinical

It is the first permanent molar to erupt and the tooth most affected by caries and lost early. In some people there is a third root (radix entomolaris).

Source: cap. 8, «Dientes»; tabla 8-13 B (erupción de los dientes permanentes)

Other structures in this region

• Maxillary central incisor
• Maxillary lateral incisor
• Maxillary canine
• Maxillary first premolar
• Maxillary second premolar
• Maxillary first molar
• Maxillary second molar
• Maxillary third molar