Hygiene Atlas

Atlas · Plate I · Head and Neck Anatomy · 01

Skull and facial bones

The skull has 22 bones, 8 cranial and 14 facial, and the mandible is the only one that moves. For hygienists the payoff is the foramina: the mandibular foramen on the inner ramus, the mental foramen near the apex of the mandibular second premolar, and the infraorbital, greater palatine and incisive foramina used as injection landmarks.

High-yield facts · 9

  1. The skull has 22 bones: 8 cranial and 14 facial.S49
  2. The mandible is the only movable skull bone; the maxillae are paired and fuse at the intermaxillary suture.S49T4
  3. The mandibular foramen sits on the medial ramus, about midway between the anterior and posterior borders; the lingula overlaps it.S15
  4. The mental foramen usually lies below the apex of the mandibular second premolar (or between the premolars).S68
  5. The infraorbital foramen lies about 1 cm below the infraorbital rim, roughly in line with the pupil.S17
  6. The greater palatine foramen is usually medial to the maxillary second or third molar, about 1 cm from the gingival margin toward the midline.S16T1
  7. The incisive foramen lies under the incisive papilla, behind the maxillary central incisors.S16
  8. The hyoid bone does not articulate with any other bone.S49
  9. The coronoid notch is the deepest point of the anterior ramus border and is a landmark for the inferior alveolar block.S15

Facts are written in our own words; each tag links to its source. Values marked "sources vary" differ between references, so check the one your program uses.