MANDIBLE
ATTACHMENTS AND RELATIONS OF THE MANDIBLE OSSIFICATION AGE CHANGES
IN THE MANDIBLE STRUCTURES RELATED TO MANDIBLE CLINICAL ANATOMY
The mandible, or the lower jaw, is the largest and the strongest bone of the face.
It develops from the first pharyngeal arch.
It has a horseshoe-shaped body which lodges the teeth, and a pair of rami which
project upwards from the posterior ends of the body.
The rami provide attachment to the muscles of mastication
Inner surface of mandible Outer surface of mandible
BODY
Each half of the body has outer and inner surfaces, and upper and lower borders.
The outer surface presents the following features.
1) The symphysis menti is the line at which the right and left halves of the bone meet
each other. It is marked by a faint ridge
2) The mental protuberance (mentum = chin) is a median triangular projecting area in
the lower part of the midline. The inferolateral angles of the protuberance form the
mental tubercles.
3) The mental foramen lies below the interval between the premolar teeth.
4) The oblique line is the continuation of the sharp anterior border of the ramus of the
mandible. It runs downwards and forwards towards the mental tubercle.
5) The incisive fossa is a depression that lies just below the incisor teeth.
The inner surface presents the following features.
, 1) The mylohyoid line is a prominent ridge that runs obliquely downwards and forwards
from below the third molar tooth to the median area below the genial tubercles.
2) Below the mylohyoid line, the surface is slightly hollowed out to form the
submandibular fossa, which lodges the submandibular gland.
3) Above the mylohyoid line, there is the sublingual fossa in which the sublingual gland
lies. d. The posterior surface of the symphysis menti is marked by four small
elevations called the superior and inferior genial tubercles.
4) The mylohyoid groove (present on the ramus) extends onto the body below the
posterior end of the mylohyoid line. The upper or alveolar border bears sockets for
the teeth. The lower border of the mandible is also called the base. Near the midline,
the base shows an oval depression called the digastric fossa.
RAMUS
The ramus is quadrilateral in shape and has:
• Two surfaces—lateral and medial
• Four borders—upper, lower, anterior and posterior
• Two processes—coronoid and condyloid.
The lateral surface is flat and bears a number of oblique ridges. The medial surface
presents the following.
The mandibular foramen lies a little above the centre of ramus at the level of occlusal
surfaces of the teeth. It leads into the mandibular canal which descends into the
body of the mandible and opens at the mental foramen.
The anterior margin of the mandibular foramen is marked by a sharp tongue-shaped
projection called the lingula. The lingula is directed towards the head or condyloid
process of the mandible.
The mylohyoid groove begins just below the mandibular foramen, and runs
downwards and forwards to be gradually lost over the submandibular fossa.
o The upper border of the ramus is thin and is curved downwards forming the
mandibular notch.
o The lower border is the backward continuation of the base of the mandible.
Posteriorly, it ends by becoming continuous with the posterior border at the angle of
the mandible.
o The anterior border is thin, while the posterior border is thick.
The coronoid (Greek crow’s beak) process is a flattened triangular upward projection from
the anterosuperior part of the ramus. Its anterior border is continuous with the anterior
border of the ramus. posterior border bounds the mandibular notch.
ATTACHMENTS AND RELATIONS OF THE MANDIBLE OSSIFICATION AGE CHANGES
IN THE MANDIBLE STRUCTURES RELATED TO MANDIBLE CLINICAL ANATOMY
The mandible, or the lower jaw, is the largest and the strongest bone of the face.
It develops from the first pharyngeal arch.
It has a horseshoe-shaped body which lodges the teeth, and a pair of rami which
project upwards from the posterior ends of the body.
The rami provide attachment to the muscles of mastication
Inner surface of mandible Outer surface of mandible
BODY
Each half of the body has outer and inner surfaces, and upper and lower borders.
The outer surface presents the following features.
1) The symphysis menti is the line at which the right and left halves of the bone meet
each other. It is marked by a faint ridge
2) The mental protuberance (mentum = chin) is a median triangular projecting area in
the lower part of the midline. The inferolateral angles of the protuberance form the
mental tubercles.
3) The mental foramen lies below the interval between the premolar teeth.
4) The oblique line is the continuation of the sharp anterior border of the ramus of the
mandible. It runs downwards and forwards towards the mental tubercle.
5) The incisive fossa is a depression that lies just below the incisor teeth.
The inner surface presents the following features.
, 1) The mylohyoid line is a prominent ridge that runs obliquely downwards and forwards
from below the third molar tooth to the median area below the genial tubercles.
2) Below the mylohyoid line, the surface is slightly hollowed out to form the
submandibular fossa, which lodges the submandibular gland.
3) Above the mylohyoid line, there is the sublingual fossa in which the sublingual gland
lies. d. The posterior surface of the symphysis menti is marked by four small
elevations called the superior and inferior genial tubercles.
4) The mylohyoid groove (present on the ramus) extends onto the body below the
posterior end of the mylohyoid line. The upper or alveolar border bears sockets for
the teeth. The lower border of the mandible is also called the base. Near the midline,
the base shows an oval depression called the digastric fossa.
RAMUS
The ramus is quadrilateral in shape and has:
• Two surfaces—lateral and medial
• Four borders—upper, lower, anterior and posterior
• Two processes—coronoid and condyloid.
The lateral surface is flat and bears a number of oblique ridges. The medial surface
presents the following.
The mandibular foramen lies a little above the centre of ramus at the level of occlusal
surfaces of the teeth. It leads into the mandibular canal which descends into the
body of the mandible and opens at the mental foramen.
The anterior margin of the mandibular foramen is marked by a sharp tongue-shaped
projection called the lingula. The lingula is directed towards the head or condyloid
process of the mandible.
The mylohyoid groove begins just below the mandibular foramen, and runs
downwards and forwards to be gradually lost over the submandibular fossa.
o The upper border of the ramus is thin and is curved downwards forming the
mandibular notch.
o The lower border is the backward continuation of the base of the mandible.
Posteriorly, it ends by becoming continuous with the posterior border at the angle of
the mandible.
o The anterior border is thin, while the posterior border is thick.
The coronoid (Greek crow’s beak) process is a flattened triangular upward projection from
the anterosuperior part of the ramus. Its anterior border is continuous with the anterior
border of the ramus. posterior border bounds the mandibular notch.
