Bones Flashcards
Bones of face
- Mandible
- Two maxillae
- Two zygomatic(cheek bones)
- Vomer
- Two palatine
- Two nasal
- Two lacrimal
- Two inferior nasal conchae
Maxilla shape
- Large hollow body
- Four projecting processes of bone
Parts of maxillae
- Body
- Maxillary sinus/antrum
- Bony processes
Shape of body of maxilla
- Four sided, hollow pyramid
- Base oriented vertically toward nasal cavity
-Apex extending laterally toward Zygomatic bone
Superior portion of maxilla forms
Floor of orbit of eye(location of infraorbital fissure which becomes infraorbital canal)
-(Infraorbital nerves and vessels exit canal on face through infraorbital foramen)
Foramen on the anterior surface of body of maxilla
Infraorbital foramen
Sinus
-Hollow space within bones
-Found on Sphenoid, Frontal, Ethmoid and Maxilla bones
Function of maxillary sinus
(a) lighten the skull, (b) give resonance to the voice, (c) warm breathed air (d) moisten the nasal cavity
Capacity of maxillary sinus
15ml/1 tablespoon
Shape of Maxillary sinus
- Large four sided, pyramid shaped cavity
- On body of each maxilla
Importance of Maxillary sinus and teeth
-Sinus floor extends onto superior portion of maxillary alveolar process(apices of molar and premolar roots found)
-Very thin bone between sinus and roots or no bone replaced with PDL fibres
Enter the maxilla and sinus
- Nerves to maxillary molars(PSA nerve)
- Enter through alveolar canals
can be mistaken for tooth pain
Infection in sinus
Maxillary sinus opens into
-Nasal cavity from anterosuperior wall
Bony processes of each maxilla
–Frontal(nasofrontal)process
-Zygomatic process
-Alveolar process
-Palatine process
Frontal (nasofrontal) process
-Medial edge joins with nasal bone and frontal bone
Zygomatic process
- Bulky, forms anterior facial surface of each maxilla
- Joins with maxillary process of Zygomatic bone
Mandible
- Largest and strongest bone of the facial skeleton
- Develops in two halves that unite early and ossify during first year of life
Mandible parts
- Body (horseshoe-shaped)
- Ramus (flat, wide bone extending superiorly from the body)
- Alveolar ridge -Coronoid process
- Condyloid process
-Mandibular notch
The mandible articulates with
-Surface of squamous part of temporal bone
Important landmarks of mandible
- Symphysis menti
- -Mental protuberance*
- -Mental foramen*
- -Inferior margin of the mandible*
- -Mandibular notch*
- Mandibular foramen*
- -Lingula*
- -Mental spines*
- -Sublingual fossa*
- -The digastric fossae*
- -The mylohyoid line*
- -Submandibular) fovea*
Symphysis menti
-A median ridge at the site of embryonic fusion
Mental protuberance
Triangular area at the inferior end of symphysis menti and is surrounded by the smaller mental tubercles
Mental foramen
- Located 2.5 cm from the midline between the first and second premolars
- Transmits the mental vessels and nerve
Mandibular notch
-Concavity of the upper border of the ramus between the coronoid and the condylar processes -Transmits the motor nerve and vessels to the masseter muscle
Mandibular foramen
- Near centre of the medial surface of the ramus of the mandible
- Transmits the inferior alveolar nerve and vessels to the teeth
Lingula
Spur of bone overhanging the mandibular foramen
Mental spines
Mark the insertions of the genioglossus and geniohyoid muscles
The sublingual fovea
- Located on each side of the genial tubercle
- Adjacent to the sublingual gland
The digastric fossae
-Attachment of the anterior belly of the digastric muscle
The mylohyoid line
-located behind the sublingual fovea
-Marks the attachment of the mylohyoid muscle
Submandibular fovea
-Below the mylohyoid line is adjacent to the submandibular gland
