Facial Bones PDF

Facial bones Dr. Harith Haitham orthopedic surgeon (F.I.C.M.S.) 1. ZYGOMATIC BONE (ZYGOMA) Characteristics  Forms the majority of the skeleton of the cheek.  Provides attachment of the masseter muscle.  Three foramina in the zygoma:  Zygomatico-Orbital foramen. ZygomaticoFacial foramen....

Facial bones Dr. Harith Haitham orthopedic surgeon (F.I.C.M.S.) 1. ZYGOMATIC BONE (ZYGOMA) Characteristics  Forms the majority of the skeleton of the cheek.  Provides attachment of the masseter muscle.  Three foramina in the zygoma:  Zygomatico-Orbital foramen. ZygomaticoFacial foramen. ZygomaticoTemporal foramen.  There are 2 zygomatic bones. Parts: 1. Frontal process  Articulates with the frontal bone to help form the orbit. 2. Temporal process  Articulates with the zygomatic process of the temporal bone to form the zygomatic arch. 3. Maxillary process  Articulates with the zygomatic process of the maxillary bone to help form the orbit. Maxillary process 2. MAXILLARY BONES (MAXILLA) Characteristics  Forms the majority of the skeleton of the face and the upper jaw.  Contains the maxillary paranasal sinus.  Articulates with the opposite maxilla and the frontal, nasal, vomer, and ethmoid bones; inferior nasal concha; palatine, lacrimal, and zygomatic bones; and the septal and nasal cartilages  There are 2 maxilla bones (maxillae) Parts: 1. Body  Major part of the bone  Shaped like a pyramid  Contains the maxillary paranasal sinus  Infraorbital canal and foramen pass from the orbit region to the face region 2. Frontal process  Extends superiorly to articulate with the nasal, frontal, ethmoid, and lacrimal bones  Forms the anterior boundary of the lacrimal fossa 3. Zygomatic process  Extends laterally to articulate with the maxillary process of the zygomatic bone 4. Alveolar process  The part of the maxilla that supports all of the maxillary teeth  Extends inferiorly from the maxilla  Each maxilla contains 5 primary and 8 permanent teeth  Alveolar bone is resorbed when a tooth is lost 5. Palatine process  Extends medially to form the majority of the hard palate  Articulates with the palatine process of the opposite side and the horizontal plate of the palatine bone  Incisive foramen is located in the anterior portion 3. NASAL BONE Characteristics  Inferior portion forms the superior margin of the nasal aperture.  Forms the bridge of the nose.  There are 2 nasal bones.  Articulates with the nasal bone of the opposite side, the nasal portion of the frontal bone, the frontal process of the maxilla, and the perpendicular plate of the ethmoid.  Inferior portion of the nasal bones attaches with the lateral nasal cartilages and septal cartilage. 4. LACRIMAL BONE Characteristics  Lacrimal bone is small and rectangular in shape and very thin and fragile  There are 2 lacrimal bones  Forms a small portion of the medial wall of the orbit  Articulates with the frontal process of the maxilla, orbital plate of the ethmoid bone, the frontal bone, and the inferior nasal concha  The region that articulates with the frontal process of the maxilla forms the lacrimal fossa, the location of the lacrimal sac  The inferior part of the lacrimal forms a small portion of the lateral wall of the nasal cavity 5. VOMER Characteristics  Shaped like a “plough”  Forms the posterior inferior part of the nasal septum  There is 1 vomer bone  Articulates with the perpendicular plate of the ethmoid, maxilla, palatine, and sphenoid bones and septal cartilage  Posterior border does not articulate with any other bone 6. PALATINE BONE Characteristics  Forms part of the nasal cavity and the hard palate, it is L-shaped  There are 2 palatine bones 1. Perpendicular plate  Is in the shape of a vertical rectangle.  On the superior border is a notch that articulates with the sphenoid bone, forming the sphenopalatine foramen.  A small orbital process helps form part of the orbit.  Forms part of the wall of the pterygopalatine fossa and the lateral wall of the nasal cavity.  Lateral wall articulates with the maxilla to form the palatine canal. 2. Horizontal plate  Forms the posterior portion of the hard palate.  Superior to the horizontal plate is the nasal cavity.  On the medial part, formed by both of the horizontal plates, is the posterior nasal spine.  Greater palatine foramen is on this plate. 2. Pyramidal process  Extends posteriorly and inferiorly from the junction of the perpendicular and horizontal plates of the palatine.  Lesser palatine foramina are located here. 7. INFERIOR NASAL CONCHA Characteristics :  Is described as a curved bone that forms part of the lateral wall of the nasal cavity.  There are 2 inferior nasal conchae.  Lies within a curve in the lateral wall of the nasal cavity.  Articulates with the maxilla and perpendicular plate of the palatine, lacrimal, and ethmoid bones. 8. MANDIBLE Characteristics  Forms the lower jaw  Described as horse shoe shaped  All muscles of mastication attach to the mandible  There is 1 mandible Part: 1.  Body  Mental foramen lies on the anterior part of the lateral surface of the body  External oblique line is observed on the lateral side of the mandible  On the medial side of the body lies the mylohyoid line  Mylohyoid line helps divide a sublingual from a submandibular fossa  Posterior border of the mylohyoid line provides for attachment of the pterygomandibular raphe  At the midline on the medial side are the superior and inferior genial tubercles, as well as the digastric fossa 2. Ramus  Meets the body of the mandible at the angle of the mandible on each side  Masseter muscle attaches to the lateral side  Medial pterygoid muscle and sphenomandibular ligament attach to the medial side  Mandibular foramen is located on the medial side of the ramus  Superior part divides into a coronoid process anteriorly and a condylar process posteriorly, separated by a mandibular notch 3. Coronoid process  The anterior most superior extension of each ramus  Temporalis muscle attaches to the coronoid process 4. Condylar process  Articulates with the temporal bone in the temporomandibular joint  Has a neck that forms a condyle superiorly  Lateral pterygoid muscle attaches to pterygoid fovea on the neck 5. Alveolar process  Extends superiorly from the body  Created by a thick buccal and a thin lingual plate of bone  The part of the mandible that supports the mandibular teeth  Each side of the mandible contains 5 primary and 8permanent teeth  Alveolar bone is resorbed when a tooth is lost