(1) Front: Also known as the face, there is an oval-shaped infraorbital foramen about 0.5cm below the midpoint of the infraorbital rim, through which nerves and blood vessels pass. The orientation of the infraorbital foramen is: antero-inferior and medial, and the direction leading into the infraorbital canal is posterior-superior and lateral. The infraorbital foramen is an effective needle insertion site for infraorbital nerve block anesthesia. The levator anguli oris muscle originates from the canine fossa, which is located above the apices of the premolars. In front of the canine fossa and above the maxillary incisors is a shallow incisal fossa.

(2) Posterior: below the temporal surface, toward the posterior and outward sides. There is a zygomatic-alveolar ridge at the lateral transition between the posterior and anterior surfaces of the maxillary body, which can be touched on the face or oral vestibule. It is an important symbol for performing upper retroalveolar nerve block anesthesia. There is a relatively rough rounded bulge in the lower part of the back, called the maxillary tubercle, which is the starting point of the superficial head of the medial pterygoid muscle.

(3) Above: Also called the orbital surface, it is triangular in shape and constitutes most of the infraorbital wall. The infraorbital canal is about 1.5cm long. When performing infraorbital canal anesthesia, the needle should not be inserted too deep to avoid the needle tip passing through the infraorbital groove and damaging the eyeball.

(4) Inner surface: Also called the nasal surface, it forms the lateral wall of the nasal cavity. The pterygopalatine canal is about 3.1cm long, and the descending palatine artery and palatine nerve pass through it. Clinically, maxillary nerve block anesthesia can be performed through the pterygopalatine canal.

(1) Frontal process: located above the body of the maxilla.

(2) Zygomatic process: A cone-shaped protrusion formed by the front and back surfaces of the maxillary body. It connects to the zygomatic bone outwards and downwards to the first molar to form the zygomatic alveolar ridge.

(3) Palatine process: It is a horizontal bone plate. Anesthetic drugs can be injected into the incisor foramen or incisor canal when anesthetizing the nasopalatine nerve. The posterior edge of the palatine process is serrated and connected to the horizontal part of the palatine bone.

(4) Alveolar process: It is arch-shaped. The buccal and labial bone plate of the alveolar process is thin and has many small holes leading to the cancellous bone. Therefore, local infiltration anesthesia can be used clinically for treatment or surgery on maxillary teeth, gums, and alveolar bones. The maxillary alveolar process and the horizontal part of the palatine bone together form the greater palatine foramen, through which the anterior palatine nerve passes. Greater palatine foramen: The surface mark is located at the intersection of the middle and outer 1/3 of the line connecting the gingival margin of the maxillary third molar to the midpalatal suture, about 0.5cm from the posterior edge of the hard palate. (bone mark)

(1) Alveolar socket: The alveolar socket of the maxillary canine is the deepest, and the maxillary first molar has the largest alveolar socket. The wall around the alveolar socket is called the proper alveolar bone and is surrounded by the periodontal ligament. There are many small holes in the inherent alveolar bone, called cribriform plates or cribriform plates. Because it is dense, a white linear image appears on X-ray surrounding the periodontal ligament, so it is called a hard bone plate.

(2) Alveolar ridge: the free edge of the alveolar fossa

(3) Alveolar interval: the alveolar process between two teeth.

(4) Root interval: the alveolar process between the roots of multi-rooted teeth.

(1) Canine pillar: nasofrontal pillar. It mainly bears the masticatory pressure in the canine area, originates from the alveolar process in the maxillary canine area, and goes up along the outer edge of the piriform foramen and the inner edge of the orbit through the frontal process to the frontal bone.

(2) Zygomatic process pillar: It mainly bears the chewing pressure of the first molar area. It originates from the alveolar process of the maxillary first molar area. It goes up along the zygomatic alveolar ridge to the zygomatic bone and then divides into two branches. One branch runs along the frontal process of the zygomatic bone. It passes through the outer edge of the orbit and reaches the frontal bone at the lateral end of the superior orbital edge. The other branch passes backward and outward through the zygomatic arch to the base of the skull.

(3) Pterygoid pillar: Also called pterygomaxillary pillar, it mainly bears the chewing pressure in the molar area and is formed by connecting the pterygoid process of the sphenoid bone and the rear end of the alveolar process of the maxilla.

(1) Le Fort I type maxillary fracture line: from the lower part of the piriform foramen parallel to the base of the alveolar process through the maxillary tubercle to the pterygoid process of the sphenoid bone.

(2) Maxillary Le Fort II fracture line: from the nasal bone, lacrimal bone, and below the zygomatic bone to the pterygoid process of the sphenoid bone

(3) Maxillary Le Fort III fracture line: passes through the nasal bone, lacrimal bone, orbital floor, and above the zygomatic bone to the pterygoid process of the sphenoid bone. (cerebrospinal fluid fistula)

According to the content ratio of compact bone to cancellous bone and the density of cancellous bone, it can be divided into four categories:

3. Age-related changes in the maxillary bone

(1) Inner surface: There is a mandibular hole slightly behind the center, which is funnel-shaped and the opening faces backward and upward. In front of the foramen is the mandibular uvula, which is the attachment point of the sphenomandibular ligament.

(2) Externally: The position of this protrusion is approximately equivalent to the front and back of the medial mandibular foramen and near the upper edge of the upper edge of the mandibular foramen. When performing mandibular ramus surgery (such as orthognathic surgery), the lateral protuberance of the mandibular ramus can be used as a landmark to protect the inferior alveolar nerve and blood vessels on the inside of the mandibular ramus.

(3) Four edges: upper edge, lower edge, trailing edge, front edge

(4) Coracoid process: Also called muscle process, it is flat and triangular in shape. There are temporalis muscle and masseter muscle inside and outside. When the zygomatic bone is fractured, it can compress the coracoid process and affect mandibular movement.

(5) Condylar process: one of the main growth centers of the mandible. If this area is damaged or destroyed before development is completed, it will affect the growth and development of the mandible and lead to maxillofacial deformity.

(1) Outer surface: Also called temporal surface, it is smooth and slightly convex and is the main part of the temporal fossa. The depression between the anterior end of the ridge and the superior posterior quadrant of the external auditory canal is the supracanal triangle. The upper edge of the zygomatic arch is thin and attached to the deep temporal fascia; the lower edge is short arch-shaped and is the origin of the masseter muscle.

(2) Inner surface: Also known as the cerebral surface, it is adjacent to the temporal lobe of the brain and has the middle meningeal artery groove. The inner surface is bounded inferiorly by the petrosquamous fissure, which is separated from the petrous part of the temporal bone.

There is a curved sigmoid sinus groove

Cone-shaped with trigeminal nerve

Curved bone plate There is a stylomastoid foramen between the styloid process and the mastoid process, which is the lower opening of the facial nerve canal, through which the facial nerve exits the skull.