Incisive foramina, also known as the median palatine suture or the intermaxillary suture, are bony structures located in the roof of the mouth, specifically in the palatine bone. They are a pair of small openings that allow the passage of nerves and vessels to and from the nasal cavity and the oral cavity.
Structure
The incisive foramina are situated at the midline of the hard palate, which is the bony portion of the roof of the mouth. They are located just posterior to the incisor teeth and anterior to the molar teeth. Each incisive foramen is a small, oval-shaped opening that is surrounded by bone.
The hard palate is formed by the palatine bones, which are a pair of bones that are located on either side of the midline of the skull. The palatine bones are joined together at the midline by the palatine suture, which is also known as the median palatine suture or the intermaxillary suture.
The incisive foramina are formed by a small gap in the palatine suture, which allows the passage of nerves and vessels through the hard palate. The nerves and vessels that pass through the incisive foramina include the nasopalatine nerve and the nasopalatine artery.
Location
The incisive foramina are located in the midline of the hard palate, just posterior to the incisor teeth and anterior to the molar teeth. They are situated between the maxillary bones, which are a pair of bones that form the upper jaw, and the palatine bones, which are a pair of bones that form the roof of the mouth.
They are located at the level of the third molar tooth, which is also known as the wisdom tooth. They are located approximately 2.5 cm posterior to the incisor teeth and 1.5 cm anterior to the molar teeth.
Function
The incisive foramina serve as important passageways for the nasopalatine nerve and the nasopalatine artery. The nasopalatine nerve is a branch of the maxillary nerve, which is one of the three branches of the trigeminal nerve. The nasopalatine artery is a branch of the internal maxillary artery, which is a major artery that supplies blood to the head and neck region.
The nasopalatine nerve and the nasopalatine artery pass through the incisive foramina and enter the nasal cavity, where they supply sensory innervation and blood supply to the nasal septum and the lateral nasal walls. They also supply sensory innervation and blood supply to the hard palate, the gums, and the teeth.
Clinical significance
The incisive foramina are important structures that are involved in a variety of clinical conditions and procedures. Some of the clinical conditions and procedures that may be related to the incisive foramina include:
Dental procedures
The incisive foramina are often used as landmarks during dental procedures, such as root canal therapy, crown preparation, and implant placement. They are also used as landmarks during the placement of dental blocks, which are used to numb the teeth and surrounding tissues during dental procedures.
Anesthesia
The nasopalatine nerve and the nasopalatine artery that pass through the incisive foramina are often used as injection sites for local anesthetic agents, such as lidocaine and bupivacaine, to numb the teeth and surrounding tissues during dental procedures.
Sinus surgery
The incisive foramina are often used as landmarks during endoscopic sinus surgery, which is a type of surgery that is performed to remove obstructions or abnormalities in the sinuses. The incisive foramina are also used as access points for instruments that are used to perform the surgery.
Palatoplasty
Palatoplasty is a surgical procedure that is performed to repair or reconstruct the hard palate. The incisive foramina may be involved in this procedure, depending on the specific type of palatoplasty that is being performed.
Nasal fractures
Nasal fractures, which are also known as broken noses, may involve the incisive foramina if the hard palate is fractured. In this case, the incisive foramina may be displaced or distorted, which can affect the function of the nasopalatine nerve and the nasopalatine artery.
Trauma
The incisive foramina may be damaged or injured in cases of trauma to the head or face, such as car accidents or falls. In this case, the nasopalatine nerve and the nasopalatine artery may be damaged or disrupted, which can cause numbness or tingling in the nose, mouth, and teeth.
Cancer
The incisive foramina may be involved in the spread of cancerous tumors in the head and neck region. Tumors that originate in the oral cavity or the nasal cavity may spread to the incisive foramina and invade the hard palate. In this case, the incisive foramina may be removed or damaged during cancer surgery.
