
Jaw: Understanding its Parts and Function
Understanding the parts of your jaw and its functions
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of most animals.
Jaw anatomy:Your jaw consists of a pair of bones that form the framework of the mouth of vertebrate animals, usually containing teeth and including a movable lower jaw (mandible) and fixed upper jaw (maxilla). Jaws function by moving in opposition to each other and are used for biting, yawning, laughing, talking, chewing, and the handling of food.
Main Parts of the Jaw
- Maxilla: The upper jawbone that holds the top teeth in place. It’s fixed to the skull and supports the muscles used for chewing and facial expressions.
- Mandible: The lower jawbone that holds the bottom teeth in place. It’s movable and connected to the skull by the temporomandibular joints (TMJs).
- Temporomandibular joints (TMJs): The two joints that connect the mandible to the skull, one on each side.
Main function of the jaw
The jaw’s main function is to chew food, which breaks it down into smaller, more digestible pieces. The jaw also plays a role in speech, facial aesthetics, and the respiratory system. To under how your jaw should function, you need to know how your mandible should function. The mandible consists of a horizontal arch, which holds the teeth and contains blood vessels and nerves. If this is not fuctioning as it should, you may experience painful jawlock.
Your Jaw and Musculoskeletal System
The “jaw” is considered part of the musculoskeletal system, specifically referring to the temporomandibular joint (TMJ) which connects the lower jawbone (mandible) to the skull, and is controlled by a group of muscles called the “muscles of mastication” allowing for jaw movements like opening, closing, and side-to-side motion, essential for chewing and speaking; any dysfunction in this system can lead to conditions like temporomandibular joint disorder (TMJ disorder) with symptoms like jaw pain, clicking, and limited movement.
The jaw muscles move the jaw in a complex three-dimensional manner during jaw movements. There are three jaw-closing muscles (masseter, temporalis, and medial pterygoid) and two jaw-opening muscles (lateral pterygoid and digastric). The basic functional unit of muscle is the motor unit.
“The upper jaw is firmly attached to the nasal bones at the bridge of the nose; to the frontal, lacrimal, ethmoid, and zygomatic bones within the eye socket; to the palatine and sphenoid bones in the roof of the mouth; and at the side, by an extension, to the zygomatic bone (cheekbone), with which it forms the anterior portion of the zygomatic arch. The arched lower part of the maxilla contains the upper teeth. Inside the body of the bone is the large maxillary sinus.” – Parts of the jaw
Why does my jaw hurt?
Jaw pain can occur due to several reasons, most often it is from teeth grinding (bruxism), temporomandibular joint (TMJ) disorders caused by stress or misaligned bite, dental issues like toothaches or gum disease, sinus infections, jaw injuries while play sports, or even stress-related clenching of the jaw muscles.
You may try resting a bit, taking one or two tablets of over-the-counter pain relief, and applying ice to your jaw area.
If your jaw pain is severe, persistent, or accompanied by other symptoms like swelling or difficulty opening your mouth, consult a healthcare professional immediately. If this is your scenario, consider seeing an orofacial pain specialist, as they are dental professionals specifically trained to diagnose and treat pain in the jaw, face, mouth, and neck area, particularly related to conditions like Temporomandibular Joint Disorder (TMJ)
Why is the jaw so important in daily functions?
Your teeth and jaws typically work hard without any thought. They allow us to soften solid foods by chewing them, and also to take a bite out of harder foods like apples, and then help us cut them down to size in our mouths.In order for your teeth to accomplish this, the interactions between the bones of your jaw and the chewing muscles need to function properly too.
A pulled jaw muscle can inhibit normal jaw functioning and be very painful.