
Teeth are supported by the bones of the upper and lower jaw, which can lose density and volume due to factors such as gum disease, missing teeth, or conditions like cysts or tumors. The jawbone is living tissue that continually remodels in response to functional demands. Similar to muscles, bone needs to be exercised through the forces generated by chewing to maintain its strength and shape. When a tooth is lost, and no pressure is applied to the bone, it begins to resorb, becoming smaller and thinner over time.
Request an AppointmentConsequences of Bone Loss and Missing Teeth
When teeth are lost, several issues can arise:
- Tooth Shifting: Teeth naturally shift toward the empty space left by a lost tooth. Without an opposing tooth, teeth may erupt or drift out of position. This misalignment can also loosen neighboring or opposing teeth, eventually leading to further tooth loss.
- Loss of Lip Support: The loss of front teeth and the supporting bone can affect the structure of the lips, causing them to sag, which may contribute to wrinkles and skin aging around the mouth.
- Bite Collapse: The loss of posterior (back) teeth, such as molars, can lead to bite collapse or overclosure. This can place excess stress on the jaw joint, eventually causing pain, dysfunction, or arthritis in the joint.
- Difficulty Speaking: The loss of anterior (front) teeth can impair speech. The coordination between the teeth, tongue, and lip muscles is vital for articulation, and missing teeth can make it harder to pronounce words clearly.
- Chewing Function: The ability to chew effectively is directly related to the ability to maintain proper nutrition. Missing teeth can hinder efficient chewing, leading to difficulties in digestion and nutritional absorption.
Causes of Jaw Bone Loss
Patients often ask, “Why did I lose bone?” The following are some of the most common reasons for jawbone resorption:
1. Tooth Extraction
Just as exercise keeps muscles strong, the pressure and forces exerted by teeth during chewing stimulate the jawbone. After a tooth is extracted, the bone no longer has the same functional load, and as a result, the bone begins to resorb. This process occurs most rapidly within the first year following tooth loss, especially in the upper jaw’s anterior region.
2. Periodontal Disease
Periodontal disease, or gum disease, is a slow, progressive condition that destroys the bone supporting the teeth. Plaque and tartar (calculus) cause inflammation in the gums, creating pockets between the gum tissue and the teeth. These pockets trap food particles and bacteria, which release toxins that further irritate the gums and accelerate bone loss. If left untreated, periodontal disease can cause the teeth to loosen and eventually fall out.
3. Dentures and Bridges
Unlike natural teeth or dental implants, dentures and bridges are not anchored directly to the jawbone. Dentures sit on top of the bone, exerting pressure that can accelerate bone resorption. Bridges, while anchored to adjacent teeth, must compensate for the absence of a missing tooth, which can weaken the supporting teeth over time. When one of these supporting teeth fails, the missing tooth space and the broken tooth both require attention. Long-term use of bridges often results in significant bone loss due to lack of stimulation to the bone.
4. Trauma
Accidents, especially sports-related injuries, are common causes of tooth loss or damage. A traumatic injury may only affect the tooth, but if the surrounding bone is fractured, it can also resorb over time. In severe cases, teeth may be knocked out (avulsion), and bone loss can result from the injury.
5. Tumors and Cysts
Tumors and cysts related to the teeth can cause localized bone loss. Impacted wisdom teeth or upper canines are often associated with cysts or tumors, which can grow and resorb the surrounding bone. In severe cases, this bone loss can lead to tooth mobility or fractures of the jaw. Bone grafting may be needed to preserve the integrity of the jaw in these cases.
6. Sinus Enlargement
When posterior teeth in the upper jaw (maxilla) are lost, the sinus cavity may expand, causing a condition called pneumatization. The sinus membrane, which is thin and delicate like an eggshell, can push into the space left by the missing teeth, causing the surrounding bone to resorb. To prevent this, a procedure called a sinus lift may be performed, in which the sinus membrane is gently lifted, and bone is added to the area to preserve bone height and volume.
Maintaining jawbone health is essential for both functional and aesthetic reasons. Proper dental care, timely tooth replacement, and regular checkups are crucial in preventing bone loss and maintaining overall oral health.