Reasons for Jawbone Loss and Deterioration
The following are the most common causes for jawbone deterioration and loss that may require a bone grafting procedure:
- Tooth extractions
- Periodontal disease
- Dentures & bridgework
- Congenitally missing teeth
- Sinus proximity or enlargement
When an adult tooth is removed and not replaced, jawbone deterioration may occur. Natural teeth are embedded in the jawbone, and stimulate the jawbone through activities such as chewing and biting. When teeth are missing, the alveolar bone, or the portion of the jawbone that anchors the teeth in the mouth, no longer receives the necessary stimulation, and begins to break down, or resorb. The body no longer uses or “needs” the jawbone, so it deteriorates and goes away.
The rate the bone deteriorates, as well as the amount of bone loss that occurs, varies greatly among individuals. However, most lost occurs within the first six to eight weeks the extraction, and continues throughout life.
Periodontitis is caused by bacteria that adhere to the tooth’s surface, along with an overly aggressive immune response to these bacteria. If gingivitis progresses into periodontitis, the supporting gum tissue and bone that holds teeth in place deteriorates. The progressive loss of this bone, the alveolar bone, can lead to loosening and subsequent loss of teeth.
Unanchored dentures are placed on top of the gum line, and therefore do not provide any direct stimulation to the underlying alveolar bone. Over time, the lack of stimulation causes the bone to resorb and deteriorate. Because this type of denture relies on the bone to hold them in place, people often experience loosening of their dentures and problems eating and speaking. Eventually, bone loss may become so severe that dentures cannot be held in place even with strong adhesives, and a new set may be required. Proper denture care, repair, and refitting are essential to maintaining oral health.
Dental implants can anchor dentures and also adequately stimulate and preserve bone. If bone has been lost, Drs. Mentzel, Meraw, and Plonka may perform bone grafting procedures to allow implant placement.
A bridge involves using adjacent teeth to support replacement crowns for missing teeth. This requires shaving down supporting teeth and fitting them with crowns connected to the replacement teeth. The supporting teeth do provide stimulation to the bone, but the portion of the bridge that spans the gap where the teeth are missing receives no direct stimulation. Bone loss can occur in this area, therefore, dental implants may be a better solution. Also unlike bridges, implants leave the adjacent teeth intact and untouched.
When a tooth is completely knocked out, bone stimulation stops, which results in jaw bone loss. When a tooth is broken, it can be susceptible to infection, leading to jaw bone loss. Some common forms of tooth and jaw trauma include: teeth knocked out from injury or accident, jaw fractures, or teeth with a history of trauma that eventually die and lead to bone loss years after the initial trauma.
Periodontists specialize in careful removal of broken-down teeth to preserve the remaining bone. A bone grafting procedure may be needed to reverse the effects of bone deterioration, allowing for the placement of dental implants in an ideal position.
CONGENITALLY MISSING TEETH:
Some individuals may be missing certain teeth congenitally, like lateral incisors. Since these teeth were never present, the underlying bone may be weak or minimal and require bone grafting to support dental implant placement.
Sinus Proximity or Enlargement:
When molars are removed from the upper jaw, air pressure from the air cavity in the maxilla (maxillary sinus), causes resorption of the bone that formerly helped the teeth in place. As a result, the sinuses become enlarged (“hyperpneumatized”). This condition may result in insufficient bone for the placement of dental implants. Drs. Meraw or Plonka can perform a procedure called a “sinus lift” that can allow implant placement.
Osteomyelitis is a bacterial infection in the bone and bone marrow of the jaw. Treatment for osteomyelitis generally requires antibiotics and removal of the affected bone. A bone graft procedure may then be required to restore bone function and esthetics lost during removal, and support implants to replace missing teeth.
Both benign and malignant tumors may require removal of a portion of the jaw. In both cases, reconstructive bone grafting is usually required to help restore function to the jaw.