Dental Implants were first developed in Europe by Dr. Branemark in the mid-1970’s. Since the introduction of dental implants, they have gone through a transformation in shape, external and internal design, thread count and pitch, surface texture, taper and placement techniques. Dental implants have transformed the practice of dentistry giving unlimited possibilities.
When a patient was missing a tooth the traditional treatment was either a bridge or partial denture or nothing! With a bridge, the dentist would have to remove good tooth structure to prepare the tooth for a crown. This would be done on both sides of the missing tooth to prepare the site for a bridge. This restorative choice replaces the missing tooth at the detriment of viable tooth structures and hygiene. With a bridge, patients eventually drop flossing under the bridge allowing new cavities to form on the inner surface of the bridge. As a result, the national average life span for a bridge is 10-12 years. When the bridge fails additional tooth structures will need to be removed to remake the bridge and this often leads to endodontic or root canal therapy.
Partial Denture Dental Implants
The other alternative is a partial denture. This is a prosthesis made of metal and acrylic that uses precise clasps on other teeth to help retain the partial denture. This option may be the best if you are missing multiple teeth and a low cost is your primary concern. Through careful treatment planning with your restorative dentist, dental implants can change your life by restoring your smile and the chewing molars. Most people are candidates but a comprehensive consultation with Dr. Johnson and your restorative dentist will determine the best options. Dental Implants are made of titanium and resemble a drywall screw. They are placed into the upper or lower jaw and are used to place a crown or even to help support a denture. The most important criteria is bone quality and quantity. Think of bone as the concrete foundation that a home is built upon. Without adequate healthy bone or concrete, a dental implant will fail and the house will fall.
There needs to be suitable bone circumferential and apical, or underneath, of the dental implant. Notice the picture to the right and the needed bone around the implant.
This picture also demonstrates that it is possible to remove a tooth and place an implant at the same time because the shape is similar but it requires healthy bone to support the dental implant. If the tooth had an abscess or periodontal disease (bone loss) the immediate placement of a dental implant might not be appropriate or possible. In this situation Dr. Johnson would choose to place a site preservation graft or more commonly called, socket graft. Placement of a xenograft graft (graft from another species) into an immediate extraction site accomplishes two important goals. First, when a tooth is extracted the natural healing process resorbes the existing native bone, especially the bone that you can see when you smile, called the facial plate. This happens because the tension stress that occurs while a tooth is functioning is lost. The body assumes the bone that supported the tooth is no longer needed and resorption occurs. The immediate graft will help preserve this native bone by slowing the body’s resorption. The second goal the xenograft accomplishes is to stimulate bone growth into the socket which allows a dental implant to be placed sooner after the extraction, usually within 3 months. The most common type of xenograft is bovine (cow) which is readily available and has a long history of success in the dental literature.
Dental implants are still possible if you have lost a tooth years ago because not all patients have the resorption that was discussed above or Dr. Johnson can perform an onlay graft to build the width of the alveolar bone. Onlay grafting is a technique in dental implant surgery that allows Dr. Johnson to widen the existing bone to allow an appropriate sized dental implant to be placed. Remember, a potential dental implant site needs a specific type of dental implant, one size does not fit all in implant therapy.
In some cases a sinus lift may need to be performed. The maxillary sinus is an air filled cavity within our upper jaw that is located just above the molars. As we age the sinus naturally pneumatizes, or enlarges, and when combined with an old extraction site can create a lack of bone depth. Even though implants come in a variety of lengths, from 8.5mm to 15mm long, the existing bone depth may be less. As a result Dr. Johnson may need to perform a sinus lift which places new bone into the sinus to increase the existing depth. Please keep in mind that any graft, including a sinus lift, needs 6 months of healing before dental implants can be placed.