Guide to Dental Implants
Only a few decades ago, people who lost their teeth due to gum disease, neglect or accidents were relegated to wearing full or partial dentures to replace some or all of their teeth. Dental implants now allow dentists to replace individual teeth, create a tooth bridge or create denture supports that are much more natural and better-fitting than normal dentures.
The Problem with Dentures
Dentures are used by millions of people and have been around for centuries. However, they have several problems. Many years of denture use routinely causes resorption (a wearing away) of the basal and alveolar bone found in our upper and lower jaws. This bone loss causes a denture to become unstable. Dentures, especially those that are ill fitting, can make eating, speaking and smiling a chore.
People who have lost bone in their jaws due to years of denture use can also expect changes in their appearance. A person's face will show exaggerated signs of aging because the bone loss in their jaws can cause the chin to jut forward, and also to shorten the distance between the chin and nose. The groove between the nose and corner of the lip (nasolabial angle) deepens, and the muscles of the face can sag, causing unsightly jowls or the dreaded witch's chin.
Fortunately, dental implants, a discovery by Swedish scientist and orthopedic surgeon, Dr. P.I. Brånemark, have led to a vastly improved quality of life for the many people who suffer from the problems associated with missing teeth. Dental implants are titanium rods about a centimeter long that are placed inside the jawbone and serve the same purpose as the roots of teeth. They can replace missing teeth and prevent bone loss under dentures. Implants may have a smooth texture, or can be threaded, perforated, hollow, solid, coated or textured. One common coating for implants is hydroxyapatite, which has the same composition as the mineral content of our bones.
Implant dentistry involves careful planning and highly trained and experienced dentists. The implant procedure is usually planned by the patient's general dentist or a prosthodontist (specialist in placing crowns and bridges). The dentist must first discuss with the patient what their goals are, and then must give the patient all of their options, expected outcome, risks and benefits. Every dental situation is unique, and in many cases, there are several alternatives for replacing missing teeth other than dental implants. The medical and social histories of the patient are also important. Diseases that affect the immune system such as diabetes, and habits that reduce blood flow and healing such as smoking, must be identified because they can reduce the success of implant surgery.
The Implant Procedure
Study models of the patient's jaws are necessary for the planning stage of an implant procedure, and are made from molds (impressions) of the mouth. A surgical stent is then made from the model to give to the dental surgeon a guide when placing the implant(s). An X-ray of the jaw is required, both individual (periapical) X-rays, and an X-ray of the entire mouth (panoramic). In some cases, a computer-assisted tomography (CAT scan) is advisable to give the dentist a more accurate representation of the amount of jawbone available for dental implants. The dentist will also need a clinical examination to determine if there is enough bone width to fit an implant. If the implant is being used to replace a single tooth, there needs to be adequate room between the existing teeth so that the implant does not damage the surrounding tooth roots.
If the X-ray or CAT reveals that there is not enough bone height to place the implant, a bone graft may be required. If the maxillary (upper jaw) sinus is in the area where implants need to be placed, a procedure called a sinus lift must be performed. If a bone graft or a sinus lift is required, the procedure becomes more involved. With a sinus lift procedure, a small window of bone is formed and the delicate membrane of the sinus is pushed up. Bone can then be grafted into the area where the sinus was. Many dental surgeons prefer to use bone from the patient (an autogenous graft) to add the needed jawbone height to place implants. The grafts are usually taken from the iliac crest of the hip, a different area of the jaw, or the skull.
Although any dentist can surgically place implants into the jaw, a dental specialist called a periodontist (gum disease specialist) or an oral surgeon (specialist who does more advanced tooth extractions and other dental surgery) is most commonly used for the procedure. To place a dental implant, the dentist uses local anesthesia to numb the surgical area. In most cases, the procedure is well tolerated by the patient, and can be done while the patient is awake, or with light dental sedation. An incision is made into the gum to expose the underlying bone. The stent is then placed over the jaw to guide the implant placement. A series of drills in progressively widening diameters are used to create a hole in the bone. The implant is then placed into the hole so that the top of the implant is at or slightly above the crest (top) of the bone, where it meets the gum line. A screw is inserted into the implant to prevent the gum and other debris from entering the implant. The gum is then stitched up over the implant. The first stage of the implant surgery is then complete.
After implant surgery, denture wearers will be asked not to use their dentures for two weeks as the implants heal. An antiseptic mouth rinse containing chlorhexidine gluconate such as Peridex® is usually given during the first few weeks after implant surgery. Antibiotics and pain medication are prescribed routinely to prevent infection and alleviate pain.
After the implants are placed, they require three to nine months to connect to the jawbone. The lower jaw (mandible) generally requires three to six months, and the upper jaw (maxilla) requires six to nine months. This process, where bone grows into the implant, is called osteointegration. Once connected to the bone, tooth crowns, permanent dental bridges or dentures can be fastened to the implants.
Several months after the implant surgery, a second surgery is performed to remove the cover screw and attach a larger screw, called a healing cap, to the implant. The healing cap sticks out above the gum. An X-ray is taken to confirm that the bone has attached to the implant, and that osteointegration has occurred.
Building on the Implant
A series of procedures are performed by the general dentist or prosthodontist to build the tooth or provide a substructure for a denture. Implants can be used to either replace a single tooth, several teeth, or support a bar or other attachment that secures a denture. These procedures are varied and highly specific for each person and each situation. The procedures generally include multiple visits where impressions are taken, temporaries are made, and adjustments required to achieve optimal results.
Implants are especially useful when securing loose dentures. Although there are many different types of attachments for dentures, I prefer magnets. Magnets are very predictable, cost-effective, low maintenance and create a very tight bond between the implant and the denture. The use of magnets in dentistry gets a bad rap because they have a reputation for corroding over time and causing an ugly metallic stain in the denture. The difference today is that the magnets are encased in plastic, eliminating this problem.
The success rate of dental implants varies, but a well planned and skillfully executed case approaches 90 percent, possibly higher in implant denture cases. Anyone considering dental implants, and who hopes to have a successful result, must be committed to performing excellent oral hygiene around the implant, and come to his or her dentist at least twice a year for maintenance. The cost of a single implant includes the surgical cost and the cost of the tooth connected to it.
If you're interested in getting dental implants, call us at 1-866-970-0441. We'll put you in touch with a great dentist today!