As reported by the New Haven Register, April 9, 2006.
Implants Are Durable, Comfortable and Look Real
By Abram Katz
Eating and talking are a lot harder without teeth, but until the middle of the 20th century, many people lost them all by the time they reached middle age.
Ancient Egyptians fashioned replacement teeth out of ivory, and South
American civilizations also tried to reimplant lost teeth or substitute
In the 18th century, wealthy people who lost teeth purchased replacements from the poor.
None of these techniques worked very well, because the immune system
does not welcome foreign substances, let alone other people’s incisors
Research continued, and dentists implanted stainless steel, chromium-cobalt alloy and other materials into jaws as anchors for synthetic teeth.
These metals were not very reliable, said Dr. Thomas D. Taylor, prosthodontist and head of rehabilitation, biomaterials and skeletal development at the University of Connecticut School of Dental Medicine.
The new age of dental implants dawned in 1952, when Swedish dentist Ingvar Branemark tried titanium. Branemark fashioned an implant that resembled a metallic wood screw. He introduced a workable implant 30 years later, in 1982.
Titanium is light, strong and — perhaps most importantly — is incorporated into bone and does not trigger an immune response, Taylor said.
Now missing teeth are routinely replaced by synthetic dentition screwed onto titanium posts planted in the upper and lower jaws. The procedure is still expensive, but correctly installed implants are durable, cause little discomfort and are difficult to distinguish from real teeth, said Dr. Stephen H. Guss, of Cosmetic & Reconstructive Dentistry Associates in Fairfield.
Brushing, proper flossing, periodic cleaning and dental exams can help people keep their own teeth, which is the best alternative, Taylor said.
Trauma — car crashes and other accidents — knock out many teeth. However, gum disease and the long-term consequences of dental decay are the main causes of tooth loss, according to the American Dental Association.
Even today, with fluoride, X-rays and other advances in tooth care, about 30 percent of adults 65 and older are toothless.
Years ago, a broken or missing tooth was corrected with a "bridge," a dental appliance attached to adjacent teeth, said Dr. Donald W. Miller of Cosmetic & Reconstructive Dentistry. The supporting teeth often had to be filed down.
Do nothing to replace a missing tooth and bone in the jaw thins and disappears, Taylor said. This can endanger surrounding teeth.
Implants solve these problems by providing a solid anchor for new teeth and halting erosion of alveolar bone within the jaw.
But sinking titanium screws into a jaw is not like working on a piece of wood, Miller said.
Areas of eroded jaw bone may have to be filled with bone from a cadaver, bovine bone or a preparation of sea coral, Taylor said.
The anchor must not hit any nerves. The bone separating the upper jaw from the sinus is thin and care has to be taken to avoid breaching the space, Miller said.
"We start with an end result, make wax computer models, and then work backward, growing the bone accordingly," Guss said.
X-rays are also used to avoid nerves. Guss and Miller said the precise wax model and X-rays ensure that the implant is oriented and placed precisely.
The actual drilling is done with an extremely sharp bit that turns slowly to avoid producing heat that might damage surrounding tissue. The displaced bone is mixed with a catalyst that stimulates bone-producing osteoblast cells, Miller said.
This mixture can be used to augment the jaw or strengthen the sinus wall. It can also be placed around viable teeth to preserve them. Sometimes the augmenting bone is inserted under the mucosal lining in the sinus.
When the hole is ready, the titanium hex-head hardware is screwed carefully into place. The top of the anchor is threaded so that the replacement tooth can be screwed tightly into place.
Miller said the implant success rate has risen to about 98 percent. While the procedure may sound painful, it is performed under the care of an anesthesiologist and there is little post-implant discomfort, Guss said.
After a patient is prepared and his mouth photographed and modeled, six to eight implants can be installed at once, Miller said.
"Attitudes about teeth are changing. There are better options now," he said.
People often obtain dental implants after divorces and before they return to dating, he said. Another popular reason is to look younger for purposes of employment.
Implants can also be used to anchor dentures or instead of dentures, Taylor said. Sometimes a space is purposely left between the lower gums and the denture to permit easy cleaning, he said.
"Implants are extremely durable. Risk factors for failure are smoking and uncontrolled diabetes. It’s a surprisingly benign procedure," Taylor said.
Taylor said the original Branemark technique called for installation of the posts, suturing the gum tissue and then waiting for the bone to heal for four to six months. The tips of the posts were then exposed and teeth attached. Most implants now are not "submerged" in this way, he said.
The "teeth" that are attached to the anchors are made out of porcelain-covered gold, solid ceramic or resin, he said. Each tooth must be custom made to match the color, shape, opacity and size of surrounding teeth, he said.
"There is no off-the-shelf tooth," he said.
Consequently, the teeth are expensive. The cost of implanting one tooth includes the fee for the implant and tooth, and the fee for preparing the jaw and installing the anchor and tooth, Taylor said.
That comes to about $3,500 to $4,000 and many dental insurance plans do not cover implants, he said. Generally, the cost-per-implant drops if the patient desires several replacements.
The UConn dental school offers a good deal for people who want tooth implants, Taylor said. If you don’t mind supervised dental students working on your teeth and jaw, the cost per tooth is about $600.
As the population ages, the demand for implants is sure to rise, Taylor said.