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You're relaxing in a fully automated, precision-adjustable chair with a soothing massage feature and temperature control. Soft music fills the room; there's a TV and a fireplace, a comfortable sofa, curtained windows and cut flowers. The only clue that this is a dentist's office—and it may not be much of a clue if you're used to conventional dental techniques—is the small, flat sensor in your mouth. It's connected by a thin wire to a computer, and as you take in the surroundings an x-ray beam is pulsing briefly through your teeth, then into the sensor, which will record the image of the teeth and transmit it to the computer monitor. In three seconds (six for a panoramic view of your teeth) the digital x-ray image will be before your eyes, 400 percent bigger than an ordinary x-ray image. In the "old" days of straight x-raying, you'd be sitting in a sweaty chair for 15 minutes waiting for the film to develop. Moreover, the digital approach cuts your exposure to x-rays by as much as 90 percent, an advantage not only for the patient but for the dentist and technicians who operate the machines.
Now the dentist clicks a mouse, zooming in on a suspicious-looking tooth, rotating, sharpening, and colorizing its image. With the mouse he traces an area of decay, a cavity, clicks again, and prints out a color copy. If you still associate cavities with needles and pain, take heart—to the rescue comes The Wand, a computerized injection system that blots out the sudden prick and burning sensation of a shot (discomfort that is mostly due to the pressure created by the flow of anesthetic.) A thin needle attached to a pen-sized wand is placed near the gum, but before the needle actually makes contact, a drop of anesthetic numbs the surface tissue; as the dentist gently glides the needle into the gum, the tissue just ahead of the needle tip is deadened by the anesthesia—and once the needle is fully inserted, the computer takes over and slowly releases a stream of pain-killer.
Worried about the drill? Put on a pair of goggles, and instead of suffering the anguish of waiting for the terror-triggering whir, all you'll experience is the coolness of an air-abrasion system—a thin, high-speed stream of air-blown microscopic particles that gently remove decay from your tooth in a jiffy. A couple of missing front teeth? Piece of cake. They'll bond a paired, natural-looking set right in, and you'll be biting into food far more substantial than cake in hours.
But even more impressive is what's going on inside an R2-D2 look-alike on the floor in front of you. If you need a "restoration"—replacement of tooth structure with a cast filling, which is either an inlay that replaces part of a tooth or a crown that covers an entire tooth—this is the space-age ticket. Called Cerec, it's German-engineered and has a laser scanner that outlines and preserves the genetic design of one of your teeth with pixel precision, and does it better than the conventional method of pressing a soft, gooey molding material over the tooth. It calculates the tooth's exact dimensions, converts the information to radio signals, and sends them to a milling unit in the next room, where in minutes diamond burs transform a tiny block of ceramic—colored to match the enamel of your other teeth—into, say, a natural-looking crown. No need for an awkward, bulky temporary that might have to stay in place for weeks. After being test-fitted and color-adjusted, the new restoration is bonded into place, and the result is a cosmetically appealing restored tooth that has 103 percent of its original strength, with nary a sign that it is a technological fake. Including checking your bite and fit, it is all done in one visit, from start to cement, as opposed to the series of dental appointments required for traditional crown work plus the time it takes to get a fabrication from a dental lab.
Welcome to the brave new world of high-tech restoration dentistry, where even those who fear going to the dentist come willingly, where the dentists roll their eyes in disbelief when you mention extractions, and where, above all, inlays, onlays, gum architecture, and, ultimately, the smile rule. Here, teeth are bleached up to nine shades whiter in a single sitting, and crowned and laminated in a mere 24 hours. Gum tissue is vaporized bloodlessly in a few minutes with lasers—their power to cut through steel and bore holes in diamonds tamed, their versatility harnessed to speed the process of bleaching teeth and even detect incipient lesions that elude usual examination methods. Here, too, dental implants are deftly fused to the jawbone to serve as a stable support for artificial teeth, making for a more comfortable mouth than is often the case with removable dentures. And on the horizon, something that may make even the technology-minded dentist subservient to a new breed of bio-dentists—tissue-engineering techniques that will repair damaged teeth with natural materials and actually grow new teeth to replace lost ones. "Eventually we'll go to genetic dentistry," says Dr. Stuart Ross, the former president of the Academy of Computerized Dentistry in Washington, D.C. "We are progressing towards a more conservative aesthetic, less invasive dentistry. Ultimately, we hope to use genetic coding to both prevent and repair dental disease."
Indeed, it appears that the public, which under other circumstances regards a trip to the dentist as a visit to a house of pain where time passes at an excruciating snail's pace, does want at least some forms of dentistry: the sort that will attract admiring glances and, it is hoped, raise one's self-esteem. "The effort to meet this need has become a multibillion-dollar industry," says Dr. Ronald E. Goldstein, clinical professor of oral rehabilitation at the Medical College of Georgia's School of Dentistry, "and is fueled increasingly by the desire for whiter, brighter, younger-looking smiles." He points out, too, that people are living longer, and this aging population has an increasing number of natural teeth. "The physical and aesthetic attributes of aged teeth are identifiable," Goldstein adds, "and over time alter the appearance of both teeth and smile."
In a sense, even though restorative dentistry has a history that goes back at least to the 15th-century surgeon Giovanni Arcolani, who filled teeth with gold leaf, it is a new art, one that is now increasingly in vogue throughout the nation. On hundreds of Web sites advertising a "caring" attitude and "relaxed atmosphere," and with clients eager to give a workout to all those muscles that make a smile, the restoration practice has accomplished what generations of dentists could only dream of: getting people without a toothache to come to them. "People want to go to the dentist now," says Dr. Ross. "They want to preserve the assets Mother Nature gave them."
Fast-paced businesses, cosmetic dental practices can skillfully restore beauty to molars stained by coffee, tea, and tobacco, as well as function and strength to those that are chipped, out of alignment, crowded, cracked, and just plain gone. Compared to getting a nose job or a tummy tuck, or any other aesthetic procedure that makes people feel good about themselves but requires surgery and lengthy healing, cosmetic dentistry is walk-in, walk-out stuff, something you can often do over a lunch hour. And the vast majority of patients leave satisfied. "We frequently see patients who, when we first meet them, haven't smiled in years," exults Dr. Robert Maher of the El Paseo Center for Cosmetic Dentistry in Palm Desert, California. "But they are beaming from ear to ear when their treatment is completed."
On a recent visit to one highly regarded practice, New York's Thirty-Third and Third Dental Associates, we watched Dr. Michael Iott, a whirling dervish of modern dentistry, go into almost single-handed makeover mode on what he called "an easy day": In three hours he bleached a set of teeth, performed laser surgery on a receding gum line and sent the patient out in time for lunch, placed two shining veneers on another, installed a difficult and unusual bridge to replace a young man's front tooth that had been missing for years because no one else could figure out how best to do the job, and did a Cerec-driven restoration. Taking a break from his instant instrument sterilizers—from spectrocams that do instant color analysis for perfect shade matching in restored teeth to intra-oral cameras, plasma arc-lamps that set the glue for veneers, and all the various mixtures essential to what is now known as adhesive dentistry—Iott says, "When I got into dentistry twenty years ago I was not interested in advanced technology. Now I've got a reputation, I'm willing to try anything that is scientifically proven, and when I see patient satisfaction, time saved, and great results I say, 'How can you not do it this way?'"
One reason not to might be the cost to the dentist and the special training that's required. Not every dentist can afford the $90,000 for a Cerec system, or even some of the other leading-edge technologies, and many don't have the patient volume necessary to amortize the cost. "It's true that a lot of dentists aren't using these technologies," says Dr. Ross. "They're a big investment and require that dentists reconsider how they want to practice, especially when patients don't need second appointments."
There's also the cost to the patient, especially with most of these procedures, which are not covered by dental insurers. Happy to pay for preventive care, insurers feel that patients should put their money where their mouths are when they just want to light up a room with a beaming smile. In his satiric 1906 lexicon, The Devil's Dictionary, poet-journalist Ambrose Bierce defined a dentist as a "prestidigitator who, putting metal in your mouth, pulls coins out of your pocket." But Bierce was addressing another century, and metal in the mouth is fast giving way to composites and other materials that many dentists and patients prefer to the conventional silver-mercury amalgams. Also, Bierce's observation implies that dentists get paid for easy work. Cosmetic dentistry—and indeed all dentistry, especially the demanding specialties of endodontics, periodontics, and prosthodontics—isn't easy, and it isn't cheap, especially implants, which involve surgery beneath the gums and regular dental visits. But fees, after all, are a fact of life—medical, dental, or otherwise. As the Greek lyric poet Pindar put it, "Alas, even the lore of leech-craft is enthralled by the love of gain." Prices vary by dentist and region, but a typical bleach that takes an hour costs around $600 ($750 for an hour and twenty minutes); a veneer is around $850 per tooth (more if it's a rush job); a computer-generated inlay, a cast filling that replaces part of a tooth, runs from $500 to $900, depending on the number of surfaces; a crown, $1,050; laser surgery, about $1,000; and an implant, $2,000, plus the cost of the crown or crowns.
Is it worth it? The American Dental Association (ADA) hints at an answer in one of its brochures: "Your smile can be the most eye-catching feature of your face and even the most subtle change in your smile can make a dramatic difference in the way you look and feel about yourself." Since a smile makeover is not something one does every day, those who opt for it view the cost as a long-term investment. A handsome smile, after all, is as essential to a CEO's or a salesman's image as the cut of his clothes and state of his hair. Dentists and denture makers undergo these procedures themselves, too: They need to put their best teeth forward when seeing clients. The smile wizards also know that what they achieve in a patient's mouth can give them a walking advertisement—or, as one less self-effacing practitioner put it, "a signature, like Renoir on a painting."
So, considering that a smile makeover, just like hair-grafting or a hairpiece, can change one's entire outlook on life, the best advice is to forget the cost if you are able to and take the plunge. It might well work more wonders than a churchful of saints. But there are a few cautions, chief among them that cosmetic dentistry does not prevent or cure either oral infections or disease, both of which can adversely affect not only the mouth but the body as well. According to Dr. Marjorie Jeffcoat, professor and chairperson of the department of periodontics at the University of Alabama at Birmingham and one of the ADA's expert spokespersons on gum diseases, infections that cause oral disease may make patients more prone to cardiovascular disease and stroke. Conversely, certain systemic diseases can affect oral health, and some medicines that control high blood pressure can cause gums to swell and bleed when one brushes or flosses. "We are learning more about these associations," Dr. Jeffcoat explains, "and we are turning the equation around. When we treat periodontal diseases and keep the mouth clear of infections, we may also be reducing the risk for other systemic ailments."
Thus, a new row of sparkling teeth— whether bleached, veneered, crowned, or implanted—is a waste of time and money if your gums are not healthy or if your jawbone structure can't support the work being done. Nor are all of the procedures recommended across the board.
"In fact," says Dr. Iott, "I find I have to talk some people out of dental work. They might decide they want a veneer, and they figure that the guys who advertise will always do it. But I wouldn't do one just to cover something up. That's a lot of dentistry to accomplish what a simple bleaching can often do."
Veneers, Bonding, and Enamel Shaping
The basic concept of dental veneers can be compared with carpentry, where a piece of inferior wood is covered with a thin layer of something finer. In dentistry, veneers take the form of tooth-colored thin shells made from models of one's teeth and fabricated of porcelain, which is made from a very strong glass. Generally used to cover the front side of front teeth, the thinly sliced facings are used to camouflage gaps and treat teeth that are permanently stained, badly shaped, crooked, chipped, or eroded at the gum line. Usually, to accommodate the thickness of the facing, a small amount of tooth enamel must first be removed.
Bonding treats the same conditions as veneers and is also used to protect exposed tooth roots resulting from gum recession and to fill small cavities. It involves first etching the tooth's enamel with a solution, a process that enables a composite material to better attach, or bond. Different-colored resins are blended to match the existing tooth and are then applied, contoured, hardened under a special light, and finally smoothed and polished.
Frequently combined with bonding, enamel shaping contours natural teeth that have grown crowded or uneven and corrects eyeteeth that appear too long. A generally quick and painless procedure, it involves removing or contouring the body's hardest substance, enamel. Dentists are aware that this technique has to be approached cautiously, since enamel is irreplaceable.
You'll never get anywhere near the results that this procedure achieves by brushing at home with an expensive extra-whitening toothpaste. Teeth yellow with age or are discolored, darkened, and stained by what we eat, drink, and smoke, and it takes industrial-strength treatment to bring them back—or to make them look better than even Mother Nature intended. There are two approaches to bleaching: chairside, in the dentist's office, and a home-use bleaching system dispensed by the dentist. In the office an oxidizing agent, usually hydrogen peroxide, is painted onto the teeth, after which a special light that helps activate the bleaching agent is focused, usually at five-minute intervals, on the teeth. For home use the dentist fabricates a mouth guard that holds a bleaching gel and is worn up to two hours daily for about two weeks. According to the ADA, people with gum recession and certain dental conditions may not be good candidates for this type of bleaching. Moreover, once bleached, the teeth—which become slightly sensitive following the procedure—should be cleaned and flossed twice daily; the dentist should also be seen for regular professional cleanings and sometimes touch-up treatments. It's also important to remember that tobacco, coffee, tea, berries, and red wine can restain the surface of the teeth, and these should be avoided, at least for the first few days after the procedure.
Remember them? Well, they've been around for more than 2,000 years and are still in countless mouths despite the jokes they've had to suffer. They replace all or some natural teeth and provide support for cheeks and lips as well. Ranging in price from $800 to several thousand dollars for a full upper or lower set, they're cheaper, safer, and less stressful than installing a full set of implants and crowns. Moreover, where it was easy to identify falsies in someone's mouth years ago, today's dentures are made with new materials to match facial profile and natural teeth so little change in the wearer's appearance is noticeable.
No matter what anyone tells you, dentures take some getting used to, and eating with them takes practice and a progression from soft foods and small pieces to a more normal diet. They don't require an adhesive because they're custom-manufactured to fit, but they can feel loose until tongue and cheek muscles accommodate, and temporary irritation and soreness are not uncommon. Until you get the hang of them, dentures may also "click" when you're talking, and sometimes slip when you laugh, cough—or try to flash that new smile you're so proud of. You may also have to remove them before going to bed.
These are posts or frames—usually made of tissue-compatible titanium—that are attached surgically beneath the gums and to the jawbone as substitutes for natural tooth roots. They serve as supports for a single crown or for replacement artificial teeth grouped on a bridge or denture. With thousands of these underpinnings set in place every year, they have become a fairly popular alternative to conventional dentures: Anchored in the jawbone, the teeth they carry won't slip or shift in the mouth, like dentures might, and eating and speaking are accomplished without trepidation. For people who have lost teeth through accident or disease, they may be a good option, but for routine smile enhancement they could be rather drastic, considering the other choices. Implantation is also not one of the dental specialties recognized by the ADA, but the implants are, and should be, placed only by dentists or specialists who have had training in the procedure and have performed it over and over.
The surgery itself is time-consuming and not without risks, but the ADA considers two kinds of implants safe. With an endosteal implant, the device extends into the jawbone, which requires sufficient bone to support the implant. Gum tissue may have to be stitched over the implant for three to six months, during which time the bone, along with collagen fibers (protein that makes up the body's connective tissue) begins to surround the implant, finally attaching to the metal. More surgery is then required to attach a post to the implant, and then the artificial tooth to the post.
An alternative technique, a subperiosteal implant, is employed when bone is lacking. This is a metal frame that fits on the jawbone under the gums; posts attached to the frame protrude through the gums. As the gums heal, the frame becomes fixed to the jaw, and as with the endosteal implant, crowns are mounted on the posts. Infection is always a possibility with implants, as is jawbone deterioration from increased stress on the bone. Certain chronic diseases—among them osteoporosis, diabetes, and sinus problems—can interfere with healing, and even prevent the bone and implant from melding. Smoking may also affect the implant's stability over time, and patients must commit themselves to meticulous oral hygiene and regular dental visits. Only a dentist familiar with your oral and overall health history should advise you as to whether this choice is for you.
Synonymous with braces, this specialized branch of dentistry corrects malocclusion—the improper alignment of biting or chewing surfaces of upper and lower teeth—and is performed on adults as well as children. Most cases of "bad bite" are inherited, although accidents, sucking of the thumb or fingers, and early and late loss of baby teeth can bring it on. Treatment is tailored to the individual mouth, and today's braces are less noticeable than they used to be. The brackets, which hold the wires and can be put on the back of the teeth, may be made of metal or a transparent or tooth-colored material. The wires are also made of space-age materials that exert steady but gentle pressure on the teeth, which speeds up the tooth-moving required and does it more comfortably. Average treatment time is around 24 months, but in adults it takes longer, since an adult's facial bones are no longer growing.
These are dental restorations (usually of alloys, ceramic, or porcelain) that cover, or "cap," a damaged, discolored, or misshapen tooth, strengthening it and improving its appearance. They may also be recommended to replace a large filling when not much tooth is left; protect a weak tooth from fracturing; attach a bridge and cover a dental implant; or cover a tooth that has had a root canal. (In the latter, diseased tissue inside the tooth that contains nerves and blood and lymph vessels is removed. The canal is filled with a permanent sealant, and an embedded post may be needed to hold the crown if the tooth cannot be saved.) Preparing and setting a crown is not as simple as it sounds, but computer modeling and fabrication have cut the time involved. It can still require a couple of visits if done "the old-fashioned way," and even additional visits for adjustments. Computer-assisted or not, the location of the tooth to be capped has to be considered, the amount showing when you smile, the tooth's function, and the position of surrounding tissue. The outer portion of the tooth has to be shaped to accommodate the crown's thickness, and an impression (or a computer model) has to be made. In the multiple-visit technique, a temporary crown of acrylic resin covers the prepared tooth while a permanent crown is made. When that's done, it replaces the temporary crown, and minor adjustments give you a comfortable bite.
For over a century, amalgams of silver, mercury, and other materials have been used in tooth restorations worldwide. Mercury is necessary in the mix because it binds the metals and makes the material easy to work with. It's also what makes the liquid paste solidify as it sets. Despite periodic unsubstantiated claims that question the safety of these amalgams, the ADA maintains that fewer than 100 cases of an allergic reaction have been reported, and that they continue to be safe, a view shared by the U. S. Public Health Service.
But with cosmetic and other considerations, tooth-colored filling materials, usually composite resins, are often preferred by patients. Generally more expensive than amalgams, they are ideal for front teeth, where a natural appearance is desired, but can be used on the back teeth, depending on the extent of decay. One type, a resin ionomer that seals the tooth and also releases fluoride, is most suited for children, for filling decayed baby teeth, and for treating root decay in older adults. According to a recent report by Dr. Alan A. Boghosian, director of clinical research of biological materials at Northwestern University Dental School in Chicago, when one resin ionomer was tested in a five-year study at the university, it demonstrated a 100 percent effectiveness for adhesiveness and retention. "A tooth that's treated with this material may be more resistant to decay coming back," Dr. Boghosian reported.
As impressive as these procedures and treatments are, they may become obsolete one day. If, as Cervantes observed in Don Quixote, "every tooth in a man's head is more valuable than a diamond," it would seem wise to hang on to as many as possible. We can often do that through good oral hygiene, but there's an ideal way, one not yet within our grasp: coaxing our teeth to self-regenerate so that we won't need all those dentures, implants, veneers, and crowns. It's not such a far-fetched idea. At the University of Texas Health Science Center at San Antonio, Dr. Mary MacDougall, associate dean for research at the dental school, has been looking into the dynamics of tooth formation with an eye to eventually growing human teeth.
It starts at the cellular level, where the unique, hard, mineralized tissues of the tooth (dentin, enamel, and cementum) are produced. In Dr. MacDougall's laboratory experiments, genetically engineered mouse and human cell lines were made to reproduce and form tooth tissue. "We are also using these cell lines to study the mechanisms that dictate and control tooth-specific genes," she explains. "Moreover, whole-tooth tissue cultures have been established to grow mice 'teeth in a dish.' Ultimately, we expect to regenerate teeth in culture as replacements for the next-generation dental implant, or even get additional teeth to grow at the site." If it works, the advantages are obvious. But there might be a small price to pay if the latter part of Dr. MacDougall's prediction comes to pass: Adults would have to learn, once again, how to use a teething ring.
John Langone took a critical look at current treatments for baldness in the May/June 2000 Departures.