Goodbye to the lab-coated nerd; welcome the dentist as hip celebrity. Ouch!

Framed in the waiting room of Drs. Marc Lowenberg and Gregg Lituchy is a New York magazine cover, with their photograph, touting a listing of "The 100 Best Dentists in New York." It's a fake, a spy magazine parody from 1991, when the idea of celebrating dentists still seemed ridiculous.

"Because who would care?" Dr. Lowenberg said. He and his partner show off the cover at their Central Park South practice as a reminder of how far their profession has come in the last eight years.

Now, people do care about dentists, especially cosmetic dentists, who promise yet another form of makeover by whitening, straightening or substituting inferior teeth with million-dollar — or at least $20,000 — smiles.

This booming business has made its most skilled, or best-known, practitioners not only rich, with incomes up to seven figures, but quasi-famous. The old stereotype of the dentist as bland, lab-coated nerd has been elbowed aside by an aggressively mediagenic new breed eager to do some image polishing.

Like plastic surgeons of a certain class, these power dentists hobnob with their celebrity patients, partying with Donald Trump, dining with Norman Mailer. They show up in gossip columns and hire publicity agents to promote their high-tech gum lasers and state-of-the-art laminating techniques — even sending out Hollywood-style head shots of themselves to advertise their star quality. Gone is the sterile house of pain that used to be identified with dental offices. The newly hip and patient-sensitive dentist operates in opulent surroundings, with an attractive staff trained to deliver concierge services like cappuccino and massage.

"With some of them, it's more about the publicity and trying to elbow their way into high society and get invited to openings," said Dr. Richard Rashbaum, a New York dentist who doesn't consider himself in the dental fast lane.

Dr. Timothy Rose, president of the American Dental Association, said the drop in the decay rate among America's fluoridated generation had given dentists time to focus on esthetics, as had the demand by aging boomers for "the bionic body."

"Most dentists now practice some phase of cosmetic dentistry," he added.

A 1997 survey in the Journal of American Dental Association found that 84 percent of dentists offered tooth whitening, a once-exotic procedure. Membership in the American Academy of Cosmetic Dentistry, a professional group, has doubled in five years, to 4,000.

Improved technology has expanded services from what dentists call the routine of "drill, fill and bill." Lasers can alter gum lines without sutures, or bleach yellowing teeth almost instantly. Chipped, crooked or just plain bad teeth can be concealed with fingernail-thin porcelain veneers. In the world of bionic beauty, the "smile lift" has become as familiar as the face lift. Traders in cocktail-party confidences can score points by announcing, "Larry did my teeth," referring to Dr. Larry Rosenthal, whose patients include Donald Trump, Kathie Lee Gifford and a long roster of socialites.

Dr. Rose said, "The guys who focus on discretionary services have a little bit of that old salesman-type thing, to tell people why they have to do it."

And do they ever. Seminars in "practice management" for business-minded dentists can include such nonmedical recommendations as: When presenting a patient with a treatment program, always use a Montblanc pen.

"It's no longer enough to have published in the journals," said Dr. Jeff Golub-Evans, a New York dentist and frequent contributor to professional journals. "Now people want to know if you've been on 'The View.'" Or they want to know that Dr. Golub-Evans has ministered to the marquee mouths of Regis Philbin and Wayne Newton.

Dr. Irwin Smigel, president of the American Society for Dental Aesthetics and, after 40 years in practice, a dean in the field, is skeptical of his high-flying colleagues.

The high-end New York dentists — not the (800) NU TEETH guys on the subway — share several uncanny similarities. They tend to come from blue-collar backgrounds. Many are ex-musicians and share a vision of the dentist as artist. Their own fake teeth always look amazingly real.

But each has a unique style. And even a selective sampling reveals a distinct typology.

The Smile Lifter

"I'm not God," Dr. Rosenthal said. "I'm only a dentist."

Some of his patients might disagree, with the "only" part anyway. Dr. Rosenthal's same-day, $15,000 smile lift has attracted chief executives, socialites and models and generated a puff piece in last November's Vogue hyped with the cover line, "Smile! How to Buy Cover-Girl Teeth." Another telling detail of Dr. Rosenthal's résumé is that he once worked as a lounge piano player on a cruise ship.

He seems congenitally up. His motivational patter is nonstop, a live infomercial. Imagine a kinetic cross between Michael Douglas and Tony Robbins. "People ask me, 'Larry, when do you rest?'" hesaid. "I say, 'When I'm preparing teeth and reshaping them!'"

According to the New York State division of professional licensing, Dr. Rosenthal's dental license was suspended for six months in 1987, although the agency would not reveal the reason. Dr. Rosenthal explained that he had been charged with a misuse of prescription forms to obtain sleeping and diet pills, but he maintained that the forms had been stolen and used by someone else.

Dr. Rosenthal and his family spent last Easter in Palm Beach, Fla., as guests at Mr. Trump's Mar-a-Lago resort. His 50th-birthday party in the Hamptons last summer drew a guest list of patients sufficiently notable for an item in The New York Post: Mr. Trump, Kathie Lee and Frank Gifford, and Sandy Korn Taylor (a former Penthouse Pet).

But as for all celebrity dentists, it is the nonfamous who keep Dr. Rosenthal in $40,000 laser machines. Enid Goodman, a nonfamous prospective patient, from Bloomfield Hills, Mich., had come for a consultation in his wood-paneled office on East 76th Street after reading the Vogue article. "I checked out some people in my area, but they didn't seem as good," she said, flattening her vowels like rivets on an assembly line. Ms. Goodman had had plastic surgery six weeks earlier — "so my face is kind of lopsided" — and said she now wanted a "brighter smile," adding, "But I don't want to leave looking like Jim Carrey!"

Unlikely. Dr. Rosenthal has built his reputation on natural-looking porcelain veneers that can cost up to $2,000 apiece, almost double the fee of a nonbrand-name dentist. His patients do not get the blinding, uniform laminates derisively known in the trade as Chiclets. Later this year, he plans to roll out a consumer product line bearing his name, including an electronic toothbrush and dental floss that he said would remove stains between teeth.

"Did the Beatles know they were the Beatles?" he asked, pondering his legacy. "Did Muhammad Ali know he was Muhammad Ali? I'm not saying I'm in that league, but..."

The Players

"Celebrities are as nice, if not nicer, than average people," Dr. Lowenberg said in the small private office he shares with Dr. Lituchy. The office is decorated in a style that could be called early Carnegie Deli. Floor-to-ceiling celebrity glossies are autographed with fulsome sentiments of thanks and praise.

"I love going to him so much," said Courtney Cox, who first went to Dr. Lowenberg when she was nobody and he was "just this young hip guy" willing to put her on a payment plan.

Julianna Margulies found him in the Yellow Pages when she was a 21-year-old waitress with a badly replaced front tooth.

"I went to two dentists who said we'd have to give you six new teeth," Ms. Margulies said. "Marc said, 'Just some tweaking, and we'll make it match.'" She still flies from Los Angeles to New York for checkups.

"I've known a great many dentists over 75 years," Mr. Mailer said. "And I don't remember ever looking forward to seeing any of them."

Show business people seem almost to regard Dr. Lowenberg as one of their own. Four years ago, a patient who is a producer suggested that Dr. Lowenberg try directing a play. "It was about a man and a woman picking each other up in a bar," Dr. Lowenberg recalled. It was staged way off Broadway, and though hardly a critical or a commercial coup, the experience clarified his true calling. "When I had the choice of being a director and being a dentist," he said, "I knew I would never direct again."

The low-key Dr. Lituchy came to work for Dr. Lowenberg as a Columbia University dental student and still seems slightly awed by his charismatic mentor.

"He's a brilliant businessman," Dr. Lituchy, 40, said of Dr. Lowenberg, 52, noting his idea to hire a masseur to rub anxious patients' shoulders in the waiting room, or to massage their feet as they recline in the chair.

Dr. Lowenberg estimates that half his mid-six-figure income from his thousands of patients comes from what he calls smile makeovers.

In the 1970's, a friend of his who is a physician and who treated the Rolling Stones sent Ron Wood and Keith Richards his way. He has been treating dentally underprivileged celebrities ever since.

Ann Marie Cseh, a Hungarian model, provided the startling before-and-after shots gracing the outside of the Lowenberg-Lituchy press kit and video. Eastern Europeans have supplied an influx of candidates for their services, as have rap and hip-hop stars, many of them sent by the music impresario Russell Simmons, himself a patient of Dr. Lowenberg. On the wall of fame is a signed, framed cover of the February issue of Vibe, featuring Foxy Brown, a rap star.

"Half my practice is in this magazine and I have no idea who these people are," Dr. Lowenberg exclaimed, sounding stunned that famous people exist who are unknown to him.

Sy Presten, the practice's press agent, turns some of those famous names into gossip items. But such is the status of the celebrity dentist that details of Dr. Lowenberg's personal life made the papers when, a year ago, he started dating a patient, Joan Finkelstein, a former owner of the New York Law Review.

How did he like reading about his romance in Page Six? "Initially, I was embarrassed," he said. "But you get used to it."

Not in name only is Dr. Golub-Evans a hyphenate. Two business cards sit on his receptionist's desk. One reads, "Jeff Golub-Evans, D.D.S." The other is for "Jeff Golub-Evans/Mixed Media Artists."

The white exposed brick walls of his airy brownstone on East 71st Street are decorated with art (his own) and giant, blown-up magazine covers of Paulina Porizkova, a model patient.

Indicating one of his woodcuts, he said, "A bunch of these are in a museum of Bali." He taught dentistry on the island last year.

Wearing a brown turtleneck, blue wool pinstripe pants and Doc Martens, he could be a hip, well-paid college professor. Or a more respectable Lou Reed, with his wary gaze, quietly intense manner and New York-inflected drone.

Like many of his generation, Dr. Golub-Evans, 55, hoped dental school would help keep him out of Vietnam, he said. It didn't. Having joined the reserves in 1966 after finishing dental school, on the bad advice that reservists wouldn't be called up, he was sent to Vietnam anyway.

Dr. Golub-Evans figures he has done 30,000 porcelain veneers. He calls the people he treats clients rather than patients, "because they're not sick," he said, adding, "This is the era of the designer dentist and dental salons."

As a dentist-artist, he can also paint a broader, mega-picture of his trade.

"We make celebrity smiles, and other people then want to reproduce those smiles," he said. "We create the illusion of beauty, rather than the reality."