Updated

In today’s world of “extreme makeovers” and Hollywood picture-perfect-everything overload, one trend to pretty up the mouth is having an adverse effect on the eyes.

Exceedingly bright, white teeth have become so common — and often so blinding — that people who undergo the bleaching and porcelain veneer procedures behind them should be required to hand out sunglasses before flashing a smile.

Pop star Hilary Duff recently got porcelain veneers to go over at least four chipped front teeth, her rep told Star magazine. Star-gazers have been able to tell — and they don’t think the job looks too natural.

Michael Douglas also had a similarly less-than-subtle procedure, according to Beverly Hills cosmetic dentist Dr. Kevin Frawley. And other celebs including Jon Bon Jovi, Oprah Winfrey, Brad Pitt, Angelina Jolie, Jessica Simpson, Nick Lachey, Britney Spears, Cheryl Hines, Eva Longoria and Tom Cruise — plus many more — have gleaming white smiles, probably as a result of excessive bleaching or in some cases, cosmetic dentistry.

“It looks ridiculously unnatural up close, but Hollywood is the place where fakeness is celebrated,” said Tom O’Neil, senior editor at In Touch Weekly. “It’s another example of extreme mouth makeovers. … Now you have a completely fake smile: pillow lips, bleached teeth and veneers.”

TV journalists have also jumped on the toothpaste-smile bandwagon. Many anchors and reporters have especially noticeable chompers when they grin on camera.

“There should be a compromise between having good, clean teeth for television and not looking freakish,” O’Neil said. “But they take it to an extreme.”

Bleaching can be done using over-the-counter treatments like Crest Whitestrips and other remedies with relatively low dosages of peroxide. It can also be done professionally in the dentist's chair using light- or laser-assisted procedures with higher-concentration peroxide gel — or by making molds of the teeth and sending them home with the patient to fill with the gel and wear over several days.

The national average dentists will charge is between $400 and $700 for whitening, according to Frawley.

Getting porcelain veneers is a more intensive procedure. Molds are made of the teeth, which are then filed down and fitted individually with the porcelain shells, which go around the outside of the teeth.

Generally, veneers are used when patients have spaces or crooked, chipped or small teeth. They're the updated version of the crown, which goes over the whole tooth and requires more reduction of the original.

Patients wear temporary veneers at first to get used to them while the permanent ones are made, then go back to get the real ones. The treatment can cost between $1,500 and $2,000 if it involves a lot of visible teeth, but can go as high as $6,000.

It’s not just the sparkly stars and glitzy TV personalities who are plunging into the bleach and piling on the porcelain. The general public is swimming around in the sea of cosmetically altered, snow-white smiles too.

"It's a very big part of my practice in a small town in Minnesota," said Dr. Kimberly Harms, a dentist and co-owner of River's Edge Dental Clinic in Farmington, Minn. "And it's growing. We live in a country where nice smiles are valued."

Farmington is a town of 10,000; the clinic she runs with her husband has about 4,000 patients. She said veneers and other restorative and cosmetic procedures are especially popular among baby boomers, who didn't have preventive measures like braces or fluoride in drinking water and toothpaste the way younger generations do. But they have options their parents and grandparents didn't.

"For my mother's and grandmother's generation, their teeth were in a jar by the bed. They didn't have any teeth," said Harms, who is also a spokeswoman for the American Dental Association.

The problem is, some of those with badly done veneers or crowns might as well go back to those old days of false teeth.

“They look like dentures,” O’Neil said. “Even though they get the best Beverly Hills orthodontist, it still looks like they bought their teeth at Kmart.”

Series like ABC’s "Extreme Makeover," which will return to air in the form of specials later this season, have had sway. Not only has the reality show helped make the term “porcelain veneers” a household expression, it's raised awareness among the general public about cosmetic dentistry procedures and plastic surgery.

"I think it's played a big role," said "EM" producer Janis Biewend, who was inspired by the show to get veneers and is pleased as punch (minus the stains) with the results.

"When I first started, I didn't know anything about veneers or Zoom! whitening. It was all news to me. It's a much more common denominator now."

The reality program chooses two ordinary people per episode to undergo intensive, dramatic makeovers — involving everything from multiple plastic surgeries and liposuction to dental work — and then unveils their new looks.

"That show has really opened a lot of people's eyes, no doubt about it," Frawley said. "As far as the dental impact of 'Extreme Makeover,' it's had a huge effect."

A "Friends" episode even poked fun at the blinding bleach trend: Ross goes overboard with an at-home dental whitener for a hot date that ends when she turns out the lights and his smile glows in the dark.

Some veneer recipients, however, weren't influenced by Hollywood stars, reality shows or sitcoms, but by their own dentists. One of Harms' patients, trucker Tim Clemmer, got the idea from a video about the procedure that was playing while he waited for a checkup in the dental chair.

After he had his 12 veneers put on and paid the $6,000 fee, the 37-year-old, Lakeville, Minn., man said he was thrilled. Before the procedure, Clemmer had a big gap between his two front teeth, which were too small, and smiled with his mouth closed to hide the imperfections, he said.

"I walked out the door the happiest man in the world. It changed my whole life. I can't even tell you what it did for my love life," said Clemmer, who now has a girlfriend. "I had a big confidence problem due to my teeth. Mentally, it changed me. Now I don't have that confidence problem and the embarrassment."

And luckily, according to Clemmer, his veneers look natural — not too white or perfect but suitable for his face.

Some reports have emerged about the possible risks of the whitening and veneer treatments, though the ADA and dentists say there isn't enough evidence showing the processes are harmful.

Bleaching causes some temporary sensitivity in the teeth that goes away, according Frawley and the ADA's Harms. And gums need to be well-protected during the professional whitening jobs because of the strength of the peroxide used, Frawley said.

But beware: Incessant bleaching is never good. Frawley pointed to one study that found a mild link between over-whitening and oral cancer on the floor of the mouth that hasn't definitively been proven but has raised concerns.

"There are no long-term studies that show the enamel structure weakens or the teeth become more porous," he said of bleaching.

If veneers are done well, they shouldn't cause problems, either, according to Frawley. Sometimes a poor job results in puffiness around the gums — and like regular teeth, veneers can chip or break — but there haven't been reports of serious issues, he said.

Crowns, on the other hand, can be "damaging," said Frawley, because so much of the tooth is removed to implant them. But sometimes they're necessary for broken teeth.

Though the risks associated with improving the smile may be minimal, even cosmetic dentists agree that certain people go over the bright-white line. Harms said shades across the board have grown lighter because some people can't seem to get white enough.

But usually when a star or average Joe has noticeably fake pearly whites, it's because they are fake — at least in part, according to Frawley.

"When somebody's teeth jump out and seem like a night light in a dark room, that's porcelain veneers or crowns," he said. "The Regis Philbin Chicklet look, that opaque white that looks ridiculous, you're not going to get that with bleaching."

One mistake people make is mismatching their tooth color with their skin tones, hair and age.

There is hope. Frawley — who said about 75 percent of his patients bleach, while only about 10 to 20 percent get veneers — thinks artificially white teeth will tone down to more natural shades in time.

"The trend will get back to that," he predicted. "The pendulum has swung where everybody has these perfect, picket-fence, white teeth."

For now, we're stuck with the temporary blinding that comes along with the high-voltage smiles — whether they're on a neighbor or a movie star.

“A smile is the most important expression a star can make,” O’Neil said. “If the smile is a 200-watt smile, it’s extraordinary. It’s become a cosmetic necessity for the fancy folk. It’s now more noticeable when you meet a star up close who doesn’t have it.”