The question: Do we really need costly "dental systems" and computerized toothbrushes to keep teeth and gums on the cutting edge?

The answer: Probably not.

The experts: Dr. Andrew Greenberger, periodontist and dental consultant for Delta Dental of New Jersey. Janet Jaccarino, registered dental hygienist and assistant professor at the School of Health Related Professions at the University of Medicine and Dentistry of New Jersey.

"You just need to brush twice a day and floss at least once," Greenberger said. This is worth emphasizing now, as May is designated National Smile Month.

Greenberger is dismissive of the dizzying array of toothbrush choices on the market. "A toothbrush is a toothbrush is a toothbrush," he said.

This much he'll concede: Oral-care gadgets are useful where an ordinary brush won't do the trick.

For example, an electric or battery-operated brush can be a good motivator for kids. It may reach areas that the less-than-diligent neglect. And it's useful for people with arthritis or for caregivers of the elderly or disabled.

Options range from battery-operated models such as Pulsar or SpinBrush (about $6) to fancy rechargeables such as SynchroSonic Advanced Action Sonic Plaque Remover ($69.99).

You still have to position and maneuver these brushes correctly, because the bacterial film on teeth can't magically be vibrated away.

Brushes with built-in timers remind the user that it takes a good two minutes to do the job right. (That's two minutes for each of the four sections of the mouth, Jaccarino maintains.)

The rechargeable Oral-B Triumph ($179.99) has a computerized digital display that also signals users when to change the head.

"That's great, because some people will use the same toothbrush forever," Greenberger said.

A cheaper alternative: Get a new toothbrush every three months, or when the bristles start to splay. Some manual brushes have colored bristles; when the color begins to fade, replace it.

In the meantime, keep your brush as germ-free as possible by rinsing it with water and storing it where it can dry out.

Some electric brushes include a prefilled toothpaste cartridge, like the Sonicare IntelliClean System ($139.99). Greenberger said it's a good idea not to swipe paste off the same tube with different brushes — that spreads bacteria — but he's wary of products that need branded refills.

He also reminded us that toothpaste is more for whitening and freshening than cleaning. The action of the brush — not the paste — cleanses the mouth.

Jaccarino said not to buy any special oral-care product unless your dental professional has suggested it and shown you how to use it.

"They're all designed to work best if the patient is in good oral health, so first you have to be at that stage," she said, adding that as many as 95 percent of Americans have some form of gum disease.

Misusing any dental tool can do more harm than good, she said. A scaler or pick in amateur hands, for instance, easily damages gums and invites infection. Don't buy these instruments at the drugstore unless you're trained to use them.

For animated instructions on how to brush and floss properly, see: ada.org/public/games/animation/index.asp.

The Flosbrush is great for carrying around in a pocket or a purse; the Oral-B Hummingbird flosser gets at hard-to-reach areas.If you're not flossing before or after brushing, you're missing 30 percent of your tooth surfaces. Yet even though 50 yards of dental floss costs about $2.99, only 49 percent of Americans bother to use it.So if one of the flossing gizmos on the market will motivate you to clean between each tooth — or if you must floss one-handed — go for it, the experts said.Remember that you're aiming to remove the transparent film of bacteria between teeth, not just food particles. It's still working if you don't see anything on the floss.The battery-operated Oral-B Hummingbird flosser (about $8) is angled to get into hard-to-reach areas. Press a button once the floss is in position, and it starts a mild vibrating mechanism. Not that vibration takes off plaque; that requires scraping.The Waterpik flosser (about $19) uses flexible vibrating picks. They're not easy to fit between tightly spaced teeth or back teeth. Like the Hummingbird, our experts told us, it's better than nothing but not as effective as manual flossing.The Reach Access Daily Flosser (about $3) resembles a toothbrush handle onto which you snap disposable floss heads. Made for children 6 and older, it's easy to use and can scrape between teeth fairly effectively. Still, it's not as flexible as a plain length of floss.Hand-held disposables like GUM's Eez-Thru (less than $2 for 40) and Flosbrush (about $4, 100 uses) are great for carrying around in a pocket or purse.It's best to get instructions from a dental professional to assure you're doing an effective job without injuring your gums.

The mouth is the portal to the entire body, so keeping it clean and healthy affects your general well-being. What do you need to do the job right?Must-haves:• Toothbrush. Any kind with soft, rounded bristles can effectively remove plaque (aka biofilm), the bacteria that can calcify into hard-to-remove tartar.If you prefer an electric model, choose one with a small rotating head.For brushing on the go, carry disposable tooth wipes or sterile gauze. This is a good cleansing alternative for babies and hospital or nursing home patients as well.• Dental floss. Thin, unwaxed floss is better because wax can leave a bacteria-attracting residue on teeth. Use it at least once a day. If you have trouble using unwaxed floss, use a thin Gore-Tex type.• Tongue scraper. For less than $4, you can get a spoon-shaped or horseshoe-shaped manual model that removes bad-breath-causing bacteria from the back of the tongue.There are battery-operated models like the Oralgiene tongue cleaner ($20). The manual Reach Max toothbrush has a tongue cleaner on the reverse side of the brush head.Whichever you choose, bring it along on your next dental visit to make sure you're using it correctly.When recommended:• Interproximal cleaner (aka proxy brush or end-tufted toothbrush). These gizmos look like bottle brushes and are designed to clean plaque from teeth with larger spaces between them, where floss is not effective.• Rubber-tip or wooden gum stimulators. Used correctly around the tooth surface, these low-tech gadgets bring blood to the gum tissue, helping get rid of existing bacteria and firming the gums to better resist incoming germs.