Brush twice a day and floss daily.

 Gum disease and tooth decay remain big problems -- and not just for older people. Three-fourths of teenagers have gums that bleed, according to the ADHA. Along with the basic advice, remember:

• Toothbrushes should be changed 3 to 4 times a year.
• Teenagers with braces may need to use special toothbrushes and other oral hygiene tools to brush their teeth. Talk to your dentist or orthodontist.
• Older people with arthritis or other problems may have trouble holding a toothbrush or using floss. Some people find it easier to use an electric toothbrush. Others simply put a bicycle grip or foam tube over the handle of a regular toothbrush to make it easier to hold.