Whether dental restorations such as crowns, bridges and veneers are supported by natural teeth or implants, they require lifelong care. Newly revised guidelines recommend that patients with dental restorations visit their dentist at least every six months so that the dentist and/or hygienist can clean, adjust, repair, or replace their restorations. The dental team can also advise patients with dental restorations about home maintenance. Dental restorations made of composite materials, metal alloys, porcelain, plastic, and other manmade materials collect dental "plaque" (the sticky bacterial film that constantly forms on teeth) that must be removed with daily brushing and flossing. Otherwise, these colonies of germs will harden into tarter, compromise restorations, and threaten gum and bone health.