"Here, use my toothbrush..."

Ever use someone else's toothbrush? You may think twice about doing it again after reading this: (1) Toothbrushes can be a source of repeated dental infections. (2) Toothbrushes can cause a bacteremia (bacteria entering the bloodstream) that may result in an endocarditis (a heart infection). (3) Toothbrushes can harbor and transmit viruses and bacteria. (4) Toothbrushes can retain 50% of the herpes simplex virus for one week. (5) Gingival [gum] inflammation can be reduced by changing toothbrushes biweekly.

Still think it's sexy to share a toothbrush? How about sharing food? Kissing? Certain bacteria can be transmitted from site-to-site in the mouth via dental instruments or from person-to-person sharing someone else's eating utensil. In juvenile periodontitis, virulent bacteria can move from an infected site to an uninfected site in the same mouth. Certain bacteria can be transmitted between spouses. Certain bacteria can be transmitted between parents and children. Certain bacteria can be transmitted from dogs to children.

So you see, bacteria once thought to be localized to specific sites in the mouth, can be migratory. We're not advocating that you stop tasting a scrumptious morsel or two at a four-star restaurant; we are advocating that everyone maintain good dental health not only for themselves but for the sake of those they love.

As far as ridding toothbrushes of bacteria, soaking them in a mouthrinse containing essential oils for 20 minutes kills 100% of the bacteria on the bristles. Ultraviolet light also sanitizes toothbrushes. But when researchers* tested the efficacy of using a toothpaste containing a common disinfectant compound - triclosan - they found little benefit when it came to eliminating the offending bacteria attached to the toothbrush bristles.

So what can you do about bacterial contamination from toothbrushes? Soak them in a suitable mouthwash, expose them to ultraviolet light, or from a practical stance, change them frequently. As for kissing someone, the benefits may still outweigh the risks :as long as you have an inkling as to their periodontal status!

*Warren DP, Goldshmidt MC, Thompson MB, Adler-Storhz K, and Keene HJ: The effects of toothpastes on residual microbial contamination of toothbrushes. JADA 132:1241-1245, 2001.