Your toothbrush is your strongest ally in the fight against tooth decay and dental issues (second only to your dental hygienist, of course). However, under the right (wrong) circumstances, it is one of your greatest enemies.
According to researchers at the University of Manchester in England, one uncovered toothbrush can, and often does, house millions and millions of bacteria — this includes the infamous E. coli and staphylococci (“staph”) bacteria. Granted, our mouths regularly house a few hundred bacteria on a day-to-day basis; things become problematic when there is an overload of microorganisms. This is where the unclean toothbrush becomes a threat.
At Dental Health and Wellness Boston, Dr. Jill Smith makes it a priority to provide her patients with the best dental advice and care possible. With that in mind, here are some toothbrush tips for avoiding problems in the future, from Web MD:

Be aware of the proximity of your toothbrush to the toilet. This is essentially just common sense: every time the toilet is flushed, a spray of bacteria enters the air. That is not something you want landing on the bristles of your brush. So store your brush as far away from the toilet as you reasonably can.
Wash your brush. A simple tap water rinse every time you finish brushing is all you need.
Don’t share your brush! With anyone. Again, this seems like the most basic of common sense statements, but it’s still important to know. This includes housing the brush in the same cup as another brush; when the brushes touch, they can exchange germs. Give your brushes some breathing room (not breeding room).
Toss your toothbrush every three to four months. After a while, you need to replace the brush as the bristles fray and bend. If you have been sick or have a weak immune system, replace even more regularly. As far as power toothbrushes go, discard the head just as frequently.

Once you’ve mastered these toothbrush do’s and don’ts, we suggest some advanced tactics:

Use a power toothbrush. We at DHWB recommend and sell the Rotadent brand. Power brushes excel at cleaning areas that are hard to reach otherwise and are clinically proven to remove more plaque than the standard, “manual” toothbrushes.

Try Tooth and Gums Paste. It is fluoride-free and full of natural ingredients proven to aid in tooth maintenance, like extracts of Echinacea, red thyme, cinnamon bark and green tea.