Need to maintain as well as your teeth.
This thing is not 100 percent water tight.  The seal for the battery compartment is not that great.I have put Petroleum jelly on the seal and it works a little bit better.  Had it for 4 months and I had to tap the bottom of it like loading a magazine into a pistol to get it to start.  Come to find out that crud builds up underneath the brush shaft, hanging it up.  So I cleaned it and it works better.  Ive been stripping it down completely after each use to make sure moisture doesnt build up anywhere.
Rating: 3 stars