By Dr. Stephanie McGann, DMD FAGD, Columnist, The Times The toothbrush we know today has come a long way since it’s humble beginnings. The earliest toothbrushes were used by the Babylonians and Egyptians around 3500 BC. It was more of a tooth cleaning stick than a brush as we know it.  Small branches of the olive, sassafras or Salvadora persica trees were cut off and ends chewed until the wood fibers...