i buy a new toothbrush about every four months, brush once in the morning with a gargle of peroxide, then brush again after my evenin shower.

from research i've found that teeth need to be brushed "with the grain" to best preserve them. the top incisors need to be brushed by starting at the top, pulling it down the tooth, pulling the brush away from the tooth and repeating that. that is NOT to go up tooth or sideways. it actually wears your teeth down. bottom teeth are the opposite.
it's real easy to do fast, though it *sounds* tedious. it's a cinch.