My mom always told me to brush my teeth in cold water, so the bristles lasted longer. My boyfriend’s family always used to brush their teeth while showering - in warm water.
Who is right? Will a toothbrush deteriorate faster in warm water, or does water temperature make no difference to the toothbrush? I searched, but it doesn’t appear that Cecil has scientifically tested this one yet.
I find that warm or hot water makes the bristles more pliable. I suppose that could make them go out of line faster. The bristles are still going to get warm in your mouth anyway though if you use cold water.
A better question is why would someone be concerned with maximizing the life expectancy of toothbrushes. They only cost a few dollars and last for months.
Yea, the bristles will soften when you heat them with warm water.
I consider this to be a neat “feature” of the bristles: if you want harder bristles, pre-rinse them with cold water. If you want softer bristles, pre-rinse them with warm or hot water.
Not sure how this affects longevity. But it would be reasonable to assume that using warm or hot water to soften the bristles will decrease their life.
According to what my dentist says, you should replace a toothbrush at least every 6 months anyway.
I’ve allways been a cold water brusher, but my girlfriend uses piping hot water because she insists that her teeth get cleaner that way–the same reasoning for using hot water to wash dishes I guess. For me–I just dont get that minty fresh feeling when the water’s hot. I do wonder though if toothpastes are designed to be most effective at certain temperatures, or if it would matter either way.
Life expectancy of toothbrush = One Month!! :wally
I recently read a summary of a study–no links, sorry–that raised questions about the sanitation of hot water in homes, especially in seldom-used faucets. According to theory, the water doesn’t get hot enough to sterilize the water, but does get hot enough to provide an almost ideal medium for bacterial growth that line the water pipes.
Re: longevity of toothbrush, yes, using cold water may extend their lifespan but, as said above, dentists caution against keeping toothbrushes too long, as they become coated with a host of microscopic nasties.
I use a Sonicare electric toothbrush. The heads cost around $35.00. Life expectantcy is important.
Given that my wet toothbrush has been sitting out in a dusty bathroom collecting who-knows-what kind of microbes (c.f. “fecal plume”), I tend to start off a brushing episode by washing it in as hot a stream of water as my faucet can deliver. This has never seemed to have much of an effect on the toothbrush’s life.
I suspect the abrasive properties of your toothpaste and the general scrubbing action of its intended use have a greater effect on toothbrush life.
Well, perhaps when you both get old enough, you can just pop your teeth in the dishwasher. 
:eek: What model my Sonicare (Pro?) heads are 2 for $20.