Toothbrush bristles are rounded at the factory, but once the bristles wears away with use, your toothbrush becomes like a knife with jagged edges.
It is possible to over brush. I would estimate that 80% of us are over brushing. We’re obsessed, but we’re brushing incorrectly and we’re brushing with the wrong toothbrush. I see everyday people in my practice that have brushed away tooth structure and worn their teeth away using a toothbrush. There is absolutely such a thing as too much of a good thing when it comes to brushing your teeth.
Think about, for a moment, what a toothbrush is and how it is made. A toothbrush is manufactured by taking a grouping of nylon bristles and inserting them into a molten nylon handle. A machine cuts these bristles to make them all the same height. At this point in the manufacturing process, if you were to look under a microscope with extreme magnification, you would see thousands of little cylindrical nylon tubes with sharp and serrated edges, waiting to scrape away precious dentin and enamel.
Fortunately, there’s another step in this manufacturing process that most (not all) quality toothbrushes undergo. After the bristles are cut to be the same height, they are treated in such a way that the sharp edges of the nylon bristles are rounded into hemispherical, soft domes – this, too, is visible underneath the microscope. This process makes the toothbrush bristles safe to use. After being rounded, they are far less abrasive than when they are freshly cut and safe to use because they don’t scrape away tooth structure.
Certain toothbrush manufacturers do a better job of this than others. The toothbrushes made by manufacturers that don’t do a great job rounding the bristles are not safe to use out of the box. This cannot be seen with the naked eye.
The smoothness of your bristles also gets worn away back to its original jaggedness via brushing, which is why you may have heard that dentists recommend you replace your toothbrush often. The key is to throw away your toothbrush before the bristles splay, because by that point, it’s too late. Splayed bristles mean you’ve been using a worn toothbrush that is too abrasive and has been wearing away your tooth structure. I recommend replacing your toothbrush every four weeks for people who brush twice a day. The analogy I like to use is this one: would you wax your car with an old rag with dirt on it? Never, because that would scratch the finish. The same goes for your teeth.
If you use proper techniques in brushing, use a high quality toothbrush, and you throw it away before it becomes this dangerous, abrasive device I’ve described, you should be able to eat frequently and brush frequently without guilt. As an aside, you can never floss too much – you can only floss too little. Bummer, huh?
Mark Burhenne DDS