Toothbrush Abrasion

This patient was obsessed with brushing his teeth. He used a hard toothbrush and toothpaste and sat in front of the TV brushing back and fourth for fifteen minutes at a time. The hole you see in the depth of the notch is actually the nerve canal. The gums are swollen around the tooth as a result of the abscess, and we were unable to retract them further to show the full extent of the notch. the shape of the notch is typical of toothbrush abrasion. There is generally a sharp drop in the tooth structure where the hard enamel stops, and the softer root begins. The drop-off gradually subsides as the root approaches the gums. The gums are always under attack from the toothbrush, but they can rebuild themselves thus protecting the root underlying them from damage. They eventually loose the battle, but their gradual decline accounts for the gradual drop-off in tooth structure as the notch descends toward the gum line.

While this is the reason that dentists and hygienists always recommend that a patient use a soft toothbrush, years of research have shown that overly vigorous application of toothpaste(All brands, including the most popular ones such as Crest and Colgate) may be a more important factor than the hardness of the brush in producing these lesions. 

In order to avoid this type of tooth damage, it is recommended that patients learn to use the the more gentle technique discussed on my page on prevention, and to use mouthwash on their toothbrush instead of toothpaste. 

The image above is from a patient who presented to my office with a toothache in the lower left second premolar, the leftmost tooth in this image.  He was a serious brusher and used a hard toothbrush causing severe toothbrush abrasion in both premolars.  These lesions had been filled with composite about five years before this picture was taken, but since there was no tooth behind the second premolar, the patient had succeeded in actually brushing away the composite filling the defect.  He continued brushing away until he had exposed the nerve in the center of the tooth.  The hole you see close to the gums is the space where the nerve used to live.  Some research has shown that this type of damage does not happen if there is no toothpaste on the toothbrush.

The "Coke bottle" tooth image above, as well as the  one below shows extensive erosion of the cervical (around the gum line) tooth structure often attributed to abfraction.  This may, in fact, be the case, however evidence suggests that it is more likely to be due to overzealous tooth brushing with toothpaste.

The images below show extensive damage to enamel.  Many dentists believe that this is likely to be due to abfraction, however, toothpaste abuse alone may be the culprit.  In defense of the toothpaste abrasion theory, note the extreme smoothness and polishing of the lesions.

From the website of Dr Brian Palmer

Martin S. Spiller, D.M.D.

The images above, and the one below are somewhat different than the ones that preceded them. They are examples of what we call abfraction. this type of wear results from constantly grinding the teeth. This constant movement causes the teeth to bend very slightly at the point where the tooth root becomes immersed in the bone. this microscopic bending causes the enamel on the "upper" parts of the tooth to undergo micro-cracking and crazing. The loosened enamel is thus more susceptible to being brushed away. Note the difference in the pattern of wear. Abfraction affects enamel more than does toothbrush abrasion, which has more of an effect on the dentin of the root.

From the website of Dr Brian Palmer

Note also in the image above how shiny the teeth are.  The patient has literally scrubbed off all the surface anatomy from his teeth with his toothbrush and toothpaste.