We would advise that brushing your teeth only once a day is not enough and that regular twice daily brushing is considered best. This is the most helpful way of ensuring healthy teeth and gums as well as maintaining a nice taste to the mouth and fresh smelling breath. But is it actually possible to brush your teeth too much?
Scientifically there is circumstantial evidence through case reports, epidemiological data and studies that tooth brushing with toothpaste is implicated with tooth wear, gingival or gum recession and dentine hypersensitivity (Addy M and Hunter M: Can Tooth brushing damage your health? International Dental Journal, 2003; 53: 177-186). In other words tooth brushing with toothpaste can recede your gums, wear down your teeth and make them sensitive to cold. But is that under normal use or when you brush too much or brush incorrectly?
Misconceptions about teeth brushing
There are too many misconceptions even amongst dentists let alone the general public regarding brushing your tooth enamel away by brushing too much or scrubbing at your teeth. Before considering this in more detail it is important to note that a healthy normal crown of a tooth is made of a strong outer shell of enamel. This covers an inner core of dentine which is thicker but softer, housing the nerve and blood supply of the tooth. Under normal use, tooth brushing alone will not wear away your enamel and even extended periods of use over years would only cause minute wear of the softer dentine. Even when combined with toothpaste but in the absence of acids there is no wear of the enamel as both the toothbrush bristles and toothpaste are not as hard as the enamel itself. However, when dentine is exposed tooth brushing with toothpaste abrades the dentine which is relatively soft. The toothpastes contain abrasive substances which are used to remove stains and other superficial deposits from the tooth surface. To put this into context “under normal use the loss of 1mm of dentine would occur in 80 to 100 years of brushing”(Addy M and Hunter M: Can Tooth brushing damage your health? International Dental Journal, 2003; 53: 177-186). Abusive or abnormal brushing with toothpastes still has relatively little effect on the wear of enamel surfaces but exposed dentine begins to wear dramatically to pathological proportions.
So what does excessive or incorrect brushing do?
As explained earlier you cannot wear away the enamel no matter how much or how badly you brush as long as the environment of the mouth is not acidic. Hence damaging the enamel of your teeth when brushing only occurs if you brush straight after you have had acidic foods or drinks or you brush when the mouth has become acidic as a result of acid reflux from the stomach.
Recession of the gums is a multi-factorial condition but is commonly associated with improper or excessive brushing especially on teeth that are prominent in the mouth. The process means that the gums recede up thereby exposing the roots of the teeth that are not covered by enamel but are merely made of the softer dentine which is liable to be abraded away with excessive or improper tooth brushing. The process is made far worse if the conditions are acidic and substantial damage is done to the neck of the teeth.
The damage caused to the exposed dentine as a result of excessive or improper brushing following gum recession sometimes leads to dentine hypersensitivity making the teeth sensitive to cold foods and drinks.
In conclusion can you brush your teeth too much?
The answer is that under normal circumstances using the correct type of brush and brushing technique in the absence of acids we cannot brush too much but usually brushing twice a day and cleaning between the teeth using floss or other inter dental aide is enough to ensure healthy teeth and gums.