Dental Education Lecture: How to Brush?

In last lecture, we discuss that we need to brush our teeth in three distinct areas.  In this lecture, we are going to show you where is the most dirty area in our teeth.  A special stain can be used to show plaque, germ products, in our tooth surface.  After we stain the teeth, we let patients rinse the mouth.  What is left is plaque.  The staining intensity is quite variable, from blue to pink.  The most intense staining (blue) is found at the junction of teeth and gums (arrow in Fig.1).  That is the most dirty area in our teeth.  This is the area we should concentrate upon.  Let us use Fig.2 to show again the junction between teeth and gums, pointed by an instrument.

Let us brush the buccal surface (next to our cheek) of teeth at 45 degrees aiming at the junction between teeth and gums as shown in Fig.3.  When we brush our back teeth, the motion should be back and forth.  Since our teeth are aligned in an arch form, we need to change brush angulation so that there is maximum contact brush and teeth.  The motion of brushing front teeth is side to side. Surprisingly, we do not brush our front teeth very well as shown in Fig.1.  Then brush the other side of back teeth.  The sequence of brushing the buccal surface of our teeth is shown by arrows in Fig.4.

Brushing toward the junction between teeth and gums at 45 degrees is the most efficient way to remove plaque.  Since there is also gum tissue on the tongue side of our teeth, we should brush in the same manner, at 45 degrees (Fig.5).  This is the second surface of teeth we need to brush.

However, side-to-side brushing for the inner (tongue) surface of the lower front teeth is not so effective.  Contact between toothbrush and teeth is not much (Fig.6).  We need to change of direction of brush (Fig.7).  As you may see, contact between brush and teeth is quite a lot.  Brush inside out at approximately 45 degrees.

The last surface to be brushed is the biting surface of back teeth at 90 degrees (Fig.8).  Diligent brushing in the right manner is one of ways to keep our teeth and gums healthy, but brushing itself is not enough.  Next lecture will show you that there is still plaque left after thorough brushing and how to achieve perfect oral hygiene.

Xin Wei, DDS, PhD, MS 1st edition 01/24/2009 , last revision 03/20/2010