(2) The danger area of the face. Some veins of the face, particularly in the
upper lip and the nose area, are directly joined to the cavernous sinus. See figure 2-16.
Excessive irritation or aggravation of infected tissues, whose venous drainage is
connected to the cavernous sinus, may result in a spread of infection to the cavernous
sinus and then to the brain. For this reason, particular caution should be used to avoid
needless aggravation of infected tissue in these areas. This venous drainage pattern is
of particular importance since the veins of the face contain no valves as do veins in
other parts of the body.
(3) Seriousness of infection. An infection in the facial area, to include the
maxillary anterior teeth, can travel upward and rearward into the cavernous sinus. This
may cause a cavernous sinus thrombosis or clotting of the blood in that area. Stopping
the blood flow in the cavernous sinus would then cut off the flow to other parts of the
brain. Lack of blood flow to the brain deprives it of oxygen and causes brain damage or
death. Therefore, any infection in the upper teeth or facial area needs to be treated by
the dental officer immediately.
Figure 2-16. Danger area of the face.