Section II. PLAQUE, CALCULUS, AND STAINS
Basic information related to preventive dentistry is described in the paragraphs
that follow. This includes tests given during oral examination, types of dental plaques,
the formation of calculus, and the classification of dental stains caused by either
external or internal factors.
TESTS GIVEN DURING ORAL EXAMINATION
The dental specialist generally performs and records the tests that measure
gingival bleeding and plaque accumulation.
a. Gingival Bleeding Index . A gingival bleeding index (GBI) is a test to
determine if the gingiva bleeds upon slight provocation. The technique of performing
this test is very simple. Dental floss is inserted between the contact points of two teeth.
The floss is wrapped around the proximal surface in a bucco-lingual manner. The floss
is gently moved to the depth of the gingival sulcus. Then the floss is removed gently.
Test the mesial and distal surfaces of teeth numbers 3, 8, 14, 19, 24, and 30. Use
adjacent teeth if the patient is missing any of these teeth. The tested area should be
observed for 15 seconds. If bleeding occurs, mark a one (1) above the area on the
chart. If no bleeding occurs, mark a "0" for that area. The total of all the areas is the
gingival bleeding index. Procedures for taking the GBI is found in Appendix C.
b. Plaque Index. The plaque index measures stained plaque accumulation on
selected tooth surfaces. This parameter is a direct measure of the patient's oral
hygiene effectiveness. A step-by-step explanation of the plaque index is found in
a. General. It is generally agreed that the cause of dental caries and
periodontal disease is a substance called plaque. Mucin (a sticky protein material) from
the saliva adheres to the surfaces of the teeth when the teeth are not properly cleaned.
Food particles, dead tissue cells, and tissue fluids become trapped in the mucin,
establishing an excellent medium for the growth of bacteria and other microorganisms.
Once incorporated into mucin, these microorganisms are protected and are not
removed by the flushing action of saliva or any fluids taken by mouth. This mucin
network, with food, cellular debris, and exudate, becomes an excellent medium for the
growth of microorganisms. Once the microorganisms organize in this medium, they
protect themselves from the flushing and diluting action of the saliva. If the
microorganisms in these plaques are disorganized or broken up or if the plaque is
completely removed, then the cause of the disease is removed. Once the plaque is
removed, it takes about 24 hours for the microorganisms to reform, reorganize, and
resume production of damaging products.