Section VI. PERIODONTAL DISEASES
Periodontal diseases involve the periodontal tissues. When considering the
causes of these diseases, both systemic and local factors must be taken into account.
Periodontal diseases involve the supporting structure that maintains a tooth within the
dental arch. This includes the periodontal ligament, the alveolar bone, and the gingiva.
An inflammatory process or trauma generally initiates periodontal disease; however,
systemic considerations can also influence the susceptibility and degree of involvement.
Gingivitis (figures 1-4 and 1-5) is an inflammation of the gingival tissues. It is
characterized by the typical signs and symptoms of inflammation--swelling (edema),
redness, pain, increased heat, and, sometimes, disturbance of function. Most patients
that appear to have clinically healthy gingiva also have minute areas of inflammatory
activity. The inflammation is caused by the toxic substances produced by bacteria in
the mucinous plaques adjacent to the gingival tissue. Direct irritation from food
impaction, toothbrush bristles, or toothpicks may also cause gingival inflammation. With
inflammation, the gingival tissue appears to proliferate. The inflammatory gingival
response causes a swelling of the tissue caused by increased vascular activity. This
increases the depth of the gingival sulcus (a furrow between the surface of the tooth
and the gingiva) around the involved teeth, increasing the potential for continued and
further gingival involvement. The increased depth of the sulcus allows additional debris
to accumulate and more plaque to form. If this plaque is not removed, it may become
calcified from the precipitation of calcium salts from the saliva. The calcified plaque is
Inflammation of the gingival tissues is evident at the neck of these maxillary
and mandibular anterior teeth. Note the redness and bulbous engorgement
(edema) of the tissue as well as the lack of normal tissue texture. Dental
plaque accumulation accounts for this inflammatory response.
Figure 1-4. Gingivitis, tissue inflammation.