horizontal resorption producing an irregular alveolar crest. When patients have good
plaque control the degree of bone resorption is not commensurate with the level of
oral hygiene. The more generalized nature of the disease predisposes to multiple and
recurrent abscess formation which is a common presenting feature.
Invariably, one of the presenting signs is tooth migration or drifting of incisors. Tooth
movement is not necessarily a consequence of advanced disease as drifting may occur
when only a fraction of a tooth's periodontal support is lost. Conversely, extensive
bone loss can occur with no spontaneous movement of teeth and the subject may only
be alerted to the problem when a minor traumatic episode, such as a blow to the
mouth during a sporting activity, causes unexpected loosening of teeth.
Bacteriology and pathogenesis
The subgingival microflora comprises loosely adherent, Gram-negative anaerobes
including Eikenella corrodens, Capnocytophaga spp., and Prevotella intermedia. The
most frequently implicated organism is Actinobacillus actinomycetemcomitans, which
has been found in over 90% of patients. Sufferers also have raised IgG titres to A.
actinomycetemcomitans, but levels of the bacteria fall significantly following
successful treatment of the condition.
Key Points
Permanent dentition (Juvenile periodontitis):
- onset around puberty;
- localized/generalized;
- Actinobacillus actinomycetemcomitans;
- neutrophil chemotaxis defect.
The extreme pathogenicity of A. actinomycetemcomitans is due to its ability to invade
connective tissues and the wide range of virulence factors that it produces. These
include a potent lipopolysaccharide that induces bone resorption, collagenase, an
epitheliotoxin, a fibroblast-inhibiting factor, and a leucotoxin that kills neutrophils
and so dampens the host's first line of defence against bacterial challenge.
About 70% of patients have defects in neutrophil chemotaxis and phagocytosis. The
chemotactic defect is linked to reduced amounts of cell-surface glycoproteins and is
transmitted as a dominant trait. About 50% of siblings of patients who have both
aggressive periodontitis and chemotactic defects, also demonstrate impaired
neutrophil function.
Treatment
A combined regimen of regular scaling and root planing with a 2-week course of
systemic tetracycline therapy (250 mg, four times daily) has been used extensively in
the management of this condition. A. actinomycetemcomitans is sensitive to
tetracycline, which also has the ability to be concentrated up to 10 times in gingival
crevicular fluid when compared with serum. More recently, a combination of
metronidazole (250 mg) and amoxicillin (amoxycillin) (375 mg), three times a day for
1 week, in association with subgingival scaling, has also been found to be effective.