Abstract
The purpose of this study was to investigate the relationship between the severity of the periodontal disease and the defective neutrophil chemotaxis in the patients with Down's syndrome (D.S. patients) .
Fourteen D. S. patients (9 males, 5 females, 12 to 34 years in age) were examined using the Plaque Control Record (O'Leary), Gingival Index (Löe & Silness), probing pocket depth and dental radiographs. The neutrophil chemotaxis in the D.S. patients and 14 healthy volunteers was measured with the agarose plate method modified by our laboratory and Boyden chamber method.
The results showed that the chemotactic index by the agarose plate method and the number of migration cells by the Boyden chamber method were significantly correlated (r=0.627, p<0.01) and the neutrophil chemotaxis in the D.S. patients was significantly impaired when compared with the healthy volunteers (p<0.01) . The neutrophil chemotaxis in 50 per cent of the D.S. patients was lower than the normal range of the healthy volunteers. No difference could be demonstrated between the D.S. patients and the healthy volunteers in the random migration of neutrophil.
From the radiographic analysis, three groups were divided according to the bone loss, which consisted of less than 4 parts, 4 to 6 parts and more than 6 parts of the upper and lower jaws (10 parts) . The patients with a high bone loss showed significantly a lower chemotactic index of neutrophil, whereas the D.S. patients with a slight bone loss showed almost a normal chemotactic index.
These results suggested that the defective neutrophil chemotaxis was one of the pathogenetic factors of destructive periodontal disease.
