RESUMO
BACKGROUND AND OBJECTIVE: Insufficient information on the cellular composition of long-standing gingivitis lesions without signs of attachment loss makes an understanding of differences in cellular composition between "destructive" and "nondestructive" periodontal lesions difficult. The aim of the current study was to analyze differences in cell characteristics between lesions representing long-standing gingivitis and severe periodontitis. MATERIAL AND METHODS: Two groups of patients were recruited. One group consisted of 36 patients, 33-67 years of age, with severe generalized periodontitis (periodontitis group). The second group consisted of 28 patients, 41-70 years of age, with overt signs of gingival inflammation but no attachment loss (gingivitis group). From each patient a gingival biopsy was obtained from one selected diseased site and prepared for immunohistochemical analysis. RESULTS: Periodontitis lesions were twice as large and contained significantly larger proportions, numbers and densities of cells positive for CD138 (plasma cells) and CD68 (macrophages) than did gingivitis lesions. The proportion of B cells that expressed the additional CD5 marker (B-1a cells) was significantly larger in periodontitis lesions than in gingivitis lesions. The densities of T cells and B cells did not differ between periodontitis lesions and gingivitis lesions. T cells were not the dominating cell type in gingivitis lesions, as B cells together with their subset plasma cells comprised a larger number and proportion than T cells. CONCLUSION: Periodontitis lesions at teeth with advanced attachment and bone loss exhibit quantitative and qualitative differences in relation to gingivitis lesions at teeth with no attachment and bone loss. It is suggested that the large number and high density of plasma cells are the hallmarks of advanced periodontitis lesions and the most conspicuous difference in relation to long-standing gingivitis lesions.