Bacterial Analysis of Subgingival Plaque in Adolescent

Objective: To analyse the correlation between the periodontal.clinical parameters and putative periodontal pathogens in adolescent.Methods:Subgingival samples (n=108/11-17year) were divided into 3 groups: Control group (H): n=30, Gingivitis group (G): n=60, Periodontitis group (P): n=16. The clinical parameter: Gingival index (GI), Probing depth (PD),Sulcus bleeding index (SBI) and Clinical attachment level (CAL) were assessed. Bacteria cultivated black- pigmented bacteroides, Actinomyces spp, Actinobacillus actinomycetemcomitans (A.a), and Fasobacterium nucleatum(Fn), identificated (flora characterization, Gram's stained, and biochemical examinations), calculated the colony-forming unit per ml (CFU/ml) and statistically analyzed (SPSS). Results:1. In H, G and P, the detectable rates of black-pigmented bacteroides, Actinomyces spp., F.n and A.a were 3.33%, 100%, 90%, 83. 33%, 88.89%, 93.33%, 88.89%, 30%, 68.33%, 20%, 33.33%, 72.22%, respectively. Among above, black- pigmented bacteroides, F.n and A.a were significantly different (p<0.01). The detectable rates of black-pigmented bacteroides, F.n were significantly high in G than H , and black-pigmented bacteroides, A.a were significantly high, in P than G..2. In H, G and P, the numbers of black-pigmented bacteroides, F.n, Actinomyces spp., and A.a were statistically significantly different(p<0.01). The number of black pigmented bacteroides, Actinomyces spp. and F.n was significantly more in G than H, and black pigmented bacteroides, Actinomyces spp, F.n was significantly more in P than G.3. There is a statistically significant correlation between SBI and the detectable rates of black-pigmented bacteroides, F.n,and A.a, and between SBI and the number of anaerobe, black-pigmented bacteroides, F.n, A.a and Actinomyces spp. 4. There is a statistically significant correlation between PD and the detectable rates of black-pigmented bacteroides, F.n, and A.a , and between PD and the numbers of F.n and A.a.Conclusions: The results suggest that black-pigmented bacteroides, A.a, and F.n with periodontal inflammation of tissue broken, bleeding and pocket deeping have a certain relation.