Prevalence of Periodontopathic Bacteria in the Subgingival Plaque of a South Indian Population with Periodontitis 747-752
Assistant Professor, Department of Microbiology,
Dr. ALM PGIBMS, University of Madras,
Sekkizhar campus, Taramani.
Chennai, India - 600 113.
Phone: + 919840742105; Fax No: 91-44-24540709
Background: Periodontitis is an important global public health problem which involves mostly the adult population over 35-40 years of age. Strongly considering that periodontitis is a polymicrobial infection, the screening of the selective microbial population, rather than the isolation of a single member of the subgingival flora, should give a more wide-ranging perception in the aetiology of periodontitis. Different compositions of the bacterial species in the subgingival microflora of the periodontitis patients have been reported in diverse ethnicity. Similar studies on the bacterial aetiology of periodontitis is completely lacking in the Indian population.
Objectives: To detect and compare the prevalence of the eight putative, periodontal bacterial pathogens (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Eikenella corrodens, Prevotella intermedia and Prevotella nigrescens) among periodontitis patients and healthy subjects.
Materials and Methods: A total of four hundred subgingival plaque samples which were collected from two hundred periodontitis patients (chronic periodontitis patients-ChP, n=128, aggressive periodontitis patients-AgP, n=72) and two hundred healthy subjects was subjected to Polymerase Chain Reaction (PCR) with the help of species specific primers which targeted the 16S rRNA gene of the bacterial species. The statistical analysis was performed by using the Chi-square test.
Results: The prevalence of various microorganisms in chronic periodontitis (n=128), aggressive periodontitis (n=72) and in healthy subjects (n=200) was 80.5%, 73.6% and 11% for P. gingivalis, 73.4%, 59.7% and 10.5% for T.forsythia, 71.1%, 33.3% and 5.5% for T. denticola, 32.0%, 61.1% and 2.5% for A. actinomycetemcomitans, 17.2%, 11.1% and 8.5% for C. rectus, 15.6%, 11.1% and 6% for E.corrodens, 16.4%, 25.0 % and 7.5% for P. intermedia and 13.3%, 13.9 and 14% for P. nigrescens respectively.
Conclusion: The present study demonstrated a high prevalence of the red complex group (P. gingivalis, T. forsythia and T. denticola) in the ChP patients. The high odds ratio for P. gingivalis, T.forsythia, T.denticola and A.actinomycetemcomitans suggested a strong association between them and periodontitis. The incidence of A.actinomycetemcomitans along with P.gingivalis and T.forsythia was high in AgP. An appropriate therapeutic strategy can be considered in view of these bacterial consortiums. In addition, two formerly unreported symbiotic relationships were found between the 8 bacterial species which were analyzed.