Periodontopathic Bacteria in Young Healthy Subjects of Different Ethnic Backgrounds in Los Angeles

Background: The present study determined risk indicators for oral colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, and Treponema denticola in 150 children and adolescents, 4 to 16 years of age, living in Los Angeles, California. Methods: Fifty Caucasians, 50 Hispanics, and 50 Asian‐Americans completed a questionnaire on demographic characteristics. 16S rRNAbased polymerase chain reaction identification was employed to determine the presence of test bacteria in unstimulated saliva. Step‐wise logistic regression analysis identified explanatory variables (risk indicators) accounting for the salivary presence of periodontopathic bacteria. Results: A. actinomycetemcomitans occurred in 15%, P. gingivalis in 15%, B. forsythus in 14%, and T. denticola in 18% of all subjects. Two or more pathogens were detected in 20% of Hispanic subjects and in 12% of Asian‐American subjects but not in any Caucasians (P = 0.0005, chi square test). However, no stable multivariate model including ethnicity was found for multiple pathogens. Risk for harboring any pathogens increased with the length of time lapse from last dental visit (odds ratio [OR], 4.46; 95% confidence interval [CI], 1.83 to 12.21), and decreased with higher education level of the mother (OR, 0.258; 95% CI, 0.052 to 0.875). Risk for harboring 2 or more periodontal pathogens decreased with the years the parents had resided in the United States (OR, 0.95; 95% CI, 0.901 to 0.992). Risk for harboring A. actinomycetemcomitans decreased as the number of years the parents had resided in the United States increased (OR, 0.91; 95% CI, 0.86 to 0.95), and decreased with higher income level of the father (OR, 0.201; 95% CI, 0.038 to 0.948). Girls were at higher risk for harboring P. gingivalis (OR, 2.55; 95% CI, 1.02 to 7.03), but at lower risk for carrying T. denticola (OR, 0.42; 95% CI, 0.17 to 0.98). Conclusions: This study showed that salivary occurrence of periodontopathic bacteria in young individuals was related to the length of time the parents had lived in the United States, education level of the mother, length of time since last dental visit, and gender, but apparently not to ethnicity per se. J Periodontol 2002;73:283‐288.