periodontopathic bacteria in young healthy subjects of different ethnic backgrounds in los angeles. | 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. | 2002 | 11922257 |