RESUMEN. Antecedentes : existe evidencia clinica y experimental que la proteina C reactiva (PCR) es un marcador de inflamacion sistemica asociado a periodontitis cronica, siendo esta enfermedad la principal causa de edentulismo. Objetivo : identificar microorganismos periodontopatogenos presentes en pacientes edentulos y en pacientes con periodontitis moderada/avanzada y establecer su relacion con la proteina C reactiva ultrasensible (PCR-us). Metodos : estudio de corte transversal en 61 pacientes mayores de 30 anos divididos en dos grupos: con periodontitis cronica y edentulos, A cada paciente se le tomo una muestra de saliva y del dorso de la lengua para identificacion microbiologica de microorganismos y muestra serica para evaluacion de PCR-us. La asociacion microorganismo, PCR-us, grupo paciente. Resultados : PCR-us mostro un valor maximo de 1,12 mg/l en el grupo de edentulos sin ninguna diferencia estadisticamente significativa con el grupo de periodontitis cronica (p=0,29); sin embargo, valores mayores de PCR-us se observaron en pacientes con microorganismos como Candida albicans , Porphiromona gingivalis , Actinomyces naeslundii (A. naeslundii), Capnocytophaga sp , Streptococcus intermedius (S. intermedius) , y Bacteroides thetaiotaomicron. Conclusion : De acuerdo con los resultados de este estudio, no hay diferencia en PCR-us entre pacientes edentulos y aquellos con enfermedad periodontal. Se encontraron periodontopatogenos en edentulos principalmente Capnocytophaga sp , A. naeslundii y S. intermedius , tanto en lengua como en saliva. ABSTRACT. Background : There is clinical and experimental evidence that the C-reactive protein (CRP) is a marker of systemic inflammation associated with chronic periodontitis, being this oral disease the main cause of edentulism, and sharing in some cases, some microorganisms. Purpose : To identify periodontal pathogens in edentulous and moderate/severe periodontitis subjects, and stablish its association with us-CRP. Methods : Cross sectional study in 61 patients older than 30 years old, divided in two groups: The edentulous group and the other with chronic periodontitis. A sample of saliva and tongue dorsum surface was collected for microbiological identification, and serum us-CRP levels were also evaluated. An association between the microorganisms and the us-CRP in each group of patients was investigated. Results : us-CRP showed a maximum level of 1.12 mg/l in the edentulous group with no statistically significant difference when was compared with the periodontitis group. However, the presence of microorganisms such as Candida albicans , Porphiromona gingivalis , Actinomyces naeslundii ( A. naeslundii ), Capnocytophaga sp , Streptococcus intermedius ( S. intermedius ), and Bacteroides thetaiotaomicron was associated to a slight increase in the serum us-CRP levels. Conclusion : According to the results of this study, there´s no difference in us-CPR between edentulous patients and those with periodontal disease. We found periodontopathogens in edentulous mainly Capnocytophaga sp , A. naeslundii , and S. intermedius in tongue and saliva.