A study was made on 100 subjects of both sexes between the ages of 3 and 15 years to detect the presence of bacteria in the circulation after performing dental extractions. Two groups were formed of 42 and 57 subjects respectively. One of these groups was subjected to preoperative antisepsis of the region to be operated on, the rest of the conditions were similar for both groups. All the patients were submitted to a preoperative gingival smear and 5 c.c. of blood taken for cultures. Two postoperative blood cultures, one immediately after the operations and another 24 hrs. later were also done in all patients. All the extracted teeth presented severe infections at the root level and some showed complicated infection such as osteomyelitis. All blood cultures performed 24, 48, 72 hrs. and 21 days after the operation, were negative; therefore, there is no justification based on the study, to assume the existance of focal infection related to the presence of bacteremia.