Several investigations have demonstrated toothbrush-induced bacteremias. Transient bacteremias are well tolerated by healthy individuals but may increase endocarditis risk in patients with cardiac conditions. This study assessed bacteremia levels after brushing with either the Sonicare electric toothbrush or a manual toothbrush.Fifty healthy children receiving dental treatment under general anesthesia with oral intubation were randomly assigned to a manual or Sonicare group. Plaque levels and gingival health were scored and a blood sample collected. Teeth were brushed for 1 minute and a postbrushing blood sample was drawn. Samples were analyzed for aerobic and anaerobic bacterial growth.Gingival health and plaque scores did not differ between groups. No correlation was detected between plaque and gingival scores and occurrence of bacteremia. The frequency of bacteremia was 46% with manual brushing: 18% aerobic, 9% anaerobic and 73% both. This differed significantly (P = .022) with 78% bacteremias in the Sonicare group: 22% aerobic, 22% anaerobic and 56% both.The Sonicare induced significantly more bacteremias than manual toothbrushing. These results show that vigorous brushing increased bacteremia from one brushing but does not answer whether bacteremia incidence would decrease with a program of vigorous daily brushing; this should be clarified before recommending brushing methods for patients with compromised cardiac conditions.