Frequency of accidental intravascular injection of local anesthetics in children.

Blood was aspirated in 1.7 percent of the cases, 3.1 percent of inferior alveolar block cases, and 2.2 percent of the cases where infiltration was used for the maxillary molars. It was in children eight to ten years of age that 67.2 percent of the positive aspirations occurred, although that age-group composed only 44.5 percent of the sample.