RESUMEN
The objective of this randomized double-blind investigation was to compare the anesthetic efficacy and injection discomfort of 3 volumes of 2% lidocaine with 1:100,000 epinephrine for maxillary infiltration anesthesia. A total of 25 subjects received 0.6, 0.9, and 1.2 mL of the anesthetic buccal to an upper canine. Test teeth were assessed with electrical stimulation to determine onset and duration of pulpal anesthesia; soft tissue anesthesia and injection discomfort were assessed by pin-prick test and visual analog scale (VAS). Data were analyzed by 2-way analysis of variance (ANOVA), Friedman, and chi-square tests (alpha = 5%). The 1.2 mL dose induced faster onset of pulpal anesthesia, a higher success rate, and a longer duration of soft tissue/pulpal anesthesia than were achieved with the other doses (P < .05). No differences in injection discomfort were observed between treatments. It is concluded that maxillary infiltration anesthesia with lidocaine and epinephrine has a faster onset, a greater success rate, and a longer duration when a volume of 1.2 mL is used than when volumes less than 1.0 mL are used.