OBJECTIVE The dental pulp is a low-compliance system that is particularly vulnerable to physiologic changes. Prolonged vasoconstriction may have detrimental effects. This goal of this study was to determine whether 2% lidocaine with 1:100,000 epinephrine, as used for buccal infiltration, decreases the blood flow in the dental pulp and adjacent gingival tissue. METHODS The Periflux PF3 laser Doppler monitored pulpal and gingival blood flow before and after injection with local anesthetic. Ten human volunteers with at least one healthy and unrestored maxillary premolar were used in this study. RESULTS After injection of 0.9 ml of 2% lidocaine with epinephrine, there was a significant reduction from baseline values (p > 0.05) in both pulpal (73%) and gingival (51%) blood flow rate in all volunteers. Blood flow had not returned to baseline values after 1 hour. CONCLUSIONS This study showed that 2% lidocaine with 1:100,000 epinephrine significantly reduced blood flow pulpally and gingivally. Pulpal blood flow reduction was more than gingival blood flow reduction, which may be critical for compromised pulps with already reduced blood flow. The gingival effects may be of relevance with soft tissue procedures.