Pulpal blood flow assessed by laser Doppler flowmetry in a tooth with a horizontal root fracture

Horizontal root fractures of both maxillary central incisors were diagnosed radiographically; neither responded to electric pulp testing nor to cold testing. The pulp of the right incisor was necrotic, whereas the pulpal status of the left incisor was uncertain. Pulpal blood flow of the teeth was measured with laser Doppler flowmetry. The blood flow of the left central incisor was 4.0. Eight months after the injury, a local anesthetic with a vasoconstrictor was administered to confirm pulp vitality. The blood flow of the tooth was decreased to 51% of the preanesthesia value after the local anesthesia. At 19 months after the injury, it responded to both the electric pulp test and cold test. Laser Doppler flowmetry is a noninvasive method of evaluating the blood flow status in human teeth, and it may provide a clinically reliable method of assessing pulpal vitality.