Use of ultrasound Doppler to determine tooth vitality in a discolored tooth after traumatic injury: its prospects and limitations
A 47-year-old female patient visited our department due to traumatic injury to her upper right lateral incisor (tooth #12). She sustained the injury 3 days before she visited our clinic by a fist blow injury to her face. Tooth #12 was subluxated, and showed a positive response to a percussion test. It did not show any response to a cold test or EPT. The tooth was diagnosed with subluxation, and we decided to wait and observe its course. There was no discomfort during the 2 weeks after the injury, but there was no response to the thermal test or EPT, and a reddish discoloration was observed ().\nAt 6 weeks after the injury, the patient did not show any discomfort, but the discoloration lasted, and the tooth did not respond to cold or EPT. We decided to use the ultrasound Doppler unit to evaluate the vitality of the pulp, and the result was shown in . Tooth #12 produced a typical pulsated image, which represents normal vital pulp (). We explained the results and implications of the test to the patient. We decided to continue to wait and observe the tooth because the patient had no discomfort, did not mind the discoloration at that time, and was willing to wait to determine whether the tooth could recover to normal without any treatment. At 10 weeks after the injury, the tooth had returned to a normal shade and regained its normal responses to the cold test and EPT ().