Coronal discoloration is a common sequela to traumatic injuries. In subluxation cases, although the injury is not strong enough to rupture the apical vessels, discoloration may appear by tearing thin walls or occluding small capillaries. In absence of infection pulpal regeneration can occur, and as a result discoloration may completely or partially subside. But judging pulpal status by coronal discoloration can be dangerous and it may lead to unnecessary treatment.
This case presents coronal discoloration and recovery following traumatic injury of maxillary anterior teeth. In diagnosing traumatized teeth routine cold tests or electric pulp tests are known to be unreliable, but with the aid of ultrasound doppler imaging, assessing pulp vitality of traumatized teeth can be more accurate.
Use of electric pulp testing elicits painful response in vital teeth. In this study, we examined the excessive time from pain feeling to stimulation disconnection in clinical situation. D626D (Parkell Inc., USA.) scan type electric pulp tester was used in total of 23 young healthy individuals. Each of the right central incisors and first premolars were used as testing teeth. Stimulation disconnection was achieved by EMG in anterior belly of digastric muscle, finger span, and voice and the excessive stimulation time over the sensory threshold was recorded. As a result, we found that the short responses before the stimulation disconnection appeared following order; EMG, finger span, and voice. The EMG disconnection is suggested to be used to reduce the excessive stimulus time in electric pulp testing.