Pulpal response to sensibility tests after traumatic dental injuries in permanent teeth

Background/AimThe assessment of pulp vitality is one of the major challenges in dental traumatology due to the temporary loss of sensibility after trauma and because of the limitations of conventional pulp tests. The aim of this study was to evaluate pulpal response to sensibility tests and to determine their accuracy after crown fractures and luxation injuries. Materials and methodsA total of 121 permanent anterior teeth from 78 patients treated at the Dental Trauma Clinic of the Federal University of Minas Gerais were evaluated. Responses to pulp sensibility tests were monitored for a minimum period of 24months or until the diagnosis of pulp necrosis. ResultsAt the first appointment, 68 teeth responded positively to sensibility tests, one tooth was necrotic and 52 teeth did not respond to sensibility tests but showed no other signs of necrosis. The initial lack of response was not associated with age (P=0.18), but was related to the presence of luxation (P<0.001). At the final appointment, 87 teeth were classified as vital and 31 were classified as non-vital. While a positive response shortly after trauma was a good predictor of vitality, a lack of response was not associated with subsequent necrosis. The final pulpal condition of the teeth that initially did not respond was associated with the type of injury, as displaced teeth tended to develop necrosis (P=0.008). The accuracy of each sensibility test at the initial and final appointments was, respectively, 55.1% and 67.8% for the heat test, 55.9% and 77.9% for the cold test, and 57.6% and 89% for the electrical test. Conclusions. A temporary loss of sensibility was a frequent finding during post-traumatic pulpal healing, especially after luxation injuries. All sensibility tests presented low accuracy shortly after trauma. The electrical test provided the best support for pulpal diagnosis after long-term follow up. The clinician must be aware of additional signs of crown discoloration and radiographic changes before initiating endodontic treatment.