RESUMO
BACKGROUND: This study aimed to assess factors associated with occurrence of pulp necrosis (PN) in traumatized primary incisors, which may contribute to the prognosis of this outcome. DESIGN: Data were collected by single examiner through the analysis of clinical files of traumatized patients. The occurrence of PN in traumatized teeth was the evaluated outcome. Poisson regression analysis was applied to calculate the relative risk (RR) and the respective 95% confidence interval. RESULTS: Five hundred and twenty-one files were assessed, summing up 727 traumatized primary incisors. The proportion of teeth affected by PN was 23.8%. Multiple regression analysis indicated the following factors as positively associated with PN: trauma with displacement, pulp exposure fracture, self-report of pain, yellow, grey and brown crown discoloration, internal root resorption, and bone loss. Trauma in 4- to 5-year old and more than 5-year-old children, pulp canal obliteration, and external root resorption with bone formation were negatively associated with PN. CONCLUSIONS: Teeth that suffered more aggressive injuries, pain, some types of discoloration, and other radiographic findings (for instance, internal root resorption) are positively associated with the occurrence of PN. On the other hand, trauma in older children, canal obliteration, or external resorption show less probability of PN.
