Analysis of the crown fractures and factors affecting pulp survival due to dental trauma.

OBJECTIVES: The aim of the present study was to investigate pulp survival following crown fracture with and without pulp exposure as well as with and without associated subluxation and in relation to stage of root development and type of enamel-dentine fracture. MATERIALS AND METHODS: This study consisted of 83 patients with 116 crown fractured incisors without pulp exposure and 35 patients with 44 complicated crown fractures. The effect of variables on the maintenance of tooth vitality were explored using the Linear Regression analysis , which assumes the effects of different factors on the pulp vitality such as (age, stage of the root development, contaminant subluxation, fracture depth, emergency treatment). RESULTS: The general distribution was 59 (71%) boys and 24 (29%) girls with uncomplicated crown fractures aged 7-17 years, mean 10.7 years ±2.83SD and 24 (68.5%) boys and 11 (31%) girls with complicated crown fracture. From 78 uncomplicated crown fractures without subluxation PN (pulp necrosis) was evaluated in 4 (4.88%) cases but from 20 uncomplicated crown fractures with subluxation PN was 14 (56.52%) cases. Univariate analysis showed that stage of root development p<0.05, subluxation p<0.001, fracture depth p<0.001 were significantly related to the pulp survival. CONCLUSIONS: The primary factors related to pulp healing events after crown fracture appears to be compromised pulp circulation due to concomitant subluxation as well as the stage of root development and fracture depth. For incisors with complicated crown fractures there were two more factors related to pulpal healing-time interval from injury until initial treatment and appropriate emergency treatment.