Occurrence of pulp canal obliteration after luxation injuries in the permanent dentition

TLDR

Pulp canal obliteration (PCO) is considered a sequela of revascularization or reinnervation following pulp injury. The study examined 637 luxated permanent incisors to identify factors influencing PCO development. Among the 637 injured incisors, 15% showed partial PCO (1% total), with higher incidence in teeth with incomplete root formation and in extrusion, lateral luxation, or intrusion; orthodontic band/resin splints further increased PCO risk, while discoloration and pulp sensibility were largely unchanged except for a lower perception threshold after lateral luxation.

Abstract

Abstract A material of 637 concussed, subluxated, extruded, laterally luxated and intruded permanent incisors was analyzed with respect to factors influencing the development of pulp canal obliteration (PCO) after injury. A total of 96 (15%) developed partial PCO; 9 of these (1% of the total material) went on to develop total PCO. Only 2 teeth exhibited yellow discoloration of the clinical crown and 1 showed grey discoloration. Sensibility to electrometric pulp testing of the teeth with PCO was not significantly different from sensibility of contralateral homologues at the final examination (except for after lateral luxation, where the teeth with PCO had a significantly lower perception threshold). PCO was significantly more frequent among teeth with incomplete root formation than in teeth where root formation was completed. Extrusion, lateral luxation and intrusion showed more frequent occurrence of PCO than did concussion and subluxation. Moreover, the use of orthodontic band/resin splints significantly increased the occurrence of PCO, presumably due to the additional trauma of forceful placement and cementation of orthodontic bands in contrast to the relatively passive placement of an acid‐etch/resin splint. Based on previous and present clinical and radiographic findings concerning pulp response to luxation injuries, it is suggested that PCO is a sequel to revascularization and/or reinnervation of a damaged pulp after injury.