Fig. 2

A Periapical radiograph of teeth #11 and #21 after trauma. The roots were completely formed. Multiple horizontal fractures in the middle third of the roots of teeth #8 and tooth #9 were evident. B Preoperative periapical radiograph before REPs. C Postoperative periapical radiograph after completion of REPs. D Postoperative periapical radiograph at the 1-month follow-up. No radiolucent lesion developed at the fracture line. E Postoperative periapical radiograph at the 6-month follow-up. Progressive healing of the horizontal root fracture by formation of hard tissue between fragments of tooth #21. F Postoperative periapical radiograph at the 14-month follow-up. More calcified in the fracture lines and root canal space of apical fragment of both teeth. G Postoperative periapical radiograph at the 25-month follow-up. Further healing of horizontal root fracture by formation of hard tissue, and calcification in the apical fragments of both teeth. H Postoperative periapical radiograph at the 36-month follow-up. The formation of calcified tissue continued between fragments of tooth #21 and coronal part of tooth #11. Partial canal obliteration is also evident in the coronal fragment. There is near complete calcification of the pulp space in the apical fragment. There was no evidence of a periapical lesion for either tooth