Fig. 10

Persistent EPL case following RCT on tooth 21 (apex managed with MTA apexification). a, b) Deep buccal, mesial and palatal probing depths with associated vertical bone loss to the apex were present at baseline. c, d) Following surgical exposure, the granulation tissue was removed and an apicectomy was conducted as the lesion was assumed to be of endodontic origin. d, e) A small perforation was noted as well, which was repaired with a bioceramic putty (Total Fill BC putty). The defect was a contained two-walled defect with a narrow radiographic defect angle <20 ° and so deemed amendable to guided tissue regeneration. f) The defect was filled with a bovine-derived xenograft and collagen membrane (BioOss Collagen and BioGuide). g, h) The immediate post-operative appearance and at one-month review showing resolution of the inflammation with some recession. Due to the increased mobility post-operatively, a splint was placed which was subsequently changed to a lab-made, 0.4 mm, round wire splint, placed palatally for aesthetic reasons