In the domains of dentistry and regenerative medicine, the application of platelet concentrates has become very common.  Recent years have seen a significant increase in interest in injectable platelet-rich fibrin (I-PRF), in the field of bone tissue engineering. Etidronic acid (HEDP), a relatively weak chelator, has been licensed for clinical use named as dual rinse. A salt of 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) was commercialized a few years ago (Dual Rinse® HEDP, Medcem Weinfelden, Switzerland).

Up to date, there is no evidence of single-visit pulp and bone regenerative therapy using HEDP and I-PRF for immature permanent teeth with complete buccal bone loss after traumatic dental injury.

So, this case report aimed to present a successful regenerative endodontic treatment (REP) performed in a single visit for an immature maxillary right central incisor as a sequela of traumatic injury one year earlier. A 9-year-old female patient was referred for the management of the traumatized maxillary right central incisor (#11). The chief complaint was severe pain related to maxillary centrals. The extraoral clinical examination revealed no abnormal findings. Intraorally, tooth #11 revealed a complicated crown fracture and previously accessed pulp chamber. A sinus tract was observed on the labial mucosa at the level of the coronal third of the root. Clinical examination revealed severe tenderness to percussion and palpation, with a negative response to thermal (cold) pulp testing. Radiographic examination, including periapical imaging and cone beam computed tomography (CBCT), revealed a large periapical lesion at the apex of tooth #11, with complete loss of the buccal cortical plate. A diagnosis of pulp necrosis with symptomatic apical periodontitis was made.  Hence, a single-visit REP was done using I-PRF that was injected beyond the apex, and the root canal was disinfected using HEDP mixed with NaOCl. After 12 month follow up, clinical and radiographic examinations showed that the tooth became asymptomatic, responded to sensibility tests, and the periapical pathosis healed with complete buccal bone regeneration. It was concluded that regenerative endodontic treatment can be done in a single visit.