Regenerative Endodontic Treatment (RET) can be used as an alternative to apexification treatment in immature permanent tooth having irreversible pulpitis and nonvital teeth with or without apical periodontitis. In this case report, RET was used to treat an immature permanent maxillary central incisor with apical periodontitis. Triple antibiotic paste (TAP) as intracanal medicament was placed in root canal for 4 weeks. Ethylenediaminetetraacetic acid (EDTA) was used as final irrigant. As a scaffold, Platelet-rich fibrin (PRF) was applied. Biodentine was applied upon PRF, and GIC and composite was placed to restore the teeth. Teeth showed no signs and symptoms of pain and gradual periapical healing was seen during three, six and twelve months follow-up periods, also dentinal thickening and reduced PLD widening was seen during six and twelve months follow-up periods; and pulp sensibility tests using electric pulp test showed no results.