Aims and background: The success of endodontic treatment in open apex teeth depends on the establishment of an ideal apical barrier so that apical canal space between the periodontium and the root canal system is filled. Biodentine is a calcium silicate-based cement having several advantages over mineral trioxide aggregate (MTA), glass ionomer cement (GIC), and calcium hydroxide in the treatment of teeth with open apices. Orthograde delivery of biodentine is technique-sensitive and requires multiple radiographs for verification, as well as retrograde placement of biodentine requires surgical intervention. To use the advantages of biodentine and to overcome the disadvantages of placement techniques, an innovative technique was done to obturate the tooth with an open apex using a custom-fit prefabricated BioRoot inlay in this case report. Case description: In the present case, biodentine has been used as a BioRoot inlay to overcome the disadvantages of various management options of open apex with parallel dentinal walls. BioRoot inlay is an intraradicular custom-made prefabricated restoration which provides the three-dimensional seal of the root canal space and promotes an apical barrier formation in a wide-open apex. This BioRoot inlay, placed passively in the canal, had a good seal laterally and apically along with the Biodentine as sealer forming a monoblock. This sealer helps in sealing milder discrepancies between the plug and the root, providing a three-dimensional seal which had resulted in good healing of periradicular bone. Conclusion: Biodentine, when used as BioRoot inlay, has been shown to induce faster periapical healing. It provides promising results when used in open apices with parallel walls. It establishes three-dimensional obturation and proper apical seal, which promotes effective root-end induction. Clinical significance: It can be considered as the effective and definitive alternative for nonsurgical and surgical approaches to treating open apex.