Aim: The aim of this in vivo study was to evaluate the revascularization procedure both in immature and mature teeth with necrotic pulp and open apices, disinfected with triple antibiotic paste followed by inducing blood clot in the root canal. Materials and methods: Fifteen patients were selected who presented with immature and mature permanent teeth with pulpal necrosis and open apices. In the first visit, the root canal was accessed with LA and rubber dam isolation; then the canal was disinfected using triple antibiotic paste containing ciprofloxacin, metronidazole, and clindamycin in the ratio of 1:1:1 and closed with IRM. In the second visit, after administering local anesthesia and isolating with a rubber dam, the triple antibiotic paste was washed out by saline irrigation, and apical papilla beyond the confines of the root canal was stimulated with sterile H file to produce a blood clot. Finally, the access was closed using a double seal with mineral trioxide aggregate (MTA) placed apical to cementoenamel junction and resin bonded cement over the MTA. Radiographic examination and pulp sensibility test was done during the follow-up period of 2,4,6,8 and 10 months. Result: After 10 months follow-up, 10 out of 13 patients showed root development and apical closure. The eight patients out of 13 showed root development, apical closure and lateral thickening of radicular dentin and 2 out of 13 patients showed a positive response to electric sensibility test. Conclusion: Within the limitation of this study, it can be concluded that there is evidence of root development, increase in lateral wall thickness, apical closure and positive response to pulp sensibility test in both mature and immature teeth with necrotic pulp. Clinical significance: The conventional approach for management of teeth with necrotic pulp and the open apex is altered with the possibility of tissue regeneration within the pulp space and continued root development through revascularization procedures. It also re-establishes the vitality in a previously nonvital and necrosed tooth.