Abstract: Objective: To evaluate the clinical efficacy and influencing factors of long-term calcium hydroxide medication combined with iRoot BP Plus apical barrier technique in treating chronic apical periodontitis in permanent teeth with open apices. Methods: A retrospective study was conducted on 74 teeth treated at Suzhou Stomatological Hospital from January 2021 to December 2023. All cases received Vitapex for 1-35 months, followed by apical barrier treatment using iRoot BP Plus upon lesion control or calcified barrier formation. Follow-up ranged from 12 to 47 months. Clinical parameters including age, sex, tooth position, diagnosis type, medication duration, lesion area, apical foramen diameter, and PAI score were analyzed in relation to treatment outcomes. Results: The total effective rate was 97.3%, with a healing rate of 82.4%. Age, preoperative lesion area, follow-up duration, tooth position, and diagnosis type were significantly associated with outcomes (P<0.05), while sex, medication duration, and apical foramen diameter were not (P>0.05). Conclusion: This treatment approach is clinically effective and particularly suitable for younger patients with non-cystic premolars and smaller lesions. Extended follow-up may improve outcomes.

Key words: calcium hydroxide, apical barrier technique, chronic apical periodontitis, open apex, bioceramic material