Jemds.com Case Report J Evolution Med Dent Sci / eISSN - 2278-4802, pISSN - 2278-4748 / Vol. 11 / Issue 06 / May 2022 Page 661 Nonsurgical Management of Periapical Lesions of Mandibular First Molar - Case Report Nelmi Wahyuni 1 , Widi Prasetia 2 1 Department of Vonservative Dentistry Specialist Program, Faculty of Dentistry, Universitas Sumatera Utara, North Sumatera, Indonesia. 2 Department of Conservative Dentistry Specialist Program, Faculty of Dentistry, Universitas Sumatera Utara, North Sumatera, Indonesia. Periapical lesions develop from non-vital teeth. In teeth with non-hermetic root canal filling, the presence of microleakage bacteria will invade the root canal and reach the periradicular area and cause inflammation so that it develops into periapical lesions as a form of failure of root canal treatment. Periapical lesions should be treated with a non-surgical endodontic procedure with a fair success rate. The purpose of this case report was to evaluate conventional endodontics as non- surgical management of teeth with a periapical lesion in previously treated teeth. Case: A 25-year-old female patient came to a private practice with a complaint of cavity in her lower left molar. One month ago, she had a throbbing tooth pain for which she took analgesic medication. The tooth was treated by root canal treatment about 6 years ago. The patient had no history of systemic disease. Case Management: Occlusal Adjustment, non-vital root canal treatment, the core build-up (fibre reinforced composite) and full coverage direct composite restoration. Conclusion: Adequate root canal treatment affects the success of endodontic treatment, in this case, there was very good progress in healing of the periapical lesion. Periapical lesions develop from non-vital teeth. In teeth with non-hermetic root canal filling, the presence of microleakage bacteria will invade the root canal and reach the periradicular area and cause inflammation so that it develops into periapical lesions as a form of failure of root canal treatment. Periapical tissue develops in response to microbial assumption and their by-products that infiltrate the periradicular tissues and activate the host's immune reaction. A dynamic encounter between the host's immune response and microbial infective factors at the interface of the periodontal membrane and infected pulpal tissue results in various periapical lesions. [1,2,3] Periapical lesions should be treated with a non-surgical endodontic procedure with a fair success rate. Microbial elimination or minimization from the pulp system using efficient chemo mechanical preparation can lead to a successful treatment. [1,4,5] The aim of this case report is to evaluate conventional endodontics as non-surgical management of teeth with a periapical lesion. Corresponding Author: Dr. Widi Prasetia, Department of Conservative Dentistry Specialist Program, Faculty of Dentistry, Universitas Sumatera Utara Jl. Alumni no. 2 Medan 20155, North Sumatera, Indonesia. E-mail: widi.prasetia@usu.ac.id DOI: 10.14260/jemds.v11i6.135 How to Cite This Article: Wahyuni N, Prasetia W. Nonsurgical management of periapical lesions of mandibular first molar - case report. J Evolution Med Dent Sci 2022;11(06):661- 664, DOI: 10.14260/jemds.v11i6.135 Submission 15-04-2022, Peer Review 12-05-2022, Acceptance 18-05-2022, Published 30-05-2022. Copyright © 2022 Nelmi Wahyuni et al. This is an open access article distributed under Creative Commons Attribution License [Attribution 4.0 International (CC BY 4.0)] INTRODUCTION