_____________________________________________________________________________________________________ *Corresponding author: Email: nazfor86@gmail.com; International Journal of Research and Reports in Dentistry 2(2): 1-6, 2019; Article no.IJRRD.50735 The Evaluation of the Efficiency of LED Light-curing Units Used in Private Dental Clinics Nazanin Forghani 1* 1 Department of Dental Surgery, Islamic Azad University, Tehran Dental Branch, Iran. Author’s contribution The sole author designed, analyzed, interpreted and prepared the manuscript. Article Information Editor(s): (1) Dr. Hamit Serdar Çötert, Professor, Department of Prosthodontics, Faculty of Dentistry, Ege University, Izmir, Turkey. (2) Dr. Roberta Gasparro, Department of Neuroscience, Reproductive Science and Dental Science, University of Naples Federico II, Naples, Italy. (3) Dr. Betul Yuzbasioglu Ertugrul, Associate Professor, Department of Periodontology, Izmir Demokrasi University, Faculty of Dentistry, Turkey. Reviewers: (1) Muhammad Wasif Saleem, Ziauddin University, Pakistan. (2) Ana Sofia Coelho, University of Coimbra, Portugal. (3) Goo Chui Ling, National University of Malaysia, Malaysia. Complete Peer review History: http://www.sdiarticle3.com/review-history/50735 Received 20 June 2019 Accepted 27 August 2019 Published 07 September 2019 ABSTRACT Background and Aim: The light-cured composites and other restorative materials are quite common in dentistry today. Successful restorations are dependent on the efficiency of the light- curing unit, the intensity of light, and its wavelength. This study evaluated the efficacy of LED light- curing units in private dental clinics in Tehran. Materials and Methods: In this descriptive cross-sectional study, 320 light-curing devices in different private dental clinics were randomly evaluated. The radiometer (light-testing-meter) measured Light intensity, and also dust on the fan and cracks or scratches on the filter were directly observed. Moreover, the age of the device, the frequency of changing the bulbs and satisfaction of the dentist concerning the light-curing unit were recorded in questionnaires. Data were analyzed for Spearman correlation and t-test using SPSS software with p<0.05 as the level of significance. Results: The results showed that the intensity of 53.75% units was more than 300 mW/cm 2 . The power of 30.3% of curing light units was between 200 and 300 mW/cm 2 , and 15.9% had lower than200 mW/cm 2 . The light intensity has a negative relation with the age of the unit, frequency of bulb changing, and scratches on the filter and dust on the fan. Case Study