Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 5 3 2018 09 15 136 138 Arghavan Tonkaboni Department of Oral Medicine, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Bita Maraghehpour Dentist, MPH, Department of Health Promotion and Community Health Sciences, Texas A&M University Health Science Center, College Station, Texas, United States of America. 2018 10 03 2018 11 20 Oral lichen planus (OLP) is a chronic autoimmune cell-mediated disease affecting mucocotaneous tissues of oral cavity. Recent studies revealed that psychological stress may act as a trigger to initiate clinical symptoms. An 8-year-old girl complaining of oral ulcer, pain and irritation in mouth with onset of 3 months ago, was admitted to oral medicine department. Her medical history was negative except for severe psychological trauma in last 6 months. Intraoral examination showed bluish purple atrophic erosive striations with hyperkeratosis. Pathological study of buccal lesions confirmed OLP diagnosis. As all primary investigations were negative; psychogenic origin was suspected. Although it is rare for a child to have OLP but it should be taken into consideration in differential diagnosis of red and white oral lesions in children. Huge impact of psychological factors in the occurrence of oral diseases have suggested that they should be treated in combination with psychotherapy. https://jcr.tums.ac.ir/index.php/jcr/article/view/248 https://jcr.tums.ac.ir/index.php/jcr/article/download/248/246