Langerhans cell histiocytosis (LCH) is a rare disease caused by uncontrolled proliferation and accumulation of immature bone marrow-derived myeloid dendritic cells. It is common in the pediatric population under 15 years of age and usually affects bones such as the skull, femur and mandibular body. This study presents the case of a 6-year-old female patient, with a bone lesion in the right mandibular ramus and condyle at an unusual location. A sample of the pathological tissue was taken by intraoral endoscopy to avoid comorbidities and esthetic sequelae. After a joint medical evaluation, the lesion was diagnosed as a monofocal LCH with special site involvement, establishing a single systemic treatment with indomethacin, as opposed to the chemotherapy regimen recommended by the International Histiocyte Society, in order to reduce the adverse effects of the latter. Two months after the beginning of the pharmacological treatment, reosification of the affected area was observed, with no recurrences after the end of the treatment.