The present article describes a clinical case of an adult patient using an orthodontic appliance, who returned to the dental office after the placement of orthodontic mini-implants, complaining of aphthas. By means of clinical and case history evaluation the diagnosis of primary herpetic gingivostomatitis was reached. The treatment was prescription of an antiviral agent associated with a chlorhexidine-based oral mouthwash. One week after their onset, there was complete regression of the lesions.