Pathological migration: an unusual cause of midline diastema.

A 34-year-old female attended the orthodontic department and was concerned with a midline diastema in the lower arch. The diagnosis made was pathological migration owing to the habitual placement of her tongue stud on the incisal edges of her mandibular central incisors, forcing them apart. This article describes the causes of pathological migration, and other possible complications due to oral piercings.