Cases were selected from years 2000-2005. Selected x-rays concerned patients whose treatment had included extraction of first upper and lower premolars. These patients were also lacking any history of craniofacial anomalies or dental illness.
Las radiografías fueron seleccionadas de pacientes cuyo tratamiento fue con extracciones de los primeros premolares superiores e inferiores y sin historial de alguna anomalía craneofacial, ni patologías dentales.