de la Macorra, José, School of Dentistry, Complutense University. Madrid., Spain



Corresponding: Facultad de Odontología, Universidad de Concepción, Chile. Roosevelt 1550, Concepción, Chile. Phone +56-41-2204232 - Fax +56-41-2243311- Mailbox 160-C, Concepción, Chile. E-mail journal@joralres.com.