In this case report occurrance of cavitation on the lingual enamel surfaces of teeth after orthodontic direct bonding a canin to canin lingual retainer is presented and possible reasons which might play a role in their formation was investigated by “SEM” and “electron micro-probe analyzer”. Although the morphologic structure is normal, a mineral loss is detected and it is thought that an easier dissolution of enamel is occured by the penetration of saliva and plaque microorganisms throughout the enamel-resin junction.

Keywords: Retention, Cavitation, Hypocalcification