Tarnish and corrosion with the use of intraoral magnets.

Intraoral magnets are small enough and provide sufficient retentive forces to be used in various prosthodontic procedures. This study described 25 patients with 60 magnetic attachments. All implant abutments gave evidence of tarnish, as did 68% of the magnetic keepers in patients with natural teeth. Corrosion was found in 41.7% of the magnetic keepers. Although 88% of the patients were satisfied at 3 months, only 28% were satisfied at 2 years. Rare earth magnets probably can be used for retention of removable prostheses. However, the magnets are likely to tarnish and corrode, making them unacceptable for use intraorally at this time.