Mandibular overdentures stabilized by Astra Tech implants with either ball attachments or magnets: 5-year results

The purpose of this work was to report on the use of implant-stabilized overdentures in the mandible using the Astra Tech implant system with either ball attachments or magnets as the retentive mechanism.

Mandibular overdentures that used ball attachments on 2 implants were provided for 13 edentulous patients; 12 edentulous patients were provided with mandibular overdentures with magnet retention, using 2 implants in 10 patients and 3 implants in 2 patients. Once they were comfortable, the participants were placed on annual recall. Any other visits were initiated by the patients. Detailed records were kept for all visits. At the annual recall the following parameters were monitored: plaque levels, mucosal health, marginal bone levels, and the patients' assessment of the treatment. The patients were followed for 5 years.

There was no statistical difference between the 2 groups for mucosal health and postinsertion maintenance. The magnet group had more abutment surfaces covered with plaque. Statistical analysis of the patients' subjective assessment of their treatment showed that the magnet group was less comfortable and chewing was less effective.

The results indicate that both ball attachments and magnets used on isolated Astra Tech implants in the mandible are viable treatment options. Both attachment mechanisms provided patient satisfaction, although the ball attachments were better in this respect than the magnets.