Prosthetics – Overdenture Abutments
- are recommended for the mandible only. Free standing implants in the maxilla have an extremely poor prognosis.
- will give stability and retention to the denture but only limited support. A meso bar or fixed bridge will therefore always be superior. The overdenture abutment is therefore selected for primarily financial reasons, ie. it is usually a compromise treatment.
- should be placed as close to the mental foramen as possible to maximise lateral stability and minimise “rocking”, ie. ideal implant placement is not the same as one would choose for a doldar bar-type restoration.
- length is critical to the success or failure of the restoration. The length must be such that the plastic clip, when applied, rests gently on the tissue.
An important detail regarding the use of Overdenture Abutments:
WRONG: Implants don’t have to be parallel but the clips MUST be (Clips that aren’t parallel have high initial retention but in a matter of months the retention is lost altogether).
Overdenture Abutments (OB) are available in lengths: 2mm, 3mm, 4mm, 5.5mm, 7mm and (OBA) are available in 3mm, 4mm, and 5.5mm. The ideal transmucosal height depends on the tissue depth. This can be measured with a Tissue Depth Gauge (I-DG-A) available from Southern Implants.