The Astra Implant System (AIS) is a biologically sound and simple way
of providing stability for the complete lower denture where anatomical
changes have made retention, stability and comfort difficult to achie
ve. An ongoing clinical study has been undertaken where 20 patients ha
ve been provided with magnet retained overdentures using this implant
system. This represented a total of 70 implants placed. Seven implants
were removed from four patients (three at exposure, one infection). T
he remaining implants have been followed up for 12 to 25 months and ar
e considered to have achieved successful osseointegration. All the pat
ients in the study are successfully wearing a lower denture retained b
y magnets. The overall success rate for the implants placed is 90% but
if implants less than 9 mm in length are excluded from the results th
en the success rate is 97.7%.