The initial retention of implant-supported removable partial
dentures(ISRPD) is unknown. the purpose of this in vitro study was
to compare maximum dislodging forces of distal extension
mandibular ISRPD with three different clasp design. a stimulat
ed
class 1 partially edentulous mandible was prepared with two
implant in the first molar regions and two metal ceramic on distal
abutments. Fifteen bilateral distal extension frameworks was
fabricated with three different clasp design (Akers, I bar clasp ,no
clasp),each specimen was subjected to three type of retention
pulls ( main ,unilateral ,posterior pulls) five time with universal
testing machine.