. 🦷The RPI system is a combination of occlusal rest (R) distal guide plate (P) and gingivally approaching I bar clasp (I) used primarily with mandibular distal extension saddles. . 🦷The RPI system is designed to allow vertical rotation of a distal extension saddle into the denture-bearing mucosa under occlusal loading without damaging the supporting structures of the abutment tooth 🦷As the saddle is pressed into the denture-bearing mucosa . 🦷 The denture rotates about a point close to the me