Effect of screw hole filling on retention of implant crowns.

The screw access channels of 15 degrees angled Esthetic Abutments (Brånemark System) were either (a) completely filled with a vinyl polysiloxane impression material (Memosil), (b) partially filled with Memosil or (c) had lower portion filled with Memosil and the remainder with composite resin. The force required to remove a temporarily cemented restoration was measured. The removal force was significantly reduced with the channel completely filled with Memosil compared to those partially filled with Memosil (p<0.01) or with composite resin placed over Memosil (p<0.01). The method selected to fill the screw access channel of an implant abutment can be a significant factor affecting retention of a cemented restoration.