Finite element analysis of stress distribution in unilateral distal extension partial dentures: a comparison of four attachment designs

The attachment retained RPD with a conventional design offered the lowest stresses applied for the abutment and the residual ridge. OT cap attachment exerts the least stress on the abutments when used in unilateral design RPD, so it is preferable for abutment preservation but contraindicated in weak ridges, however, the double OT cap exerts the highest amount of force on the abutment teeth and could be used with abutments showing perfect periodontal condition.