Taper Angle of Telescopic Removable Partial Denture: Finite Element Study

Methods: Three identical mandibular stone models representing Kennedy class É with first premolars as the last standing abutments were used. The first premolars of the three models were ground to the same height (6mm) but with different taper angles (0°, 6° and 12°). Telescopic crown retained RPDs were constructed on each model exhibiting the same design except the taper angle of telescopic crown. Each model with the overlying denture were duplicated, boxed and poured to obtain a stone box. The stone box was C.T. scanned to be used for finite element model construction using ANSYS software program. Tissue-ward forces of 300N were applied on the 2nd premolar, 1st and 2nd molars of the finite element models. The stresses induced in the abutment teeth and the residual ridge were calculated and analyzed for each model.

Results: The results revealed an increase in the stresses induced to the residual ridge and a decrease in the stresses induced to the abutment teeth when the taper angle of the telescopic crowns retaining the RPDs was increased.

Conclusion: It was thus concluded that increasing the taper angle of telescopic crowns retaining distal extension RPD provides a stress breaking effect on abutment teeth.

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