Effect of Different Materials of Primary Telescopic Crowns on The Frictional Fit of Pekkton Partial Denture Frameworks in Kennedy Class I

Abstract

Objectives: This research was carried out to evaluate the friction fit (FF) of secondary telescopic crowns made of polyetherketone ketone (PEKK) in combination with primary crowns made of two different dental materials. Materials and methods: It is an in-vitro study where (6) Removable partial denture frameworks together with secondary crowns were milled from polyetherketone ketone (PEKK). Afterwards, (48) primary crowns were fabricated group (A): (24) PEKK-crowns were milled from Pekkton® blank, group (B): (24) zirconia-crowns were milled from a pre-sintered zirconium-dioxide blank. Friction fit (FF) was measured in a pull-off test (6 pull-off/specimen). Maximum tensile loads needed to dislodge the framework from the cast were calculated in Newtons. The acquired data were then tabulated and statistically analysed. Results: It was found that group (A) recorded statistically significant higher friction fit mean value (10.40±1.49) than group (B) (6.78±1.05) as indicated by t-test (P ≤ 0.05). Conclusion: PEKK primary crowns showed better friction fit than zirconia one in conjunction with PEKK framework in kennedy class I telescopic partial denture.