A comparative study to evaluate retention of full metal crowns cemented with various luting agents with and without application of dentine conditioners: An in vitro study

Aim: The aim of the study is to assess the effect of dentin conditioners and luting cements on the retention of full metal crowns. Materials and Methods: Sixty recently extracted caries free molar teeth were prepared using airotor hand piece mounted to a surveyor with a custom made jig, to obtain a standardized 26° total convergence and 4 mm of axial height. Individual crowns were fabricated using base metal alloy. Thus prepared specimens were divided into six groups: 1) Two groups with no dentin conditioning (Control groups A and B), 2) Two groups, dentin conditioned with 10% polyacrylic acid conditioner (First test groups C and D), and 3) Two groups, dentin conditioned with 17% Ethylenediaminetetraacetic acid (EDTA) (Second test groups E and F). Groups A, C, and E were cemented with conventional glass ionomer whereas Groups B, D, and F were cemented with resin-modified glass ionomer. De-cementation was done using universal testing machine at a cross head speed of 1 mm/min after 48 hours of cementation. The obtained results were analysed using One-way analysis of variance (ANOVA) and Post hoc test. Results: The mean retentive (tensile) strength of Group A specimens was 2.26 ± 0.15 MPa, Group B specimens was 2.71 ± 0.15 MPa, Group C specimens was 12.26 ± 0.67 MPa, Group D specimens was 14.28 ± 1.47 MPa. Similarly, Group E specimens was 5.23 ± 0.62 MPa, and Group F specimens was 7.36 ± 0.51 MPa. Conclusion: Within the limitations of the study, retentive (tensile) strength required to dislodge the metal crowns was higher with the combination of resin-modified glass ionomer luting cement and 10% polyacrylic acid dentin conditioner