Push-out force evaluation of titanium cylinders attached to implant supported immediate provisional heat-polymerized acrylic resin with various relining material types and thicknesses.

Purpose: To compare the laboratory push-out forces on titanium cylinders attached to immediate provisional heat-polymerized acrylic resins using different relining material types in varying thicknesses, and to investigate the fracture types.

Methods: Heat-polymerized acrylic discs (Futura Basic Hot) (n= 105) were manufactured with artificial first molar teeth centered in each specimen (diameter: 24 mm, height:10 mm). Discs were drilled to create 6 mm, 8 mm and 10 mm diameter holes, corresponding to connection thicknesses of 1 mm, 2 mm, and 3 mm, respectively, around the 4 mm diameter titanium cylinders (n= 35/group). Each group was divided into five relining resin subgroups: Futura Basic Hot, Ufi Gel Hard, Qu-resin, Quick Up, and Pattern resin (n= 7/subgroup). Titanium cylinders were fixed into the holes, and the gaps were filled with relining resins. After 5,000 thermal cycles, a push-out test was performed (1 mm/minute). Data were analyzed with two-way ANOVA and Tukey post hoc tests (P= 0.05) and failure types were classified.

Results: Resin types, connection thicknesses, and their interaction significantly affected the push-out forces (P< 0.05). Futura Basic Hot showed the lowest push-out forces (171 ± 39 N, 317 ± 131 N, and 144 ± 78 N, for 1 mm, 2 mm, and 3 mm connection thickness groups, respectively) (P< 0.05). Qu-resin and Pattern resin had the highest push-out force for 1 mm (1,235 ± 375 N and 1,576 ± 272 N, respectively) and 3 mm (1,333 ± 127 N and 1,406 ± 82 N, respectively) connection thicknesses. Qu-resin, Ufi Gel Hard, Pattern resin, and Quick Up (2,065 ± 342 N, 1,835 ± 630 N, and 1,626 ± 106 N, 1,501 ± 312 N, respectively) all performed well for 2 mm (Plt; 0.05). 2 mm connection thickness resulted in the highest push-out forces, except for Pattern resin. Qu-resin and Pattern resin are suitable for all connection thicknesses, while Ufi Gel Hard and Quick-Up perform optimally with connection thickness of 2 mm. Futura Basic Hot results in weaker push-out forces for implant-supported immediate provisional hybrid prostheses (IPHPs) fixation. 2 mm connection thickness is generally recommended for improved push-out force.

Clinical significance: The choice of relining resin material and connection thickness significantly influence the push-out force on titanium cylinders attached to IPHPs. Selecting appropriate resin material types and thicknesses can enhance the long-term stability and clinical performance of IPHPs, reducing the risk of fractures during implant osseointegration period.