Influence of Liquid Lubrication on the Screw-Joint Stability of Y-TZP Implant Abutment Systems
Mariana de Almeida Basílio1, Filipe de Oliveira Abi-Rached1, Luis Eduardo Butignon2
1Department of Dental Materials and Prosthodontics, UNESP-Univ Estadual Paulista, Araraquara School of Dentistry, Araraquara, São Paulo, Brazil.
Purpose:
To evaluate the effectiveness of abutment screws coated with liquid Vaseline on the screw-joint stability of yttria-stabilized tetragonal zirconia (Y-TZP) abutment systems.
Materials And Methods:
Forty Y-TZP prefabricated abutments, 20 Neodent and 20 Bionnovation, were tightened to 20 Ncm on their respective external hexagon implants, and divided into four groups (n = 10) according to the screws: coated with Vaseline or uncoated. The removal torque (RT) value of the abutment screw was measured before and after loading. A cyclic loading (0.5 × 106 cycles; 15 Hz) between 11 and 211 N was applied. Means were compared using a repeated-measures ANOVA (α = 0.05).
Results:
There was no significant difference between coated and uncoated screws (p = 0.822). Significant differences were found between the abutment systems (p < 0.001). There was a significant effect of cyclic loading (p < 0.001).
Conclusions:
Coated and uncoated screws presented similar effectiveness in maintaining preload.
Clinical Relevance:
The liquid lubricant used in this study does not influence the stability of Y-TZP single-implant restorations.
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