CANTILEVER IN PROSTHESIS: EVALUATION OF RELATION BETWEEN THICKNESS AND LENGTH WITH LOADING IN Ni-Cr BARS
HUMBERTO GENNARI *
Department of Dental Materials and Prosthodontics, Araçatuba Dental School, University of State of Sao Paulo (UNESP), Araçatuba, Sao Paulo, Brazil.
MARCELO COELHO GOIATO
Department of Dental Materials and Prosthodontics, Araçatuba Dental School, University of State of Sao Paulo (UNESP), Araçatuba, Sao Paulo, Brazil.
PAULO RENATO JUNQUEIRA ZUIM
Department of Dental Materials and Prosthodontics, Araçatuba Dental School, University of State of Sao Paulo (UNESP), Araçatuba, Sao Paulo, Brazil.
JOSÉ VITOR QUINELI MAZARO
Department of Dental Materials and Prosthodontics, Araçatuba Dental School, University of State of Sao Paulo (UNESP), Araçatuba, Sao Paulo, Brazil.
CRISTINA RAMOS DA SILVA
Department of Dental Materials and Prosthodontics, Araçatuba Dental School, University of State of Sao Paulo (UNESP), Araçatuba, Sao Paulo, Brazil.
*Author to whom correspondence should be addressed.
Abstract
Aim: The aim of this study was to evaluate the relation between the applied force and deformation in Nickel-Chromium-Molybdenum-Titanium alloy bars with different cantilever thicknesses and lengths in a universal mechanical testing machine.
Methods: Sixty metallic Nickel-Chromium-Molybdenum-Titanium alloy (Ni-Cr-Mo-Ti) bars, 40 mm in length, were divided into 4 groups with thicknesses of 4.0, 3.5, 3.0, and 2.5 mm. All bars were submitted to compressive loading of 200 kgf in a universal mechanical testing machine at a frequency of 0.5 mm per minute. The loads were applied automatically and gradually in a cantilever length of 10, 15 and 20 mm until alloy fatigue. The method was controlled by software to indicate the relation between the applied force and deformation. Data were submitted to an analysis of variance and Tukey`s test.
Results: The analysis of variance revealed statistically significant differences in the individual evaluation of thickness and length and also in the relation between the thickness and length (p<0.01).
Keywords: Dental cast, alloys, mechanical stress, bite force, dental prosthesis, implant- supported