Analysis of residual stress and hardness in pre-bent plates areas by the manufacturer, manually bent plate areas and plate areas without bent used rigid internal fixation

• Grant number: 12/04926-2
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2012
• End date: August 31, 2013
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal Investigator: Marcelo Marotta Araujo
• Grantee: Marcelo Marotta Araujo
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

Implant for internal fixation used in maxillo-facial skeleton in the form of plates, screws or pins stabilize fractures and sustain the loads, whether or not physiological. The plates applied to these areas need to be able not only to resist to the deformation forces intensively applied, but should also withstand cyclic loading that is chronically applied until the time when the bone is regenerated. The plates used in maxillofacial surgery today are made of titanium and can be purchased pre-bent by the manufacturer or can be manually bent. However, it has been observed in clinical practice that the performance of manual bending of the material can lead to fatigue and breakage of the system, often leading the patient to another surgery to remove and installing new material to reach the desired surgical result. Thus, the objective of this study is to analyze using the Vickers hardness test and x-ray diffraction test respectively, the hardness and residual stress in pre-bent areas by the manufacturer, manually bent areas and areas without bent. This study will have three groups (I-region of the fold prefabricated 90 degrees; II-manual folding in the region of 90 degrees; region without bending-III) each containing a titanium plate 10 folded pre-feed system 10 mm 1.5 mm Toride (Toride Industria e Comercio Ltda. - Mogi Mirim, São Paulo - Brazil). According to the manufacturer's specifications plates are commercially pure titanium, grade II. All materials will undergo to hardness analysis, by means of the Vickers by light microscopy, and the residual stress analysis by x-ray diffraction. The data will be analyzed statistically. (AU)