An In vitro study to evaluate the frictional characteristics and surface topography of two different arch wires coated with silver nano particles using passive self ligating brackets

Surya, R Krishnan (2018) An In vitro study to evaluate the frictional characteristics and surface topography of two different arch wires coated with silver nano particles using passive self ligating brackets. Masters thesis, Sree Mookambika Institute of Dental Sciences, Kulasekharam.


Download (4MB) | Preview

Download (400kB) | Preview


INTRODUCTION: Orthodontic tooth movement during space closure may occur in two different types of mechanics: sliding mechanics and frictionless mechanics. In sliding mechanics, friction is generated by the relative motion between archwire and the bracket, sliding mechanics is widely used in fixed appliance therapy. The rapid progress in the field of biomedical engineering has resulted in various surface modification methods to improve the overall performance of the biomedical metallic materials. Coating the orthodontic metallic wires on their surfaces using different materials and techniques are among the strategies that have shown to improve both the biological as well as mechanical properties. The present study involved the coating of rectangular TMA and stainless steel archwires with silver nanoparticles, via the physical vapor deposition – DC magnetron sputtering method. The objective of the study is to reduce the frictional values of the archwires during the sliding mechanics for faster tooth movement, shorter treatment duration and to prevent root resorption. This study is also done to evaluate the surface characteristics of the silver nanoparticle coated archwires, in combination with passive self-ligating stainless steel brackets having MBT prescription so as to ascertain the relation of the surface quality of the archwires with that of the friction that is being generated during the procedure. METHODS: The two types of orthodontic metallic archwires were coated with silver nano particle using physical vapor deposition method –DC magnetron sputtering and thickness measured using profilometer. All frictional tests were conducted in a dry state on Instron 3345 testing machine. Friction testing was done using passive self-ligating stainless steel brackets, MBT prescription. Surface characteristics was tested by subjecting the samples to scanning electron microscopy, prior to and after the friction testing. The sliding resistance and surface characteristics of the AgNP coated and control archwires were analyzed. RESULTS: The measurements were obtained for the mean frictional values for the uncoated stainless steel, coated stainless steel, uncoated TMA and coated TMA orthodontic archwires. It clearly indicates that there is reduction in frictional values for the AgNP coated TMA archwires when compared with uncoated counterparts and also with the AgNP coated stainless steel, archwires. The surfaces of the AgNP coated TMA and stainless steel archwires were smooth and even. The uncoated TMA surfaces showed rough surface as concurrent with other studies. No significant surface alterations upon SEM evaluations of friction tested archwires coated with AgNP was found. CONCLUSION: The AgNP coated TMA archwires showed statistically significant difference in their frictional values, when compared with the uncoated archwires. It could be recommended for improved frictional properties, better surface characteristics to be used in sliding mechanics. No significant reduction in the frictional values of AgNP coated stainless steel archwires for both dimensions used in the study was noted, instead higher frictional values were obtained which indicates that there is no need to coat stainless steel archwires with AgNP.

Item Type: Thesis (Masters)
Uncontrolled Keywords: Silver nanoparticle coated archwires ; friction ; passive self-ligating brackets.
Subjects: DENTAL > Orthodontics and Dentofacial Orthopedics
Depositing User: Subramani R
Date Deposited: 14 Oct 2018 17:10
Last Modified: 14 Oct 2018 17:10

Actions (login required)

View Item View Item