Influence of topical fluoride treatment on the mechanical properties and surface topography of translucent composite orthodontic wires

Document Type : Original Article

Authors

1 Department of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Mansoura, Egypt

2 Department of Orthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt

Abstract

Objective: The aim of this study was to determine the effects
of a fluoride prophylactic agent on the mechanical properties and
surface quality of a preformed round translucent composite
archwire comparing it with a nickel-titanium and a multistranded
stainless steel wires.
Materials and Methods: The wires were immersed in either
an acidulated fluoride solution (APF) or distilled water (control)
for 1.5 hours at 37o C. Flexural modulus of elasticity (E) and yield
strength (YS) of the wires were measured using a 3-point bending
test in a Universal Testing Machine. Springback ratio (YS/E) was
calculated for each wire. The influence of fluoride treatment on
properties of the wires was statistically analyzed using a student's
t-test at ; = 0.05. Surface changes were observed with a scanning
electron microscope.
Results: Fluoride treatment produced a statistically significant
reduction in E, YS and YS/E of the composite wire (P < 0.05). In
addition, a significant decrease in E of Ni-Ti wire was found after
exposure to fluoride, comparing it with distilled water control
treatment. On the other hand, no significant effect of fluoride
treatment was found on YS and YS/E of Ni-Ti wire and also on
the studied properties of the multistranded stainless steel wire
(p > 0.05). Corrosive changes in surface topography were observed
after exposure to the fluoride agent, which were more pronounced
with the composite wire.
Conclusions: The results suggest that using topical fluoride
agent with translucent composite wire could decrease mechanical
properties and might damage surface of the wire, which potentially
contribute to prolonged orthodontic treatment.

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