Effect of fluoride mouth rinses on various orthodontic archwire alloys tested by modified bending test: an in vitro study.
OBJECTIVE
Fluorides can cause corrosion and degradation in mechanical properties of commonly used archwires by forming hydrofluoric acid HF and causing disruption of protective titanium oxide layer. Hence, the aim of this study was to assess the change in load deflection characteristics of Ni-Ti, Cu Ni-Ti, S.S, and β-Ti wires on immersing in fluoride mouth rinses of two types- Phosflur and neutral NaF mouth rinse utilizing a modified bending test and comparing it to control.


METHODS
Round preformed wires were immersed in 10 ml of control and test solution (Phosflur and S-Flo mouth rinse) for 1.5 hours and incubated at 37°C. Modified bending test was carried out to evaluate load-deflection characteristics of different wires using Instron. Analysis of variance (ANOVA) was applied to determine if statistically significant difference exist among the mean load values obtained at various deflections in control and test solutions.


RESULTS
There was no statistically significant reduction in load deflection characteristics of Ni-Ti, copper Ni-Ti, β-Ti, and S.S wires on immersing in Phosflur mouth rinse and neutral sodium fluoride mouth rinses as compared to control at 2.5 and 1 mm of deflection in unloading phase.


CONCLUSIONS
Phosflur and a neutral sodium fluoride mouth rinse did not affect the mechanical bending properties of Ni-Ti, copper Ni-Ti, B-Ti, and SS wires in in vitro conditions.
Department of Orthodontics & Dentofacial Orthopedics, Goa Dental College & Hospital, Bambolim, Goa, India.
Kamna
K
Srivastava
Pavan Kumar
PK
Chandra
Nandini
N
Kamat
D002327:Cariostatic Agents / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry*; D003799:Dental Stress Analysis / Q000295:instrumentation; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D009067:Mouthwashes / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D009969:Orthodontic Wires; D018583:Pliability; D012969:Sodium Fluoride / Q000737:chemistry; D013193:Stainless Steel / Q000737:chemistry; D013314:Stress, Mechanical; D013696:Temperature; D013997:Time Factors; D014025:Titanium / Q000737:chemistry
D002327:Cariostatic Agents; C415948:Copper NiTi; D003722:Dental Alloys; D009067:Mouthwashes; C023988:beta titanium; C040654:titanium nickelide; D013193:Stainless Steel; D003300:Copper; D009532:Nickel; D012969:Sodium Fluoride; D014025:Titanium; D005459:Fluorides