Korean J Orthod
Published online December 28, 2020
Copyright © The Korean Association of Orthodontists.
Nursel Arici a,*, Berat S. Akdeniz b, Abdullah A. Oz a, Yucel Gencer c, Mehmet Tarakci c, Selim Arici a,**
a Ondokuz Mayıs University, Faculty of Dentistry, Department of Orthodontics, Atakum, 55139, Samsun, Turkey.
b Kırıkkale University, Faculty of Dentistry, Department of Orthodontics, Kırıkkale, Turkey.
c Gebze Technical University, Engineering Faculty, Materials Science and Engineering Department, Cayırova Kampusu, 41400, Gebze, Kocaeli, Turkey.
* First author.
** Corresponding author.
Correspondence to:Prof. Dr. Selim Arici, DDS, MMedSci, PhD
Ondokuz Mayıs University, Faculty of Dentistry, Department of Orthodontics, Atakum, 55139, Samsun, Turkey.
Phone: +90 532 4367923
e-mail: sarici@omu.edu.tr
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Objective: The aim of this study was to decrease the friction between orthodontic brackets and arch wires by using aluminum oxide (Al2O3), titanium nitride (TiN), and chromium nitride (CrN) medical coating materials. The coatings’ resistance to intra-oral conditions was evaluated.
Methods: Stainless steel canine brackets, 0.016’’ round nickel titanium and 0.019 x 0.025’’ stainless steel arch wires were coated with Al2O3, TiN, and CrN using the Radio Frequency Sputtering method. The coated materials were examined using scanning electron microscopy, an x-ray diffractometer, atomic force microscopy, and surface profilometry. A modified tribometer was used to measure the in vitro coefficients of friction (CoFs) of the coated and uncoated materials. Samples were subjected to thermal cycling and in vitro brushing tests, and the effects of simulated intra-oral conditions on the coating structure were evaluated with scanning electron microscopy.
Results: Coating both the metal bracket and nickel titanium arch wire with Al2O3 reduced the CoFs of the bracket arch wire combination (p < 0.01). Coating the bracket and stainless steel arch wire with Al2O3 and TiN resulted in statistically significantly lower CoFs (0.207 and 0.372, respectively) compared to the uncoated bracket and arch wire combination (0.552) (p < 0.01). The frictional wear, thermal, and brushing tests did not deteriorate the overall quality of Al2O3 coatings, but some small peeled areas were evident for TiN coatings and comparatively larger peeling was observed for CrN.
Conclusion: The CoFs between the metal brackets and arch wires could be decreased with Al2O3 and TiN thin film coatings.
Keywords: Thin film coating, Coefficient of friction, Bracket, Wire
Korean J Orthod
Published online December 28, 2020
Copyright © The Korean Association of Orthodontists.
Nursel Arici a,*, Berat S. Akdeniz b, Abdullah A. Oz a, Yucel Gencer c, Mehmet Tarakci c, Selim Arici a,**
a Ondokuz Mayıs University, Faculty of Dentistry, Department of Orthodontics, Atakum, 55139, Samsun, Turkey.
b Kırıkkale University, Faculty of Dentistry, Department of Orthodontics, Kırıkkale, Turkey.
c Gebze Technical University, Engineering Faculty, Materials Science and Engineering Department, Cayırova Kampusu, 41400, Gebze, Kocaeli, Turkey.
* First author.
** Corresponding author.
Correspondence to:Prof. Dr. Selim Arici, DDS, MMedSci, PhD
Ondokuz Mayıs University, Faculty of Dentistry, Department of Orthodontics, Atakum, 55139, Samsun, Turkey.
Phone: +90 532 4367923
e-mail: sarici@omu.edu.tr
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Objective: The aim of this study was to decrease the friction between orthodontic brackets and arch wires by using aluminum oxide (Al2O3), titanium nitride (TiN), and chromium nitride (CrN) medical coating materials. The coatings’ resistance to intra-oral conditions was evaluated.
Methods: Stainless steel canine brackets, 0.016’’ round nickel titanium and 0.019 x 0.025’’ stainless steel arch wires were coated with Al2O3, TiN, and CrN using the Radio Frequency Sputtering method. The coated materials were examined using scanning electron microscopy, an x-ray diffractometer, atomic force microscopy, and surface profilometry. A modified tribometer was used to measure the in vitro coefficients of friction (CoFs) of the coated and uncoated materials. Samples were subjected to thermal cycling and in vitro brushing tests, and the effects of simulated intra-oral conditions on the coating structure were evaluated with scanning electron microscopy.
Results: Coating both the metal bracket and nickel titanium arch wire with Al2O3 reduced the CoFs of the bracket arch wire combination (p < 0.01). Coating the bracket and stainless steel arch wire with Al2O3 and TiN resulted in statistically significantly lower CoFs (0.207 and 0.372, respectively) compared to the uncoated bracket and arch wire combination (0.552) (p < 0.01). The frictional wear, thermal, and brushing tests did not deteriorate the overall quality of Al2O3 coatings, but some small peeled areas were evident for TiN coatings and comparatively larger peeling was observed for CrN.
Conclusion: The CoFs between the metal brackets and arch wires could be decreased with Al2O3 and TiN thin film coatings.
Keywords: Thin film coating, Coefficient of friction, Bracket, Wire