Shaymaa Elsaka1,2, Ali Hassan3,4, Amr Elnaghy5. 1. Department of Dental Biomaterials, Faculty of Dentistry, Mansoura University, Mansoura, 35516, Egypt. shaymanaghy@mans.edu.eg. 2. Department of Restorative Science, Alfarabi Private College of Dentistry and Nursing, Jeddah, Saudi Arabia. shaymanaghy@mans.edu.eg. 3. Department of Restorative Science, Alfarabi Private College of Dentistry and Nursing, Jeddah, Saudi Arabia. 4. Department of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. 5. Department of Endodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Abstract
OBJECTIVE: The purpose of this study was to evaluate the effect of simulated gastric acid solution on surface topography and bending properties of esthetic coated nickel-titanium (NiTi) archwires. MATERIALS AND METHODS: Three brands of as-received white-coated superelastic NiTi upper archwires were used in this study: Dany, Perfect, and Nitanium. Uncoated metallic areas for each white-coated NiTi archwire were used for comparison with the coated areas. The specimens for each archwire were divided into two groups according to coating as follows: Group A, uncoated, and group B, coated. Then, each group was further subdivided into two subgroups according to the immersion medium as follows: Subgroup 1, immersed in artificial saliva, and subgroup 2, immersed in simulated gastric acid. Surface roughness, surface morphology, and three-point bending test were performed. The data were analyzed statistically using ANOVA and Tukey test. RESULTS: The archwires immersed in simulated gastric acid solution showed significantly higher surface roughness and lower forces on loading and unloading than the archwires immersed in artificial saliva (P < 0.001). Perfect archwire showed significantly the highest surface roughness compared with Dany and Nitanium archwires (P < 0.001). The uncoated archwires showed higher loading and unloading forces compared with coated archwires for all groups (P < 0.001). Nitanium archwire showed the lowest loading and unloading forces at different deflections (P < 0.001). CONCLUSIONS: The simulated gastric acid solution decreased considerably the amount of force applied at a given deflection. The loading-deflection and surface roughness properties of coated archwires were affected by the type of coating material. CLINICAL RELEVANCE: The impact of gastric acids on surface and mechanical properties of orthodontic archwires depend on type of coating materials.
OBJECTIVE: The purpose of this study was to evaluate the effect of simulated gastric acid solution on surface topography and bending properties of esthetic coated nickel-titanium (NiTi) archwires. MATERIALS AND METHODS: Three brands of as-received white-coated superelastic NiTi upper archwires were used in this study: Dany, Perfect, and Nitanium. Uncoated metallic areas for each white-coated NiTi archwire were used for comparison with the coated areas. The specimens for each archwire were divided into two groups according to coating as follows: Group A, uncoated, and group B, coated. Then, each group was further subdivided into two subgroups according to the immersion medium as follows: Subgroup 1, immersed in artificial saliva, and subgroup 2, immersed in simulated gastric acid. Surface roughness, surface morphology, and three-point bending test were performed. The data were analyzed statistically using ANOVA and Tukey test. RESULTS: The archwires immersed in simulated gastric acid solution showed significantly higher surface roughness and lower forces on loading and unloading than the archwires immersed in artificial saliva (P < 0.001). Perfect archwire showed significantly the highest surface roughness compared with Dany and Nitanium archwires (P < 0.001). The uncoated archwires showed higher loading and unloading forces compared with coated archwires for all groups (P < 0.001). Nitanium archwire showed the lowest loading and unloading forces at different deflections (P < 0.001). CONCLUSIONS: The simulated gastric acid solution decreased considerably the amount of force applied at a given deflection. The loading-deflection and surface roughness properties of coated archwires were affected by the type of coating material. CLINICAL RELEVANCE: The impact of gastric acids on surface and mechanical properties of orthodontic archwires depend on type of coating materials.
Authors: Lanna Cristina Gonçalves da Costa Vieira; Glaucia Schuindt Teixeira Neves; Georgiana Amaral; Marco André de Berredo Pinho; Ana Paula Pires Dos Santos; Cesar Dos Reis Perez Journal: Odontology Date: 2022-04-20 Impact factor: 2.885