Reliability of organic mouthwashes over inorganic mouthwashes in the assessment of corrosion resistance of NiTi arch wires

Introduction: The maintenance of oral hygiene is an integral part of orthodontic treatment. Hence, the orthodontist may prescribe mouthwashes which have positive effects on periodontal health, but to our knowledge little attention is being paid on the negative effects of these mouthwashes on the properties of arch wires. The objective of this study was to evaluate the reliability of organic mouthwashes over inorganic mouthwashes in assessment of corrosion resistance of different arch wires. Materials and Methods: The study was conducted on two different commercially available NiTi arch wires (0.016") in diameter which were divided into different groups according to the mouthwash used and the manufacturer companies. The linear polarization test performed by potentiostat was used to evaluate the corrosion resistance of commercial NiTi wires in acidic artificial saliva at 37°C. One-way analysis of variance was used to analyze polarization resistance with the wire manufacturer as the variable factor. Results: Organic mouthwashes (showed significantly decreased corrosion rate than the inorganic mouthwashes (P < 0.05). Conclusions: (1) Listerine mouthwash showed the highest corrosion rate; organic mouthwash showed the least corrosion rate whereas chlorhexidine mouthwash showed the intermediate corrosion rate. (2) High corrosion rate was observed in NiTi arch wires manufactured from Ormco and low corrosion rate was observed in NiTi arch wires manufactured from Dentaurum.