Severe acute respiratory syndrome coronavirus 2 infection prevention in orthodontic practice

We read with great interest the recent article by Guo et al (Guo Y, Jing Y, Wang Y, To A, Du S, Wang L, et al. SARS-CoV-2 infection prevention in orthodontic practice Am J Orthod Dentofac Orthop 2020;158:321-9) on severe acute respiratory syndrome coronavirus 2 infection prevention in orthodontic practice. We should not forget the limited awareness and compliance on infection prevention by standard procedures in dental and orthodontic facilities, and the lapses and errors even for dentists working from the area with the highest coronavirus disease 2019 prevalence.1, 2, 3, 4, 5 In addition to standard infection control precautions for reopening of dental services,⁶ we would like to call attention to some problems⁷ in the light to propose proper guidelines and effective protocols for orthodontic facilities.

• 1.The need to grade orthodontic instruments as critical ones.⁸
• 2.The advantages of particulate respirators (National Institute for Occupational Safety and Health-certified N95, European Union standard filtering facepiece 2 [Europe EN 149-2001] or equivalent) vs surgical mask are often over evaluated. In addition, more knowledge is needed about this topic and skin injuries by filtering facepiece.^{7 , 9}
• 3.Puncture-resistant gloves and improved glove design on the basis of test methods specific for orthodontic tasks should be evaluated in comparison with the use of double gloves.10, 11, 12, 13, 14
• 4.Alcohol-based hand sanitizers are the first choice because of the high turnover of orthodontic patients and the need for frequent hand hygiene²; awareness is requested to avoid the use of hand sanitizer products that have been tested by the U.S. Food and Drug Administration and labeled to contain ethyl alcohol, but that have tested positive for methanol contamination.¹⁵
• 5.The recommendation of an interval of 3-5 minutes between 2 consecutive patients to allow for optimal disinfection needs clarification. It could be possible with a certified medium level (activity against mycobacteria) disinfectant, low time of action (<5 minutes), wide compatibility with different clinical contact surfaces (made of metal or synthetic materials), and included in the U.S. Environmental Protection Agency's List N (https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov-2-covid-19).⁷ Unfortunately, the use of 75% alcohol and 1000 mg/L chlorine-containing disinfectant is not indicated in the Instructions for Use by the main producers of dental chair or photographic camera.
• 6.Guidelines for infection prevention using current computer-aided design, computer-aided manufacturing technology are lacking.⁴
• 7.The recommendation to discharge water for 30 seconds by handpieces and 3-way syringes needs confirmation because stagnation in dental unit waterlines (DUWL) is more frequent in orthodontic facilities. Then, it is more difficult to control water contamination and biofilm formation. We think mandatory DUWL disinfection (with products that will not interfere with bonding procedures during fixed orthodontics), water quality monitoring, and the use of drinking water in DUWL, according to guidelines and regulatory standards.16, 17, 18, 19