“…Loncar, et al, (2009) point out that the duration of the application varies from 10 to 80 seconds, however, according to Oliveira, Mendes (2009), it is 2 to 3 minutes. Makeeva, et al, (2017) observed that in less invasive procedures, such as in white spot lesions, for example, the gas mixture was used for 24 seconds under the element in question, while in EAR lesions, Al-Omiri, et al, (2016) irrigating agent throughout the procedure and, Oliveira, et al, (2018) add that, in the context of GUN, the ozonized oil was applied without a specific time interval. Regarding the concentration, it is known that the maximum allowed for the clinical application of the ozone-oxygen gas mixture is 5% or 100 µg / ml of ozone, where 1 µg / ml means that it contains 0.05% O3, and 100 µg / ml contains 5% (FERREIRA, 2011; NOGALES, 2011).…”