Participants in this group will perform brushing, dental floss and tongue scraper.

Participants in this group will receive brushing, dental floss, tongue scraper and aPDT with blue LED and annatto.

Participants in this group will receive brushing, dental floss, lingual scraper and aPDT with blue LED, annatto and probiotic lozenges containing Streptococcus salivarius K12 (BLIS K12®).

Participants in this group will receive brushing, dental floss, lingual scraper and probiotic lozenges containing Streptococcus salivarius K12 (BLIS K12®).

Participant will be taught on how to correctly brush their teeth, use dental floss and scrape their tongues at home.

The collection of oral air will follow the manufacturer's instructions (Oral ChromaTM Manual Instruction), where the participant will be instructed to rinse with cysteine (10 mM) for 1 minute, then keep their mouth closed for another minute. A syringe from the same manufacturer, suitable for collecting oral air, will be placed in the patient's mouth. For 1 minute, the patient will remain with their mouth closed, breathing through their nose, without touching the syringe with their tongue. The plunger will be pulled out, we will empty the air from the syringe into the patient's mouth again and pull the plunger again to fill the syringe with the breath sample. We will clean the tip of the syringe with gauze to remove moisture from the saliva, place the gas injection needle on the syringe, and adjust the plunger to 0.5 ml. The collected gases are injected into the inlet port of the device with a single movement.

The samples will be collected with a swab on the back of the tongue, then placed in an eppendorf containing BHI (Brain Heart Infusion) serving as a transport medium, for later cultivation of these samples to be able to detect the total number of viable bacteria. Initially, the samples will be homogenized for 30 seconds in a Vortex apparatus, and then diluted in the order of 10-1 to 10-5 in a 96-well microtiter plate containing 180 microliters of PBS in each well. We take 20 microliters of each sample and follow the dilution sequence. After the dilution is performed, we will take 5 aliquots of 10 microliters of this suspension and they will be seeded in a petri dish with blood agar. The cultures will then be incubated for 72 hours at 37°C in an atmosphere of 85% nitrogen (N2), 10% carbon dioxide (CO2) and 5% hydrogen (H2), achieved through the use of an anaerobic generation system. This will provide visual access to the total number of viable bacteria in colony forming units (CFU).