Adjunctive Effect of Photodynamic Therapy on Halitosis

The present study aims to evaluate halitosis in patients undergoing non-surgical periodontal therapy \[(Full-mouth disinfection (FMD) combined with tongue scraping and antimicrobial photodynamic therapy (aPDT), and to assess its potential benefits for both periodontal and microbiological condition. A pilot study will be performed with participants who took part almost 10 years ago in the study NCT02368678. They will be invited by phone contact. In addition, new participants will be recruited by convenience in dental clinics from the Federal University of Minas Gerais until completion of 20 participants per group. Individuals with stage III periodontitis and halitosis (organoleptic method > 2), will be allocated into two periodontal treatment groups. Halitosis will be assessed using the organoleptic method and gas chromatography (OralChroma device) at three time points: before and after treatments. Microbiological samples will be collected before and after treatments from periodontal pockets and pooled samples from the tongue dorsum. These samples will be analyzed by using real-time PCR (q-PCR) aiming at detecting target bacterial species.

• Full-mouth scaling combined with antimicrobial photodynamic therapy (Radiation): After full-mouth scaling procedures antimicrobial photodynamic therapy was carried out using a laser-activated disinfection device with a red laser emission (wavelength: 630 nm, irradiance: 2000-4000 mW/cm², spot size at the probe tip: 8 mm diameter) and high-viscosity methylene blue gel (0.1 mg/mL) which was applied at six spots on the tongue dorsum. Antimicrobial photodynamic therapy was also applied iIn sites with altered periodontal pocket depth (≥ 4mm). The dye remained in the pockets for 10 minutes to ensure full absorption and its excess was rinsed with sterile saline after laser exposure.
• full-mouth scaling (Procedure): Full-mouth scaling within 24 hours, divided into two sessions of ultrasonic instrumentation followed by manual supra- and subgingival scaling and root planing. Tongue cleaning was performed with a tongue scraper.

Primary outcomes

• sulfur volatile compounds changes [baseline versus 21 and 45 days after treatment]: pre and post-treatment changes in levels (parts per billion) of CH3SH, a sulfur volatile compound

Secondary outcomes

• Changes in periodontal probing depth [baseline versus 45 days after treatment]: Pre and pos-treatment changes in periodontal pocket depth (mm)
• Changes in organoleptic testing [Baseline versus 45 days after treatment]: Pre and post-treatment changes in organoleptic scores
• Changes in tongue total bacteria count [baseline versus 45 days after treatment]: Pre- and post-treatment changes in total bacteria counts from tongue dorsal samples

Sex: All, ages: 30 Years to 65 Years

Inclusion Criteria:

* self-reported halitosis;
* organoleptic score >2;
* stage III periodontitis;
* at least 14 teeth.

Exclusion Criteria:

* smokers or former smokers;
* individuals diagnosed with diabetes and/or immune diseases;
* pregnant or lactating women;
* individuals with removable partial dentures and/or fixed or removable orthodontic appliances;
* systemic use of antibiotics or anti-inflammatory drugs in the last three months; - individuals who required prophylactic antibiotics for periodontal exams and treatments;
* individuals who regularly used or had used any type of mouthwash in the past three months;
* individuals who underwent periodontal treatment in the six months prior to the study.

• Fernando O Costa, doctorate, Principal investigator, Federal University of Minas Gerais, Dental School