Photobiomodulation for Pain Relief After Third Molar Extraction: A Randomized Double-Blind Split-Mouth Clinical Trial.

Objective: To evaluate the local and systemic application of photobiomodulation (PBM) to reduce pain after third molar extraction. Background: PBM has been applied locally to reduce pain after third molar extraction, but there are no published studies evaluating its systemic application for this purpose. Methods: Thirty patients with two erupted third molars indicated for extraction were included in this split-mouth clinical trial. Extractions were performed 3 weeks apart in each patient, with one extraction socket being randomly assigned to local and systemic PBM (PBM group) and the other to no PBM (control group). Postoperative analgesia consisted of oral acetaminophen for 3 days. Outcomes included pain (visual analog scale), swelling, and quality of life (14-item Oral Health Impact Profile) assessed before and immediately, 24 h, 48 h, and 7 days after extraction. Results were analyzed by Kruskal-Wallis test, followed by Student-Newman-Keuls test. Results: In the control group, pain increased significantly at 24 and 48 h after extraction (p = 0.0000), decreasing after 7 days (before: 0.36; immediately after: 1.06; 24 h: 4.26; 48 h: 2.53; 7 days: 0.36). In the PBM group, patients reported no pain at all time points, indicating effectiveness of local and systemic PBM in relieving pain after third molar extraction (p = 0.2151) (before: 0.30; immediately after: 0.36; 24 h: 0.86; 48 h: 0.30; 7 days: 0.03). PBM also had a modulatory effect on the inflammatory process and improved comfort after extraction. Conclusions: Combined local and systemic PBM can be useful for pain relief, swelling control, and quality-of-life improvement in patients undergoing third molar extraction.

In vitro evaluation of EDTA combined with photodynamic therapy to reduce Streptococcus mutans in carious dentin.

BACKGROUND: This in vitro study aimed to evaluate the use of EDTA combined with photodynamic therapy to reduce Streptococcus mutans in carious dentin. METHODS: Sixty third molars were sectioned to obtain flat dentin surfaces. All specimens were waterproofed, except for the coronal dentin, and subjected to cariogenic challenge in brain-heart infusion (BHI) broth supplemented with 0.5% yeast extract, 1% glucose, 1% sucrose, and standard strain of S. mutans (ATCC 25175). The specimens were divided into 6 groups (n = 10 each): (1) control - caries collection; (2) EDTA - 17% EDTA was actively applied with a microbrush for 1 min; (3) aPDT - antimicrobial photodynamic therapy with 0.01% methylene blue photosensitizer (wavelength of 660 nm, energy of 4 J, power of 100 mW, spot size of 0.028 cm2, energy density of 142 J/cm2 for 40 s); (4) EDTA+aPDT - 17% EDTA actively applied for 1 min plus aPDT; (5) (EDTA+PT) + L - application of EDTA compounded with photosensitizer plus laser irradiation; and (6) PT - photosensitizer alone. Collection of caries was performed after the different cavity disinfection protocols. Aliquots from each dilution were seeded for colony-forming unit (CFU) counts. The results were log10-transformed and analyzed by the Kruskal-Wallis test (Student-Newman-Keuls). RESULTS: There was a significant reduction in S. mutans after aPDT (p<0.05), EDTA+aPDT (p<0.001), and (EDTA+PT) + L (p<0.001). The percentage of microbial reduction in ascending order was as follows: EDTA: 1.65%; PT: 15.51%; aPDT: 38.28%; EDTA+aPDT: 75.24%; and (EDTA+PT) + L: 97.35%. CONCLUSION: Application of 17% EDTA prior to photosensitization or compounded with a photosensitizer increased the antimicrobial effect of aPDT on S. mutans in carious dentin.