Table 2.

Antimicrobial photodynamic therapy studies.

Authors	Study	Conclusion
Wilson et al [25]	Investigated the bactericidal effect of 27 PSs at concentration 0.005% (wt/vol) for their ability to sensitize Streptococcus sanguinis with 7.3 mW helium/neon (HeNe) laser, during 30 s	Most effective were TBO, MB, aluminum disulphonated phthalocyanine (AlPcS₂), crystal violet and dihematoporphyrin esther (DHE). In the absence of light, PSs were not effective
Burns et al [26]	Application of PDT against bacteria causing tooth decay (S. mutans, S. sobrinus, L. casei and A. viscosus) with PS aluminium disulphonated phthalocyanine, combined with gallium aluminium arsenide laser with exposure times (30–60 s)	Bacteria were sensitive to laser light combined with a PS, providing a reduction of 10⁸–10⁶ CFU
Burns et al [40]	Evaluated PDT mediated by toluidine blue or aluminium disulphonated phthalocyanine combined with helium–neon (876, 1.752 and 3.504 mJ) or gallium–aluminium–arsenide laser (1.188, 2.376 and 4.752 mJ), respectively, in cariogenic bacteria S. mutans	Significant reductions of these cariogenic bacteria S. mutans (10⁷ CFU) when used with 438 and 1.314 mJ of helium–neon laser light and 594 and 1.782 mJ of light from the gallium–aluminium–arsenide laser. Prolonged exposure led to kill of higher concentrations (10⁸–10¹⁰ CFU)
Pfitzner et al [9]	PDT with chlorine e6, BLC 1010 and BLC 1014 at a concentration of 10 μg was used in periodontal bacteria (P. gingivalis, F. nucleatum, and C. gingivalis) associated with laser (5.3 J cm⁻²)	The microorganisms were photoinactivated completely with chlorine e6 and BLC 1010 dyes, which were able to induce the inhibition zones of the agar plates
Sigusch et al [51]	Investigated PDT efficacy in two periodontal bacterial species (P. gingivalis and F. nucleatum) using PSs chlorine e6 and BLC 1010 associated with 662 nm and 0.5 W diode laser	PDT showed a significant reduction in clinical signs of inflammation and redness in comparison to the control group
Meisel and Kocher [52]	This literature review describes the use of PDT under a periodontal perspective	PDT may be an important adjunct therapy to conventional techniques for bacterial control of periodontal diseases
Jori et al [10]	Use of PSs positively charged at physiological pH values and characterized by a moderate hydrophobicity to kill microorganisms at 5–10 min and ~50 mW cm⁻²	PDT is an efficacious alternative modality for the treatment of localized microbial infections including a variety of oral infections
Oliveira et al [53]	Ten patients with aggressive periodontitis were treated with PDT (690 nm; 60 mW cm⁻²; 10 s) associated with a phenothiazinium PS (10 mg ml⁻¹; 1 min) or scaling and root planing (SRP) with hand instruments	PDT and SRP showed similar clinical outcomes in the non-surgical treatment of aggressive periodontitis. However, PDT presents advantages, such as reducing the treatment time
Qin et al [50]	Investigated the parameters for efficient aPDT in supragingival biofilms from 20 volunteers with periodontal disease, using toluidine blue dye and diode laser (635 nm)	The therapeutic effect was improved with the following combination: 1 mg ml⁻¹ of the dye with laser irradiation of 12 J cm⁻² with survival of bacteria around 4%
Fontana et al [54]	Investigated the effects of the PDT using MB (25 μg ml⁻¹ to planktonic cells and 25 and 50 μg ml⁻¹ for biofilms) on human dental plaque microorganisms using red light at 665 nm, 100 mW cm⁻² and 30 J cm⁻²	Oral bacteria in biofilms were less affected by PDT (32% killing) than bacteria in planktonic phase (63% killing)
Dovigo et al [21]	Evaluated PDT mediated by curcumin against C. albicans, C. tropicalis and C. glabrata. Candida suspensions were treated with curcumin (5, 10 and 20 μM for planktonic forms and 20, 30 and 40 μM for biofilms) using four LEDs (5.28, 18, 25.5 and 37.5 J cm⁻², at 595 nm)	The combination of curcumin and light promoted a significant antifungal effect against yeast planktonic forms. The use of 40 mM curcumin reduced the metabolic activity of C. albicans, C. glabrata, C. tropicalis by 85, 85 and 73%, respectively, at 18 J cm⁻²
Schneider et al [49]	Evaluated the impact of PDT on the viability of S. mutans cells using an artificial model of biofilm and phenothiazinium chloride 1% combined with laser at 660 nm and 100 mW	Laser irradiation was an essential part of aPDT able to reduce the bacteria inside of a 10 μm layer
Araujo et al [44]	Susceptibility of S. mutans and Lactobacillus acidophilus to PDT grown as multi-species in the biofilm phase versus in dentine carious lesions was evaluated using curcumin at 0.75, 1.5, 3.0, 4.0 and 5.0 g L⁻¹) combined with blue LED under 5.7 J cm⁻²	A significant reduction (p < 0.05) in cell viability of the biofilm phase following photosensitization using all curcumin concentrations was observed. To achieve significant bacterial reduction (p < 0.05) in carious dentine, it was necessary to use 5.0 g L⁻¹ of curcumin in association with blue light
Shrestha et al [46]	Evaluated the effect of antibiofilm polymeric chitosan nanoparticles with rose bengal against E. faecalis biofilm	The nanoparticles demonstrated high antibacterial activity by adhesion and lysis of the bacterial cells after photodynamic treatment, reducing the viability of E. faecalis biofilms and leading to disruption of the biofilm structure
Bulit et al [47]	Evaluated the effect of PSs (curcumin, eosin Y, and/or rose bengal) on the viability of lactobacilli, the odontoblast like cells, undifferentiated cells of the pulp, and human embryonic stem cells, incubated for 15 min and then irradiated with blue light (240 s)	A significant reduction of viability was found after exposure to different combinations of PSs and light for disinfection
Oliveira et al [48]	Antimicrobial effect of PDT using methylene blue (50 μM) and low level laser (660 nm, 100 mW and 9 J) was evaluated against C. albicans, Pseudomonas aeruginosa, E. faecalis and Staphylococcus aureus	Gram-positive bacteria E. faecalis and S. aureus were eliminated more than 90%, showing that despite PDT not reducing the microorganisms completely, the results obtained lead to the conclusion that the treatment was able to promote the reduction of microbial cell viability using the selected parameters
Voos et al [45]	Antibacterial efficacy of PDT was compared using safranine O and chlorhexidine (CHX 0.2%) in an ex vivo on planktonic cultures of Streptococcus gordonii, S. mutans, F. nucleatum, P. gingivalis and Aggregatibacter actinomycetemcomitans	PDT promoted bacterial reduction >5 − log₁₀ for both PSs tested in comparison with chlorhexidine (p < 0.05)
Melo et al [55]	Investigated the effectiveness of photochemistry as antimicrobial alternative to treat deep caries, using a LED (94 J cm⁻²; ~630 nm; 150 mW) combined with TBO (100 g ml⁻¹).	Significant reductions on S. mutans, Lactobacillus spp. were demonstrated and this therapy was found to be a promising potential for the treatment of deep caries lesions
Nielsen et al [56]	Evaluated the effect of photoactivated disinfection (PAD) using riboflavin (266 μmol l⁻¹) and blue LED light (630 nm) for activation (0.4 W; 37.7 J cm⁻²; 0.63 W cm⁻²; 1 min), comparing it to PAD using TBO and red light, for endodontic and periodontal treatment	Limited microbial kills using riboflavin/blue light were found for endodontic and periodontal treatment, which suggests that riboflavin cannot be recommended as PS for PAD
Junqueira et al [57]	Utilization of functional polymeric systems composed of poloxamer 407, Carbopol 934P and MB showing a capability for singlet oxygen generation for PDT	They demonstrated the formulation of a system with a gelation temperature and MB release, intended to be applied on the skin and/or mucous membranes
Hamblin et al [59]	Describes the perspective of the use of PDT according to the research group of Dr Michael R Hamblin, in the Wellman Center for Photomedicine at Massachusetts General Hospital and Harvard Medical School	Regarding application in the field of dentistry, it is expected that nanomaterials will play a great role in restorative dentistry. They demonstrated special interest in the use of self-assembled nano-drug carriers (micelles, liposomes, etc) for PDT approach
Souza et al [60]	This review reveals that heterogeneous protocols of aPDT have been used as a strategy for adjunct treatment of aggressive periodontitis	An approach that used 0.25 W cm⁻² for 10 s per site in four sessions of aPDT divided over 15 days was found to be the better protocol for this purpose
Meerovich et al [65]	Investigated the inactivation capacity in planktonic and biofilm cultures of Gram-negative P. aeruginosa using synthetic bacteriochlorins with four and eight cationic groups	The inactivation was efficient against Gram-negative bacteria in the planktonic and biofilm phases with 0.005 mM and 8 J cm⁻², decreasing by 4 (bacteriochlorin-4) and 5 (bacteriochlorin-8) logs for planktonic form. The bacteriochlorin-8 was more efficient than bacteriochlorin-4