Table 1 . Studies Using TBO as PS .

Author/Year	Type	Bacteria	Groups	PS	Wavelength	Results
Gergova et al19 2015	In vitro	Enterococcus faecalis and other gram-positive cocci	1) Control group; 2) Laser group; 3) PDT; 4) Different chemical substances; 5) Different solution	TBO 0.1 mg/mL	660 nm P: 100 mW T: 5 min	The PDT with FotoSan, hydrogen peroxide, and all tested types of iontophoresis all showed strong disinfection potential with very small, insignificant differences.
Muhammad et al20 2014	In vitro	Enterococcus faecalis, Streptococcus salivarius, Porphyromonas gingivalis and Prevotella intermedia bacteria	1) Aseptim Plus® photo-activated (LED) disinfection system; 2) Group by a 650 nm diode laser and toluidine blue as photosensitizer; 3) Control group, by ultrasonic irrigation (PUI) using EDTA 17% and NaOCl 2.6% solutions	TBO 15 μg/mL	650 nm P: 60 mW T: 120 s	There was no statistically significant difference between results obtained from groups treated by Aseptim Plus® and diode laser.
Tennert et al212014	In vitro	Clinical isolate of E. faecalis	1) PDT group; 2) NaOCl; ) NaOCl-PDT group	TBO 13-15 mg/mL	635 nm P:100 mW T: 120 s	Antimicrobial treatment of root canals caused a significant reduction of bacterial load in all groups.
Pinheiro et al222014	In vitro	Enterococcus faecalis	1) Manual instrumentation; 2) Rotary instrumentation; (Toluidine blue O/laser, fuchsin/halogen light and fuchsin/LED)	TBO 0.005%	660 nm P: 100 mW T: 60 s	It may be concluded that both rotary and manual instrumentation reduced E. faecalis. PDT can be used as an adjuvant to conventional endodontic treatment.
Schiffner et al23 2014	In vitro	E. faecalis with mixed aerobic or anaerobic microbial populations	1) Untreated; 2) NaCl alone; 3) PAD (PS plus irradiation) for 60 s; 4) The PS alone; 5) Irradiation for 60 s alone.	TBO not mentioned	632-644 nm P: 200 mW T: 60 s	The bactericidal activity of PAD appears to be enhanced by serum proteins in vitro, but is limited to bacteria present within the root canal.
Hecker et al24 2013	In vitro	E. faecalis	1) Disinfection with NaOCl (0.5%, 1.0% or 3.0% for 30 or 60 or 600 s); 2) Disinfection with NaOCl (as above) followed by application of neutralizing solution; 3) Disinfection with the PACT 200 system.	TBO not mentioned	635 nm P: 200 mW T: 4 or 6 min	The antibacterial PDT system did not achieve sufficient disinfection.
Bago et al25 2013	In vitro	E. faecalis	1) Diode laser irradiation (2 W; 3, 9, and 20 s); 2) PAD (100 mW, 60 s); 3) PAD with 3D Endoprobe (100 mW, 60 s); 4) 30-gauge syringe irrigation with NaOCl (60 s); 5) sonic agitation of NaOCl with the EndoActivator system (60 s); 6) 30-gauge syringe irrigation with NaCl (60 s).	TBO 155 μg/ mL	660 nm P:100 mW T: 60 s	The PAD and EndoActivator system were more successful in reducing the root canal infection than the diode laser and NaOCl syringe irrigation alone.
Yao et al262012	In vitro	Enterococcus faecalis	Energy dose ranging from 0.5 to 5.5 J. 50 or 100 mW, irradiation time 5 to 55 s. part II: PAD therapy; 5.25% NaOCl irrigation and saline	TBO 12.7 μg/mL	635 nm P: 100 mW E: 0.5 to 5.5J	PAD could decrease E. faecalis in root canals effectively, but was no more effective than 5.25% NaOCl.
Vaziri et al27 2012	In vitro	E. faecalis	1) Sodium hypochlorite (NaOCl) irrigation; 2) Diode laser plus 2.5% NaOCl; 3) PDT; 4) 2.5% NaOCl plus PDT; 5) Chlorhexidine irrigation; 6) Control groups	TBO 15 μg/mL	625 nm 200 mw/cm2 60 s	Combination of PDT and 2.5% NaOCl achieved maximum reduction in recovered viable bacteria, no viable bacteria was observed after treatment of PDT + 2.5% NaOCl.
Meire et al282012	In vitro	E. faecalis	1) aPDT (Denfotex Helbo system); 2) Er:YAG laser irradiation (2940 nm, 50 mJ or 100 mJ, 15 Hz, 40 s); 3) Er:YAG laser irradiation (2940 nm, 100 mJ, 15 Hz, 40 s); 4) Nd:YAG laser irradiation (1064 nm, 2 W, 15 Hz, 40 s); 5) immersion in 2.5% (w/v) NaOCl for 1 min; 6) immersion in 2.5% (w/v) NaOCl for 5 min; 7) immersion in 2.5% (w/v) NaOCl for 10 min; immersion in 2.5% (w/v) NaOCl for 30 min in control group; 8) NaOCl 0.25% + Er:YAG	TBO 12.7 mg /mL	635 nm P: 100 mw T: 10 s	The use of both commercial aPDT systems resulted in a weak reduction in the number of E. faecalis cells.
Poggio et al29 2011	In vitro	Enterococcus faecalis, Streptococcus mutans and Streptococcus sanguis strains	1) Teeth treated with PAD (FotoSan system); 2) teeth treated with PAD and with 5% NaOCl solution; 3) teeth irrigated with TBO; 4) teeth treated with PAD for longer time (FotoSan system);5) teeth irrigated with 5% NaOCl solution (positive control).	TBO 100 μg/mL	628 nm P:1 w T: 30 or 90 s	PAD applied for a longer time (in respect to manufacturer’s instructions) or PAD associated to 5% NaOCl showed the significantly higher antibacterial effects.
Rios et al30 2011	In vitro	E. faecalis	Five‏ experimental groups and three control groups: 1) NaOCl; 2) toluidine blue O (TBO); (3) light: canals were filled with sterile saline; (4) TBO/light; (5) NaOCl/TBO/light	TBO low viscosity	635 nm 30 s	PDT using TBO and a LED lamp has the potential to be used as an adjunctive antimicrobial procedure in conventional endodontic therapy.
Schlafer et al312010	In vitro	Escherichia coli, Candida albicans, Enterococcus faecalis, Fusobacterium nucleatum, and Streptococcus intermedius	1) T−L−, No TBO, no light (negative control treatment); 2) T+L−, TBO, no light; 3) T−L+, no TBO irradiation; 4) T+L+, TBO + irradiation	TBO 100 µg/mL	628 nm 30 s	PAD yielded significant reductions in the viable counts of all organisms in planktonic suspension.
Souza et al32 2010	In vitro	E. faecalis	1) MB/NaOCl (PDT with MB and NaOCl as the irrigant), 2) TB/NaOCl (PDT with TBO and NaOCl as the irrigant), 3) MB/NaCl (PDT with MB and NaCl as the irrigant), 4) TB/NaCl (PDT with TBO and NaCl as the irrigant)	MB 15 µg/mL	660 nm 40 mW T: 4 min	These in vitro results suggest that PDT with either MB or TBO may not exert a significant supplemental effect to instrumentation/irrigation procedures.
Meire et al33 2009	In vitro	E. faecalis	1) Nd:YAG laser 2) KTP laser 3) PAD treatment 4) NaOCl solution 5) positive control	TBO 12.7 mg /mL	635 nm P:100 mW T: 150 s Energy: 15 J	In aqueous suspension, PAD and NaOCl resulted in a significant reduction in the number of E. faecalis.
Bergmans et al342008	In vitro	Streptococcus anginosus, E. faecalis or Fusobacterium nucleatum	1) PAD 2) Laser 3) Dye 4) Positive control	TBO 12.7 mg/mL	635 nm P:100 mW T: 150 s	Treatment of root canals with PAD (15 J) caused a significant reduction of the bacterial load, resulting in a 93.8% kill of S. anginosus (P<0.0001), a 88.4% kill of E. faecalis.
Fonseca et al352008	In vitro	E. faecalis	1) Control group and 2) test group	TBO 0.0125%	660 nm P: 50 mW	The mean decrease in CFU/mL was 99.9% in the test group.
Bonsor et al36 2006	In vivo	Fusobacterium nucleatum, Prevotella intermedia, Streptococcus intermedius and Peptostreptococcus micros	A microbiological sample of the canal was taken on accessing the canal, after conventional endodontic therapy, and finally	TBO	635 nm 60 s at 100 mW	The PAD system offers a means of destroying bacteria remaining after using conventional irrigants in endodontic therapy.