[1] Azim A A, Aksel H, Margaret Jefferson M, et al. Comparison of sodium hypochlorite extrusion by five irrigation systems using an artificial root socket model and a quantitative chemical method [J]. Clin Oral Investig, 2018, 22(2): 1055-1061. [2] Siqueira J F Jr, Magalhães K M, Roças I N. Bacterial reduction in infected root canals treated with 2.5% NaOCl as an irrigant and calcium hydroxide/camphorated paramonochlorophenol paste as an intracanal dressing [J]. J Endod, 2007, 33(6): 667-672. [3] Takahashi K,Machida T,Kimura Y,et al. The morphological study of root canal walls with Er: YAG laser [J]. J Jpn Endod Assoc,1996,17: 197-203. [4] Cheng X, Chen B, Qiu J, et al. Bactericidal effect of Er: YAG laser combined with sodium hypochlorite irrigation against Enterococcus faecalis deep inside dentinal tubules in experimentally infected root canals[J]. J Med Microbiol, 2016, 65(2):176-187. [5] Doganay Yildiz E, Dinçer B, Fidan M E. Effect of different laser-assisted irrigation activation techniques on apical debris extrusion [J]. Acta Odontol Scand, 2020, 78(5):332-336. [6] George R, Meyers I A, Walsh L J. Laser activation of endodontic irrigants with improved conical laser fiber tips for removing smear layer in the apical third of the root canal [J]. J Endod, 2008, 34(12):1524-1527. [7] Tunc F, Yildirim C, Alacam T. Evaluation of postoperative pain/discomfort after intracanal use of Nd:YAG and diode lasers in patients with symptomatic irreversible pulpitis and asymptomatic necrotic pulps: a randomized control trial [J]. Clin Oral Investig, 2021, 25(5):2737-2744. [8] De Moor R J, Blanken J, Meire M, et al. Laser induced explosive vapor and cavitation resulting in effective irrigation of the root canal. Part 2: evaluation of the efficacy [J]. Lasers Surg Med, 2009, 41(7): 520-523. [9] Yasuda Y, Kawamorita T, Yamaguchi H, et al. Bactericidal effect of Nd:YAG and Er:YAG lasers in experimentally infected curved root canals[J]. Photomed Laser Surg, 2010, 28(Suppl 2): S75-78. [10] Korkut E, Torlak E, Gezgin O, et al. Antibacterial and smear layer removal efficacy of Er: YAG laser irradiation by photon-induced photoacoustic streaming in primary molar root canals: a preliminary study[J]. Photomed Laser Surg, 2018, 36(9):480-486. [11] Harashima T, Takeda F H, Kimura Y, et al. Effect of Nd:YAG laser irradiation for removal of intracanal debris and smear layer in extracted human teeth[J]. J Clin Laser Med Surg, 1997, 15(3):131-135. [12] Gregorcic P, Jezersek M, Mozina J. Optodynamic energy-conversion efficiency during an Er:YAG-laser-pulse delivery into a liquid through different fiber-tip geometries[J]. J Biomed Opt, 2012, 17(7):075006. [13] Merigo E, Bufflier P, Rocca J P, et al. Bactericidal effect of Er, Cr:YSGG laser irradiation on endodontic biofilm: an ex vivo study[J]. J Photochem Photobiol B, 2021, 218: 112185. [14] Meire M A, Poelman D, De Moor R J. Optical properties of root canal irrigants in the 300-3,000-nm wavelength region [J]. Lasers Med Sci, 2014, 29(5):1557-1562. [15] DiVito E, Peters O A, Olivi G. Effectiveness of the erbium: YAG laser and new design radial and stripped tips in removing the smear layer after root canal instrumentation[J]. Lasers Med Sci, 2012, 27(2):273-280. [16] Lloyd A, Uhles J P, Clement D J, et al. Elimination of intracanal tissue and debris through a novel laser-activated system assessed using high-resolution micro-computed tomography: a pilot study [J]. J Endod, 2014, 40(4):584-587. [17] Mandras N, Pasqualini D, Roana J, et al. Influence of photon-induced photoacoustic streaming (PIPS) on root canal disinfection and post-operative pain: a randomized clinical trial[J]. J Clin Med, 2020, 9(12): 3915. [18] Passalidou S, Calberson F, De Bruyne M, et al. Debris removal from the mesial root canal system of mandibular molars with laser-activated irrigation[J]. J Endod, 2018, 44(11):1697-1701. [19] Al Shahrani M, Di Vito E, Hughes C V, et al. Enhanced removal of enterococcus faecalis biofilms in the root canal using sodium hypochlorite plus photon-induced photoacoustic streaming: an in vitro study [J]. Photomed Laser Surg, 2014, 32(5): 260-266. [20] Ozses Ozkaya B, Gulsahi K, Ungor M, et al. A comparison of Er:YAG laser with photon-initiated photoacoustic streaming, Nd:YAG laser, and conventional irrigation on the eradication of root dentinal tubule infection by enterococcus faecalis biofilms: a scanning electron microscopy study[J]. Scanning, 2017,2017: 6215482. [21] Meire M A, Havelaerts S, De Moor R J. Influence of lasing parameters on the cleaning efficacy of laser-activated irrigation with pulsed erbium lasers [J]. Lasers Med Sci, 2016, 31(4): 653-658. [22] Mathew J, Emil J, Paulaian B, et al. Viability and antibacterial efficacy of four root canal disinfection techniques evaluated using confocal laser scanning microscopy [J]. J Conserv Dent, 2014, 17(5):444-448. [23] DiVito E, Lloyd A. Er:YAG laser for 3-dimensional debridement of canal systems: use of photon-induced photoacoustic streaming[J]. Dent Today, 2012,31(11):122, 124-127. [24] Kurzmann C, Meire M A, Lettner S, et al. The efficacy of ultrasonic and PIPS (photon-induced acoustic streaming) irrigation to remove artificially placed dentine debris plugs out of an artificial and natural root model[J]. Lasers Med Sci, 2020, 35(3): 719-728. [25] Cheng X, Guan S, Lu H, et al. Evaluation of the bactericidal effect of Nd:YAG, Er:YAG, Er,Cr:YSGG laser radiation, and antimicrobial photodynamic therapy (aPDT) in experimentally infected root canals[J]. Lasers Surg Med, 2012,44(10):824-831. [26] Do Q L, Gaudin A. The Efficiency of the Er: YAG laser and photoninduced photoacoustic streaming (PIPS) as an activation method in endodontic irrigation: a literature review [J]. J Lasers Med Sci, 2020, 11(3):316-334. [27] Turkel E, Onay E O, Ungor M. Comparison of three final irrigation activation techniques: effects on canal cleanness, smear layer removal, and dentinal tubule penetration of two root canal sealers [J]. Photomed Laser Surg, 2017, 35(12):672-681. [28] Cheng X, Xiang D, He W, et al. Bactericidal effect of Er:YAG laser-activated sodium hypochlorite irrigation against biofilms of enterococcus faecalis isolate from canal of root-filled teeth with periapical lesions[J]. Photomed Laser Surg, 2017, 35(7):386-392. [29] Swimberghe R C D, Buyse R, Meire M A, et al. Efficacy of different irrigation technique in simulated curved root canals [J]. Lasers Med Sci, 2021,36(6):1317-1322. [30] Koch J D, Jaramillo D E, DiVito E, et al. Irrigant flow during photon-induced photoacoustic streaming (PIPS) using particle image velocimetry (PIV) [J]. Clin Oral Investig, 2016, 20(2): 381-386. [31] Ordinola-Zapata R, Bramante C M, Aprecio R M, et al. Biofilm removal by 6% sodium hypochlorite activated by different irrigation techniques[J]. Int Endod J, 2014, 47(7): 659-666. [32] Neelakantan P, Cheng C Q, Mohanraj R, et al. Antibiofilm activity of three irrigation protocols activated by ultrasonic, diode laser or Er:YAG laser in vitro[J]. Int Endod J, 2015, 48(6):602-610. [33] Balic M, Lucic R, Mehadzic K, et al. The efficacy of photon-initiated photoacoustic streaming and sonic-activated irrigation combined with QMiX solution or sodium hypochlorite against intracanal E. faecalis biofilm [J]. Lasers Med Sci, 2016, 31(2):335-342. [34] Cheng X, Xiang D, He W, et al. Bactericidal effect of Er:YAG laser-activated sodium hypochlorite irrigation against biofilms of enterococcus faecalis isolate from canal of root-filled teeth with periapical lesions[J]. Photomed Laser Surg, 2017, 35(7):386-392. [35] De Meyer S, Meire M A, Coenye T, et al. Effect of laser-activated irrigation on biofilms in artificial root canals [J]. Int Endod J, 2017, 50(5): 472-479. [36] Azim A A, Aksel H, Zhuang T, et al. Efficacy of 4 irrigation protocols in killing bacteria colonized in dentinal tubules examined by a novel confocal laser scanning microscope analysis[J]. J Endod, 2016, 42(6): 928-934. [37] Suman S, Verma P, Prakash-Tikku A, et al. A comparative evaluation of smear layer removal using apical negative pressure (EndoVac), sonic irrigation (EndoActivator) and Er:YAG laser -an in vitro SEM study[J]. J Clin Exp Dent, 2017, 9(8): e981-e987. [38] Arslan H, Akcay M, Capar I D, et al. An in vitro comparison of irrigation using photon-initiated photoacoustic streaming, ultrasonic, sonic and needle techniques in removing calcium hydroxide[J]. Int Endod J, 2015, 48(3):246-251. [39] Mancini M, Cerroni L, Palopoli P, et al. FESEM evaluation of smear layer removal from conservatively shaped canals: laser activated irrigation (PIPS and SWEEPS) compared to sonic and passive ultrasonic activation-an ex vivo study[J]. BMC Oral Health, 2021, 21(1): 81. [40] Kuştarci A, Er K. Efficacy of laser activated irrigation on apically extruded debris with different preparation systems [J]. Photomed Laser Surg,2015,33(7):384-389.