Dispersion of near-infrared laser energy through radicular dentine when using plain or conical tips

Lasers in Medical Science - Tập 33 - Trang 251-255 - 2017
Christine Yi Jia Teo1, Roy George2, Laurence J. Walsh1
1The University of Queensland, School of Dentistry, Herston, Australia
2School of Dentistry and Oral Health, Gold Coast campus, Griffith University, Nathan, Australia

Tóm tắt

The aim of this study was to investigate the influence of tip design on patterns of laser energy dispersion through the dentine of tooth roots when using near-infrared diode lasers. Diode laser emissions of 810 or 940 nm were used in combination with optical fiber tips with either conventional plain ends or conical ends, to irradiate tooth roots of oval or round cross-sectional shapes. The lasers were operated in continuous wave mode at 0.5 W for 5 s with the distal end of the fiber tip placed in the apical or coronal third of the root canal at preset positions. Laser light exiting through the roots and apical foramen was imaged, and the extent of lateral spread calculated. There was a significant difference in infrared light exiting the root canal apex between plain and conical fiber tips for both laser wavelengths, with more forward transmission of laser energy through the apex for plain tips. For both laser wavelengths, there were no significant differences in emission patterns when the variable of canal shape was used and all other variables were kept the same (plain vs conical tip, tip position). To ensure optimal treatment effect and to prevent the risks of inadvertent laser effects on the adjacent periapical tissues, it is important to have a good understanding of laser transmission characteristics of the root canal and root dentine. Importantly, it is also essential to understand transmission characteristics of plain and conical fibers tips.

Tài liệu tham khảo

Klinke T, Klimm W, Gutknecht N (1997) Antibacterial effects of Nd:YAG laser irradiation within root canal dentin. J Clin Laser Med Surg 15(1):29–31 Lagemann M, George R, Chai L, Walsh LJ (2014) Activation of ethylenediaminetetraacetic acid EDTA by a 940 nm diode laser for enhanced removal of smear layer. Aust Endod J 40(2):72–75 Wilson M (1993) Photolysis of oral bacteria and its potential use in the treatment of caries and periodontal disease. J Appl Bacteriol 75(4):299–306 Bondi C, Cavalli A, Cetrullo N, D'Aversa L, Vallania G (1994) The CO2 laser and endodontic surgery: an epicritical evaluation. Minerva Stomatol 43(3):71–78 George R, Meyers IA, Walsh LJ (2008) Laser activation of endodontic irrigants with improved conical laser fiber tips for removing smear layer in the apical third of the root canal. J Endod 34(12):1524–1527 George R, Chan K, Walsh LJ (2015) Laser-induced agitation and cavitation from proprietary honeycomb tips for endodontic applications. Lasers Med Sci 30(4):1203–1208 Waplington M, McRobert AS (2014) Shaping the root canal system. Br Dent J 216(6):293–297 Zehnder M (2006) Root canal irrigants. J Endod 32(5):389–398 Kimura Y, Wilder-Smith P, Matsumoto K (2000) Lasers in endodontics: a review. Int Endod J 33(3):173–185 Moritz A, Gutknecht N, Doertbudak O, Goharkhay K, Schoop U, Schauer P, Sperr W (1997) Bacterial reduction in periodontal pockets through irradiation with a diode laser: a pilot study. J Clin Laser Med Surg 15(1):33–37 Moritz A, Gutknecht N, Goharkhay K, Schoop U, Wernisch J, Sperr W (1997) In vitro irradiation of infected root canals with a diode laser: results of microbiologic, infrared spectrometric, and stain penetration examinations. Quintessence Int 28(3):205–209 Moritz A, Schoop U, Goharkhay K, Schauer P, Doertbudak O, Wernisch J, Sperr W (1998) Treatment of periodontal pockets with a diode laser. Lasers Surg Med 22(5):302–311 George R, Walsh LJ (2012) Laser fiber optic modifications and their role in endodontics. Journal of Laser Dentistry 20(1):24–30 Saydjari Y, Kuypers T, Gutknecht N (2016) Laser application in dentistry: irradiation effects of Nd:YAG 1064 nm and diode 810 nm and 980 nm in infected root canals—a literature overview. Biomed Res Int 2016:8421656 Chen EW, Carey AJ, Ulett GC, George R (2015) Characterisation of the efficacy of endodontic medications using a three-dimensional fluorescent tooth model: an ex vivo study. Aust Endod J 41(2):88–96 Chen BK, George R, Walsh LJ (2014) Discoloration of roots caused by residual endodontic intracanal medicaments. ScientificWorldJournal 2014:404676 Chen BK, George R, Walsh LJ (2012) Root discolouration following short-term application of steroid medicaments containing clindamycin, doxycycline or demeclocycline. Aust Endod J 38(3):124–128 Perin FM, Franca SC, Silva-Sousa YT, Alfredo E, Saquy PC, Estrela C, Sousa-Neto MD (2004) Evaluation of the antimicrobial effect of Er:YAG laser irradiation versus 1% sodium hypochlorite irrigation for root canal disinfection. Aust Endod J 30(1):20–22 Jha D, Guerrero A, Ngo T, Helfer A, Hasselgren G (2006) Inability of laser and rotary instrumentation to eliminate root canal infection. J Am Dent Assoc 137(1):67–70 George R, Walsh LJ (2011) Performance assessment of novel side firing safe tips for endodontic applications. J Biomed Opt 16(4):048004 George R, Walsh LJ (2009) Performance assessment of novel side firing flexible optical fibers for dental applications. Lasers Surg Med 41(3):214–221 Ho QV, George R, Sainsbury AL, Kahler WA, Walsh LJ (2010) Laser fluorescence assessment of the root canal using plain and conical optical fibers. J Endod 36(1):119–122 George R, Walsh LJ (2010) Thermal effects from modified endodontic laser tips used in the apical third of root canals with erbium-doped yttrium aluminium garnet and erbium, chromium-doped yttrium scandium gallium garnet lasers. Photomed Laser Surg 28(2):161–165 Hmud R, Kahler WA, Walsh LJ (2010) Temperature changes accompanying near infrared diode laser endodontic treatment of wet canals. J Endod 36(5):908–911 Masayuki O, Mineo K, Junji T (2010) Transmission of diode laser through dentin. JJpnSocLaser Dent 21:18–21 Falkenstein F, Gutknecht N, Franzen R (2014) Analysis of laser transmission and thermal effects on the inner root surface during periodontal treatment with a 940-nm diode laser in an in vitro pocket model. J Biomed Opt 19(12):128002 George R, Rutley EB, Walsh LJ (2008) Evaluation of smear layer: a comparison of automated image analysis versus expert observers. J Endod 34(8):999–1002