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Bactericidal effect of Er,Cr:YSGG laser irradiation on endodontic biofilm: An ex vivo study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 218:112185. [PMID: 33819769 DOI: 10.1016/j.jphotobiol.2021.112185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/05/2021] [Accepted: 03/29/2021] [Indexed: 11/22/2022]
Abstract
AIM This ex vivo study aimed to evaluate the of Er,Cr:YSGG laser effectiveness in the decontamination of an endodontic biofilm. MATERIALS AND METHODS Seventy-three single rooted human teeth, freshly were chosen. Each tooth was exposed to four associated species in an endodontic biofilm (Enterococcus faecalis, Streptococcus salivarius, Porphyromonas gingivalis, and Prevotella intermedia) and randomly allocated to one of the seven experimental groups. The group 1 (7 teeth) was used to finalize the reliable biofilm-forming technique. The groups 2 and 3 (15 teeth each group) were irradiated with two different Er;Cr:YSGG laser settings (0,75 W - 40 Hz and 4 W - 40 Hz, respectively). The groups 4 and 5 (15 teeth each group) were irrigated with two different solutions and laser irradiated with the same settings (1,5 W - 15 Hz). The group 6 (6 teeth) was the control group treated only with 4 ml 2,5% NaOCl irrigation during 60 s. RESULTS The observations of group 2 and 3 specimens showed the ripeness of the biofilm with the presence of Enterococcus faecalis and Streptococcus salivarius in chains but in group 3 thermal edge effects produced by the optic fiber in the canal walls were present. The group 4 specimens observation showed an average cleaning of the root canal walls while on the canal walls of group 5 samples the apical third presented several debris and smear layer and in the centre cracks and melting dentin of the radicular wall were observed. CONCLUSION In those experimental conditions, this study, demonstrated that Er,Cr:YSGG laser has a canals decontamination ability when associated to NaOCl irrigation.
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Bermúdez-Jiménez C, Niño-Martínez N, Patiño-Marín N, Martínez-Gutiérrez F, Ruiz F, Bach H, Martínez-Castañón G. Effective control of biofilms by photothermal therapy using a gold nanorod hydrogel. J Biomed Mater Res B Appl Biomater 2019; 108:333-342. [PMID: 31041849 DOI: 10.1002/jbm.b.34392] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 02/25/2019] [Accepted: 04/04/2019] [Indexed: 11/09/2022]
Abstract
Biofilms are matrices synthesized by bacteria containing polysaccharides, DNA, and proteins. The development of biofilms in infectious processes can induce a chronic inflammatory response that may progress to the destruction of tissues. The treatment of biofilms is difficult because they serve as a bacterial mechanism of defense and high doses of antibiotics are necessary to treat these infections with limited positive results. It has been demonstrated that photothermal therapy using gold nanorods (AuNRs) is an attractive treatment because of its anti-biofilm activity. The purpose of this work was to generate a novel chitosan-based hydrogel embedded with AuNRs to evaluate its anti-biofilm activity. AuNRs were synthesized by the seed-mediated growth method and mixed with the chitosan-based hydrogel. Hydrogels were characterized and tested against two bacterial strains by irradiating the produced biofilm in the presence of the nanoformulation with a laser adjusted at the near infrared spectrum. In addition, the safety of the nanoformulation was assessed with normal human gingival fibroblasts. Results showed that a significant bacterial killing was measured when biofilms were exposed to an increase of 10°C for a short time of 2 min. Moreover, no cytotoxicity was measured when normal gingival fibroblasts were exposed to the nanoformulation using the bactericidal conditions. The development of the reported formulation can be used as a direct application to treat periodontal diseases or biofilm-produced bacteria that colonize the oral cavity.
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Affiliation(s)
- Carlos Bermúdez-Jiménez
- Laboratorio de Nanobiomateriales, Facultad de Estomatología, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Nereyda Niño-Martínez
- Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Nuria Patiño-Marín
- Laboratorio de Nanobiomateriales, Facultad de Estomatología, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | | | - Facundo Ruiz
- Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Horacio Bach
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gabriel Martínez-Castañón
- Laboratorio de Nanobiomateriales, Facultad de Estomatología, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
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Liu J, Andrukhov O, Laky M, Nürnberger S, Moritz A, Lyu P, Rausch-Fan X. Behavior of human periodontal ligament cells on dentin surfaces ablated with an ultra-short pulsed laser. Sci Rep 2017; 7:12738. [PMID: 28986527 PMCID: PMC5630637 DOI: 10.1038/s41598-017-12871-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 09/15/2017] [Indexed: 12/20/2022] Open
Abstract
This study aimed to evaluate the effects of an ultrashort pulsed laser (USPL) (1064 nm, 20 ps, 100 kHz) with different laser fluences (F, 4, 6, 8 J/cm2) and pulse overlaps (PO, 0, 50%) on human periodontal ligament cells (hPDLs) behavior. Dentin samples were ablated with USPL with different combinations of fluences and pulse overlaps; some samples were ablated with an Er:YAG laser (2940 nm, 150 µs, 100 mJ/pulse, 5 J/cm2) and some samples were ground with a carbide bur. Then hPDLs were grown on the samples after different treatments. Dentin morphology and cell adhesion were observed with SEM and gene expressions were measured by RT-PCR. The results showed dentin surfaces ablated with USPL when F = 4 J/cm2, PO = 0, and F = 6 J/cm2, PO = 0 were partially intact with obvious ridges and valleys and cells on these surfaces grew mostly along the valleys. USPL ablated surfaces in other groups were entirely ablated and cell cluster formation was observed. The RT-PCR results showed an upregulation of osteocalcin of cells grown on the dentin after some laser treatment. It can be concluded that USPL could improve the attachment and differentiation of hPDLs and thus potentially promote periodontal tissue regeneration.
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Affiliation(s)
- Jing Liu
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, 100081, China.,Division of Conservative Dentistry and Periodontology, School of Dentistry, Medical University of Vienna, Vienna, Austria.,Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, 100081, China.,National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, 100081, China.,Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, 100081, China
| | - Oleh Andrukhov
- Division of Conservative Dentistry and Periodontology, School of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Markus Laky
- Division of Conservative Dentistry and Periodontology, School of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Sylvia Nürnberger
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Austrian Cluster for Tissue Regeneration, AUVA Research Center, Vienna, Austria
| | - Andreas Moritz
- Division of Conservative Dentistry and Periodontology, School of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Peijun Lyu
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing, 100081, China. .,Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, 100081, China. .,National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, 100081, China. .,Research Center of Engineering and Technology for Digital Dentistry, Ministry of Health, Beijing, 100081, China.
| | - Xiaohui Rausch-Fan
- Division of Conservative Dentistry and Periodontology, School of Dentistry, Medical University of Vienna, Vienna, Austria.
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Mohammadi Z, Jafarzadeh H, Shalavi S, Sahebalam R, Kinoshita JI. Laser-based Disinfection of the Root Canal System: An Update. J Contemp Dent Pract 2017; 18:74-77. [PMID: 28050991 DOI: 10.5005/jp-journals-10024-1993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Microorganisms have been considered to have played a critical role in the initiation and development of pulpo-periapical diseases. Some evidences have shown that mechanical instrumentation may leave considerable portions of canal surfaces undebrided. Therefore, some supplemental methods, such as the use of chemical solutions and/or lasers, have been introduced to further disinfect the complicated canal anatomy and destroy as many microorganisms as possible. The purpose of this review was to address a brief review of characteristics of lasers and their effects to disinfect the root canal in endodontics.
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Affiliation(s)
- Zahed Mohammadi
- Iranian Center for Endodontic Research, Research Institute of Dental Sciences, Shaheed Beheshti University of Medical Sciences, Tehran, Islamic Republic of Iran; Iranian National Elite Foundation, Tehran, Islamic Republic of Iran
| | - Hamid Jafarzadeh
- Department of Endodontics, Faculty of Dentistry, Dental Research Center, Mashhad University of Medical Sciences Mashhad, Islamic Republic of Iran, Phone: +985138829501, e-mail: ,
| | - Sousan Shalavi
- General Dental Practitioner, Hamedan, Islamic Republic of Iran
| | - Rasoul Sahebalam
- Department of Pediatric Dentistry, Faculty of Dentistry, Mashhad University of Medical Sciences, Mashhad, Islamic Republic of Iran
| | - Jun-Ichiro Kinoshita
- Department of Conservative Dentistry, Showa University Dental Hospital, Tokyo, Japan
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Mitić A, Popović J, Živković S, Mitić V, Nikolić M, Dačić S. EFFECTS OF LASER TREATMENT ON INTRACANAL DENTINE AND CEMENTUM AT THE ROOT APEX. ACTA MEDICA MEDIANAE 2016. [DOI: 10.5633/amm.2016.0104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Muhammad OH, Rocca JP, Fornaini C, Medioni E. Evolution of the role of phototherapy during endodontic decontamination. Laser Ther 2015; 24:291-302. [PMID: 26877593 DOI: 10.5978/islsm.15-or-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A microbe free root canal space before obturation leads to higher success rate and conventional chemo-mechanical debridement might not achieve this goal completely. First trials of laser in dentistry started from surgical intervention on caries and bones of oral cavity and extended to prepare cavities and even shaping root canals. Afterward lasers were implicated soon into direct debridement of root canal space. Anyhow failure of laser to remove debris totally from root canal space is demonstrated recently, additionally it might lead to damages to surrounding tissues or inorganic material of root canal if be used without precaution. Nowadays the theory of light assisted protocols became another start point for laser in endodontics. Laser has been introduced as an adjuvant to conventional debridement of root canals. We used Medline search engine to collect scientific publications to edit this review article in purpose of revealing the evolution of laser position from an ultimate cleaning methodology to an adjuvant to conventional root canal disinfection protocols.
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Affiliation(s)
- Omid Heidar Muhammad
- MICORALIS Laboratory (EA 7354), Faculté d'Odontologie, Université de Nice-Sophia Antipolis
| | - Jean-Paul Rocca
- MICORALIS Laboratory (EA 7354), Faculté d'Odontologie, Université de Nice-Sophia Antipolis; Pôle Odontologie, CHU NICE
| | | | - Etienne Medioni
- MICORALIS Laboratory (EA 7354), Faculté d'Odontologie, Université de Nice-Sophia Antipolis; Pôle Odontologie, CHU NICE
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Gutknecht N, Al-Karadaghi TS, Al-Maliky MA, Conrads G, Franzen R. The Bactericidal Effect of 2780 and 940 nm Laser Irradiation on Enterococcus faecalis in Bovine Root Dentin Slices of Different Thicknesses. Photomed Laser Surg 2015; 34:11-6. [PMID: 26685038 DOI: 10.1089/pho.2015.3960] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The aim of this in vitro study was to investigate the antibacterial effect of the dual wavelength (2780 nm Er,Cr:YSGG and 940 nm diode) laser in elimination of Enterococcus faecalis in comparison with a 2780 nm Er,Cr:YSGG laser alone. BACKGROUND DATA Various laser wavelengths have been introduced as an adjunct in root canal treatment because of laser's bactericidal effect. MATERIALS AND METHODS Seventy- five slices of dentin with thicknesses of 300, 500, and 1000 μm (n = 25 each) obtained from caries-free bovine teeth were inoculated with 1 μL of E. faecalis suspension [1.67 × 10(7) colony-forming units (CFU)] and divided randomly into three groups: (A) samples indirectly irradiated with power settings of 1.06 W, 50 Hz, and 50 μs for Er,Cr:YSGG laser; (B) samples indirectly irradiated with Er,Cr:YSGG laser with the same power settings as group A and simultaneously with a 940 nm diode laser of 0.51 W in pulsed mode; and five samples from each thickness that were chosen as an unirradiated control group (Co). After irradiation, the CFU of E. faecalis were counted and the bacterial reduction was analyzed using Kruskal-Wallis nonparametric and post-hoc Dunnett tests. RESULTS There were statistical differences between groups A and B compared with the control group over all the three dentin slice thicknesses (p < 0.001). However, there was no statistical difference between groups A and B in killing of E. faecalis on 500 μm dentin slices. There were significantly more viable bacteria in group A than in group B in 300 and 1000 μm dentin slices (p < 0.01). CONCLUSIONS The results of this in vitro study showed that the dual wavelength laser system obtained a significantly higher bactericidal effect on E. faecalis than Er,Cr:YSGG laser, reaching a depth of 1000 μm of dentin.
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Affiliation(s)
- Norbert Gutknecht
- 1 Department of Conservative Dentistry, Periodontology and Preventive Dentistry, RWTH University Hospital Aachen , Aachen, Germany
| | - Tamara Sardar Al-Karadaghi
- 1 Department of Conservative Dentistry, Periodontology and Preventive Dentistry, RWTH University Hospital Aachen , Aachen, Germany .,2 Department of Biomedical Applications, Institute of Laser for Postgraduate Studies, University of Baghdad , Baghdad, Iraq
| | - Mohammed Abbood Al-Maliky
- 2 Department of Biomedical Applications, Institute of Laser for Postgraduate Studies, University of Baghdad , Baghdad, Iraq
| | - Georg Conrads
- 3 Division of Oral Microbiology and Immunology, Department of Conservative Dentistry, Periodontology and Preventive Dentistry, RWTH University Hospital Aachen , Aachen, Germany
| | - Rene Franzen
- 1 Department of Conservative Dentistry, Periodontology and Preventive Dentistry, RWTH University Hospital Aachen , Aachen, Germany
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Jhingan P, Sandhu M, Jindal G, Goel D, Sachdev V. An in-vitro evaluation of the effect of 980 nm diode laser irradiation on intra-canal dentin surface and dentinal tubule openings after biomechanical preparation: Scanning electron microscopic study. Indian J Dent 2015; 6:85-90. [PMID: 26097338 PMCID: PMC4455161 DOI: 10.4103/0975-962x.155889] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Context: Very recently, diode laser has been used for disinfecting the root canals in endodontic treatment and increasing its success rate and longevity utilizing the thermal effect of laser on surrounding tissues. Aims: The aim of this study is to evaluate the effect of 980 nm laser irradiation on intra-canal dentin surface – scanning electron microscopic (SEM) - in-vitro study. Methods: A total of 40 single-rooted freshly extracted permanent teeth were collected. Teeth were sectioned at the cemento-enamel junction using diamond disc. Root canals of all samples were prepared using hand ProTaper, which were randomly assigned into two groups (n = 20 each). Group 1: Receiving no treatment after biomechanical preparation; Group 2: 980 nm diode laser-treated root canals. Teeth were prepared for SEM analysis to check the size of intra-canal dentinal tubule openings. Statistical Analysis Used: Data were analyzed using SPSS V.16 software and compared using Levene's and independent t-test. Results: On statistical analysis, width of intracanal dentinal tubule openings in Group 1 (control) was significantly higher than those observed in Group 2 (diode laser-treated) (P < 0.001). Conclusion: This study showed that the application of 980 nm diode laser on intra-radicular dentin resulted in ultrastructural alterations resulting in melting of dentin.
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Affiliation(s)
- Pulkit Jhingan
- Department of Pedodotnics and Preventive Dentistry, ITS - CDSR, Muradnagar, Ghaziabad, (U.P.), India
| | - Meera Sandhu
- Department of Pedodotnics and Preventive Dentistry, ITS - CDSR, Muradnagar, Ghaziabad, (U.P.), India
| | - Garima Jindal
- Department of Pedodotnics and Preventive Dentistry, ITS - CDSR, Muradnagar, Ghaziabad, (U.P.), India
| | - Deepti Goel
- Department of Pedodotnics and Preventive Dentistry, ITS - CDSR, Muradnagar, Ghaziabad, (U.P.), India
| | - Vinod Sachdev
- Department of Pedodotnics and Preventive Dentistry, ITS - CDSR, Muradnagar, Ghaziabad, (U.P.), India
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Kuhn K, Rudolph H, Luthardt RG, Stock K, Diebolder R, Hibst R. Er:YAG Laser Activation of Sodium Hypochlorite for Root Canal Soft Tissue Dissolution. Lasers Surg Med 2013; 45:339-44. [DOI: 10.1002/lsm.22143] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/16/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Katharina Kuhn
- Center of Dentistry; Department of Prosthetic Dentistry, Ulm University; 89081 Ulm Germany
| | - Heike Rudolph
- Center of Dentistry; Department of Prosthetic Dentistry, Ulm University; 89081 Ulm Germany
| | - Ralph G. Luthardt
- Center of Dentistry; Department of Prosthetic Dentistry, Ulm University; 89081 Ulm Germany
| | - Karl Stock
- Institut für Lasertechnologien in der Medizin- und Messtechnik; Ulm University; 89081 Ulm Germany
| | - Rolf Diebolder
- Institut für Lasertechnologien in der Medizin- und Messtechnik; Ulm University; 89081 Ulm Germany
| | - Raimund Hibst
- Institut für Lasertechnologien in der Medizin- und Messtechnik; Ulm University; 89081 Ulm Germany
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Yao N, Zhang C, Chu C. Effectiveness of Photoactivated Disinfection (PAD) to Kill Enterococcus faecalis in Planktonic Solution and in an Infected Tooth Model. Photomed Laser Surg 2012; 30:699-704. [DOI: 10.1089/pho.2011.3216] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Na Yao
- The Second Dental Center, Peking University School and Hospital of Stomatology Beijing, China
| | - Chengfei Zhang
- Department of Endodontics, Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, China
| | - Chunhung Chu
- Oral Diagnosis and Polyclinic, Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, China
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Cheng X, Guan S, Lu H, Zhao C, Chen X, Li N, Bai Q, Tian Y, Yu Q. 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. Lasers Surg Med 2012; 44:824-31. [DOI: 10.1002/lsm.22092] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2012] [Indexed: 12/24/2022]
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Yamaguchi H, Kobayashi K, Nagano T, Shirakawa S, Gomi K, Hosoya N. Effects of Carbon Dioxide Laser Irradiation on Human Pulp Fibroblasts. J HARD TISSUE BIOL 2012. [DOI: 10.2485/jhtb.21.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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M. Jawad M, AbdulQader ST, Zaidan B, Zaidan A, AbdulQader IT, Naji A. An Overview: Laser Applications in Dentistry. INT J PHARMACOL 2011. [DOI: 10.3923/ijp.2011.189.197] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Yasuda Y, Kawamorita T, Yamaguchi H, Saito T. Bactericidal effect of Nd:YAG and Er:YAG lasers in experimentally infected curved root canals. Photomed Laser Surg 2010; 28 Suppl 2:S75-8. [PMID: 20738170 DOI: 10.1089/pho.2009.2554] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE The purpose of this study was to evaluate the bactericidal efficacy of Nd:YAG and Er:YAG laser in the experimentally infected curved root canals. BACKGROUND DATA Previous studies revealed that laser systems have a significant bactericidal effect in both human and bovine infected straight root canals. MATERIALS AND METHODS Sixty extracted single-rooted teeth with single root canals were selected and then instrumented with endodontic files to a size 60 (K-type file). The degree of root curvature was determined according to modified Schneider's method. Each of the specimens was incubated in a sterile centrifuge tube with 1 mL of the Enterococcus faecalis suspension at 37°C for 2 weeks under aerobic conditions. After laser irradiation at each of the two settings, 50 mJ, 10 pps (0.5 W) or 100 mJ, 10 pps (1.0 W), the number of E. faecalis in each root canal was examined. RESULTS In the straight root canals, the Er:YAG laser showed higher bactericidal effects by 6.4-10.8% than did the Nd:YAG laser. Conversely, the bactericidal effect of Er:YAG laser in the curved root canals was higher by 1.5-3.1% than was that with the Nd:YAG laser. The bactericidal effect of the Er:YAG laser in the curved root canal is significantly lower than that in the straight root canal (p < 0.05). CONCLUSION These results suggest that further development in the endodontic laser tip and technique is required to ensure its success in curved root canals sterilization.
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Affiliation(s)
- Yoshiyuki Yasuda
- Division of Clinical Cariology and Endodontology, Department of Oral Rehabilitation, School of Dentistry, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido, Japan.
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Junior JG, Marchesan MA, Souza-Gabriel AE, Vansan LP, Sousa-neto MD, Silva-Sousa YT. Ultra-Structural Changes at the Apical Stop Irradiated with CO2Laser. Photomed Laser Surg 2010; 28:345-9. [DOI: 10.1089/pho.2008.2473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- João Gonçalves Junior
- Department of Endodontics, University of Ribeirão Preto (UNAERP), Ribeirão Preto, SP, Brazil
| | - Melissa Andréia Marchesan
- Department of Endodontics, University of Ribeirão Preto (UNAERP), Ribeirão Preto, SP, Brazil
- Department of Endodontics, University of São Paulo (FORP-USP), Ribeirão Preto, SP, Brazil
| | | | - Luis Pascoal Vansan
- Department of Endodontics, University of Ribeirão Preto (UNAERP), Ribeirão Preto, SP, Brazil
| | - Manoel D. Sousa-neto
- Department of Endodontics, University of São Paulo (FORP-USP), Ribeirão Preto, SP, Brazil
| | - Yara T.C. Silva-Sousa
- Department of Endodontics, University of Ribeirão Preto (UNAERP), Ribeirão Preto, SP, Brazil
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Nomelini S, Souza-Gabriel A, Marchesan M, Sousa-Neto M, Silva-Sousa Y. Ultrastructural analysis of radicular dentine surface submitted to CO2laser at different parameters. Microsc Res Tech 2009; 72:737-43. [DOI: 10.1002/jemt.20723] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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17
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Franzen R, Esteves-Oliveira M, Meister J, Wallerang A, Vanweersch L, Lampert F, Gutknecht N. Decontamination of deep dentin by means of erbium, chromium:yttrium-scandium-gallium-garnet laser irradiation. Lasers Med Sci 2007; 24:75-80. [DOI: 10.1007/s10103-007-0522-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 10/22/2007] [Indexed: 11/28/2022]
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Abstract
The use of surgical lasers has been advocated to aid in the placement and second stage recovery of dental implants, together with soft tissue contouring. In addition, laser use has been suggested as an aid in decontamination of the implant surface in cases of peri-implantitis. In endodontics, the association of laser energy with dentine hypersensitivity, bacteriocidal action and pulp-capping, has led to a growing number of reports as to its beneficial use, together with claims of morphological changes in the canal wall, to enhance endodontic treatment success.
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Chiang YC, Lee BS, Wang YL, Cheng YA, Chen YL, Shiau JS, Wang DM, Lin CP. Microstructural changes of enamel, dentin-enamel junction, and dentin induced by irradiating outer enamel surfaces with CO2 laser. Lasers Med Sci 2007; 23:41-8. [PMID: 17384974 DOI: 10.1007/s10103-007-0453-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2006] [Accepted: 02/09/2007] [Indexed: 11/24/2022]
Abstract
The microstructural changes of enamel, dentin-enamel junction (DEJ), and dentin after CO(2) laser irradiation were studied. Buccal enamel surfaces of human third molars about 2 mm from the DEJ were irradiated, and the laser tip was moved 5 mm in a mesiodistal direction with 5 s of irradiation time. The output powers were 2 to 10 W in a continuous mode, and the average doses were approximately from 250 to 1,250 J/cm(2). All specimens were examined by a scanning electron microscope, and heat-transfer simulation was also applied to calculate temperature distribution. Surface ablation of enamel and separation of enamel and dentin along the DEJ were observed when the laser power output exceeded 3 W. Heat-transfer simulation indicated that dentin was prone to store more thermal energy than enamel. In conclusion, operation parameters of the CO(2) laser should be carefully selected to avoid thermal damage to the DEJ.
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Affiliation(s)
- Yu-Chih Chiang
- School of Dentistry and Graduate Institute of Clinical Dentistry, College of Medicine, National Taiwan University and National Taiwan University Hospital, Taipei, Taiwan, Republic of China
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Eldeniz AU, Ozer F, Hadimli HH, Erganis O. Bactericidal efficacy of Er,Cr:YSGG laser irradiation against Enterococcus faecalis compared with NaOCl irrigation: an ex vivo pilot study. Int Endod J 2007; 40:112-9. [PMID: 17229116 DOI: 10.1111/j.1365-2591.2006.01190.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIM To compare the efficacy of a standard NaOCl irrigation procedure with that of Er,Cr:YSGG laser irradiation in contaminated root canals having small and large apical foramina. METHODOLOGY Forty root canals of extracted central incisor teeth with straight roots were chosen so that their apical foramina just permitted the tip of a size 20-K file to pass through. The canals were then enlarged with files to size 60 and randomly divided into four groups of 10 teeth each. The apical foramina of one group were widened further so that the tip of a size 45-K file could just pass through. After sterilization, all roots were inoculated with Enterococcus faecalis for 48 h at 37 degrees C. The first group was used as a control, the second group was irrigated with 3% NaOCl solution for 15 min, and the last two groups having different sizes of apical foramina were irradiated with the Er,Cr:YSGG laser at output power from 0.5 W, with 20% air and water levels. The disinfecting efficacy of the groups was tested by collecting dentine chips from the inner canal walls of the specimens and counting viable E. faecalis on Mueller-Hinton agar plates. RESULTS The differences in the mean number of viable colonies between the control and laser groups were statistically significant (P < 0.05). The control specimens had the highest number of microorganisms (153 x 10(3) +/- 39 x 10(3)). Complete sterilization was achieved in the 3% NaOCl group. The mean colony forming units (CFU) values obtained after Er,Cr:YSGG laser irradiation were 6.6 x 10(3) CFU and 6.5 x 10(3) CFU in root canals having large and small apical foramina respectively. CONCLUSION In teeth with straight roots the Er,Cr:YSGG laser reduced the viable microbial population in root canals with small and large apical foramina but did not eradicate all bacteria. Three percent NaOCl inhibited the growth of E. faecalis and effectively sterilized all root canals.
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Affiliation(s)
- A U Eldeniz
- Department of Endodontics, Faculty of Dentistry, University of Selcuk, Konya, Turkey.
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21
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Horiba N, Itoh A, Yamaguchi M, Matsumoto T, Senda A, Nakamura H. Effects of intracanal carbon dioxide laser irradiation on cultured human fibroblasts. ACTA ACUST UNITED AC 2005; 100:767-71. [PMID: 16301161 DOI: 10.1016/j.tripleo.2005.01.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Accepted: 01/06/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate, under various conditions, the damage that might occur to viable cells after CO2 laser irradiation of the root canal. STUDY DESIGN A laser tip was placed within the root canal of extracted human teeth that were positioned above cultured fibroblasts (NB cells), and then irradiation was applied. The irradiation modes used were either pulse (40 pps) or super-pulse (151 pps). The laser energy was set at 32 J in both modes, and the tip of the laser beam was positioned to a point 2 mm from the fibroblasts. RESULTS When the pulse mode irradiation was applied, there was significant difference (P < .05) in the percentage of viable cells between teeth with closed apical foramen (1-mm wall between root canal and root apex) and the #15 group (No. 15 K-file used), #30 group (No. 30 K-file), or #50 group (No. 50 K-file). The difference between the #30 group and the #50 group (P < .05) was also significant. The larger the diameter of the apical foramen became, the lower was the percentage of viable cells. CONCLUSION If a CO2 laser irradiates a root canal system enlarged to within 1 mm of the root canal length, little damage to the periapical tissues would be expected to occur.
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Affiliation(s)
- Naoki Horiba
- Department of Endodontics, School of Dentistry, Aichi-Gakuin University, Nagoya, Japan.
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22
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Haapasalo M, Endal U, Zandi H, Coil JM. Eradication of endodontic infection by instrumentation and irrigation solutions. ACTA ACUST UNITED AC 2005. [DOI: 10.1111/j.1601-1546.2005.00135.x] [Citation(s) in RCA: 285] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lee MT, Bird PS, Walsh LJ. Photo-Activated Disinfection Of The Root Canal: A New Role For Lasers In Endodontics. AUST ENDOD J 2004; 30:93-8. [PMID: 15633797 DOI: 10.1111/j.1747-4477.2004.tb00417.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Because micro-organisms play a crucial role in the development of pulpal and periapical disease, the prognosis of endodontic therapy is intimately related to the presence of bacteria within the root canal system. Micro-organisms may persist in the apical region of the root canal system despite chemomechanical preparation. The usefulness of Class IV lasers (such as Nd:YAG, diode, KTP and Er:YAG) for photo-thermal disinfection of the root canal has been demonstrated in numerous studies. An alternative approach to microbial killing in the root canal system by laser light involves the use of low-power lasers to drive a photochemical reaction that produces reactive oxygen species, a technique termed photo-activated disinfection (PAD). By using exogenous photosensitisers such as tolonium chloride, killing of all types of bacteria can be achieved. In vitro studies of PAD have demonstrated its ability to kill photosensitised oral bacteria (such as E. faecalis), and more recently microbial killing in vivo in the root canal system has been demonstrated. While PAD can be undertaken as part of the routine disinfection of the root canal system, it also has potential use for eradicating persistent endodontic infections for which conventional methods have been unsuccessful.
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Abstract
With the rapid development of laser technology, new lasers with a wide range of characteristics are now available and being used in various fields of dentistry. In the past two decades, much experience and knowledge has been gained. This article provides an overview of the current and possible future clinical applications of lasers in endodontics, including their use in alleviating dentinal hypersensitivity, modification of the dentin structure, pulp diagnosis, pulp capping and pulpotomy, cleaning and shaping of the root canal system, and endodontic surgery. Endodontic procedures for which conventional treatments cannot provide comparable results or are less effective are emphasized.
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Affiliation(s)
- Adam Stabholz
- Izador I Cabakoff Center for Advanced and Continuing Education in Dentistry, The Hebrew University-Hadassah School of Dental Medicine, P.O. Box 12272, Jerusalem 91120, Israel.
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Esen E, Yoldas O, Kürkçü M, Doğan MC, Seydaoğlu G. Apical Microleakage of Root-End Cavities Prepared by CO2 Laser. J Endod 2004; 30:662-4. [PMID: 15329573 DOI: 10.1097/01.don.0000125316.89703.e2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This in vitro study in extracted human teeth was designed to compare the degree of dye penetration of root-end cavities prepared by CO2 laser, ultrasonic retrotip, or rotary instrument. Eighty-two human anterior teeth were prepared and obturated with laterally condensed gutta-percha and sealer. Root-end resection was performed at 90 degrees, 3 mm from apex. Root-end cavities were prepared by CO2 laser beam, ultrasonic retrotips, or bur and were filled with amalgam. The teeth were isolated and immersed in basic fuchsin at 36 degrees C for 48 hours. The roots were split longitudinally and examined by a stereomicroscope. Leakage was quantified by linear measurement of dye penetration with the aid of image-analyzing software. Apical leakage in the CO2 laser group was significantly less than in the ultrasonic retrotip and bur groups. The difference between the ultrasonic and bur groups was insignificant. Based on the results of this in vitro study, application of CO2 laser for root-end cavity preparation appears to decrease the apical leakage.
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Affiliation(s)
- Emin Esen
- Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Cukurova University, Adana, Turkey.
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26
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Perin FM, França SC, Silva-Sousa YTC, Alfredo E, Saquy PC, Estrela C, Sousa-Neto MD. Evaluation Of The Antimicrobial Effect Of Er:YAG Laser Irradiation Versus 1% Sodium Hypochlorite Irrigation For Root Canal Disinfection. AUST ENDOD J 2004; 30:20-2. [PMID: 15116905 DOI: 10.1111/j.1747-4477.2004.tb00162.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This laboratory study evaluated Er:YAG laser antibacterial action in infected root canals. Forty-eight maxillary central incisors were used. After canal preparation, the teeth were autoclaved and divided into four groups: (1) non-treated teeth (control group); (2) teeth treated with NaOCl; (3) teeth irradiated with Er:YAG laser (7 Hz, 100 mJ, 80 pulses/canal, 11 sec) to the working length; (4) teeth irradiated similarly to, but 3 mm short, of the apex. The root canals from Groups 2, 3 and 4 were inoculated with 4 bacteria: Bacillus subtillus, Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus, together with Candida albicans, and maintained for 24 h at 37 degrees C. All suspensions were adjusted to tube 2 of the MacFarland scale. The intracanal material was then collected with sterile paper points, which were placed in the canals for 5 min and then immersed in 5 ml of BHI medium. This was then seeded onto agar and stained by Gram's method. The NaOCl solutions and the Er:YAG laser irradiation to working length were effective against all five micro-organisms; however, 70% of the specimens irradiated 3 mm short of the apex remained infected.
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Affiliation(s)
- Fernanda M Perin
- Faculty of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
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Viducić D, Jukić S, Karlović Z, Bozić Z, Miletić I, Anić I. Removal of gutta-percha from root canals using an Nd:YAG laser. Int Endod J 2003; 36:670-3. [PMID: 14511223 DOI: 10.1046/j.1365-2591.2003.00710.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To examine the use of an Nd:YAG laser in removing gutta-percha fillings from root canals when used in conjunction with eucalyptol, dimethylformamide (DMF) or no solvent. METHODOLOGY Root-canal fillings (sealer and gutta-percha) were removed with laser irradiation of 20 Hz/1.5 W from 30 roots randomly divided in three groups. In group 1, the solvent was eucalyptol; in group 2, the solvent was DMF; and in group 3, no solvent was used. Laser irradiation was performed until the temperature measured on the root surface increased by 4 degrees C over room temperature. The treatment was deemed complete when the apical foramen was reached with the optical fibre and a reamer. The samples were split longitudinally, and the area of remaining gutta-percha on the root-canal walls was determined with the aid of a computer program. The total number of laser pulses to achieve length and the highest temperature recorded was determined for each tooth. The results were statistically analysed using Student's t-test (P < 0.05) for independent samples. RESULTS The average temperature increase in group 1 was 9.17 +/- 0.56 degrees C; in group 2, 9.56 +/- 0.28 degrees C; and in group 3, 8.29 +/- 0.41 degrees C. The shortest time to achieve length was in group 3 (6.4 +/- 0.49 min), then in group 1 (6.7 +/- 0.85 min) and group 2 (7.05 +/- 0.79 min). The area of remaining gutta-percha was the largest in group 2 (6.13 +/- 5.76%), whilst the smallest was for group 3 (4.69 +/- 4.03%), but the difference was not statistically significant. The number of pulses was not statistically significant between the groups. CONCLUSIONS Use of an Nd:YAG laser alone is capable of softening gutta-percha. The addition of solvents did not improve the retreatment, either in terms of the time required for the procedure or in terms of the area of remaining gutta-percha on root-canal walls.
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Affiliation(s)
- D Viducić
- Department of Microbiology, School of Dental Medicine, Tokushima University, Japan
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Kreisler M, Kohnen W, Beck M, Al Haj H, Christoffers AB, Götz H, Duschner H, Jansen B, D'Hoedt B. Efficacy of NaOCl/H2O2 irrigation and GaAlAs laser in decontamination of root canals in vitro. Lasers Surg Med 2003; 32:189-96. [PMID: 12605425 DOI: 10.1002/lsm.10148] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND OBJECTIVES To investigate the bactericidal effect of an 809 nm semiconductor laser alone, and in combination with NaOCl/H(2)O(2) irrigation in root canals in vitro. STUDY DESIGN/MATERIALS AND METHODS A total of 72 human single-rooted teeth extracted for periodontal reasons were included. The crowns were removed, the roots shortened to a length of 12 mm, and the canals enlarged up to an apical size of #50 file. The specimens were autoclaved and incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Laser irradiation was performed on a PC-controlled XY translation stage. A 200 micron optic fiber was used. Twelve specimens were irradiated at a power output of 1.5, 3.0, and 4.5 W in the cw-mode. The total irradiation time was 60 seconds per canal. Twelve specimens were rinsed with NaOCl and H(2)O(2) only, 12 were rinsed and laser treated, and 12 served as untreated controls. After laser treatment, the specimens were sonicated and the bacterial growth was examined by counting colony forming units on blood agar plates. Temperature changes at the outer root surface during irradiation were registered by means of thermocouples. Treated and control specimens were investigated by means of scanning electron microscopy. RESULTS Mean bacterial reductions of 0.35 log steps at a power output of 1.5 W, 1.44 at 3.0 W, and 2.84 at 4.5 W were calculated. Bacterial reduction by the NaOCl/H(2)O(2) solution alone was 1.48 and comparable to that achieved by irradiation at 3.0 W. With a log kill 2.85, the combination of rinsing and laser irradiation at 3.0 W resulted in a further significant bacterial reduction as compared to rinsing alone (P = 0.004). Irradiation did not result in excessive heat generation at the root surface. Carbonization of the root canal wall was observed in single teeth at 3.0 and 4.5 W and no controlled sealing of the dentinal tubules could be achieved in the root canal. CONCLUSIONS The application of the diode laser might be an adjunct to conventional endodontic treatment when used in combination with a NaOCl/H(2)O(2) solution.
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Affiliation(s)
- M Kreisler
- Department of Oral Surgery, Johannes Gutenberg-University, Mainz, Germany.
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Piccolomini R, D'Arcangelo C, D'Ercole S, Catamo G, Schiaffino G, De Fazio P. Bacteriologic evaluation of the effect of Nd:YAG laser irradiation in experimental infected root canals. J Endod 2002; 28:276-8. [PMID: 12043862 DOI: 10.1097/00004770-200204000-00004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The aim of this study was to evaluate the efficacy of the Pumped Diodium-Nd:YAG laser in sterilizing contaminated root canals. After hand instrumentation, 30 teeth were inoculated with Actinomyces naeslundii CH-12 and 30 teeth with Pseudomonas aeruginosa ATCC 27853 and incubated for 24 h. The teeth were divided into three subgroups: subgroup A received no treatment; subgroup B was irradiated with laser (5 Hz for 15 s or 10 Hz for 15 s); and subgroup C was irrigated with 5.25% NaOCl. The number of viable bacteria in each group was evaluated by using the surface-spread plate technique. The results indicated an average of 34.0% decrease in colony-forming units for A. naeslundii CH-12 and 15.7% for P. aeruginosa ATCC 27853 with the 5 Hz/15 s laser treatment, and for the 10 Hz laser frequency, a decrease of the 77.4% for A. naeslundii CH-12 and 85.8% for P. aeruginosa ATCC 27853. No bacteria were detected in the canals treated with 5.25% NaOCl. The results show an antibacterial effect of the Pumped Diodium Nd:YAG laser, depending on the radiation frequency. However, 5.25% NaOCl was more effective than either laser application.
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Affiliation(s)
- Raffaele Piccolomini
- Department of Biomedical Sciences, School of Medicine, G. d'Annunzio University, Chieti, Italy
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30
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Seal GJ, Ng YL, Spratt D, Bhatti M, Gulabivala K. An in vitro comparison of the bactericidal efficacy of lethal photosensitization or sodium hyphochlorite irrigation on Streptococcus intermedius biofilms in root canals. Int Endod J 2002; 35:268-74. [PMID: 11985679 DOI: 10.1046/j.1365-2591.2002.00477.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To compare the bacterial killing of Streptococcus intermedius biofilms in root canals using lethal photosensitization with various combinations of photosensitizer concentration and laser light dose or 3% sodium hypochlorite (NaOCl) irrigation. METHODOLOGY Extracted teeth (n = 35) with single canals were selected and the canals prepared to apical size 25 with a 10% taper. The teeth were autoclaved and the canals inoculated with Streptococcus intermedius in brain heart infusion broth and were incubated for 48 h to allow a biofilm to form. The teeth were then subjected to 3% NaOCl irrigation (n = 4) or lethal photosensitization using combinations of a range of toluidine blue O (TBO) photosensitizer concentrations (12.5, 25, 50, 100 microgram/mL-1) and light doses (60, 90, 120, 300, 600 s equivalent to energy doses of 2.1-21 J) using a 35-mW helium-neon low power laser targeted at the access cavity (n = 4 for each combination). Controls consisted of laser light only (TBO = 0 microgram/mL-1) (n = 4), TBO only (light dose = 0 s) (n = 4), and no treatment (positive control n = 17). Following treatment the canal contents were sampled with sterile paper points, the sample was dispersed in transport medium, serially diluted and cultured on blood agar to determine the number of colony forming units (CFU). RESULTS The combination of 100 microgram/mL-1 TBO and 600 s (21 J) of laser energy achieved maximum reduction in recovered viable bacteria (5 log10 CFU). TBO at low concentrations (< or =50 microgram/mL-1) was not bactericidal but treatment with 100 microgram/mL-1 TBO alone reduced recovered viable bacteria by 3 log10 CFU. Laser light alone had limited bactericidal effect. No viable bacteria were recovered following treatment with 3% NaOCl. CONCLUSIONS The combined use of a photosensitizing agent and a low power laser directed at the access cavity was bactericidal to S. intermedius biofilms in root canals but was unable to achieve total kill, unlike 3% NaOCl.
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Affiliation(s)
- G J Seal
- Department of Conservative Dentistry, Eastman Dental Institute for Oral Health Care Sciences, University College London, UK
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Abstract
The purpose of this study was to compare three methods of evaluation of the apical seal. Thirty-six teeth were prepared with a ProFile device and filled according to three filling methods: Thermafil (n = 12), warm vertical condensation (n = 12), and the single cone technique (n = 2). The apical seal was recorded with three methods, each successively used on the same teeth: a fluid filtration method, an electrochemical method, and a dye penetration study. The three methods of evaluation did not rank the apical leakage of the three filling techniques in the same order. The fluid filtration method showed that the vertical condensation was superior to Thermafil, which was in turn superior to the single cone technique (p = 0.04). The dye penetration study showed that the Thermafil was a better technique than the vertical condensation and the single cone technique (p = 0.005). The electrochemical method showed no statistical difference among the three filling techniques. No correlation was found among the results obtained with the three methods of evaluation. This study shows that several studies are necessary before comparing the apical seal obtained with various filling techniques.
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Affiliation(s)
- L Pommel
- Unité IMEB, Faculté d'Odontologie, Marseille, France
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