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Ohno H, Suzuki M, Shinkai K. The Effect of Laser Irradiation to Surfaces of Computer-Aided Design/Computer-Aided Fabrication Resin Blocks Coated with a Silane Coupling Agent on Bond Strength between the Resin Blocks and Composite Resin. Dent J (Basel) 2023; 11:290. [PMID: 38132428 PMCID: PMC10742938 DOI: 10.3390/dj11120290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/09/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023] Open
Abstract
The aim of this study was to investigate the effect of laser irradiation to computer-aided design/computer-aided fabrication (CAD/CAM) resin blocks coated with a silane coupling agent on the bond strength between resin blocks and composite resin. The CAD/CAM resin blocks used in this study were Cerasmart 300 (GC) and Vita Enamic (Vita); they were cut into plates and then subjected to a series of treatments. After processing with a silane coupling agent, treatment with a semiconductor laser was performed at 3.0, 5.0, and 7.0 W, followed by bonding procedures. The control group included those exposed to silane and bonded without laser application. After bonding, a mold with a simulated cavity was formed on the specimen and filled with flowable composite resin, and they were stored for 24 h or stressed by thermal cycling for subsequent testing that assessed the shear bond strength (n = 10). The results revealed that the bond strength was significantly enhanced by laser irradiation after applying a silane coupling agent (p < 0.03), whereas significant increase was not detected between the materials (p > 0.05). Particularly, 7 W laser irradiation had a significant increase on the bond strength between the composite resin and Cerasmart block after thermal cycling (p = 0.009). The SBS of the composite resin to CAD/CAM resin blocks was significantly enhanced by laser irradiation after silane coupling agent application.
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Affiliation(s)
- Hiroshi Ohno
- Advanced Operative Dentistry, Graduate School of Life Dentistry at Niigata, The Nippon Dental University, Niigata 951-8580, Japan;
| | - Masaya Suzuki
- Department of Operative Dentistry, School of Life Dentistry at Niigata, The Nippon Dental University, Niigata 951-8580, Japan;
| | - Koichi Shinkai
- Advanced Operative Dentistry, Graduate School of Life Dentistry at Niigata, The Nippon Dental University, Niigata 951-8580, Japan;
- Department of Operative Dentistry, School of Life Dentistry at Niigata, The Nippon Dental University, Niigata 951-8580, Japan;
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Almarsomy DH, Al-khayat FA, Al-Taee LA. The preventive/therapeutic effect of CO 2 laser and MI Paste Plus® on intact and demineralized enamel against Streptococcus mutans (In Vitro Study). Heliyon 2023; 9:e20310. [PMID: 37790956 PMCID: PMC10543189 DOI: 10.1016/j.heliyon.2023.e20310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 09/05/2023] [Accepted: 09/19/2023] [Indexed: 10/05/2023] Open
Abstract
Background To evaluate the preventive and therapeutic effects of CO2 laser and MI paste plus on intact and demineralized enamel surfaces and their impact on bacterial adhesion. Methods: 160 enamel slabs were prepared and randomly allocated into two main groups; sound and demineralized enamel (n = 80 per group), in which specimens were immersed in a demineralizing solution (50 mM acetic acid, pH 4.5) for 72 h at 37 °C. Each group was further divided into four subgroups (n = 20); the control (un treated surfaces), surfaces treated by CO2 laser, MI paste plus (Recaldent™, GC corporation/Germany), and those received a combination of CO2 and MI paste plus. Streptococcus Mutans biofilm was isolated, quantified, and then applied on treated enamel surfaces and incubated anaerobically for 24 h and then quantified by colony-forming unit (CFU). Meanwhile, surface changes were assessed by Vickers microhardness and Scanning Electron Microscope combined with Energy-Dispersive X-Ray Spectroscopy (SEM-EDX). Results: The combined use of CO2 laser followed by MI paste plus significantly (p < 0.000) enhanced surface microhardness of sound and demineralized enamel with a significant reduction in bacterial counts. However, each technique alone was beneficial as they exhibited higher microhardness with lower bacterial viability in comparison to the control. The treatment of demineralized enamel surfaces with MI paste significantly reduced the number of bacterial colonies with the presence of dispersed mineral deposits over the surface. Conclusions The combined use of CO2 laser and MI paste plus was effective as a preventive and/or therapeutic measures in enhancing surface properties of enamel and reducing the bacterial viability.
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Affiliation(s)
- Dhuha H. Almarsomy
- Department of Conservative and Aesthetic Dentistry, Baghdad College of Dentistry, University of Baghdad, Baghdad, Iraq
| | - Fadia A. Al-khayat
- Department of Basic Sciences, Baghdad College of Dentistry, University of Baghdad, Baghdad, Iraq
| | - Lamis A. Al-Taee
- Department of Conservative and Aesthetic Dentistry, Baghdad College of Dentistry, University of Baghdad, Baghdad, Iraq
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Damar S, Gümrü Çelikel AD, Pınar Erdem A. Comparative evaluation of fluoride-free remineralization agents with and without Er,Cr:YSGG laser on artificial enamel remineralization. Lasers Med Sci 2023; 38:172. [PMID: 37526766 DOI: 10.1007/s10103-023-03837-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 07/23/2023] [Indexed: 08/02/2023]
Abstract
This study aimed to evaluate the efficacy of fluoride-free remineralizing agents in initial enamel caries, with and without combined Er,Cr:YSGG laser application. The remineralization effect of various agents and their combinations on artificial initial caries was investigated using 10 experimental groups (n = 7): NC, negative control; PC, positive control; TM, calcium-phosphate compounds (CPP-ACP); TD, theobromine-containing toothpaste; RG, ROCS® remineralizing gel; L, Er,Cr:YSGG laser (2780 nm; 0.25 W; repetition rate, 20 Hz; pulse duration, 140 μs; tip diameter, 600 μm; without air/water cooling); L + fluoride toothpaste; L + TM; L + TD; and L + RG. The demineralized bovine enamel specimens were subjected to an 8-day pH cycle by daily application of the remineralizing agents and laser therapy once prior to the pH cycle and paste application. The enamel samples underwent the Vickers surface microhardness test, and one sample per group was analyzed with scanning electron microscopy. The Kruskal Wallis test was used to compare the microhardness recovery percentage (SMHR%) for each group, and multiple comparisons were made with the Dunn test. Groups L (p = 0.003), RG (p = 0.019), L + TM (p < 0.001), L + fluoride toothpaste (p = 0.001),and L + RG (p = 0.036) exhibited significant increase in SMHR%. The tested remineralizing agents exhibited no statistically significant difference in effect when used alone and in combination with Er,Cr:YSGG laser. Combined application of Er,Cr:YSGG laser and ROCS® remineralization gel effectively promoted enamel remineralization, while use of CPP-ACP and fluoride toothpaste alone was ineffective. Theobromine-containing toothpaste exhibited the least SMHR%. Long-term evaluation of these agents is recommended.
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Affiliation(s)
- Serhat Damar
- Department of Pediatric Dentistry, Faculty of Dentistry, Istanbul University, Istanbul, Turkey
| | | | - Arzu Pınar Erdem
- Department of Pediatric Dentistry, Faculty of Dentistry, Istanbul University, Istanbul, Turkey
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Singh K, Jhingan P, Malik M, Mathur S. In vitro comparative evaluation of physical and chemical properties of surface enamel after using APF and SDF with or without laser activation. Eur Arch Paediatr Dent 2023:10.1007/s40368-023-00808-z. [PMID: 37296235 DOI: 10.1007/s40368-023-00808-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023]
Abstract
PURPOSE To evaluate and compare the changes in physical and chemical properties of the enamel surface after application of Silver Diamine Fluoride (SDF), Acidulated Phosphate Fluoride (APF), LASER activated SDF and LASER activated APF. METHODS Sample consisted of 72 freshly extracted healthy human premolar teeth, extracted for orthodontic purpose, free from caries, fracture or any anomalies. The selected samples were randomly divided into four groups (n = 18): Group 1 (SDF); Group 2 (APF); Group 3 (LASER activated SDF) and Group 4 (LASER activated APF). All samples were evaluated for values of DIAGNOdent at baseline, after demineralisation and after remineralisation. They were further divided and assessed for colour changes, surface alterations and fluoride content of surface enamel using Spectrophotometer, Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometry respectively. The statistical analysis was done using One-Way ANOVA, Tukey's HSD test, Mann-Whitney U test and Kruskal-Wallis Test. RESULTS Highest remineralising potential and maximum colour changes of surface enamel was exhibited by Group 3. Scanning Electron Micrographs of Group 3 and Group 4 exhibited regular globular structures of enamel whereas Group 1 and Group 2 showed irregular globular surface of the enamel at 2000× and 5000× magnification. Maximum fluoride uptake on the surface enamel was seen in Group 4 followed by Group 3. CONCLUSION Use of LASER activated topical fluorides helps to achieve superior caries prevention. LASER activated APF can be used as an aesthetic alternative to SDF, as LASER activated APF showed higher uptake of fluoride on the enamel surface without discoloration effect.
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Affiliation(s)
- K Singh
- Department of Pediatric and Preventive Dentistry, ITS-CDSR, Muradnagar, Ghaziabad, India.
| | - P Jhingan
- Department of Pediatric and Preventive Dentistry, ITS-CDSR, Muradnagar, Ghaziabad, India
| | - M Malik
- Department of Pediatric and Preventive Dentistry, ITS-CDSR, Muradnagar, Ghaziabad, India
| | - S Mathur
- Department of Pediatric and Preventive Dentistry, ITS-CDSR, Muradnagar, Ghaziabad, India
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Xue VW, Yin IX, Niu JY, Chan A, Lo ECM, Chu CH. Combined Effects of Topical Fluorides and Semiconductor Lasers on Prevention of Enamel Caries: A Systematic Review and Meta-Analysis. Photobiomodul Photomed Laser Surg 2022; 40:378-386. [PMID: 35587640 DOI: 10.1089/photob.2021.0184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Objective: To compare the effects of combined treatment of topical fluoride and semiconductor laser (F&L) with topically using fluoride (F) on remineralization and prevention of enamel caries. Background: There is no agreement on whether semiconductor lasers can promote the effect of topical fluoride on the remineralization and prevention of dental caries. This study is the first systematic review and meta-analysis to investigate the pooled effect of data from studies that compared the combined use of semiconductor lasers and topical fluorides with the single use of fluoride on remineralization and prevention of caries. Methods: We performed literature search on Scopus, Web of Science, and PubMed. The keywords were as follows: ((diode lasers) OR (diode laser) OR (quantum cascade laser) OR (quantum cascade lasers) OR (Gallium Aluminum Arsenide lasers) OR (Gallium Aluminum Arsenide laser) OR (GaAlAs lasers) OR (GaAlAs Laser) OR (semiconductor laser) OR (semiconductor lasers)) AND ((caries) OR (dental caries) OR (remineralisation) OR (remineralization) OR (demineralization) OR (demineralisation)) AND fluoride. We carried out meta-analysis to compare the microhardness of demineralized enamel, lesion depth (LD), and percent reduction of calcium (Ca%) of sound enamel receiving F&L with F. Results: The search identified nine laboratory studies, which used 445 to 980 nm semiconductor lasers with various fluorides. The standard mean difference of microhardness of demineralized enamel between F&L and F was 1.06 [95% confidence interval (CI): 0.12 to 2.00, p = 0.03]. No difference was found in LD (95% CI: -1.63 to 0.10, p = 0.08) and Ca% (95% CI: -0.52 to 1.28, p = 0.40) on sound enamel between the two groups. Conclusions: Semiconductor lasers enhance the effect of fluoride on remineralizing but not on preventing enamel caries. Moreover, substantial heterogeneity was found among the studies, and the results should be interpreted cautiously.
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Affiliation(s)
| | - Iris Xiaoxue Yin
- Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong
| | - John Yun Niu
- Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong
| | - Ambrose Chan
- Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong
| | | | - Chun Hung Chu
- Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong
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Zaleh AA, Vaziri AS, Pourhajibagher M, Bahador A. The synergistic effect of Nano-propolis and curcumin-based photodynamic therapy on remineralization of white spot lesions: An ex vivo study. Photodiagnosis Photodyn Ther 2022; 38:102789. [DOI: 10.1016/j.pdpdt.2022.102789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 10/19/2022]
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Enamel Erosion Reduction through Coupled Sodium Fluoride and Laser Treatments before Exposition in an Acid Environment: An In Vitro Randomized Control SEM Morphometric Analysis. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12031495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
(1) Background: Erosive lesions of dental enamel are steadily increasing owing to both the availability of exogenous acid and the production of endogenous acid. The aim of this study was to investigate the erosion-inhibiting potential of a diode laser irradiation and topical application of fluoride used alone or in combination on the enamel surface of extracted teeth before exposure to an acidic solution. (2) Methods: The four axial enamel surfaces of 40 healthy molars were used for four study groups: (A) no treatment; (B) application of fluoride gel for 120 s; (O) a diode laser application for 120 s; and (X) a combined laser/fluoride for 120 s. Each enamel surface was examined by SEM (scanning electron microscopy). (3) Results: At 700× magnification, it was possible to detect the enamel prisms of the test area of groups A, B, and O, while no structures such as enamel prisms were highlighted for group X because they were covered by an amorphous layer. The mean number of prisms ×1000 µm2 was 7.2 units with an SD of 0.72 for group A, 8 units with an SD of 0.96 for group B, and 4.8 units with a SD of 0.4 for group O. Student’s t-test showed no significant difference between group A and B with a p = 0.054. Group O showed a significant reduction of prims ×1000 µm2 compared with group A (p = 0.0027) and group B (p = 0.0009). Student’s t-test showed no significant difference between groups A and B with a p = 0.054. Group O showed a significant reduction of prims density with respect to group A (p = 0.0027) and group B (p = 0.0009). (4) Conclusions: This amorphous layer might be correlated with the effect of laser on enamel, which reduces both water and carbonate ion; increases the crystallinity of hydroxyapatite, and improves the mechanical properties of enamel; which is responsible for greater protection expressed by the enamel of group X against acid attacks.
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Alqahtani MA, Almosa NA, Alsaif KA, Alsaif NM, Aljaser YJ. Effect of topical fluoride application and diode laser-irradiation on white spot lesions of human enamel. Saudi Dent J 2021; 33:937-943. [PMID: 34938035 PMCID: PMC8665184 DOI: 10.1016/j.sdentj.2021.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 07/02/2021] [Accepted: 08/16/2021] [Indexed: 12/01/2022] Open
Abstract
Objectives This study aims to evaluate the effectiveness of topical fluoride application and diode laser-irradiation on the hardness of demineralized enamel and to evaluate the esthetic improvement of the white spot lesions (WSLs) using a visual analog scale (VAS). Materials and Methods Artificial WSLs (3x3 mm) were created on the enamel surface of 45 human third molars. The teeth were randomly assigned into three groups (n = 15): group A, fluoride only; group B, combined therapy of fluoride and diode laser; and group C, control. Vicker’s hardness number (VHN) was measured at baseline, after demineralization and after treatment. To evaluate the esthetic improvement after treatment, 14 raters evaluated each group’s photographs using a 100-millimeter VAS. A one-way ANOVA or Brown-Forsythe and Games-Howell post hoc procedure were performed for statistical analysis. The level of significance was set at α = 0.05 for all tests. Results Group A mean VHN was significantly higher than groups B and C, and group B was significantly higher than group C (P < 0.05). However, the mean VAS rating for the combined therapy group (B) was significantly higher than that for groups A and C (P < 0.05). Conclusion Combination therapy significantly improved the esthetic appearance of WSLs compared to the fluoride only group. However, there was less enamel hardness versus treatment with fluoride only.
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Affiliation(s)
- Mohammad A Alqahtani
- Department of Dentistry, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Naif A Almosa
- Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Khalid A Alsaif
- Prosthodontics Department, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Naif M Alsaif
- King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Yazeed J Aljaser
- Orthodontic Resident, College of Dentistry, Taibah University, Madina, Saudi Arabia
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Zhao IS, Xue VW, Yin IX, Niu JY, Lo ECM, Chu CH. Use of a novel 9.3-μm carbon dioxide laser and silver diamine fluoride: Prevention of enamel demineralisation and inhibition of cariogenic bacteria. Dent Mater 2021; 37:940-948. [PMID: 33707067 DOI: 10.1016/j.dental.2021.02.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/16/2021] [Accepted: 02/24/2021] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To investigate the effects of a 9.3-μm carbon dioxide (CO2) laser and silver diamine fluoride (SDF) on the prevention of enamel demineralisation and inhibition of cariogenic bacteria. METHODS Enamel blocks were applied with Laser (Group-1), SDF (Group-2), Laser + SDF (Group-3) and no treatment (Group-4), and then subjected to an 8-day pH-cycling for cariogenic challenge. Lesion depth and cross-sectional micro-hardness were assessed. Surface morphological and chemical changes were studied using scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS). For the antibacterial activity, treated enamel blocks were incubated with Streptococcus mutans. The biofilm morphology, kinetics and viability were assessed by SEM, colony-forming units (CFUs) and confocal laser scanning microscope (CLSM), respectively. RESULTS Lesion depths (μm) for Group-1 to Group-4 were 88 ± 21, 26 ± 11, 13 ± 9 and 115 ± 25, respectively (p < 0.001; Group-2 and Group-3 < Group-1 < Group-4). Group-3 had a significantly higher cross-sectional micro-hardness than the other three groups. EDS determined that Group-4 had the lowest calcium-to-phosphorus molar ratio among the groups (p < 0.001). SEM images showed apparent bacteria accumulation on enamel surfaces in Group-4, but not in other groups. Log CFUs for Group-1 to Group-4 were 6.2 ± 0.6, 2.9 ± 0.8, 2.2 ± 1.1 and 7.3 ± 0.3, respectively (p < 0.001; Group-2 and Group-3 < Group-1 < Group-4). CLSM images revealed that live bacteria dominated in Group-4, but not in other groups. SIGNIFICANCE The irradiation with a 9.3-μm CO2 laser alone can prevent the demineralisation of enamel and reduce the adhesion of cariogenic bacteria. Moreover, adding SDF can significantly increase the preventive effect and antibacterial ability.
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Affiliation(s)
- Irene Shuping Zhao
- School of Dentistry, Shenzhen University Health Science Center, Shenzhen 518000, China
| | - Vicky Wenqing Xue
- Faculty of Dentistry, The University of Hong Kong, Hong Kong 999077, China
| | - Iris Xiaoxue Yin
- Faculty of Dentistry, The University of Hong Kong, Hong Kong 999077, China
| | - John Yun Niu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong 999077, China
| | - Edward Chin Man Lo
- Faculty of Dentistry, The University of Hong Kong, Hong Kong 999077, China
| | - Chun Hung Chu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong 999077, China.
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Badreddine AH, Couitt S, Donovan J, Cantor-Balan R, Kerbage C, Rechmann P. Demineralization Inhibition by High-Speed Scanning of 9.3 µm CO 2 Single Laser Pulses Over Enamel. Lasers Surg Med 2020; 53:703-712. [PMID: 33161599 DOI: 10.1002/lsm.23340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND OBJECTIVE In vitro studies were conducted to evaluate the use of an automated system for high-speed scanning of single 9.3 µm CO2 laser pulses in the inhibition of caries-like lesion formation in the enamel of extracted human molars. The effect of the laser in generating an acid-resistant layer and the effect of the layer on inhibiting surface mineral loss during pH cycling was explored. STUDY DESIGN/MATERIALS AND METHODS Laser irradiation was performed with fluences of 0.6, 0.8, and 1.0 J/cm2 for single pulses of 1 mm diameter (1/e2 ), with pulse durations of 17, 22, and 27 microseconds, respectively. The laser was scanned at a 750 Hz pulse repetition rate in an automated pattern covering an area of 7 mm2 in 0.3 sec. Six treatment groups were investigated: three groups for each fluence for laser-only and three for laser irradiation with additional fluoride from a toothpaste slurry (sodium fluoride at 1100 ppm). Each group used non-irradiated areas, which included untreated controls for the laser-only groups and a fluoride-only treatment for the groups with additional fluoride. pH cycling was performed on both groups, followed by microhardness testing to determine the relative mineral loss (∆Z) from a caries-like formation and surface mineral loss (∆S). RESULTS Laser irradiation with the 9.3 µm CO2 laser generated an acid-resistant layer of about 15 µm in depth. For the laser-irradiated samples with additional fluoride application, the relative mineral loss (∆Z) was 113 ± 63 vol%-µm, while for those with only fluoride application ∆Z was 572 ± 172 vol%-µm. At the highest fluence (1.0 J/cm2 ) used, an 80.2% inhibition of caries-like lesion was measured by ∆Z. Using only laser irradiation at the highest fluence resulted in an inhibition of caries-like lesion of 79.5% for the irradiated samples (∆Z = 374 ± 149 vol%-µm) relative to the control (∆Z = 1826 ± 325 vol%-µm). Surface microhardness tests resulted in an inhibition of surface softening, as measured by the Knoop Hardness Value (KHN) (108 ± 33 KHN for laser irradiated with additional fluoride, for non-irradiated controls with fluoride only 52 ± 16 KHN). Inhibition of surface loss was observed for all laser fluences, but the maximum surface loss for the untreated control group was only 2.2 ± 0.49 µm. CONCLUSIONS The results demonstrate a significant benefit of the 9.3 µm CO2 laser at fluences of 0.6, 0.8, and 1.0 J/cm2 in caries-like lesion inhibition as measured by the relative mineral loss in depth and surface mineral loss, without significant damage to the enamel. Additionally, inhibition of surface softening and surface loss during pH cycling was observed. The surface loss was small compared with the overall lesion depth and thickness of the generated acid-resistant layer. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
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Affiliation(s)
- Ali H Badreddine
- Convergent Dental, Inc., 140 Kendrick St Bldg C3, Needham, Massachusetts, 02494
| | - Stephen Couitt
- Convergent Dental, Inc., 140 Kendrick St Bldg C3, Needham, Massachusetts, 02494
| | - Julia Donovan
- Convergent Dental, Inc., 140 Kendrick St Bldg C3, Needham, Massachusetts, 02494
| | - Roni Cantor-Balan
- Convergent Dental, Inc., 140 Kendrick St Bldg C3, Needham, Massachusetts, 02494
| | - Charles Kerbage
- Convergent Dental, Inc., 140 Kendrick St Bldg C3, Needham, Massachusetts, 02494
| | - Peter Rechmann
- Department of Preventive and Restorative Dental Sciences, School of Dentistry, University of California at San Francisco, 707 Parnassus Avenue, San Francisco, California, 94143
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Combined effects of a topical fluoride treatment and 445 nm laser irradiation of enamel against a demineralization challenge: A light and electron microscopic ex vivo study. PLoS One 2020; 15:e0237195. [PMID: 32764819 PMCID: PMC7413416 DOI: 10.1371/journal.pone.0237195] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/21/2020] [Indexed: 11/19/2022] Open
Abstract
This study investigated the caries-preventive effect of 445 nm laser radiation in combination with fluoride on the prevention of white spot lesions. Previously, several studies have indicated the ability of 488 nm argon ion laser irradiation to reduce early enamel demineralization. A diode laser (445 nm) could be an alternative technology for possible caries-preventive potential. Each sample of a group of seventeen caries-free bovine teeth was treated in four different ways on four different zones of the labial surface: control/no treatment (C), laser irradiation only (L) (0.3 W, 60 s and applied dose of 90 J/cm2), amine fluoride application only (10,000 ppm and pH 3.9) (F), and amine fluoride application followed by laser irradiation (FL). After treatment, the teeth were subjected to a demineralization solution (pH 4.3 for 48 h at 37 °C) to induce subsurface lesions. After sectioning, the teeth were examined by light microscopy. Three teeth were analyzed by scanning electron microscopy (SEM). The depths of the subsurface lesions in the C, L, F, and FL groups were 103.01 (± 13.04), 96.99 (± 14.51), 42.59 (± 17.13), and 24.35 (± 11.38) μm, respectively. The pairwise group comparison showed the following results: p < 0.001 for FL versus C, FL versus L, F versus C, and F versus L, p = 0.019 for FL versus F and p = 0.930 for L versus C. The SEM micrographs support the light-microscopic examination. The results of the current study have shown that using relatively low irradiation settings of 445 nm laser on fluoridated enamel may be effective for prevention of white spot lesions.
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Moharam LM, Sadony DM, Nagi SM. Evaluation of diode laser application on chemical analysis and surface microhardness of white spots enamel lesions with two remineralizing agents. J Clin Exp Dent 2020; 12:e271-e276. [PMID: 32190198 PMCID: PMC7071531 DOI: 10.4317/jced.56490] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 01/08/2020] [Indexed: 11/05/2022] Open
Abstract
Background To investigate the effect of diode laser application and two commercial remineralizing agents on the remineralization and surface microhardness of white spot enamel lesions. Material and Methods Sixty specimens were prepared then equally divided into six groups (n=10/group), according to the diode laser and the two commercial remineralizing agents applied to demineralized enamel surfaces (APF gel and sodium fluoride NaF mousse) with or without diode Laser application as follows; Group A; control, Group B; diode Laser application, Group C; APF gel application, Group D; NaF mousse application, Group E; APF gel application + diode Laser, Group F; NaF mousse application+ diode Laser. Then the teeth were investigated for their Ca, P & F ions content and surface microhardness. One-way ANOVA followed by Tukey's (HSD) post hoc test were used for statistical analysis. Results Ca ion wt% showed no statistically significant difference between tested groups, with the highest mean value recorded with Group C. P ion wt%, showed a statistically significant difference between Groups A and C, and the highest mean value was recorded for Group A. The highest F ion wt% was recorded for Group C, while the lowest was recorded for both A and B groups. The highest significant microhardness mean values was recorded for Group E, while the lowest was recorded for Group A. Conclusions Diode Laser treatment of the demineralized enamel surface had a positive influence on the chemistry and surface microhardness and it may represent a promising adjunct for enamel surface remineralization. Key words:Diode Laser application, chemical analysis, surface microhardness, remineralizing agents, white spot lesions.
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Affiliation(s)
| | - Doaa-Mohamed Sadony
- Restorative and Dental Materials department, National Research Centre, Giza, Egypt
| | - Shaymaa-Mohamed Nagi
- Restorative and Dental Materials department, National Research Centre, Giza, Egypt
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Rafiei E, Fadaei Tehrani P, Yassaei S, Haerian A. Effect of CO 2 laser (10.6 μm) and Remin Pro on microhardness of enamel white spot lesions. Lasers Med Sci 2020; 35:1193-1203. [PMID: 32006264 DOI: 10.1007/s10103-020-02970-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/22/2020] [Indexed: 11/28/2022]
Abstract
This study investigated the combined effect of CO2 laser irradiation and Remin Pro paste on microhardness of enamel white spot lesions (WSLs). Seventy-eight intact premolars were randomly assigned into six groups and then stored in a demineralizing solution to create WSLs. Afterwards, the teeth in group 6 (negative control) remained untreated, while groups 1 and 4 were exposed to CO2 laser irradiation (20 Hz, 1 W, 30 s) and Remin Pro paste, respectively. In groups 2 and 3, the teeth were exposed to laser either before (group 2) or after (group 3) Remin Pro application. The teeth in groups 1 to 5 were then immersed in artificial saliva for 90 days while subjected to fluoride mouthwash and weekly brushing. Finally, the teeth were sectioned, and Vickers microhardness was measured at the enamel surface and at 50, 100, and 150 μm from the surface. One sample of each group was also examined with scanning electron microscope (SEM). Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test. The significance was set at 0.05. Laser irradiation followed by Remin Pro application (group 2) caused a significant increase in total WSLs' microhardness compared with laser alone (group 1) and control groups (P < 0.05). Microhardness at depths of 100 and 150 μm was also significantly greater in group 2 compared with those of group 3 and control groups (P < 0.05). Combined application of CO2 laser with Remin Pro paste, when laser is irradiated before the paste, is suggested for re-hardening of WSLs in deep layers of enamel.
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Affiliation(s)
- Elahe Rafiei
- Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Pooya Fadaei Tehrani
- Dental Students Research Center, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
| | - Soghra Yassaei
- Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Alireza Haerian
- Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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Brandão CB, Corona SAM, Torres CP, Côrrea-Marques AA, Saraiva MCP, Borsatto MC. Efficacy of CO lasers in preventing dental caries in partially erupted first permanent molars: a randomized 18-month clinical trial. Lasers Med Sci 2020; 35:1185-1191. [PMID: 31970563 DOI: 10.1007/s10103-020-02967-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 01/13/2020] [Indexed: 12/19/2022]
Abstract
The aim of this controlled randomized double-blinded clinical trial was to evaluate the use of a CO2 laser with or without topical application of acidulated fluorides in the prevention of dental caries in partially erupted first permanent molars. We selected 61 healthy children at high risk of caries, all between 6 and 8 (7.1 ± 0.8) years of age and with 4 partially erupted first permanent molars. A CO2 laser device emitting at 10.6 μm was used (0.5 W, 0.05 mJ per pulse, 10 kHz). Each first molar in an individual was randomly assigned to one treatment: (L) CO2 laser (0.066 J/cm2); (FL) 1.23% acidulated fluoride gel and CO2 laser (0.066 J/cm2); (V) 5% fluoride varnish, or (S) sealant (control). Patients were followed-up at 3, 6, 12, and 18 months after treatment, through direct visual examination and by an operator blinded to the treatments (kappa ≥ 0.70). The International Caries Detection and Assessment System (ICDAS-II) index was used to assess the soundness of tooth structure or the presence of white spot lesions, cavitated enamel, and/or dentin lesions. The Yildiz Visual Index was used to evaluate sealant retention. Results were evaluated using Kaplan-Meier survival analysis, and the hazard ratio of the treatments was estimated using shared frailty models with a gamma distribution, which considered the patient as a cluster. There were no significant differences among treatments compared to sealants. After 18 months, the use of a CO2 laser with or without acidulated fluorides was shown to be effective in preventing caries on the occlusal surface of partially erupted permanent first molars in children at high risk for caries.
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Affiliation(s)
- Cristina Bueno Brandão
- Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Silmara Aparecida Milori Corona
- Department of Restorative Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Carolina Paes Torres
- Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Alessandra Afonso Côrrea-Marques
- Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Maria Conceição Pereira Saraiva
- Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Maria Cristina Borsatto
- Department of Pediatric Dentistry, Ribeirão Preto School of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
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Loiola ABDA, Aires CP, Curylofo-Zotti FA, Rodrigues Junior AL, Souza-Gabriel AE, Corona SAM. The Impact of CO 2 Laser Treatment and Acidulated Phosphate Fluoride on Enamel Demineralization and Biofilm Formation. J Lasers Med Sci 2019; 10:200-206. [PMID: 31749946 DOI: 10.15171/jlms.2019.32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: This study evaluated the impact of CO2 laser treatment and acidulated phosphate fluoride (APF) on enamel demineralization and biofilm formation, using in vitro and in situ designs. Methods: Demineralized enamel slabs were distributed among 8 groups: placebo, placebo + continuous CO2 laser, placebo + repeated CO2 laser, placebo + ultrapulsed CO2 laser, 1.23% APF, APF + continuous CO2 laser, APF + repeated CO2 laser and APF + ultrapulsed CO2 laser. In the in vitro study, 15 enamel slabs from each group were subjected to a pH-cycling regimen for 14 days. In the cross over in situ design, 11 volunteers wore palatal appliances with demineralized enamel slabs for 2 periods of 14 days each. Drops of sucrose solution were dripped onto enamel slabs 8×/day. Biofilms formed on slabs were collected and the colony-forming units (CFU) of Streptococcus mutans and Lactobacillus were determined. Results: For both in vitro and in situ studies, there was no significant difference between treatments (P>0.05). However, all treatments increased microhardness of demineralized enamel (P<0.05). After a further in situ cariogenic challenge, with the exception of the placebo, all treatments maintained microhardness values (P<0.05). Microbiological analysis showed no difference in Streptococcus mutans (P>0.05) or Lactobacillus (P>0.05) counts between groups. Conclusion: The results suggest that APF gel combined with the CO2 laser, regardless of the pulse emission mode used, was effective in controlling enamel demineralization, but none of the tested treatments was able to prevent bacterial colonization.
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Affiliation(s)
- Ana Bárbara de Araújo Loiola
- Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil, 14040-904
| | - Carolina Patrícia Aires
- Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirão Preto-SP, Brazil, 14040-904
| | - Fabiana Almeida Curylofo-Zotti
- Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil, 14040-904
| | - Antônio Luiz Rodrigues Junior
- Department of Social Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil, 14049- 900
| | - Aline Evangelista Souza-Gabriel
- Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil, 14040-904
| | - Silmara Aparecida Milori Corona
- Department of Restorative Dentistry, Dental School of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil, 14040-904
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Al-Maliky MA, Frentzen M, Meister J. Laser-assisted prevention of enamel caries: a 10-year review of the literature. Lasers Med Sci 2019; 35:13-30. [PMID: 31399861 DOI: 10.1007/s10103-019-02859-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 08/01/2019] [Indexed: 01/13/2023]
Abstract
Since the invention of lasers in dentistry, investigations in caries prevention by the use of laser radiation have been proposed. There are several mechanisms stated for this purpose such as photothermal and/or photochemical interaction processes with the enamel. Alone or in conjugation with topical fluoride application, this treatment modality may improve enamel acid resistance in high-caries-risk populations. Data collection was done by searching the keywords caries, prevention, and laser in PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar. Lasing protocols of the collected literature and their effectiveness as well as examination methods used to verify treatment outcomes have been evaluated. One hundred eighteen publications were found for the last 10 years. The wavelengths investigated for caries prevention are mainly located in the near and the mid-infrared spectral range. In the evaluated period of time, investigations using CO2; Er:YAG; Er,Cr:YSGG; Er:YLF; fundamental, second, and third harmonic generations of Nd:YAG; diodes; and argon ion lasers were found in the databases. Accounting for 39% of the literature, CO2 laser was the most examined system for this purpose. Reviewing the literature in this narrative review showed that all laser systems presented a positive effect in varying degrees. Laser irradiation could be an alternative or synergistic to topical fluoridation for enamel caries prevention with longer lasting effect. Further research should be focused on selecting proper laser settings to avoid damage to enamel and developing effective evidence-based clinical protocols.
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Affiliation(s)
- Mohammed Abbood Al-Maliky
- Department of Periodontology, Operative and Preventive Dentistry, Dental Faculty, University of Bonn, Welschnonnenstrasse 17, 53111, Bonn, Germany. .,Center of Applied Medical Laser Research and Biomedical Optics (AMLaReBO), University of Bonn, Bonn, Germany. .,Department of Biomedical Applications, Institute of Laser for Postgraduate Studies, University of Baghdad, Baghdad, Iraq.
| | - Matthias Frentzen
- Department of Periodontology, Operative and Preventive Dentistry, Dental Faculty, University of Bonn, Welschnonnenstrasse 17, 53111, Bonn, Germany
| | - Jörg Meister
- Department of Periodontology, Operative and Preventive Dentistry, Dental Faculty, University of Bonn, Welschnonnenstrasse 17, 53111, Bonn, Germany.,Center of Applied Medical Laser Research and Biomedical Optics (AMLaReBO), University of Bonn, Bonn, Germany
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Soltanimehr E, Bahrampour E, Yousefvand Z. Efficacy of diode and CO 2 lasers along with calcium and fluoride-containing compounds for the remineralization of primary teeth. BMC Oral Health 2019; 19:121. [PMID: 31217005 PMCID: PMC6585004 DOI: 10.1186/s12903-019-0813-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 06/03/2019] [Indexed: 11/30/2022] Open
Abstract
Background This study aimed to assess the efficacy of a 980-nm diode and 10.6-μm CO2 laser accompanied by tricalcium phosphate-5% sodium fluoride (fTCP) and casein phosphopeptide amorphous calcium phosphate (CPP-ACP) for the remineralization of primary teeth. Methods In total, 117 extracted primary anterior teeth were randomly divided into eight experimental and one control group: (I) control (polished enamel), (II) fTCP varnish, (III) fTCP + diode laser, (IV) fTCP + CO2 laser, (V) CPP-ACP, (VI) CPP-ACP + diode laser, (VII) CPP-ACP + CO2 laser, (VIII) diode laser, and (IX) CO2 laser. The microhardness of 12 samples in each group and the enamel porosity of one sample in each group were assessed before and after demineralization and 28 days after remineralization. Data were analysed using two-way ANOVA. Results Significant differences existed in microhardness (P = 0.004) and percentage of remineralization (P < 0.001) after remineralization among the material groups such that the highest mean was noted in the CPP-ACP group. No significant difference was noted in microhardness (P = 0.052) or percentage of remineralization (P = 0.981) after remineralization among the laser groups. In all groups, porosities increased after demineralization and slightly decreased after remineralization; the greatest reduction in porosity of the material groups was noted in the fTCP group, and the CO2 group among the laser groups. The interaction effect of materials and lasers was not significant (P > 0.05). Conclusion The highest microhardness was achieved after remineralization with CPP-ACP. The efficacy of the diode and CO2 lasers was the same. No synergistic effect was found between materials and lasers. Trial registration This is not a human subject research.
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Affiliation(s)
- Elham Soltanimehr
- Department of Pediatric Dentistry, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Ehsan Bahrampour
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Kermanshah University of Medical Sciences, Building No. 1, Shahid Beheshti Boulevard, Kermanshah, 6715847141, Iran.
| | - Zeynab Yousefvand
- School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Chokhachi Zadeh Moghadam N, Seraj B, Chiniforush N, Ghadimi S. Effects of Laser and Fluoride on the Prevention of Enamel Demineralization: An In Vitro Study. J Lasers Med Sci 2019; 9:177-182. [PMID: 30809328 DOI: 10.15171/jlms.2018.32] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: Investigations have demonstrated that fluoride is an essential element in preventive dentistry. However, there are still controversies about the preventive effects of various kinds of laser. The aim of this study was to examine the effect of diode laser irradiation (810 nm) with or without fluoride therapy in the prevention of deciduous enamel demineralization. Methods: Sixty deciduous molar crowns were randomly assigned to 6 groups: C: received no treatment; F: fluoride varnish application; 2L: 2 times diode laser irradiation; 4L: 4 times diode laser irradiation; F2L: 2 times laser irradiation over fluoride varnish; F4L: 4 times laser irradiation over fluoride varnish. Teeth in all groups were subjected to a pH-cycling process to produce artificial caries-like lesions. Results: The analysis of variance (ANOVA) of microhardness values indicated a significant great effect for laser, fluoride, and the interaction of laser- fluoride on reducing the final microhardness value (P<0.001). However, the 2L group was an exception. Despite the 4L group, it did not show a significant prevention of enamel microhardness loss (P=0.125). These 2 groups exhibited different effects in the absence of fluoride (P 2L-4L=0.05) while in the presence of the fluoride varnish, no statistically significant difference was observed between them (P F2L-F4L=0.257). Moreover, no statistically significant difference was observed between the laser-fluoride combination group and the fluoride group (P F2L-F=0.133, P F4L-F=0.926). Conclusion: Our results suggest that fluoride varnish, diode laser, and their combination decrease the loss of the enamel microhardness value and potentially prevent deciduous enamel demineralization. However, the combination of laser and fluoride was not more effective than fluoride.
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Affiliation(s)
| | - Bahman Seraj
- Dental Research Center, Dentistry Research Institute and Department of Pediatric Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Nasim Chiniforush
- Laser Research Center of Dentistry, Dentistry research Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Sara Ghadimi
- Laser Research Center of Dentistry, Dentistry Research Institute and Department of Pediatric Dentistry, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
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Nogueira RD, Silva CB, Lepri CP, Palma-Dibb RG, Geraldo-Martins VR. Evaluation of Surface Roughness and Bacterial Adhesion on Tooth Enamel Irradiated With High Intensity Lasers. Braz Dent J 2018; 28:24-29. [PMID: 28301014 DOI: 10.1590/0103-6440201701190] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 11/01/2016] [Indexed: 11/21/2022] Open
Abstract
The aim was to evaluate the surface roughness and bacterial adhesion on enamel irradiated with high intensity lasers, associated or not to a fluoride varnish. Eighty fragments of bovine enamel were equally divided in 8 groups (n=10). Group 1 was not treated and Group 2 received only a 5% fluoride varnish application. The other groups were irradiated with an Er:Cr:YSGG (8.92 J/cm2), an Nd:YAG (84.9 J/cm2) and a diode laser (199.04 J/cm2), associated or not to a 5% fluoride varnish. The surface roughness was measured before and after treatments. Afterward, all samples were incubated in a suspension of S. mutans at 37 °C for 24 h. The colony-forming units (CFU) were counted by a stereoscope and the results were expressed in CFU/mm2. One-way ANOVA and the Tukey´s test compared the roughness data and the Student´s test compared the results obtained in the bacterial adhesion test (a=5%). The results showed that the irradiated samples without varnish presented the same roughness and the same bacterial adhesion that the non-irradiated samples. However, samples irradiated in the presence of fluoride varnish showed higher surface roughness and higher bacterial adhesion than the non-irradiated samples and those irradiated without varnish. Presence of pigments in the varnish increased the lasers' action on the enamel surface, which produced ablation in this hard tissue and significantly increased its surface roughness. For this reason, the enamel's susceptibility to bacterial adhesion was higher when the irradiation of the samples was made in presence of fluoride varnish.
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Affiliation(s)
- Ruchele D Nogueira
- Biopathology Division, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Camilla B Silva
- Biopathology Division, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Cesar P Lepri
- Clinical Dentistry, Dental School, UNIUBE - Universidade de Uberaba, Uberaba, MG, Brazil
| | - Regina Guenka Palma-Dibb
- Department of Restorative Dentistry, Ribeirão Preto Dental School, USP - Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Mirhashemi AH, Hakimi S, Ahmad Akhoundi MS, Chiniforush N. Prevention of Enamel Adjacent to Bracket Demineralization Following Carbon Dioxide Laser Radiation and Titanium Tetra Fluoride Solution Treatment: An In Vitro Study. J Lasers Med Sci 2017; 7:192-196. [PMID: 28144441 DOI: 10.15171/jlms.2016.33] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction: The aim of this study was to assess the caries-preventive potential of carbon dioxide (CO2) laser application in conjunction with the use of titanium tetra fluoride solution on the enamel adjacent to bracket. Methods: Seventy-five freshly extracted bovine incisors were used. In order to attach the brackets, the area of examination was covered with adhesive tape to limit acid etching of the entire enamel surface. Metal orthodontic brackets for upper central were bonded to all the teeth following the manufacturer's instruction. Then all the teeth were painted with 2 layers of acid-resistant nail varnish on all surfaces except the boxes area cervical to the brackets. The teeth were then randomly divided into five groups (n = 15): control group (C); laser group (L); titanium group (T); laser-titanium group (LT) and titanium-laser group (TL). The laser-titanium group was first irradiated with CO2 laser (same as the L group) then TiF4 solution was applied on the enamel (same as the T group). Samples in the TL group were first treated with TiF4 solution (same as the T group) and then irradiated with CO2 laser on the surface (same as the L group). Then, the teeth were immersed in pH-cycling solutions. After that, the amount of calcium released into the two solutions (de- and re-mineralization) was measured with an atomic absorption spectroscopy. The data were analyzed by one-way Analysis of var-iance (ANOVA) and Tukey test. Results: Calcium loss in LT, TL and T groups were significantly lower than those in the L and C groups (P < 0.05). Conclusion: The application of Titanium tetra fluoride 4% solution on enamel can inhibit as much as 87% of subsequent caries like lesion progression.
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Affiliation(s)
- Amir Hossein Mirhashemi
- Dental Research Center, Dentistry Research Institute, Department of Orthodontics, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mohammad Sadegh Ahmad Akhoundi
- Dental Research Center, Dentistry Research Institute, Department of Orthodontics, Tehran University of Medical Sciences, Tehran, Iran
| | - Nasim Chiniforush
- Laser Research Center of Dentistry, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran
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Raucci Neto W, Lepri CP, Faraoni Romano JJ, Fernandes FS, de Castro Raucci LMS, Bachmann L, Dibb RGP. Chemical and Morphological Changes of Primary Teeth Irradiated with Nd:YAG Laser: An Ex Vivo Long-Term Analysis. Photomed Laser Surg 2016; 33:266-73. [PMID: 25954828 DOI: 10.1089/pho.2014.3876] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE The aim of this study was to assess any long-term chemical and morphological Nd:YAG laser modifications on irradiated primary enamel. BACKGROUND DATA Previous studies on irradiated primary human enamel employed methodologies that evaluated the short-term effects only. METHODS One hundred and eighty-six irradiated (with and/or without fluoride) primary enamel teeth from high-caries-risk children, which were exfoliated over a 1-year period, were collected, and the sample surface area was submitted for scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray energy-dispersive spectrometry (EDS). The subsurface was analyzed by Knoop microhardness and light microscopy (LM). Data were analyzed by one way ANOVA and Tukey tests (α=0.05) and Kruskall-Wallis and Tukey tests (α=0.05). RESULTS FTIR analysis revealed a higher concentration of phosphate and carbonate in the irradiated (0.987±0.064) and lower concentration in the control groups (1.477±0.310). SEM analysis showed that the control samples exhibited a slightly smoother surface than the irradiated groups. The EDS analysis did not show any differences in the amount of calcium, phosphorus, or fluoride among the groups. The microhardness analysis revealed that sealant (249.86±7.15) and laser irradiation (262.44±22.69) led to higher hardness values than the negative control group (128.35±25.19). LM indicated significantly reduced caries formation in the laser (5.35±5.38%) and the laser plus acidulated phosphate fluoride (APF) groups (10.35±0.88%) compared with the negative control group (72.56±12.86%). CONCLUSIONS Even with the limitations of the present study, these results suggest that Nd:YAG irradiation clinically modified the chemical composition of the enamel surface regardless of fluoride concentration, which successfully inhibited demineralization of primary tooth enamel over a 1-year period without significant morphological changes.
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Affiliation(s)
- Walter Raucci Neto
- 1 Dentistry Department, University of Ribeirão Preto - UNAERP, Ribeirão Preto - SP, Brazil
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Zancopé BR, Rodrigues LP, Parisotto TM, Steiner-Oliveira C, Rodrigues LKA, Nobre-dos-Santos M. CO2 laser irradiation enhances CaF2 formation and inhibits lesion progression on demineralized dental enamel—in vitro study. Lasers Med Sci 2016; 31:539-47. [DOI: 10.1007/s10103-016-1900-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 02/02/2016] [Indexed: 11/28/2022]
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Chand BR, Kulkarni S, Mishra P. Inhibition of enamel demineralisation using "Nd-YAG and diode laser assisted fluoride therapy". Eur Arch Paediatr Dent 2015; 17:59-64. [PMID: 26474878 DOI: 10.1007/s40368-015-0206-8] [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] [Received: 06/15/2015] [Accepted: 09/04/2015] [Indexed: 11/28/2022]
Abstract
AIM This in vitro study was to evaluate the irradiation efficacy of the Diode laser and the Nd-YAG laser either un-assisted or assisted by acidulated phosphate fluoride (APF) treatment on enamel's acid resistance. METHODS Seventy-two enamel samples, obtained from 12 extracted human molars, were randomly assigned to 6 groups as follows: (1) Control (C); (2) Exposed to APF gel (F); (3) Diode laser (DL); (4) Irradiated with Diode laser through APF gel (DL/F); (5) Nd-YAG laser (NL) and (6) Irradiated with Nd-YAG laser through APF gel (NL/F). The specimens were individually demineralised in an acidified hydroxyethylcellulose system, and the acid resistance was evaluated by determining the calcium ion dissolution using atomic absorption spectrometry. RESULTS The average concentration of the calcium ion determined in groups 1 to 6 was 901, 757, 736, 592, 497 and 416 parts per million micrograms/gram, respectively. The results showed that demineralisation in the NL/F group was significantly less than the other groups and the control group was significantly greater than the other groups (P < 0.001). CONCLUSION The effect of Nd-YAG laser irradiation, used alone or in combination with APF, in decreasing the enamel demineralisation was greater than all the other groups.
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Affiliation(s)
- B R Chand
- Department of Pedodontics and Preventive Dentistry, Sri Aurobindo College of Dentistry, Indore, India.
| | - S Kulkarni
- Department of Pedodontics and Preventive Dentistry, Sri Aurobindo College of Dentistry, Indore, India.
| | - P Mishra
- Department of Public Health Dentistry, Sri Aurobindo College of Dentistry, Indore, India.
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Souza-Gabriel AE, Turssi CP, Colucci V, Tenuta LMA, Serra MC, Corona SAM. In situ study of the anticariogenic potential of fluoride varnish combined with CO2 laser on enamel. Arch Oral Biol 2015; 60:804-10. [PMID: 25791325 DOI: 10.1016/j.archoralbio.2015.01.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 12/12/2014] [Accepted: 01/31/2015] [Indexed: 10/24/2022]
Abstract
OBJECTIVE This in situ study evaluated the effect of fluoride varnish combined with CO2 laser in controlling enamel demineralization caused by cariogenic challenges. DESIGN In a crossover study conducted in 2 phases of 14 days each, 14 volunteers (n = 14) wore palatal appliances with bovine enamel slabs treated with fluoride varnish + CO2 laser (FV + CO2), fluoride varnish (FV), nonfluoride placebo varnish (PV) and nonfluoride placebo varnish + CO2 laser (PV + CO2). Drops of sucrose solution were dripped onto enamel slabs allowing the accumulation of biofilm. At the first phase, half of the volunteers received 4 enamel slabs treated with FV while the remainders received slabs exposed to the PV with and without CO2 laser. In the second phase, the vonlunteers were reversed treatments. The slabs were evaluated for cross-sectional microhardness (CSMH) and the concentration of loosely bound fluoride (CaF2) and firmly bound fluoride (FAp). The concentration of fluoride in biofilm were also determined. RESULTS Two-way ANOVA showed that the CSMH values were higher in laser-irradiated enamel, regardless of the fluoride varnish. Friedman test showed that FV group presented significantly larger amount of fluoride in biofilm (P < 0.05). In the enamel, the largest amount of fluoride was found in the groups FV + CO2, which was not different from FV (P > 0.05). CONCLUSION The synergistic effect of fluoride varnish and CO2 laser on enamel demineralization was not observed, however, CO2 laser reduces enamel demineralization. CLINICAL SIGNIFICANCE CO2 laser might reduce the demineralization of subsurface enamel, although its association with a high concentrated fluoride therapy may not result in a positive synergistic interaction.
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Affiliation(s)
- Aline Evangelista Souza-Gabriel
- Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
| | | | - Vivian Colucci
- Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Lívia Maria Andaló Tenuta
- Department of Physiological Sciences, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil
| | - Mônica Campos Serra
- Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Silmara Aparecida Milori Corona
- Department of Restorative Dentistry, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
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Miresmaeili A, Farhadian N, Rezaei-soufi L, Saharkhizan M, Veisi M. Effect of carbon dioxide laser irradiation on enamel surface microhardness around orthodontic brackets. Am J Orthod Dentofacial Orthop 2014; 146:161-5. [PMID: 25085298 DOI: 10.1016/j.ajodo.2014.04.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 04/01/2014] [Accepted: 04/01/2014] [Indexed: 11/26/2022]
Abstract
INTRODUCTION In this study, we aimed to determine the effect of carbon dioxide laser irradiation on enamel surface microhardness. METHODS In this single-blind interventional clinical trial, 16 patients needing at least 2 premolars extracted for orthodontic purposes participated. In each subject, 1 premolar was treated with the carbon dioxide laser (beam diameter, 0.2 mm; power, 0.7 W); the other was exposed to a visible guiding light as the control. A t-loop was ligated to the bonded brackets to increase caries risk. After at least 2 months, the teeth were extracted, and the surface microhardness was measured. Scanning electron microscope evaluation was performed on 1 sample from each group. Normal distribution of the data was assessed by the Kolmogorov-Smirnov and Shapiro-Wilks tests. Mean microhardness values of the 2 groups were compared using paired t tests. RESULTS The data had normal distributions. Means and standard deviations of the microhardness in the laser-treated and control groups were 301.81 ± 94.29 and 183.9 ± 72.08 Vickers hardness numbers, respectively; this was different significantly (P <0.001). Scanning electron microscopy showed the enamel surface melting in the laser-treated specimens. CONCLUSIONS Carbon dioxide laser treatment results in higher enamel surface microhardness around orthodontic brackets. Patients at high risk of caries might benefit from this intervention. Exact control of the laser irradiation parameters is recommended.
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Affiliation(s)
- Amirfarhang Miresmaeili
- Associate professor, Department of Orthodontics, Dental Research Center, Dental Faculty, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Nasrin Farhadian
- Associate professor, Department of Orthodontics, Dental Research Center, Dental Faculty, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Loghman Rezaei-soufi
- Associate professor, Department of Operative Dentistry, Dental Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
| | - Mehdi Saharkhizan
- Clinical instructor, Department of Pediatric Dentistry, Dental Faculty, Hamadan University of Medical Sciences, Hamadan, Iran
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Stangler LP, Romano FL, Shirozaki MU, Galo R, Afonso AMC, Borsatto MC, Matsumoto MAN. Microhardness of enamel adjacent to orthodontic brackets after CO2 laser irradiation and fluoride application. Braz Dent J 2014; 24:508-12. [PMID: 24474294 DOI: 10.1590/0103-6440201302292] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 09/03/2013] [Indexed: 11/22/2022] Open
Abstract
This study evaluated the effectiveness of carbon dioxide (CO2) laser combined or not with fluoride application on the surface microhardness of enamel adjacent to orthodontic brackets. Fifteen human molars were selected from which 30 enamel fragments measuring 4 mm2 were obtained. The fragments were embedded in PCV tubes with acrylic resin and prepared using water abrasive paper, felt disks and alumina. Orthodontic brackets cut in half were bonded to enamel and 3 microhardness readings were performed on the adjacent surface, as follows: initial, after cariogenic challenge and final. The specimens were divided into the following 3 groups (n=10): Group C: control, Group L: irradiated with CO2 laser, and Group FL: topical fluoride application and CO2 laser irradiation. After initial reading, the specimens were placed in a demineralizing solution for 32 h and the second reading was to verify if demineralization was uniform in all groups. After the treatments, the specimens were submitted to DES-RE cycling for 8 days followed by final surface microhardness reading. The data were analyzed statistically using ANOVA and Duncan test (α=0.05). At the final measurement Group FL obtained higher microhardness value than Groups C and L (p<0.05). Groups L and FL were statistically superior to Group C (p<0.05). Irradiation with CO2 laser around orthodontic brackets combined or not with topical fluoride application was effective to increase the surface microhardness of enamel.
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Affiliation(s)
- Leonardo Pucci Stangler
- Department of Pediatric Clinic, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
| | - Fábio Lourenço Romano
- Department of Pediatric Clinic, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
| | - Mariana Umekita Shirozaki
- Department of Pediatric Clinic, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
| | - Rodrigo Galo
- Department of Dental Materials, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
| | | | - Maria Cristina Borsatto
- Department of Pediatric Clinic, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
| | - Mírian Aiko Nakane Matsumoto
- Department of Pediatric Clinic, Ribeirão Preto School of Dentistry, USP - University of São Paulo, Ribeirão PretoSP, Brazil
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Raucci-Neto W, de Castro-Raucci LMS, Lepri CP, Faraoni-Romano JJ, Gomes da Silva JM, Palma-Dibb RG. Nd:YAG laser in occlusal caries prevention of primary teeth: a randomized clinical trial. Lasers Med Sci 2013; 30:761-8. [PMID: 23955196 DOI: 10.1007/s10103-013-1417-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/29/2013] [Indexed: 10/26/2022]
Abstract
Dental caries is still the most prevalent chronic disease affecting human populations. Among the preventive treatments performed, it has been reported that laser irradiation combined with topical fluoride can induce an even greater increase in enamel caries resistance. The aim of this study was to evaluate the Nd:YAG laser, with or without fluoride, in occlusal caries prevention of the primary dentition. A double-blind split-mouth study design was used. Fifty-two children with high caries risk (7.6 ± 1.4 years) were selected and received the following: G1--the first molar was a negative control, and the second received a resin sealant; G2--the first molar was a negative control, and the second received laser irradiation (50 mJ, 10 Hz, 0.5 W); G3--the first molar received only acidulate phosphate fluoride (APF), and the second received APF + laser; G4--fisrt molar received only fluoride varnish, and the second received fluoride varnish + laser. Patients were followed up to 12 months to evaluate the presence of white-spot lesions and/or caries cavities by three calibrated observers. Thirty-five patients completed the study. Significant differences were found between the treatment and control groups (p < 0.05). The laser-alone and resin sealant resulted in statistically lower caries formation than the negative control group (p < 0.05). Nd:YAG laser irradiation in primary teeth effectively prevented occlusal caries in pits and fissures when used alone with lower energy over a 1-year period.
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Affiliation(s)
- Walter Raucci-Neto
- Department of Restorative Dentistry, Ribeirão Preto Dental School, University of São Paulo, Avenida do Café, s/nº, Monte Alegre, CEP 14040-904, Ribeirão Preto, SP, Brazil,
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Sabaeian M, Shahzadeh M. Simulation of temperature and thermally induced stress of human tooth under CO2 pulsed laser beams using finite element method. Lasers Med Sci 2013; 30:645-51. [PMID: 23868367 DOI: 10.1007/s10103-013-1390-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 07/08/2013] [Indexed: 12/13/2022]
Abstract
The authors report the simulation of temperature distribution and thermally induced stresses of human tooth under CO2 pulsed laser beam. A detailed tooth structure comprising enamel, dentin, and pulp with realistic shapes and thicknesses were considered, and a numerical method of finite element was adopted to solve time-dependent bio-heat and stress equations. The realistic boundary conditions of constant temperature for those parts embedded in the gingiva and heat flux condition for those parts out of the gingiva were applied. The results which were achieved as a function of energy density (J/cm(2)) showed when laser beam is irradiated downward (from the top of the tooth), the temperature and thermal stresses decrease quickly as a function of depth that is a result of strong absorption of CO2 beams by enamel. This effect is so influential that one can use CO2 beams to remove micrometer layers while underlying tissues, especially the pulp, are safe from thermal effects.
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Affiliation(s)
- Mohammad Sabaeian
- Physics Department, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran,
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29
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Evaluation of acquired acid resistance of enamel surrounding orthodontic brackets irradiated by laser and fluoride application. Lasers Med Sci 2013; 29:1793-8. [DOI: 10.1007/s10103-013-1328-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 04/15/2013] [Indexed: 11/26/2022]
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Poosti M, Ahrari F, Moosavi H, Najjaran H. The effect of fractional CO2 laser irradiation on remineralization of enamel white spot lesions. Lasers Med Sci 2013; 29:1349-55. [PMID: 23519913 DOI: 10.1007/s10103-013-1290-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 02/18/2013] [Indexed: 10/27/2022]
Abstract
This study investigated the combined effect of fractional CO(2) laser irradiation and fluoride on treatment of enamel caries. Sixty intact premolars were randomly assigned into four groups and then stored in a demineralizing solution to induce white spot lesions. Tooth color was determined at baseline (T1) and after demineralization (T2). Afterwards, the teeth in group 1 remained untreated (control), while group 2 was exposed to an acidulated phosphate fluoride (APF) gel for 4 min. In groups 3 and 4, a fractional CO(2) laser was applied (10 mJ, 200 Hz, 10 s) either before (group 3) or through (group 4) the APF gel. The teeth were then immersed in artificial saliva for 90 days while subjected to daily fluoride mouthrinse and weekly brushing. Color examinations were repeated after topical fluoride application (T3) and 90 days later (T4). Finally, the teeth were sectioned, and microhardness was measured at the enamel surface and at 30 and 60 μ from the surface. In both lased groups, the color change between T1 and T4 stages (∆E(T1-T4)) was significantly lower than those of the other groups (p < 0.05). Laser irradiation followed by fluoride application (group 3) caused a significant increase in surface microhardness compared to APF alone and control groups (p < 0.05). Microhardness at depths of 30 and 60 μ was also significantly greater in group 3 compared to those of all other groups (p < 0.05). Application of a fractional CO(2) laser before fluoride therapy is suggested for recovering the color and rehardening of demineralized enamel.
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Affiliation(s)
- Maryam Poosti
- Department of Orthodontics, School of Dentistry, Islamic Azad University, Tehran, Iran
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