Microbiological Efficacy of Photodynamic Therapy as an Adjunct to Non-surgical Periodontal Treatment: A Clinical Trial

Introduction: The efficiency of routine scaling and root planning is negatively influenced by the tooth anatomy and residual bacteria all possibly affecting the treatment outcomes in future. The present study compared the microbiologic effectiveness of the photodynamic therapy (PDT) as an adjunctive treatment modality for nonsurgical treatment in chronic periodontitis.Methods: In this randomized controlled clinical trial, 18 chronic periodontitis patients were selected. Four quadrants were randomly treated by scaling and root planning (SRP), diode laser (810n m wavelength, 1.5 W and 320 μm fiber, contact and sweeping technique), SRP + PDT (with diode laser 808 nm, 0.5 W) and laser + SRP (with diode laser 808 nm, 1 W) in each patient. Presence of periodontal pathogen species in the treated areas were measured before the treatment, at 1 and 3 months afterwards. The identification and reproduction of the specific genes of pathogen bacteria were done by means of polymerase chain reaction (PCR) technique. Presence of oral pathogen bacteria in the treatment groups were analyzed by chi-square test. A semi quantitative analysis was used to measure the intensity of white light in each band. This was calculated by number of pixels in each band.Results: In the qualitative analysis, Fusobacterium nucleatum (Fn) and Treponema denticola (Td) species were killed after 1 month in all treatment modalities. PDT had more effects to decrease Prevotella intermedia (Pi) species than SRP while Tannerella forsythensis count (Tf) species increased in all treatments. Furthermore, Actinobacillus actinomycetemcomitans (Aa) species decreased in all treatments and Porphyromonas gingivalis (P.g) species increased in all treatments after 1 and 3 months.Conclusion: It can be concluded that PDT was more effective as an adjunctive treatment to SRP than SRP alone; however, no distinct differences were found between both treatment modalities regarding reduction of certain pathogen bacteria

Laser Assisted Treatment of Extra Oral Cutaneous Sinus Tract of Endodontic Origin: A Case Report

Introduction: Sinus tracts (or fistulas) are a common manifestation of pulpal necrosis that requires conventional or rarely surgical- endodontic treatment in order to heal. They are mainly identified intraorally and in rare cases they manifest extraorally which may frequently be misdiagnosed and incorrectly treated. New technologies such as lasers have been developed as adjuncts to standard endodontic antimicrobial procedures in order to increase the success rate of endodontic therapy and complying the desire of saving a natural tooth.Case presentation: Herein, we present a clinical case of extra oral sinus tract with Periodic pus drainage that was successfully treated by combining   conventional endodontic therapy, intra canal PDT and extra oral low level laser therapy.Results and conclusion: Treatment of the odontogenic lesion among with the extra oral lesion was an ingenious and successful technique which was achieved by laser technology and winded up to patient’s consent and satisfactory results of treatment

Effect of Diode Laser (810 nm) Irradiation on Marginal Microleakage of Multi-mode Adhesive Resins in Class V Composite Restorations

Introduction: Some studies have shown that laser irradiation on unpolymerized adhesives can improve composite-dentin adhesion. The aim of the present study was to evaluate the effect of the Diode laser (810 nm) on the microleakage of multi-mode adhesive systems at enamel and dentin margins of composite restorations.Methods: Classic Class V boxes were prepared on 48 sound premolar teeth and randomly divided into six groups (n=16). In the control groups, Scotch bond U(SBC), G-Premio (GBC), and Ambar U (AMC) were used by a self-etch mode. In the test groups (SBL, GBL, ABL), the 810 nm Diode laser was irradiated (1 Watt) for 10 seconds before the polymerization of the adhesive. The Boxes were restored by the resin composite. After finishing and polishing, the samples were thermocycled (5℃ to55℃) for 1000 cycles and then immersed in 0.1% Methylene blue dye (48 hours). Dye penetration through the gingival and occlusal margins was measured by Stereomicroscope. The data were analyzed at the 5% significance level using Kruskal-Wallis and Mann-Whitney U tests.Results: Significant differences were found between the control and test groups (p<0.05). The occlusal margins of the SBL and GBL groups and the cervical margin of the SBL group exhibited the lowest microleakage (p<0.05). The AM control group showed maximum microleakage at cervical and occlusal margins.Conclusions: The irradiation of the 810 nm Diode laser on the unpolymerized universal adhesive systems in a self-etch mode caused a significant reduction in enamel and dentin marginal microleakage of composite restorations.

Effect of Er:YAG Laser Irradiation Combined With Fluoride Application on the Resistance of Primary and Permanent Dental Enamel to Erosion

Introduction: Erosion is an important cause of tooth mineral loss. The combined use of lasers and fluoride has been introduced as a novel modality for the prevention of enamel demineralization. This study aimed to assess the effect of Er:YAG laser combined with fluoride application on primary and permanent enamel resistance to erosion.Methods: Eighty enamel specimens of permanent (n=40) and primary (n=40) molars were prepared and randomly assigned to four groups:  C —control (no pretreatment), F—acidulated phosphate fluoride (APF) gel, ­­­­­FL—APF gel application followed by Er:YAG laser irradiation, and LF—Er:YAG laser irradiation followed by the application of APF gel . The specimens were then submitted to pH cycling using Coca-Cola (pH=2.4). Enamel micro-hardness was measured using the Vickers micro-hardness tester before pretreatment and after the erosive process. The collected data were analyzed using the Kolmogorov-Smirnov test, two-way ANOVA and repeated measures ANOVA.Results: The micro-hardness of both permanent and primary enamel significantly decreased after the erosive process (P<0.05). In the permanent enamel specimens, the greatest reduction in micro-hardness was noted in groups C and F, while the least reduction was noted in group FL. However, these differences were not statistically significant (P>0.05). In the primary enamel specimens, the greatest reduction in micro-hardness was noted in groups C and LF, while the least reduction was noted in group F. These differences were not statistically significant (P>0.05).Conclusion: Within the limitations of this study, Er:YAG laser irradiation combined with fluoride application could not prevent erosion in permanent and primary enamel during the erosive process. 

Effects of Root Debridement With Hand Curettes and Er:YAG Laser on Chemical Properties and Ultrastructure of Periodontally-Diseased Root Surfaces Using Spectroscopy and Scanning Electron Microscopy

Introduction: The efficacy of erbium-doped yttrium aluminum garnet (Er:YAG) laser for root debridement in comparison with curettes has been the subject of many recent investigations. Considering the possibility of chemical and ultra-structural changes in root surfaces following laser irradiation, this study sought to assess the effects of scaling and root planing (SRP) with curettes and Er:YAG laser on chemical properties and ultrastructure of root surfaces using spectroscopy and scanning electron microscopy (SEM).Methods: In this in vitro experimental study, extracted sound human single-rooted teeth (n = 50) were randomly scaled using manual curettes alone or in conjunction with Er:YAG laser at 100 and 150 mJ/pulse output energies. The weight percentages of carbon, oxygen, phosphorous and calcium remaining on the root surfaces were calculated using spectroscopy and the surface morphology of specimens was assessed under SEM. Data were analyzed using one-way analysis of variance (ANOVA).Results: No significant differences (P > 0.05) were noted in the mean carbon, oxygen, phosphorous and calcium weight percentages on root surfaces following SRP using manual curettes with and without laser irradiation at both output energies. Laser irradiation after SRP with curettes yielded rougher surfaces compared to the use of curettes alone.Conclusion: Although laser irradiation yielded rougher surfaces, root surfaces were not significantly different in terms of chemical composition following SRP using manual curettes with and without Er:YAG laser irradiation. Er:YAG laser can be safely used as an adjunct to curettes for SRP

Management of Post Endodontic Retreatment Pain With Low Level Laser Therapy

Introduction: Pharmacotherapy with analgesics and non-steroidal anti-inflammatory drugs has been traditionally used to relief post-operative pain of endodontic treatments. However, due to the side effects reported for these drugs, some efforts have been made to decrease the post-operative pain of the endodontic treatments through laser irradiation. The present study aimed to evaluate the effects of low level laser therapy (LLLT) on the reduction of pain after root canal retreatment.Methods: In this clinical trial, 61 patients requiring endodontic retreatments in posterior teeth were selected. A single visit endodontic retreatment was performed. After biomechanical preparation, low level laser was irradiated to the buccal and lingual mucosa overlying the apices of the target tooth in the experimental group. In the control group patients received placebo laser to eliminate the probable psychological effects of laser. Laser irradiation was done with a single dose of 808 nm wavelength (Whitening Lase II- Laser DMC, Samsung, Korea) with 100 mW power, and dose of 70 J/cm2 for 80 seconds. Pain severity was recorded before, immediately after and 4, 8, 12, 24 and 48 hours after the treatment by visual analogue scale (VAS). The pain scores were statistically analyzed by chi-square test between 2 groups. The effects of different variables on the post-operative pain experience were also studied by means of Logistic regression.Results: Pain scores decreased significantly through time until 48 hours after treatment. No significant differences were observed between the 2 modalities regarding pain scores at any time. According to regression analysis, pain severity scores were lower in the laser-irradiated specimens than control groups (OR = 5.69); however, this difference was not statistically significant. Consumption of analgesics after the treatment had significant effect in decreasing post-operative pain experience (OR = 56) while factors of age, gender, laser irradiation, pre-treatment pain scores and education level did not.Conclusion: Low level laser irradiation had limited effects to decrease pain associated with the endodontic retreatments in the first and second molars; however, more studies are required to assess the effects of different parameters of low level laser in this regard

Low Level Laser Therapy Versus Pharmacotherapy in Improving Myofascial Pain Disorder Syndrome

Introduction: Temporomandibular disorders (TMD) lead to masticatory muscle pain, jaw movement disability and limitation in mouth opening. Pain is the chief complaint in 90% of the TMD patients which leads to disability and severe socioeconomic costs. The purpose of this study was to evaluate the therapeutic effects of low level laser therapy (LLLT) compared to pharmacotherapy with NSAIDs (naproxen) in myofascial pain disorder syndrome (MPDS).Methods: In this randomized controlled clinical trial, 40 MPDS patients were divided into two groups. One group received naproxen 500 mg bid for 3 weeks as treatment modality and also had placebo laser sessions. The other group received active laser (diode 810 nm CW) as treatment and placebo drug. Pain intensity was measured by visual analogue scale (VAS) and maximum painless mouth opening was also measured as a functional index every session and at 2 months follow up. Data was collected and analyzed with SPSS software. Independent t test was used to analyze the data. A P < 0.05 was considered significant.Results: Low level laser caused significant reduction in pain intensity (P < 0.05) and a significant increase in mouth opening. In naproxen group neither pain intensity nor maximum mouth opening had significant improvement. Pain relief, in subjective VAS was observed in third session in LLLT group, but did not occur in naproxen group. Maximum mouth opening increased significantly in laser group compared to the naproxen group from the eighth session.Conclusion: Treatment with LLLT caused a significant improvement in mouth opening and pain intensity in patients with MPDS. Similar improvement was not observed in naproxen group

The Clinical Evaluation of the Effects of Low-Level Laser Therapy on the Donor and Recipient Sites of the Free Gingival Graft: A Case Series

Introduction: Free gingival grafting is among the most foreseeing procedures for increasing the zone of keratinized attached gingiva and enhancing soft tissue around the teeth and dental implants. Nowadays low-level laser therapy (LLLT) is a promising approach in providing patients with more pleasing results in terms of esthetics and comfort. This study aims to investigate the effects of LLLT on gingival recessions treated with free gingival graft (FGG).Methods: This case series was conducted on 12 individuals requiring a bilateral gingival graft in the mandibular region. There was a 30-day interval between the two operations. The test side was selected randomly and irradiated by a low-level laser (LLL) just before surgery. The patients did not know which side was irradiated. LLLT was applied to the donors’ as well as recipients’ site immediately after the operation and 48 hours later. The patients were instructed to record their post-operative pain in a visual analogue scale (VAS) 3 and 24 hours and 7 days after the surgical procedure. The clinical photographs were taken immediately and 30 days after surgical treatment were graded by three experienced periodontists for color matching to adjacent tissues.Results: Ten individuals could finish the study. The test group presented significantly better shade matching and wound healing at the palatal donor site on days 7, 14 and 21. There was a significant reduction in postoperative pain after 24 hours (P = 0.007). No statistically significant difference was found between both groups in terms of clinical periodontal indices.Conclusion: LLLT could reduce post-operative pain 24 hours after surgical treatment. Furthermore, the application of LLLT could improve the donors’ site healing and the recipients’ site color matching

Comparison of Er:YAG Laser and Hand Instrumentation on the Attachment of Cultured Human Gingival Fibroblasts to Periodontally Involved Root Surfaces

BackgroundThe present study compared the effects of Er:YAG laser and hand instrumentation on the attachment of human gingival fibroblast (HGF) cells to periodontally involved root surfaces.MethodsA total of 40 tooth specimens were collected and treated in four distinct groups: scaled and root planed with hand instruments, treated with Er:YAG laser, treated with combination of hand instruments and Er:YAG laser and non-treated control group. The attachment and proliferation rate of HGF were assessed using MTT assay and the Scanning Electron Microscope (SEM) Examination was used for cell morphological evaluation.ResultsThe MTT assay showed significantly decrease in HGF cell viability in both hand instruments only and combination treated teeth specimens compared to control specimens (p<0.05), 24 hours after cell seeding. However, at time 48, the cell viability of attached cells in these two treated groups was almost similar to control.  In contrast, at 24 and 48 hours after cell seeding, viability of attached cells was higher than control in Er:YAG laser treated only specimens (p<0.05). According to SEM study, the laser treated specimens showed more surface roughness.ConclusionsEr:YAG laser increased attachment and proliferation of HGF cells in comparison with hand instruments method

A Comparative Histological Study of Gingival Depigmentation by 808 and 445 nm Diode Lasers: Histological evaluation after gingival diode laser depigmentation

Introduction: Using lasers in melanin depigmentation is one of the main fields of interest for dental practitioners and patients. However, it is important to know what would happen inside the tissue and how the cells would interact inside the tissue with a laser.Methods: In this study, we used both wavelengths of 445 nm and 808 nm on sheep gingiva to find out the effects and side effects of these diode lasers while using them for gingival depigmentation.Results: After microscopic evaluation, we concluded that 808 nm and 445 nm lasers with a power of 1 W are safe enough to use in the depigmentation of gingiva, and both lasers are highly effective in melanin pigments which are located in the basal membrane.Conclusion: The 445 nm blue laser produced a less thermal effect, which means it is safer to be used in gingival hyperpigmentation than a diode lase