RESUMO
To evaluate the effect of Er:YAG laser conditioning of a glass-infiltrated alumina-based zirconia-reinforced ceramic on its flexural strength and on bonding to a resin cement. Sixteen blocks (5 × 5 × 4 mm) and 50 discs (Ø 12 mm, 1 mm thickness) of In-Ceram Zirconia (ICZ) obtained from CAD-CAM blocks were infiltrated with glass. For the microtensile bond strength (µTBS) test, all blocks were treated with aluminum oxide (AOX) and divided into 4 groups (n = 4): G1 (AOX), no combined surface treatment; G2 (ROC), tribochemical silica-coating; G3 (EY200), Er:YAG laser 200 mJ/15 Hz; and G4 (EY250), Er:YAG laser 250 mJ/10 Hz. The ceramic blocks were silanated and cemented with a resin cement (Panavia F2.0/Kuraray) to composite resin blocks and subjected to the µTBS test. For the flexural strength evaluation, the discs were divided into 5 groups (n = 10) as described above, in addition to a control group (G5 - CTRL, mirror-polished without further treatment). Each surface treatment was submitted to qualitative evaluation under SEM. One-way ANOVA (α = 5%) revealed the highest bond strength value for EY200 with no significant difference from ROC. The groups AOX and EY250 showed similar µTBS values that were statistically lower than those of EY200. For flexural strength, ROC was the only group with significantly lower values when compared with the CTRL. The use of Er:YAG laser at 200 mJ/15 Hz can be considered an innovative and effective alternative for surface conditioning of ICZ since it did not reduce the flexural strength of the ceramic and improved the resin cement bond to this substrate.
Assuntos
Colagem Dentária , Lasers de Estado Sólido , Cerâmica , Lasers de Estado Sólido/uso terapêutico , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , ZircônioRESUMO
The present study aims to evaluate the current scientific data regarding the effectiveness of photobiomodulation (PBM) in the treatment of dentin hypersensitivity (DH) as an alternative method for pain control. A systematic review was conducted to assess the effectiveness of PBM as treatment for DH. A complete literature search was performed up to October 2016. Searches were conducted using Boolean operators and MeSH terms. References of all selected full-text articles and related reviews were scanned. A total of 280 articles were identified (241 articles were excluded by the title and abstract). Of the 39 articles selected for analysis, 36 were excluded because they presented one or more exclusion criteria. Therefore, three articles were qualified for inclusion in this systematic review. PBM may not lead to adverse effects provided that adequately controlled parameters are followed when treating DH. More consistent studies should be conducted in order to adequately observe the advantageous therapeutic effect of PBM.
Assuntos
Sensibilidade da Dentina/radioterapia , Terapia com Luz de Baixa Intensidade/métodos , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
This randomized and longitudinal in vivo study aimed to assess different protocols for the treatment of dentin hypersensitivity with low-power laser (with different doses), high-power laser, and a desensitizing agent, for a period of 12 and 18 months. The lesions from 32 patients (117 lesions), who were submitted to the inclusion and exclusion criteria, were divided into nine groups (n = 13): G1: Gluma Desensitizer (Heraeus Kulzer), G2: low-power laser with low dose (three points of irradiation in vestibular portion and an apical point 30 mW, 10 J/cm2, 9 s per point with the wavelength of 810 nm, with three sessions with an interval of 72 h), G3: low-power laser with high dose (one point in the cervical area, and one apical point 100 mW, 40 J/cm2, 11 s per point with the wavelength of 810 nm in three sessions with an interval of 72 h), G4: low-power laser with low dose + Gluma Desensitizer, G5: low-power laser with high dose + Gluma Desensitizer, G6: Nd:YAG laser (Power Laser™ ST6, Research® in contact 1.0 W, 10 Hz and 100 mJ, ≈85 J/cm2, with the wavelength of 1064 nm), G7: Nd:YAG laser + Gluma Desensitizer, G8: low-power laser with low dose + Nd:YAG laser, and G9: low-power laser with high dose + Nd:YAG laser. The level of sensitivity of each volunteer was assessed by visual analog scale of pain (VAS) with the aid of air from the triple syringe and exploration probe, 12 and 18 months after treatment. All analyses were performed separately for air and probe stimulus. The level of significance was considered for values of p < 0.05. After statistical analysis, all treatments were shown to be effective in reducing dentinal hypersensitivity, and the results were considered not statistically different from those at 12 months. Therefore, until the 18-month evaluation, it could be said that no statistical differences were observed in the sensitivity levels for all treatments.
Assuntos
Sensibilidade da Dentina/terapia , Terapia com Luz de Baixa Intensidade , Adulto , Ar , Dentina/efeitos da radiação , Sensibilidade da Dentina/radioterapia , Glutaral/uso terapêutico , Humanos , Lasers de Estado Sólido , Estudos Longitudinais , Metacrilatos/uso terapêutico , Pessoa de Meia-Idade , Medição da Dor , Adulto JovemRESUMO
This randomized placebo-blind study aimed to evaluate the effect of laser phototherapy (LPT) on pain caused by symptomatic irreversible pulpitis (SIP). Sixty patients diagnosed with SIP were randomly assigned to treatment groups (n = 15): G1 (control), G2 (laser placebo-sham irradiation), G3 (laser irradiation at 780 nm, 40 mW, 4 J/cm2), and G4 (laser irradiation at 780 nm, 40 mW, 40 J/cm2). Spontaneous pain was recorded using a VAS score before (T0), immediately after (T1), and 15 min after treatment (T2). Local anesthetics failure during emergency endodontic treatment was also assessed. There was no pain difference in T1 and T2 between the experimental laser groups (G3 and G4) and the placebo group (G2). The 4-J/cm2 (G3) irradiation resulted in significant increase in the local anesthetics failure in lower jar teeth. This effect could be suggested as consequence of the LPT improvement in local circulation and vasodilatation that would result in the increase of local anesthetic agent absorption. The application of 780-nm diode laser irradiation, at 4 and 40 J/cm2, showed no effect in reducing the pain in SIP in comparison to the placebo group. The fluence of 4 J/cm2 showed a negative effect in local anesthetics, resulting in significant increase of complimentary local anesthesia during emergency endodontic treatment. This work provides evidence of the consequence of LPT application on teeth with symptomatic irreversible pulpitis. LPT should be avoided in teeth with pain due to irreversible pulpitis.
Assuntos
Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Dor/radioterapia , Pulpite/radioterapia , Adulto , Anestésicos Locais , Método Duplo-Cego , Feminino , Humanos , Lasers , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Pulpite/complicações , DenteRESUMO
Limited information is available regarding the adhesion to eroded dentin. This study aims to evaluate the effect of different surface treatments on eroded dentin morphology and on microtensile bond strength (µTBS) of adhesive systems to this substrate. Ninety-six extracted third molars were randomly divided into eight groups (n = 12) according to the type of surface treatment and the adhesive system: G1 = Control + Clearfil SE Bond [SE], G2 = Diamond bur [DB] + SE, G3 = Er:YAG laser (60 mJ, 2 Hz, 0.12 W, 19.3 J/ cm(2)) + SE, G4 = Er,Cr:YSGG laser (50 mJ, 30 Hz, 1.5 W, 4.5 J/ cm(2)) + SE, G5 = Control + Single Bond [SB], G6 = DB + SB, G7 = Er:YAG + SB, G8 = Er,Cr:YSGG + SB. The erosive cycling was performed by immersion in 0.05 M citric acid (pH 2.3, 10 min, 6x/day) and in supersaturated solution (pH 7.0, 1 h, between acid attacks), during 5 days. Blocks of composite were bonded to the samples according to the manufacturers' instructions. After 24 h-storage in distilled/deionized water (37 °C), stick-shaped samples were obtained and submitted to µTBS test. Each surface treatment was analyzed under scanning electron microscopy (n = 4) and the bond strength values (megapascal) were analyzed by two-way ANOVA and Tukey tests (α = 0.05). All surface treatments lead to changes on eroded dentin. G4 showed the highest bond strength mean (28.3 ± 9.2 MPa), which was statistically significant higher than all the other groups (p < 0.05). The surface treatment with Er,Cr:YSGG laser irradiation (4.5 J/cm(2)/50 mJ/30 Hz/140 µs) prior to bonding with a self-etching adhesive system significantly increases adhesion to eroded dentin, as compared to conventional treatment.
Assuntos
Cromo/química , Cimentos Dentários/farmacologia , Dentina/efeitos da radiação , Érbio/química , Lasers de Estado Sólido/uso terapêutico , Erosão Dentária/radioterapia , Colagem Dentária , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Adesivos Dentinários/farmacologia , Humanos , Resistência à Tração/efeitos dos fármacosRESUMO
Post-traumatic nerve repair represents a major challenge to health sciences. Although there have been great advances in the last few years, it is still necessary to find methods that can effectively enhance nerve regeneration. Laser therapy has been widely investigated as a potential method for nerve repair. Therefore, in this article, a review of the existing literature was undertaken with regard to the effects of low-power laser irradiation on the regeneration of traumatically/surgically injured nerves. The articles were selected using either electronic search engines or manual tracing of the references cited in key papers. In electronic searches, we used the key words as "paresthesia", "laser therapy", "low-power laser and nerve repair", and "laser therapy and nerve repair", considering case reports and clinical studies. According to the findings of the literature, laser therapy accelerates and improves the regeneration of the affected nerve tissues, but there are many conflicting results about laser therapy. This can be attributed to several variables such as wavelength, radiation dose, and type of radiation. All the early in vivo studies assessed in this research were effective in restoring sensitivity. Although these results indicate a potential benefit of the use of lasers on nerve repair, further double-blind controlled clinical trials should be conducted in order to standardize protocols for clinical application.
Assuntos
Terapia com Luz de Baixa Intensidade , Regeneração Nervosa/efeitos da radiação , Parestesia/radioterapia , Animais , Humanos , Parestesia/fisiopatologiaRESUMO
Oral mucositis (OM) is one of the side effects of hematopoietic stem cell transplantation (HSCT), resulting in major morbidity. The aim of this study was to determine the cost-effectiveness of the introduction of a specialized oral care program including laser therapy in the care of patients receiving HSCT with regard to morbidity associated with OM. Clinical information was gathered on 167 patients undergoing HSCT and divided according to the presence (n = 91) or absence (n = 76) of laser therapy and oral care. Cost analysis included daily hospital fees, parenteral nutrition (PN) and prescription of opioids. It was observed that the group without laser therapy (group II) showed a higher frequency of severe degrees of OM (relative risk = 16.8, 95% confidence interval -5.8 to 48.9, p < 0.001), with a significant association between this severity and the use of PN (p = 0.001), prescription of opioids (p < 0.001), pain in the oral cavity (p = 0.003) and fever > 37.8°C (p = 0.005). Hospitalization costs in this group were up to 30% higher. The introduction of oral care by a multidisciplinary staff including laser therapy helps reduce morbidity resulting from OM and, consequently, helps minimize hospitalization costs associated with HSCT, even considering therapy costs.
Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Terapia com Luz de Baixa Intensidade , Infecções Oportunistas/prevenção & controle , Higiene Bucal/métodos , Estomatite/terapia , Condicionamento Pré-Transplante/efeitos adversos , Adulto , Idoso , Aloenxertos/economia , Antibacterianos/administração & dosagem , Antibacterianos/economia , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/economia , Antifúngicos/administração & dosagem , Antifúngicos/economia , Antifúngicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Brasil , Estudos de Casos e Controles , Análise Custo-Benefício , Odontólogos/economia , Custos de Medicamentos , Feminino , Transplante de Células-Tronco Hematopoéticas/economia , Custos Hospitalares , Hospitalização/economia , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/economia , Imunossupressores/uso terapêutico , Terapia com Luz de Baixa Intensidade/economia , Terapia com Luz de Baixa Intensidade/métodos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/economia , Agonistas Mieloablativos/uso terapêutico , Entorpecentes/economia , Entorpecentes/uso terapêutico , Infecções Oportunistas/economia , Infecções Oportunistas/etiologia , Higiene Bucal/economia , Nutrição Parenteral/economia , Equipe de Assistência ao Paciente , Estudos Retrospectivos , Autocuidado/economia , Estomatite/economia , Estomatite/etiologia , Estomatite/prevenção & controle , Condicionamento Pré-Transplante/economia , Transplante Autólogo/economiaRESUMO
The aim of this in vitro study was to evaluate the effect of different surface treatments (control, diamond bur, erbium-doped yttrium aluminum garnet (Er:YAG) laser, and erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser) on sound dentin surface morphology and on microtensile bond strength (µTBS). Sixteen dentin fragments were randomly divided into four groups (n = 4), and different surface treatments were analyzed by scanning electron microscopy. Ninety-six third molars were randomly divided into eight groups (n = 12) according to type of surface treatment and adhesive system: G1 = Control + Clearfil SE Bond (SE); G2 = Control + Single Bond (SB); G3 = diamond bur (DB) + SE; G4 = DB + SB, G5 = Er:YAG laser (2.94 µm, 60 mJ, 2 Hz, 0.12 W, 19.3 J/cm(2)) + SE; G6 = Er:YAG + SB, G7 = Er,Cr:YSGG laser (2.78 µm, 50 mJ, 30 Hz, 1.5 W, 4.5 J/cm(2)) + SE; and G8 = Er,Cr:YSGG + SB. Composite blocks were bonded to the samples, and after 24-h storage in distilled/deionized water (37 °C), stick-shaped samples were obtained and submitted to µTBS test. Bond strength values (in megapascal) were analyzed by two-way ANOVA and Tukey tests (α = 0.05). G1 (54.69 ± 7.8 MPa) showed the highest mean, which was statistically significantly higher than all the other groups (p < 0.05). For all treatments, SE showed higher bond strength than SB, except only for Er,Cr:YSGG treatment, in which the systems did not differ statistically from each other. Based on the irradiation parameters considered in this study, it can be concluded that Er:YAG and Er,Cr:YSGG irradiation presented lower values than the control group; however, their association with self-etching adhesive does not have a significantly negative effect on sound dentin (µTBS values of >20 MPa).
Assuntos
Adesivos/farmacologia , Adesivos Dentinários , Dentina/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Resistência à Tração , Bis-Fenol A-Glicidil Metacrilato , Colagem Dentária , Restauração Dentária Permanente/métodos , Dentina/ultraestrutura , Humanos , Microscopia Eletrônica de Varredura , Dente Serotino/efeitos da radiaçãoRESUMO
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research.
Assuntos
Herpes Labial/radioterapia , Terapia com Luz de Baixa Intensidade , Animais , Antivirais/uso terapêutico , Herpes Labial/tratamento farmacológico , Humanos , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , RecidivaRESUMO
PURPOSE: To evaluate the shear bond strength (SBS) to zirconia ceramics using different associations of primers and resin cements. MATERIALS AND METHODS: Two blocks of LAVA zirconia (3Y-TZP) were randomly submitted to an application of three different commercially available primers: Alloy Primer (AP), Z-Prime Plus (ZP), and Signum Zirconia Bond (SZB). Nonprimed specimens were considered controls. After treatment, the 80 specimens (5 mm × 5 mm × 2 mm) were randomly cemented with one of the resin cements: Panavia F, Multilink, seT, and NX3. For cementation, cylinders of resin cement were built on the ceramic surfaces using the SDI SBS apparatus. The specimens were submitted to the SBS test. Fractured surfaces were observed under stereomicroscopy to determine the failure mode, and mean bond strength values were analyzed using the Kruskal-Wallis and Mann-Whitney tests (α = 0.05). RESULTS: Signum Zirconia Bond had the highest SBS compared to all other primers and the control group, regardless of the resin cement used. The highest values were obtained when associating Panavia F with Signum Zirconia Bond. Alloy Primer increased bonding values when associated with seT cement only. When no primer was used, no statistical difference was observed among resin cements. All specimens fractured due to adhesive failure. CONCLUSION: Signum Zirconia Bond is capable of increasing bonding values of resin cements to zirconia ceramics. Its association with Panavia F shows enhanced results when considering short-term adhesion to zirconia.
Assuntos
Adesivos/química , Cerâmica/química , Colagem Dentária , Materiais Dentários/química , Cimentos de Resina/química , Zircônio/química , Bis-Fenol A-Glicidil Metacrilato/química , Humanos , Teste de Materiais , Metacrilatos/química , Metilmetacrilato/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Resistência ao Cisalhamento , Propriedades de Superfície , Tionas/química , Ítrio/químicaRESUMO
UNLABELLED: This study evaluated the effects of different parameters of dentin irradiation with erbium -doped yttrium aluminum garnet (Er:YAG) laser on bond strength to dentin and analyzed the ultramorphological characteristics of resin-laser-irradiated dentin interfaces using a transmission electron microscope (TEM). Dentin surfaces were abraded with SiC paper (600 grit) or Er:YAG laser-irradiated (120/4, 140/6, 180/4, or 200/6 mJ/Hz). Three adhesive systems were tested: Single Bond Plus (3M ESPE), Clearfil Protect Bond (Kuraray Med.), and Clearfil Tri-S Bond (Kuraray Med.). Treatments were performed over flat dentin surfaces of human third molars. Specimens were stored in distilled water for 1 week or 6 months and prepared for a microtensile bond strength test and interfacial ultrastructure for analysis. Microtensile bond strength data (n = 5) were analyzed with three-way analysis of variance. Irradiation with Er:YAG laser did not reduce the bond strength values for self-etching adhesives even after 6 months of water storage. The hybrid layer formation was observed only when the adhesives were applied to non-irradiated dentin (control group). Nanoleakage occurred in all resin-dentin interfaces using Single Bond Plus for both periods. Nanoleakage pattern and bond strength of self-etching adhesives to dentin were less affected by Er:YAG laser irradiation and by the 6-month storage in water than was those of the etch-and-rinse adhesive. TEM analysis revealed no hybridization when dentin was laser-irradiated. CLINICAL SIGNIFICANCE: Minimally invasive caries removal has been proposed. Nevertheless, bonding mechanisms to lased dentin are not entirely described. Knowing the interaction between the treated dentin and bonding agents and its behavior over time is of utmost importance for new technologies. Regarding that, two-bottle self-etching adhesive system provided a more consistent evidence of its better behavior when bonding to lased substrate.
Assuntos
Dentina/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Cura Luminosa de Adesivos Dentários/métodos , Cimentos Dentários/uso terapêutico , Corrosão Dentária/métodos , Dentina/ultraestrutura , Humanos , Microscopia Eletrônica de Transmissão , Resinas Sintéticas/uso terapêutico , Propriedades de Superfície , Resistência à Tração , Fatores de TempoRESUMO
INTRODUCTION: The COVID-19 infection triggered in some patients a prolonged reduction in the perception of both gustatory and olfactory senses (ageusia and anosmia). These symptoms could be manifested during the first days after the contagion, acting as predictors of COVID-19 infection, and additionally, they could be the only symptoms manifested at all. Clinical resolution of anosmia and ageusia was expected to occur within a few weeks, yet in some cases, patients began to demonstrate COVID-19-related long-term taste impairment (CRLTTI), a condition that can persist for longer than two months, contradicting initial evidence. Objectives: The authors' aimed to describe the characteristics of the sample of 31 participants with COVID-19-related long-term taste impairment, and their capacity to quantify taste and rate their smell perception. Material and Methods: Participants were submitted to a taste evaluation of four hyper-concentrated tastes perceived by the tongue (0-10), self-reported their smell (0-10), and answered a semi-structured questionnaire. Results: Different tastes seemed to be affected differently by COVID-19, despite the lack of statistical relevance observed in this study. Dysgeusia was only expressed in bitter, sweet, and acidic tastes. The mean age observed was 40.2 (SD 12.06) years, with women representing 71% of the sample. Taste impairment persisted for an average period of 10.8 months (SD 5.7). Self-reported smell impairment was reported by the majority of participants with taste impairment. Non-vaccinated people represented 80.6% of the sample. Conclusions: COVID-19 infection could trigger taste and smell disturbances that lasted as long as 24 months. CRLTTI seems not to affect the four main taste perceptions (hyper-concentrated) equally. Women represented the majority of the sample, with an average age of 40 years (SD 12.06). Previous diseases, medication use, and behavioral aspects seem not to be linked to CRLTTI development.
RESUMO
Radiotherapy produces both acute and delayed effects on mucosal tissues, disturbing their healing. This report shows a successful treatment with laser phototherapy (LPT) on a delayed wound healing in oral mucosa previously submitted to radiotherapy with a follow up of 3 years. A 47-year-old patient treated 6 months earlier for tongue squamous cell carcinoma by surgery and radiotherapy presented with a mass in the operated area. Biopsy showed chronic inflammatory infiltrate around a residual polyglactin suture. After 2 months there was a painful mucosal dehiscence on the biopsy site. LPT was performed using a semiconductor laser with 660-nm wavelength (InGaAlP) and spot size of 0·04 cm(2) . The parameters applied were 40 mW, 4 Jcm(2) /point, 0·16 J/point, 2·4 J/session. The irradiation was performed punctually, through contact mode in 15 points (4 seconds/point), on top of and around the lesion, during ten sessions. The wound healed completely after ten sessions. This treatment proved to be conservative and effective, inducing healing of a chronic wound in a tissue previously submitted to radiotherapy.
Assuntos
Irradiação Craniana/efeitos adversos , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Mucosa Bucal/efeitos da radiação , Úlceras Orais/radioterapia , Lesões por Radiação/radioterapia , Cicatrização/efeitos da radiação , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/radioterapia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Úlceras Orais/etiologia , Úlceras Orais/patologia , Lesões por Radiação/patologia , Fatores de Tempo , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/radioterapiaRESUMO
BACKGROUND AND OBJECTIVES: This study evaluated the hybrid layer (HL) morphology created by three adhesive systems (AS) on dentin surfaces treated with Er:YAG laser using two irradiation parameters. STUDY DESIGN: Occlusal flat dentin surfaces of 36 human third molars were assigned into nine groups (n = 4) according to the following ASs: one bottle etch&rinse Single Bond Plus (3M ESPE), two-step Clearfil Protect Bond (Kuraray), and all-in-one S(3) Bond (Kuraray) self-etching, which were labeled with rhodamine B or fluorescein isothiocyanate-dextran and were applied to dentin surfaces that were irradiated with Er:YAG laser at either 120 (38.7 J/cm(2)) or 200 mJ/pulse (64.5 J/cm(2)), or were applied to untreated dentin surfaces (control group). The ASs were light-activated following MI and the bonded surfaces were restored with resin composite Z250 (3M ESPE). After 24 hours of storage in vegetable oil, the restored teeth were vertically, serially sectioned into 1-mm thick slabs, which had the adhesive interfaces analyzed with confocal laser microscope (CLSM-LSM 510 Meta). CLSM images were recorded in the fluorescent mode from three different regions along each bonded interface. RESULTS: Non-uniform HL was created on laser-irradiated dentin surfaces regardless of laser irradiation protocol for all AS, while regular and uniform HL was observed in the control groups. "Stretch mark"-like red lines were found within the HL as a result of resin infiltration into dentin microfissures, which were predominantly observed in 200 mJ/pulse groups regardless of AS. Poor resin infiltration into peritubular dentin was observed in most regions of adhesive interfaces created by all ASs on laser-irradiated dentin, resulting in thin resin tags with neither funnel-shaped morphology nor lateral resin projections. CONCLUSION: Laser irradiation of dentin surfaces at 120 or 200 mJ/pulse resulted in morphological changes in HL and resin tags for all ASs evaluated in the study.
Assuntos
Colagem Dentária/métodos , Corrosão Dentária/métodos , Dentina/citologia , Lâmpadas de Polimerização Dentária , Cimentos Dentários/classificação , Adesivos Dentinários/química , Humanos , Lasers , Lasers de Estado Sólido , Microscopia Confocal , Dente Serotino , Cimentos de Resina/química , Propriedades de Superfície/efeitos da radiação , Resistência à Tração/efeitos da radiaçãoRESUMO
The objective of this study was to evaluate the influence of various pulse widths with different energy parameters of erbium:yttrium-aluminum-garnet (Er:YAG) laser (2.94 mum) on the morphology and microleakage of cavities restored with composite resin. Identically sized class V cavities were prepared on the buccal surfaces of 54 bovine teeth by high-speed drill (n = 6, control, group 1) and prepared by Er:YAG laser (Fidelis 320A, Fotona, Slovenia) with irradiation parameters of 350 mJ/ 4 Hz or 400 mJ/2 Hz and pulse width: group 2, very short pulse (VSP); group 3, short pulse (SP); group 4, long pulse (LP); group 5, very long pulse (VLP). All cavities were filled with composite resin (Z-250-3 M), stored at 37 degrees C in distilled water, polished after 24 h, and thermally stressed (700 cycles/5-55 degrees C). The teeth were impermeabilized, immersed in 50% silver nitrate solution for 8 h, sectioned longitudinally, and exposed to Photoflood light for 10 min to reveal the stain. The leakage was evaluated under stereomicroscope by three different examiners, in a double-blind fashion, and scored (0-3). The results were analyzed by Kruskal-Wallis test (P > 0.05) and showed that there was no significant differences between the groups tested. Under scanning electron microscopy (SEM) the morphology of the cavities prepared by laser showed irregular enamel margins and dentin internal walls, and a more conservative pattern than that of conventional cavities. The different power settings and pulse widths of Er:YAG laser in cavity preparation had no influence on microleakage of composite resin restorations.
Assuntos
Preparo da Cavidade Dentária/métodos , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Animais , Bovinos , Resinas Compostas , Esmalte Dentário/efeitos da radiação , Esmalte Dentário/ultraestrutura , Infiltração Dentária/prevenção & controle , Restauração Dentária Permanente/métodos , Dentina/efeitos da radiação , Dentina/ultraestrutura , Técnicas In Vitro , Microscopia Eletrônica de VarreduraRESUMO
The aim of this in vitro study was to evaluate some parameters of dental etching when irradiated with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser. One-hundred sound human third molars were selected and randomly distributed into ten groups (n = 10). The class V cavities of group 1 (control) were prepared with a bur and etched with 37% phosphoric acid, while groups G2 to G10, were prepared with laser (5 W, 88.46 J/cm(2), 90/70% air/water) and etched with the following powers: G3 and G4, 0.25 W; G5 and G6, 0.5 W; G7 and G8, 0.75 W; G9 and G10, 1 W. Group G2 received no laser etching. Prior to restoration, G2, G4, G6, G8 and G10 received acid etching. After restoration, all samples were submitted to a microleakage test. According to statistical analysis (Kruskal-Wallis and Dunn's tests), G10 presented the lowest microleakage values (P<0.05). The other groups showed no differences between them. Etching with Er,Cr:YSGG laser (1 W) followed by phosphoric acid was effective in reducing the microleakage of class V restorations.
Assuntos
Corrosão Dentária/métodos , Restauração Dentária Permanente/métodos , Lasers de Estado Sólido/uso terapêutico , Colagem Dentária , Preparo da Cavidade Dentária , Corrosão Dentária/efeitos adversos , Restauração Dentária Permanente/efeitos adversos , Dentina/efeitos da radiação , Humanos , Técnicas In Vitro , Lasers de Estado Sólido/efeitos adversos , Dente Serotino/efeitos da radiaçãoRESUMO
The aim of this study was to evaluate the influence of erbium:yttrium-aluminum-garnet (Er:YAG) laser compared with traditional treatment on dentin permeability to calcitonin and sodium alendronate. Forty bovine roots were sectioned and divided into eight groups. Groups 1 and 2 (G1/G2) were immersed in saline solution; G1T/G2T were immersed in ethylene diamine tetra-acetic acid plus sodium lauryl ether sulfate (EDTA-T) and sodium hypochlorite (NaOCl); G1I/G2I were irradiated with Er:YAG laser (2.94 microm, 6 Hz, 40.4 J/cm(2)); G1TI/G2TI were immersed in EDTA-T, NaOCl and subjected to Er:YAG irradiation. After 4 h the radioactivity of the saline solution was measured. Statistical analysis revealed a significant difference (P < 0.05) when the groups treated with EDTA-T and NaOCl followed by Er:YAG laser irradiation were compared with the groups treated with EDTA-T only and with the groups that received no treatment. Er:YAG laser associated with traditional procedures significantly increased the diffusion of calcitonin and sodium alendronate through dentin. All groups showed calcitonin and sodium alendronate diffusion.
Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Calcitonina/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Traumatismos Dentários/tratamento farmacológico , Traumatismos Dentários/cirurgia , Alendronato/farmacocinética , Animais , Conservadores da Densidade Óssea/farmacocinética , Calcitonina/farmacocinética , Bovinos , Dentina/metabolismo , Técnicas In Vitro , Permeabilidade , Traumatismos Dentários/metabolismoRESUMO
The aim of this in vitro study was to investigate the effect of erbium:yttrium-aluminum-garnet (Er:YAG) laser irradiation on dentinal collagen by transmission electron microscopy and to analyze the resin-dentin interface by scanning electron microscopy. A tensile bond strength test was also applied. Specimens from 69 sound human third molars were randomly divided into three groups: control (no laser), and two irradiated groups, laser 250 (250 mJ/2 Hz) and laser 400 (400 mJ/4 Hz). Then, specimens were restored with two adhesive systems, an etch-and-rinse or a self-etch system. Although ultrastructural examination showed a modified surface in the irradiated dentin, there was no statistical difference in bond strength values between the laser groups and controls (P < 0.05). In conclusion, the use of Er:YAG laser for ablating human dentin did not alter the main adhesion parameters when compared with those obtained by conventional methods, thus reinforcing its use in restorative dentistry.
Assuntos
Colagem Dentária/métodos , Dentina/efeitos da radiação , Dentina/ultraestrutura , Lasers de Estado Sólido/uso terapêutico , Colágeno/efeitos da radiação , Colágeno/ultraestrutura , Cimentos Dentários , Corrosão Dentária , Restauração Dentária Permanente/métodos , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Resistência à TraçãoRESUMO
Many studies in the literature address the effect of low-power lasers in the management of pathologies related to periodontal tissues. Due to the lack of standardized information and the absence of a consensus, this review presents the current status of laser phototherapy (LPT) in periodontics and discusses its benefits and limits in the treatment of periodontal disease. The literature was searched for reviews and original research articles relating to LPT and periodontal disease. The articles were selected using either electronic search engines or manual tracing of the references cited in key papers. The literature search retrieved references on wound and bone healing, analgesia, hypersensitivity, inflammatory process and antimicrobial photodynamic therapy. Each topic is individually addressed in this review. The current literature suggests that LPT is effective in modulating different periodontal disease aspects in vitro, in animals, and in simple clinical models. Further development of this therapy is now dependent on new clinical trials with more complex study designs.