Radiolucência intracoronal pré-eruptiva (PECR) de um segundo molar permanente. relato de caso / Pre-eruptive intracoronal radiolucency (PECR) of a permanent second molar. case report

Introdução: A Radiolucência intracoronal pré eruptiva (PECR) é um achado radiográfico, com aspecto de lesão radiolúcida na dentina coronária, adjacente a junção amelodentinária, em dentes não irrompidos. Objetivo: Relatar um caso de possível reabsorção intracoronal pré-eruptiva com destruição extensa de dentina e envolvimento pulpar de um segundo molar permanente recém-erupcionado. Método: Após definição do diagnóstico, optou-se por um tratamento conservador, com a realização de capeamento pulpar direto com a finalidade de manutenção da vitalidade pulpar e término de formação das raízes. Resultado: Após o tratamento, paciente permaneceu assintomática no controle de quinze dias, com teste de vitalidade normal e sem sinais de inflamação. Conclusão: A interpretação cuidadosa do exame radiográfico é crucial para a detecção precoce e manejo adequado dessas lesões.

Pre-eruptive intracoronal radiolucency (PECR) is a radiographic finding, with the appearance of a radiolucent lesion in the coronary dentin, adjacent to the dentinal-enamel junction, in unerupted teeth. Objective: To report a case of possible pre-eruptive intracoronal resorption with extensive dentin destruction and pulpal involvement of a newly erupted second permanent molar. Method: After defining the diagnosis, a conservative treatment was chosen, with direct pulp capping in order to maintain pulp vitality and end root formation. Result: After treatment, the patient remained asymptomatic in the fifteen-day control, with normal vitality test and no signs of inflammation. Conclusion: Careful interpretation of the radiographic examination is crucial for early detection and proper management of these lesions.

Comparison of the effects of 2 frequencies of application of photobiomodulation on facial rejuvenation: Controlled, randomized, and double-blind clinical trial.

INTRODUCTION: Skin aging is an irreversible, slow and progressive process, mainly influenced by age, but also by external factors such as ultraviolet radiation, smoking, and alcohol, among others. It is increasingly common to look for procedures that slow down skin aging by limiting or hiding its effects on appearance. Studies have shown the benefits of photobiomodulation (PBM) for the skin, especially with the use of red light-emitting diodes. However, there is a high level of variability in the treatment parameters and frequency of application. METHODS AND ANALYSIS: The objective of this study is to compare the effects of PBM with a light-emitting diode mask (660 nm, 6.4 mW/ cm², 8,02 J/ cm², 5.02 mW, 21 minutes) on facial rejuvenation using 2 frequency applications for 4 weeks: one group will receive PBM application on the face, twice a week and another group will receive PBM application 3 times a week. A group with simulated PBM applied twice a week for 4 weeks will be used as a control. The treatment will be performed on female participants aged between 45 and 60 years. After 4 weeks, evaluations of photographic images by specialists (Wrinkle Assessment Scale) as well as the quantitative analysis of the wrinkle size by the Image J software, the depth and width of wrinkles (assessment of face impressions by optical coherence tomography) and the level of Satisfaction with Facial Appearance Overall will be compared with data collected before the start of the study. All data will be analyzed statistically according to their distribution, seeking a level of statistical significance of 0.05. ETHICS AND DISSEMINATION: This protocol was approved by the Research Ethics Committee of the Nove de Julho University (acceptance number: 4.365.565). This trial has been registered in ClinicalTrials.gov (ID: NCT04911140). This study is recruiting.

The effects of photodynamic therapy with blue light and papain-based gel associated with Urucum, on collagen and fibroblasts: a spectroscopic and cytotoxicity analysis.

Papacarie Duo™ is clinically used and has proven effectiveness; however, it is necessary to improve its antimicrobial action. The combined treatment of Papacarie Duo™ with Urucum (Bixa Orellana) could create a potential tool for dental caries treatment; its extract obtained from the seeds' pericarp contains a water-soluble primary pigment (cis-bixin) with smaller amounts of other carotenoids. The dicarboxylic acid salts of cis-norbixin and trans-norbixin occur in heated alkaline solutions. To analyze the absorption spectra and cytotoxicity (with human dermal fibroblasts) in different concentrations of Urucum, associated or not with Papacarie Duo™, we performed this in vitro study. The effects of pure Urucum, Papacarie Duo™, and PapaUrucum™ on the microstructure of collagen were also analyzed. The application of papain-based gel with Urucum did not present cytotoxicity, its exhibit UV absorption spectrum peak around 460 ± 20 nm. Also, it showed that the compound used did not alter the chemical structure of collagen. Consequently, this product could be used as a chemomechanical method to remove dentin caries as well as being a potential product for antimicrobial photodynamic therapy (aPDT) application.

Photomodulation in the treatment of chronic pain in patients with temporomandibular disorder: protocol for cost-effectiveness analysis.

INTRODUCTION: Epidemiological data show that the signs and symptoms of temporomandibular disorder (TMD) start becoming apparent from 6 years of age, and during adolescence these signs and symptoms are similar to those of adults. The present study aims to estimate the direct costs for treatment of chronic muscle pain with photobiomodulation therapy, occlusal splint and placebo in patients with TMD; to evaluate the effectiveness of photobiomodulation therapy and occlusal splint for treatment of muscle pain in patients with TMD; to analyse the cost-effectiveness of the two proposed treatments for pain; and to describe and compare the results of the analyses of these treatments. METHODS AND ANALYSIS: This is a prospective trial of clinical and economic analyses that will include 135 patientswith TMD aged between 15 years and 25 years, randomly assigned to a treatment group: G1 (photobiomodulation), G2 (occlusal splint) and G3 (placebo). The analyses will be based on the cost of each treatment during the 12-month period. The outcome of the analysis of effectiveness will be pain, measured periodically by means of clinical examination of Research Diagnostic Criteria for Temporomandibular Disorders. The cost-effectiveness ratio will be calculated using, as end points, pain and the ratio of the differences in costs between the groups studied. The evaluation of the impact of the treatment on quality of life will be determined by applying the adapted EuroQol-5D. ETHICS AND DISSEMINATION: This protocol has been ethically approved by the local medical ethical committee, protocol number 2.014.339. Results will be submitted to international peer-reviewed journals and presented at international conferences. TRIAL REGISTRATION NUMBER: NCT03096301.

Infrared Laser Improves Collagen Organization in Muscle and Tendon Tissue During the Process of Compensatory Overload.

BACKGROUND: The photobiomodulation using the low-level laser therapy (LLLT) exerts a positive modulating effect on the synthesis of collagen in skeletal muscles and tendons. However, few studies have addressed this effect during the compensatory overload. OBJECTIVE: Evaluate the effect of infrared laser on the deposition and organization of collagen fibers in muscle and tendon tissue during compensatory overload of the plantar muscle in rats. MATERIALS AND METHODS: Wistar rats were submitted to bilateral ablation of the synergist muscles of the hind paws and divided in groups: Control, Hypertrophy, and Hypertrophy (H)+LLLT (780 nm, 40 mW, 9.6 J/cm2 and 10 s/point, 8 points, total energy 3.2 J, daily), evaluated at 7 and 14 days. Muscle cuts were stained with Picrosirius-Red and hematoxylin-eosin and tendon cuts were submitted to birefringence for determination of collagen distribution and organization. RESULTS: After 7 days an increase was observed in the area between beam muscles in H+LLLT (25.45% ± 2.56) in comparison to H (20.3% ± 3.31), in mature fibers and fibrilis in H+LLLT (29346.88 µm2 ± 2182.56; 47602.8 µm2 ± 2201.86 respectively) in comparison to H (26656.5 µm2 ± 1880.46; 45630.34 µm2 ± 2805.82 respectively) and in the collagen area in H+LLLT (2.25% ± 0.19) in comparison to H (2.0% ± 0.15). However, after 14 days a reduction was observed in the area between beam muscles in H+LLLT (13.88% ± 2.54) in comparison to H (19.1% ± 2.61), in fibrils and mature fibers in H+LLLT (17174.1 µm2 ± 2563.82; 32634.04 µm2 ± 1689.38 respectively) in comparison to H (55249.86 µm2 ± 1992.65; 44318.36 µm2 ± 1759.57) and in the collagen area in H+LLLT (1.76% ± 0.16) in comparison to H (2.09 ± 0.27). A greater organization of collagen fibers in the tendon was observed after 7 and 14 days in H+LLLT groups. CONCLUSIONS: Infrared laser irradiation induces an improvement in collagen organization in tendons and a reduction in the total area of collagen in muscles during compensatory atrophy following the ablation of synergist muscles.

The Effects of Photobiomodulation Delivered by Light-Emitting Diode on Stem Cells from Human Exfoliated Deciduous Teeth: A Study on the Relevance to Pluripotent Stem Cell Viability and Proliferation.

OBJECTIVE: Photobiomodulation (PBM) can modulate the proliferation of some types of stem cells. However, few reports have addressed the effects of PBM delivered by light-emitting diode (LED) on stem cells obtained from the pulp tissue of deciduous teeth. The aim of the present study was to investigate the effect of PBM delivered by red LED (630 nm, 75 mW, 37 mW/cm2) with different radiant exposures on the cell cycle, mitochondrial membrane potential, and senescence of stem cells from human exfoliated deciduous teeth (SHED). MATERIALS AND METHODS: Cultures were irradiated with LED (2, 4, 8, 16, and 32 J/cm2). After 24 h, the cell cycle and mitochondrial membrane potential of the cultures were evaluated using flow cytometry. Nonirradiated cultures served as control. RESULTS: Cultures irradiated with 16 J/cm2 had higher percentages of cells in the synthesis phase than control cultures (p < 0.05), and no significant differences were found regarding the percentage of cells with viable mitochondria between irradiated and control cultures. No significant difference in cell senescence was found between control cultures and cultures irradiated with 2 or 16 J/cm2. CONCLUSIONS: LED irradiation at 630 nm (37 mW/cm2, 75 mW) with radiant exposure of 16 J/cm2 was capable of inducing a proliferative response in stem cells from the pulp tissue of deciduous teeth without affecting mitochondrial function or inducing senescence.

Choosing between intraoral or extraoral, red or infrared laser irradiation after impacted third molar extraction.

BACKGROUND AND OBJECTIVE: Swelling and trismus are complications experienced by nearly all subjects after undergoing oral surgery for the removal of impacted teeth. The main purpose of this paper was to compare the effects of photobiomodulation therapy (PBMT) at two different wavelengths applied intra-orally and extra-orally on facial swelling and trismus in the postoperative period following the extraction of impacted mandibular third molars. STUDY DESIGN/MATERIALS AND METHODS: Sixty subjects were randomly divided into five groups, taking into account the type of laser therapy applied after surgery (intraoral or extraoral irradiation with 660 nm laser; intraoral or extraoral irradiation with 808 nm; and sham irradiation). Two and seven days after the surgery, two blinded evaluators measured the subjects' faces (swelling), and mouth opening (trismus). RESULTS: There was a statistically significant interaction between the irradiation site and wavelength (swelling and trismus were smaller if the red laser was applied intra-orally or if infrared laser was applied extra-orally). The intra-group analyses showed that 808 nm laser applied extra-orally favored reductions in postoperative facial swelling and trismus, although the inter-group comparisons revealed no statistically significant differences. CONCLUSION: Besides energy parameters, the combination of irradiation site and wavelength drive the results of phototherapy after the removal of impacted teeth. Lasers Surg. Med. 48:511-518, 2016. © 2016 Wiley Periodicals, Inc.

Effect of low-intensity laser treatment on pain after extraction of impacted mandibular third molars: a randomised, controlled, clinical trial.

Extraction of impacted third molars is painful, so we have evaluated whether low-intensity laser could reduce the pain. Sixty patients were randomly allocated to five groups that were treated with laser immediately after extraction. Postoperative pain was evaluated after two and seven days. The Shapiro-Wilk test was used to assess whether the distribution was normal, and as it was skewed, the Kruskal-Wallis test, ANOVA and the Student-Newman-Keuls test for multiple comparisons were used to compare the groups. The Wilcoxon test was used for comparisons of pain (measured by visual analogue scale (VAS) and numerical rating scale (NRS) 101 between the second and seventh postoperative days). Probabilities of less than 0.05 were accepted as significant. We conclude that a single session of low intensity laser had no significant effect on the amount of pain under the conditions investigated.

Measurement of effective remnant power in low intensity laser after passage through the buccinator muscle in anatomical human hemifaces / Determinação da potência efetiva remanescente após a passagem do laser de baixa intensidade através do músculo bucinador em peças anatômicas/hemifaces

Objective: To determine the effective remnant power after the passage of low intensity laser of two different wavelengths (660 and 780 nm) through buccinator muscle in anatomical hemifaces. Methods: Five human hemifaces were dissected, and a laser was shone in the central region of the muscle with a receiver placed on the opposite side. The hemifaces were irradiated using the same dosimetric parameters (40 mW, 1 W/cm2, continuous mode, 0.04 cm2) and at the same point in every muscle; remnant power was measured for each irradiation. Results: The average remnant power after irradiation with 660 nm (149 ± 15 µW) light was significantly lower (p<0.0001) than with that of 780 nm (380 ± 40 µW). Conclusion: The LIL of 780 nm presented greater remnant power in comparison to the 660 nm laser after passage through the buccinator muscle, indicating the latter ́s greater penetration capacity.

Objetivo: Determinar a potência remanescente após a passagem do laser de baixa intensidade em dois comprimentos de onda (660 e 780 nm) através do músculo bucinador em peças anatômicas dissecadas. Métodos: Dissecaram-se cinco hemifaces humanas expondo o músculo bucinador. Aplicou-se o laser na região central de cada músculo, e o receptor, para aferir a potência remanescente, foi posicionado na superfície intraoral contrária. As hemifaces foram irradiadas nos mesmos parâmetros dosimétricos (40 mW, 1 W/cm2, modo contínuo, 0,04 cm2) e no mesmo ponto em cada músculo, sendo a potência remanescente aferida a cada repetição. Resultados: A potência média restante após as irradiações de 660 nm (149 ± 15 µW) foi menor (p <0,0001) que com as irradiações de 780 nm (380 ± 40 µW). Conclusão: O LBI de 780 nm apresentou maior potência remanescente que o LBI de 660 nm, após passagem pelo músculo bucinador, denotando sua maior capacidade de penetração.

Avaliação da relação entre disfunção temporomandibular e dimensão vertical de oclusão em crianças de 7 A 12 anos / Evaluation of the association between temporomandibular disorder and vertical dimension of occlusion in children and adolescents aged seven to 12 years

Objetivo verificar se existe relação entre a presença de disfunção temporomandibular (DTM) relacionada à variabilidade da dimensão vertical de oclusão em crianças e adolescentes na faixa etária de 7 a 12 anos. Métodos foram avaliadas 96 crianças e adolescentes do Instituto Rogacionista em São Paulo. A pesquisa diagnóstica da disfunção temporomandibular foi por meio do Índice de Helkimo e exame clínico posterior. Para a mensuração dos dados referentes à dimensão vertical foram empregadas as distâncias comissura labial - canto externo do olho e base do nariz – mento. A comparação dos valores médios das medidas antropométricas entre os gêneros e os grupos com e sem disfunção temporomandibular foi realizada empregando-se a análise de variância (ANOVA) complementada pelo teste least significance diference. Resultados a dimensão vertical de oclusão demonstrou medidas distintas nas crianças e adolescentes em todas as faixas etárias avaliadas, foram observadas alterações significantes dessa medida nas idades de 10 e 12 anos de ambos os gêneros. Conclusão pode -se concluir que na amostra estudada houve relação direta entre a presença  de DTM e  Dimensão vertical de oclusão (DVO), correlação positiva entre as medidas  comissura labial – canto do olho externo e Násio – Mento no sexo feminino e alterações significantes na dimensão vertical de oclusão nas idades de 10 e 12 anos para ambos os sexos. .

Purpose to establish the relationship between the presence of temporomandibular disorders and variability of vertical dimension of occlusion aged between 7 and 12 years. Methods it was analyzed 96 children and adolescents of Rogacionista Institute in Sao Paulo, Brazil. The diagnostic investigation of temporomandibular disorders was through Helkimo index and subsequent clinical examination. To measure the data on the vertical dimension were employed distances labial - corner of his eye and nose base - ment. To compare the mean values of anthropometric measurements between genders and the groups with and without TMD, we used analysis of variance (ANOVA) complemented by least significance diference test. Results the vertical dimension of occlusion showed distinct measures in children and adolescents in all age groups studied, significant changes were observed for this measure at ages 10 and 12 years of both genders. Conclusion we can conclude that in this sample there was a direct relationship between TMD and DVO, positive correlation between the measures lip commissure – corner of eye and nasium - mentum in females and significant changes in the vertical dimension of occlusion at the ages of 10 and 12 years for both sexes. .

Photodynamic therapy as novel treatment for halitosis in adolescents: a case series study.

INTRODUCTION: Halitosis is a common problem that affects a large portion of the population worldwide. The origin of this condition is oral in 90% of cases and systemic in 10% of cases. The foul odor is caused mainly by volatile sulfur compounds produced by Gram-negative bacteria. However, it has recently been found that anaerobic Gram-positive bacteria also produce hydrogen sulfide (H2S) in the presence of amino acids, such as cysteine. Light with and without the combination of chemical agents has been used to induce therapeutic and antimicrobial effects. In photodynamic therapy, the antimicrobial effect is confined to areas covered by the photosensitizing dye. The aim of the present case series study was to evaluate the antimicrobial effect of photodynamic therapy on halitosis in adolescents through the analysis of volatile sulfur compounds measured using a sulfide meter (Halimeter®). METHODS: Five adolescents aged 14 to 16 years were evaluated using a sulfide meter before and one hour after photodynamic therapy, which involved the use of methylene blue 0.005% on the middle third and posterior thirds of the dorsum of the tongue and nine points of laser irradiation in the red band (660 nm) with an energy dose of 9 J, power output of 100 mW and 90-seconds exposure time. RESULTS: A 31.8% reduction in the concentration of volatile sulfur compounds was found in the comparison of the initial and final readings. The statistically significant reduction (p = 0.0091) led to an absence of halitosis following treatment (mean: 58.2 ppb). CONCLUSION: Photodynamic therapy seems to be effective on reduction the concentration of volatile sulfur compounds.Considering the positive effects of photodynamic therapy in this case series, further studies involving microbiological analyses should be conducted to allow comparisons of the results.

DNA damage, p53, Ki-67 and COX-2 expression in rat tongue cells exposed to nandrolone decanoate.

The objective of this article was to evaluate the impact potential of nandrolone decanoate on DNA damage, cellular regulatory proteins and cyclooxygenase (COX)-2 in oral mucosa cells of Wistar rats. A total of 40 rats were distributed into four groups. Two experimental groups were treated with nandrolone decanoate, at 5 mg/kg doses, subcutaneously, three times a week in two periods: 15 and 30 days. The remaining groups received only 0.9% saline subcutaneously, three times a week. To evaluate genetic damage, nandrolone decanoate at 15 mg/kg dose was exposed to 24 h. In the histopathological analysis, no remarkable morphological changes were observed in tongue tissue in all groups. Significant increase in immunoexpression of Ki-67, p53, COX-2 proteins was detected in the groups treated with nandrolone decanoate during 15 and 30 days, when compared to their respective controls. A positive correlation between immunoexpression of p53 and COX-2 protein was detected following nandrolone decanoate exposure. DNA damage was induced by nandrolone decanoate in oral mucosa cells at 15 mg/kg dose. Our results suggest that nandrolone decanoate was able to alter the expression of cell cycle-related proteins, as well as to induce genetic damage and COX-2 immunoexpression in tongue cells of Wistar rats.

Evaluación de la variabilidad de la dimensión vertical de oclusión en niños y adolescentes / Evaluation of variability of vertical dimension of occlusion in children and adolescents

La reproducción correcta de la dimensión vertical de oclusión es la base para la mantención de la salud del sistema estomatognático.Algunos métodos permiten la medición facial de forma reproducible, como la comparación de la distancia Comisura labial – Ángulo del ojo, así como la distancia Nasion-Menton. El objetivo de este trabajo fue evaluar la medida de la Dimensión Vertical de Oclusión y sucorrelación con género en niños y adolescentes. Fueron evaluados 176 individuos, de los cuales 48 fueron selecionados dentro de los criterios de inclusión. La medida de la dimensión vertical de oclusión fue realizada por medio de calibrador digital y fue registrada en fichas individuales. Los datos fueron estratificados por grupo etáreo y analizados por el T-test. Valores de p menores a 0,05 fueronconsiderados significantes. Los resultados evidenciaron que la Dimensión Vertical de Oclusión demostró medidas distintas por grupoetáreo y género, variando de 47,70 mm a 70,20 mm para Ángulo externo del ojo-Comisura labial y 52, 30 mm a 70,60 mm para Nasion – Menton, en el género femenino. Se observó alteración estadísticamente significativa entre estas distancias en las edades de 10 y 12 años en el género masculino, mientras que para el género femenino no fue constatada diferencia significativa, considerando el nivel designificancia de 5%. Se concluye que es necesario el registro correcto de la Dimensión Vertical de Oclusión para la reproducción de esta medida, respetándose la diferenciación por grupo etáreo y género, dado que las alteraciones de la Dimensión Vertical de Oclusión pueden llevar al paciente a alteraciones oclusales, musculares y articulares, además de predisposición a maloclusiones.

The correct reproduction of the vertical dimension of occlusion (VDO) is the basis for restoring health to the stomatognathic system. A number of methods allow facial measurement in a safe, reproducible manner, such as the comparison of distance from the lipcommissure to corner of the eye (LC-CE) to the distance from the base of the nose to the chin (N-Ch). The aim of the present study was to determine VDO length in children between 7 and 12 years of age and the correlation of this length with gender. One hundredseventy-six children were evaluated, among which 48 fulfilled the inclusion criteria. The data were stratified by age and analyzed using the paired Student’s t-test. All p-values less than 0.05 were considered statistically significant. There were different measures of VDOwith regard to age and gender, ranging from 52.30 mm to 70.20 mm for the LC-CE distance and 52.30 mm to 70.60 mm for the N-Ch distance in the girls. There was no statistically significant difference between these distances in the ages of 10 and 12 years for malesand that the correlation between LC-EC and N-Ch was not significant for females. For women, there was a correlation between LC-EC and N-Ch, considering the significance level of 5%. There was conclude that it is necessary to measure the correct VDO and standard measures for reproduction of this measure, while the differentiation by age and gender, since the change in VDO can lead the patientto occlusal changes, muscle and joint pain, beyond the predisposition to malocclusion.

Influence of laser photobiomodulation on collagen IV during skeletal muscle tissue remodeling after injury in rats.

OBJECTIVE: The aim of the present study was to determine the effect of GaAlAs low-level laser therapy (LLLT) on collagen IV remodeling of the tibialis anterior (TA) muscle in rats after cryolesion. BACKGROUND: Considerable interest exists in skeletal muscle regeneration in situations such as repair after exercise-induced muscle injury, after muscle transplantation, in muscular dystrophy, exercise-induced muscle injury, and the recovery of strength after atrophy due to disuse. A number of studies have demonstrated the potential of LLLT in facilitating the muscle-healing process; however, no consensus is found in the literature regarding the best laser-irradiation parameters. METHODS: Adult male Wistar rats (n = 45) were used and randomly divided into three groups: control (n = 5); nontreated cryolesioned group (n = 20), and LLLT-cryolesioned group (n = 20). The cryolesioned groups were analyzed at 1, 7, 14, and 21 days after the injury procedure. Laser irradiation was performed 3 times per week on the injured region by using the GaAlAs laser (660 nm; beam spot of 0.04 cm(2), output power of 20 mW, power density of 500 mW/cm(2), and energy density of 5 J/cm(2), for 10 sec). The muscles were removed, frozen, cryosectioned, and then stained with hematoxylin-eosin for the visualization of general morphology or used for immunohistochemical analysis of collagen IV. RESULTS: It was demonstrated that LLLT promotes an increase in collagen IV immunolabeling in skeletal muscle in the first 7 days after acute trauma caused by cryoinjury, but does not modify the duration of the tissue-repair process. Even with LLLT, the injured muscle tissue needs ∼21 days to achieve the same state of organization as that in the noninjured muscle. CONCLUSION: The collagen IV content is modulated in regenerating skeletal muscle under LLLT, which might be associated with better tissue outcome, although the histologic analysis did not detect tissue improvement in the LLLT group.

Estudo do grau de polarização linear em lesões de pele irradiadas com laser durante o processo de cicatrização / Study of linear polarization degree in skin lesions irradiated with laser during the healing process

Introdução: Alguns dos fatores determinantes na resposta fotobiológica da terapia laser em baixa intensidade são o estado fisiológico do tecido e as características ópticas do feixe, como a polarização de seu campo elétrico. Objetivos: Investigaram-se o grau e a preservação da polarização linear em amostras de pele de rato sadia e lesionada. Métodos: Criolesões foram realizadas no dorso de ratos e tratadas por quatro dias com 1J/cm2. O campo elétrico do laser foi alinhado a 0º e a 90º em relação à coluna vertebral dos animais. Resultados: A polarização foi mantida nas camadas superficiais da pele, sendo mais preservada na pele queimada. Durante o processo cicatricial, a lesão cujo campo elétrico foi alinhado a 0º em relação à coluna vertebral mostrou um grau de polarização semelhante àquele da pele sadia. Conclusões: O processo de reparação da pele foi influenciado pela polarização linear do feixe laser de He-Ne.

Introduction: The physiological conditions of tissue and optical characteristics of beam, like electric polarization, are some of the determining factors in the photobiological response of low intensity laser therapy. Objectives: The degree and preservation of linear polarization in samples of healthy and injured rat skin were investigated. Methods: Cryolesions were created in the lower back of rats and treated for four days with 1J/cm2. The laser electric was aligned in 0º and 90º to the backbone of the animals. Results: The polarization was maintained in the superficial layers of the skin, being better preserved in burned skin. During the wound healing, the lesion whose electric was aligned parallel to the spine showed a degree of bias similar to that of healthy skin. Conclusions: The repair process of skin was influenced by linear polarization of He-Ne laser beam.

Efeito da laserterapia de baixa potênciasobre a proliferação de mioblastos C2C12 / Effect of low-energy laser irradiation on the proliferation of C2C12 myoblasts

Os efeitos da laserterapia de baixa potência estão diretamenterelacionados aos parâmetros dosimétricos e ao tipo de laser utilizado.O objetivo do presente estudo foi avaliar o efeito de diferentes dosesde irradiação dos lasers de GaAlAs e de InGaAlP sobre a proliferaçãode mioblastos cultivados em situação de carência nutricional (modelode mimetização de injúria muscular). Os mioblastos C2C12cultivados em meio defi ciente em nutrientes foram irradiados comlaser de baixa potência de GaAlAs (660 nm) e InGaAlP (780 nm)com densidades de energia de 1,3, 2,5, 3,8 e 5 J/cm2 e 1,3, 2,5, 5e 6,3 J/cm2, respectivamente. A proliferação celular foi avaliada48 horas após a irradiação por meio da mensuração da atividademitocondrial e do ensaio de cristal violeta. Não houve diferençasignifi cativa na proliferação celular entre as culturas irradiadas eculturas de controle para qualquer um dos parâmetros. Mais estudossão necessários para determinar os parâmetros ideais da laserterapiana bioestimulação de mioblastos...

The effects of phototherapy using low-level laser depend onirradiation parameters and the type of laser used. Th e aim of thepresent study was to evaluate the eff ect of phototherapy on theproliferation of C2C12 myoblasts in cell culture under defi cientnutritional condition (muscle injury model) using low-level GaAlAsand InGaAlP lasers. C2C12 myoblasts in nutrient-defi cient mediumwere irradiated with low-level GaAlAs (660 nm) and InGaAlP (780nm) lasers with energy densities of 1.3, 2.5, 3.8 e 5 J/cm2, and 1.3,2.5, 5 e 6.3 J/cm2, respectively. Cell proliferation was assessed 48hours after irradiation by measuring the mitochondrial activity andby the crystal violet assay. Th ere were no signifi cant diff erences in cellproliferation between laser-treated myoblasts and control culturesfor any of the parameters. Further studies are necessary to determinethe correct laser parameters for the biostimulation of myoblasts...

Ocorrência de mordida aberta anterior e hábitos bucais deletérios em crianças de 4 a 6 anos / Occurrence of anterior open bite and harmful oral habits in children from 4 to 6-year old

OBJETIVO: verificar a ocorrência de mordida aberta anterior e de hábitos orais deletérios em crianças de quatro a seis anos de idade. MÉTODOS: foram avaliadas 266 crianças de quatro a seis anos incompletos, de ambos os gêneros, na cidade de Suzano - São Paulo. As avaliações constaram de aplicação de ficha de avaliação para detecção de ocorrência de hábitos bucais deletérios aos responsáveis e da realização de exame clínico constituído por avaliação da oclusão das crianças. RESULTADOS: verificou-se que 221 crianças (83,1 por cento) apresentaram pelo menos um hábito bucal deletério, sendo o mais frequente o uso de mamadeira 167 (75,6 por cento). A ocorrência simultânea de hábitos deletérios e alterações de oclusão dentária foi observada em 119 crianças (44,1 por cento da amostra) e nestas, a maior prevalência foi a presença da mordida aberta anterior, presente em 89 (79,8 por cento). CONCLUSÃO: a mordida aberta anterior (MAA) foi a alteração oclusal mais prevalente nas crianças, havendo associação estatisticamente significante entre hábitos orais deletérios, como uso de mamadeira, chupeta e ocorrência de bruxismo e presença de mordida aberta anterior.

PURPOSE: to determine the occurrence of anterior open bite and harmful oral habits in children from four to six-year old. METHODS: a total of 266 four-to-six-year-old male and female children in the city of Suzano (São Paulo, Brazil) were evaluated. An assessment chart for detecting the occurrence of harmful oral habits was administered to the guardians and clinical exams were performed for assessing occlusion in the children. RESULTS: a total of 221 children (83.1 percent) had at least one harmful oral habit, the most frequent of which was the use of a feeding bottle (n=167; 75.6 percent). The occurrence of simultaneous harmful habits and dental occlusion abnormalities was observed in 119 children (44.1 percent of the sample); among these children, the greatest prevalence was of anterior open bite (n=89; 79.8 percent). CONCLUSION: anterior open bite was the most prevalent occlusion alteration in the children and had a statistically significant association with harmful oral habits, such as the use of a bottle and/or pacifier and teeth grinding.

Effect of low-energy gallium-aluminum-arsenide and aluminium gallium indium phosphide laser irradiation on the viability of C2C12 myoblasts in a muscle injury model.

OBJECTIVE: To evaluate the effect of phototherapy on the viability of cultured C2C12 myoblasts under different nutritional conditions (muscle injury model) using low-energy gallium-aluminum-arsenide (GaAlAs) and aluminium-gallium-indium-phosphide (InGaAlP) lasers with different wavelengths and powers. BACKGROUND DATA: The beneficial effects of phototherapy using low-energy lasers depend on irradiation parameters and type of laser used, but there are no data in the literature on C2C12 myoblasts proliferation after phototherapy with GaAlAs and InGaAlP lasers. METHODS: A C2C12 cell line cultured in regular (10% fetal bovine serum, FBS) and nutrient-deficient (5% FBS) media were irradiated with low-energy GaAlAs (660 nm) and InGaAlP (780 nm) lasers with energy densities of 3.8, 6.3, and 10 J/cm2, and 3.8, 10, and 17.5 J/cm2, respectively. Cell proliferation was assessed indirectly 24 h after irradiation by measuring the mitochondrial activity and using the crystal violet assay. RESULTS: There were no significant differences in cell viability between laser-treated myoblasts and control cultures for all tested parameters after 24 h of cell culture, although cell cultures grown in regular nutrient medium supplemented with 10% FBS exhibited higher growth rates than cultures, irradiated or not, grown in nutrient-deficient medium. CONCLUSION: Laser phototherapy did not improve C2C12 viability under regular or nutrient-deficient (muscle injury model) conditions using the above parameters.

Efeito do laser na produção de óxido nítrico por células musculares submetidas a estresse nutricional / Laser effect on oxide nitric production by muscle cells submitted to a nutritional stress

Introdução: O laser de baixa potência (LBP) tem sido muito utilizado em fisioterapia principalmente no reparo muscular esquelético e nos processos inflamatórios. O objetivo deste estudo foi analisar o efeito do LBP AsGaAl Twin-Laser sobre a produção de óxido nítrico por mioblastos C2C12 cultivados sob diferentes condições nutricionais (modelo de lesão muscular). Métodos: as células C2C12 foram cultivadas em condição regular (10 por cento de soro fetal bovino, SFB) e deficiência nutricional (5 por cento de SFB) e com LBP AsGaAl (660nm) com dose de 3,8J/cm2 e em ambas as condições o óxido nítrico foi mensurado no meio de cultura. Resultados: Não houve diferença significativa na produção de óxido nítrico (NO) entre os mioblastos tratados com laser e as culturas controle nos parâmetros testados após 24h de cultivo. Conclusão: A laserterapia não aumentou a produção de NO pelos mioblastos C2C12 cultivados em situação padrão ou em deficiência nutricional (modelo de injúria muscular) nos parâmetros acima citados.

Introduction: Low-level laser therapy (LLLT) has been widely used in physical therapy, mostly on skeletal muscle healing or inflammatory processes. The aim of this in vitro study was to evaluate the effect of LLLT on the nitric oxide (NO) production by cultured C2C12 myoblasts under different nutritional conditions (muscle injury model) using low energy GaAlAs and NO production was determined in both conditions. Methods: C2C12 cell line cultured in regular (10 percent fetal bovine serum, FBS) and nutrient-deficient (5 percent FBS) media were irradiated with low-energy GaAlAs (660 nm) laser with energy density of 3.8 J/cm2. Results: There were no significant differences in NO production between laser-treated myoblasts and control cultures for tested parameters after 24 h of cell culture. Conclusion: Laser phototherapy did not increase NO production by C2C12 myoblast under regular or nutrient-deficient (muscle injury model) conditions using the above parameters.