Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
PLoS One ; 16(7): e0254893, 2021.
Article in English | MEDLINE | ID: mdl-34297748

ABSTRACT

The acquisition of Advanced Manufacturing Technologies (AMT), such as high-power fiber or CO2 laser cutting equipment, generally involves high investment levels. Its payback period is usually more extended, and there is a moderate-to-high risk involved in adopting these technologies. In this work, we present a robust model that optimizes equipment investing decisions, considers the process's technical constraint and finds an optimal production plan based on the available machinery. We propose a linear investment model based on historical demand information and take physical process parameters for a LASER cutting equipment, such as cutting speed and gas consumption. The model is then transformed into a robust optimization model which considers demand uncertainty. Second, we determine the optimal production plan based on the results of the robust optimization model and assuming that demand follows a normal distribution. As a case study, we decided on the investment and productive plan for a company that offers Laser-Beam Cutting (LBC) services. The case study validates the effectiveness of the proposed model and proves the robustness of the solution. For this specific application of the model, results showed that the optimal robust solution could increase the company's expected profits by 6.4%.


Subject(s)
Investments/economics , Lasers/standards , Manufacturing Industry/instrumentation , Models, Economic , Manufacturing Industry/economics
2.
São José dos Campos; s.n; 2020. 67 p. il., graf., Tab..
Thesis in Portuguese | BBO - Dentistry | ID: biblio-1150831

ABSTRACT

Este estudo teve como objetivo investigar os efeitos da terapia com laser de baixa intensidade (LLLT) associada ao Bio-Oss® em defeitos de tamanho crítico de ratos. Foram utilizados 72 ratos machos adultos (Rattus norvegicus, variação albinus, Wistar), com 90 dias de idade. Foram realizados defeitos ósseos na calvária com 5 mm de diâmetro. Os animais foram divididos em 4 grupos: C-Coágulo sanguíneo, B- Bio-Oss®, L- LLLT, B+L- Bio-Oss® + LLLT. Cada grupo foi subdividido de acordo com os períodos de observação de 07, 30 e 60 dias, com 6 ratos em cada subgrupo. Para LLLT uma baixa energia GaAlAs com comprimento de onda de 660 nm, foi aplicada em 5 pontos. Foram distribuídos 4 pontos de aplicação ao longo das bordas da ferida e um ponto de aplicação localizado na região central da ferida cirúrgica. A irradiação foi liberada por 12 segundos por ponto, com uma densidade total de energia de 45 J/cm2. A irradiação com laser ocorreu de forma transcirurgica em única aplicação imediatamente após o procedimento. Em 07, 30 e em 60 dias, 6 animais de cada grupo foram eutanasiados pela aplicação de anestesia geral em dose triplicada, e após os testes de sensibilidade os animais foram decapitados. Em seguida a calvária foi removida para análises histomorfométrica e imunohistoquímica. Todos os dados histomorfométricos foram submetidos a análise por ANOVA, complementado pelo teste de Tukey. O nível de significância foi de 5%. Os resultados da imunohistoquímica foram representados por scores e porcentagem. Os grupos que apresentaram maior proporção de neoformação foram os grupos L (0,39±0,13) e C (0,37±0,97), porém os grupos B e B+L tiveram maior tamanho de defeito (C-1,75±0,40, B-3,02±0,63, L-2,45±0,53, B+L-3,23±1,01). Na imunohistoquímica, aos 60 dias, os grupos B (score 4-34%) e B+L (B+L score 4­50%) apresentaram maior scores de imunomarcação para OPG e RANKL, aos 30 dias a porcentagem de imunomarcação para TRAP aumentou em todos os grupos, sendo o L o único a apresentar espécimes com score 0 (16%). Os grupos que apresentaram maior proporção de neoformação foram os grupos L e C, no entanto, os maiores valores relacionados ao volume ósseo foram encontrados nos grupos B e B+L.Todos os grupos apresentaram menores valores referente a distância entre as bordas de osso neoformado no interior do defeito ao final do experimento.Os grupos B e B+L apresentaram os maiores scores de imunomarcação para OPG, as imunomarcações para TRAP apareceram mais tardiamente no grupo L(AU)


This study aimed to investigate the effects of low-level laser therapy (LLLT) associated with Bio-Oss® on critical size defects in rats. 72 adult male rats (Rattus norvegicus, variation albinus, Wistar), 90 days old, were used. Bone defects were made in the calvaria with a diameter of 5 mm. The animals were divided into 4 groups: C-blood clot, B-Bio-Oss®, L-LLLT, B + L- Bio-Oss® + LLLT. Each group was subdivided according to the observation periods of 07, 30 and 60 days, with 6 rats in each subgroup. For LLLT a low GaAlAs energy with a wavelength of 660 nm was applied at 5 points. 4 points of application were distributed along the edges of the wound and one point of application located in the central region of the surgical wound. The irradiation was released for 12 seconds per point, with a total energy density of 45 J/cm2. Laser irradiation occurred in a trans-surgical form in a single application immediately after the procedure. At 07, 30 and 60 days, 6 animals from each group were euthanized by applying triple dose of general anesthesia, after the sensitivity tests the animals were beheaded. Then the calvaria was removed for histomorphometric and immunohistochemistry analysis. All histomorphometric data were analyzed statistically by ANOVA, complemented by the Tukey test. The level of significance was 5%. The results of immunohistochemistry were represented by scores and percentage. The groups that showed the highest proportion of neoformation were groups L (0,39±0,13) and C (0,37±0,97), but groups B and B + L had a larger defect size (C-1,75±0,40, B-3,02±0,63, L-2,45±0,53, B+L-3,23±1,01). In immunohistochemistry, at 60 days, groups B (score 4- 34%) and B + L (B+L score 4 - 50%) had higher immunostaining scores for OPG and RANKL, at 30 days the percentage of immunomarking for TRAP increased in all groups, group L was the only one to present specimens with a score 0 (16%). The groups with the highest proportion of neoformation were groups L and C, however, the highest values related to bone volume were found in groups B and B+L. All groups had lower values regarding the distance between the edges of newly formed bone inside the defect at the end of the experiment. Groups B and B+L had the highest immunostaining scores for OPG, immunomarkings for TRAP appear later in group L(AU)


Subject(s)
Bone Regeneration , Biocompatible Materials/administration & dosage , Bone Transplantation/adverse effects , Lasers/standards
3.
Rev. bras. cir. plást ; 34(1): 127-133, jan.-mar. 2019. tab
Article in English, Portuguese | LILACS | ID: biblio-994566

ABSTRACT

Introdução: Cicatrizes hipertróficas e queloides causam dano estético e funcional e são de difícil tratamento. O objetivo desta revisão foi identificar estudos prospectivos do tratamento com o laser fracionado de CO2, mostrando as alterações clínicas e histológicas e a metodologia utilizada para a avaliação das cicatrizes antes e após intervenção. Métodos: Foi realizada uma revisão eletrônica (LILACS, Medline e SciELO) de estudos publicados entre janeiro de 2004 e dezembro de 2017, com os termos "keloid/queloide", "hypertrophic scar/cicatriz hipertrófica" e "laser CO2", de acordo com o PRISMA Statement, sendo selecionados os estudos que comparassem as cicatrizes antes e depois de tratamento isolado com laser fracionado de CO2. Os dados foram analisados por dois revisores independentes. Resultados: Foram analisados 102 artigos, sendo que 7 cumpriam os critérios estabelecidos. Destes, os 7 analisaram cicatrizes hipertróficas, 2 deles também analisaram queloides, e 3 estudaram alterações histológicas. Houve diferença estatística entre os escores clínicos medidos antes e após tratamento de cicatrizes hipertróficas na maioria dos estudos, com melhora nos sintomas, na flexibilidade e altura da cicatriz. Entre os 2 estudos que analisaram os queloides, 1 deles demonstrou diferença clínica após tratamento. Nas alterações histológicas, houve diferença na orientação e densidade das fibras de colágeno e na espessura da epiderme. Conclusão: O laser fracionado de CO2 deve ser considerado como opção promissora no tratamento de cicatrizes patológicas, visto que melhora os sinais e sintomas clínicos como cor, espessura e prurido.


Introduction: Hypertrophic scars and keloids cause aesthetic and functional damages, and are difficult to treat. This review aimed to identify prospective studies on fractional CO2 laser to present the clinical and histological changes and the methodology used for the evaluation of scars before and after intervention. Methods: We conducted an electronic review (LILACS, Medline, and SciELO) of studies published between January 2004 and December 2017, using the search terms "keloid/queloide," "hypertrophic scar/cicatriz hipertrófica," and "CO2 laser ," according to the PRISMA Statement. Studies that compared scars before and after isolated treatment with fractional CO2 laser were selected. Two independent reviewers analyzed the data. Results: One hundred two articles were analyzed, of which 7 met the inclusion criteria. Of the 7 articles, all analyzed hypertrophic scars, 2 analyzed keloids in addition to hypertrophic scars, and 3 analyzed histological changes. Most studies showed a statistically significant difference in clinical scores between before and after treatment of hypertrophic scars, with improvement in symptoms, flexibility, and scar height. Between the 2 studies that analyzed keloids, 1 reported a clinical difference after treatment. The histological changes showed significant differences in the orientation and density of the collagen fibers, and in the thickness of the epidermis. Conclusion: The use of fractional CO2 laser should be considered as a promising treatment option for pathological scars, as it improves clinical signs and symptoms such as color, thickness, and pruritus.


Subject(s)
Humans , Male , Female , Cicatrix/pathology , Cicatrix, Hypertrophic/diagnosis , Keloid/diagnosis , Lasers/adverse effects , Lasers/standards
4.
Rev. bras. cir. plást ; 29(3): 404-409, jul.-sep. 2014. ilus, tab
Article in English, Portuguese | LILACS | ID: biblio-732

ABSTRACT

INTRODUÇÃO: Na prática da remoção de tatuagem, já foram utilizadas a dermo a brasão e a cirurgia. Atualmente, se utiliza o laser. O objetivo deste trabalho foi avaliar a remoção de tatuagens utilizando-se o laser Q-switched NdYAG. MÉTODO: Estudo retrospectivo, com pacientes tratados com laser Q-switched NdYAG. Foram coletados dados a partir de prontuários e fotos dos pacientes, e de contato por telefone ou e-mail. A análise estatística foi feita através da análise de distribuição, regressão multivariada e regressão logística. RESULTADOS: Foram avaliados 304 pacientes com média de idade de 29,8 anos (±7,86), sendo que 297 (97,69%) foram classificados como brancos (fotótipos I, II e III); destes, 270 (88,81%) haviam feito tatuagens profissionais. A tatuagem mais antiga tinha 360 meses e a mais recente, um mês, obtendo-se uma média de 64,56 meses (± 63,54). O tamanho das tatuagens foi, em média, de 12,92 cm, sendo preta a cor predominante, estando presente em 291(86,51%) tatuagens. A média de sessões por paciente foi de 3,77 sessões (±2,99) e o intervalo entre estas foi de 49,23 dias. Com isso, foi observado, pelo terapeuta, que 52,96% das tatuagens foram parcialmente removidas; 21,38%, não removidas; 86,51%, cicatrização normal; 8,55%, cicatriz hipertrófica, e 3,29%, queloide. Dos 304 pacientes, 26,64% (81) relataram estar satisfeitos e 58,88% (179) relataram estar parcialmente satisfeitos com o resultado. A hipocromia esteve presente em 33,55% (102) dos indivíduos. CONCLUSÕES: O laser Q-switched NdYAG é um método seguro e eficaz, apresentando bom grau de satisfação e poucos efeitos indesejáveis na remoção de tatuagem.


INTRODUCTION: Both dermabrasion and surgery have been used in the practice of tattoo removal. Currently, laser is also being used. The aim of this study is to evaluate tattoo removal with Q-switched Nd:YAG laser. METHOD: This is a retrospective study on patients treated by using Q-switched Nd:YAG laser. The data were collected from medical records and patient photographs, and through phone or e-mail contact. Statistical tests were done through the analysis of distribution, multivariate regression, and logistic regression. RESULTS: A total of 304 patients with an average age of 29.8 years (±7.86 years) were assessed. Of the total, 297 (97.69%) were classified as white (phototypes I, II, and III), 270 (88.81%) of whom had professional tattoos done. The oldest tattoo was 360 months old and the most recent was 1 month old, with an average of 64.56 months (±63.54 months). The tattoo size was, on average, 12.92 cm, with black being the predominant color (i.e., present in 291 [86.51%] tattoos). The average number of sessions per patient was 3.77 (±2.99), and the interval between sessions was 49.23 days. The therapist observed that 52.96% of the tattoos were partially removed, 21.38% were not removed, 86.51% showed normal healing, 8.55% developed a hypertrophic scar, and 3.29% developed a keloid. Of the 304 patients, 81 (26.64%) reported being satisfied and 179 (58.88%) reported being partially satisfied with the outcome. Hypochromia was present in 102 (33.55%) patients. CONCLUSIONS: Q-switched Nd:YAG laser is a safe and effective method for tattoo removal that results in a good degree of patient satisfaction and few undesirable effects.


Subject(s)
Humans , Male , Female , Adult , History, 21st Century , Phenotype , Tattooing , Wound Healing , Comparative Study , Medical Records , Data Collection , Data Interpretation, Statistical , Retrospective Studies , Evaluation Study , Laser Therapy , Lasers , Tattooing/adverse effects , Tattooing/methods , Medical Records/standards , Data Collection/methods , Laser Therapy/methods , Lasers/standards
5.
Rev. bras. cir. plást ; 28(1): 124-129, jan.-mar. 2013. ilus, tab
Article in English, Portuguese | LILACS | ID: lil-687359

ABSTRACT

INTRODUÇÃO: A técnica de lipoaspiração recebeu várias contribuições desde sua primeira descrição, como modificações nas cânulas, variação na concentração da solução de infiltração e uso de aparelhos com tecnologias variadas. A utilização de aparelhos com tecnologia laser vem contribuir com o procedimento por meio da lipólise e com o estímulo de retração cutânea. Neste artigo é apresentada a experiência dos autores com a laserlipólise em 400 pacientes, no intervalo de 5 anos, sendo discutidos aspectos dos princípios da tecnologia e sua ação sobre os tecidos. MÉTODO: Estudo realizado entre julho de 2007 e julho de 2012, que incluiu 400 pacientes submetidos a procedimento de laserlipólise. Os procedimentos foram realizados seguindo protocolo original, com infiltração de soro gelado, passagem da cânula com fibra óptica para a condução da energia laser visando à laserlipólise, retração cutânea e, por último, lipoaspiração convencional. RESULTADOS: O período de internação variou de cirurgia em regime ambulatorial a pernoite. Cerca de 45% (180/400 pacientes) dos pacientes evoluíram com equimoses mínimas, com acometimento de 2% ou mais da superfície corporal comprometida. Os casos de hematoma, seroma e deiscência totalizaram 9% (36/400 pacientes). Em nenhum caso foi constatada queimadura por lesão térmica na pele. CONCLUSÕES: O procedimento de laserlipólise realizado com a técnica descrita demonstrou segurança e reprodutibilidade.


INTRODUCTION: Liposuction has undergone several improvements since its first description, including changes in the cannulas, variation in the concentration of the infiltrating solution, and the use of different devices and technologies. The use of laser technology devices for lipolysis and stimulation of skin retraction has contributed to the procedure. This article presents the authors' experience with laser lipolysis in 400 patients, within a 5-year period, and discusses the principles of the technology and its effect on tissues. METHODS: This is a study performed between July 2007 and July 2012 and included 400 patients who underwent laser lipolysis. All procedures were performed following the original protocol - infiltration of cold saline, passage of the cannula with an optic fiber for conducting the energy needed for laser lipolysis, skin retraction, and finally, conventional liposuction. RESULTS: Hospitalization type ranged from outpatient to overnight surgery. Approximately 45% (180 of 400) of patients had minimal bruising, with involvement of 2% or more of the affected body surface. Hematoma, seroma, and dehiscence occurred in a total of 9% (36 of 400) of patients. We did not find any case of thermal burn of the skin. CONCLUSIONS: Laser lipolysis performed according to the described technique was safe and reproducible.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , History, 21st Century , Lipectomy , Retrospective Studies , Connective Tissue , Guidelines as Topic , Subcutaneous Fat , Equipment and Supplies Technology , Lasers, Semiconductor , Observational Study , Lasers , Lipolysis , Lipectomy/methods , Connective Tissue/surgery , Guidelines as Topic/analysis , Guidelines as Topic/methods , Subcutaneous Fat/surgery , Lasers, Semiconductor/standards , Lasers, Semiconductor/therapeutic use , Lasers/adverse effects , Lasers/standards
6.
Caries Res ; 45(3): 294-302, 2011.
Article in English | MEDLINE | ID: mdl-21625126

ABSTRACT

This in vivo study aimed to evaluate the performance of 2 fluorescence-based methods in detecting occlusal caries lesions in primary teeth, compared with the performance of visual inspection and radiographic methods, and to propose a mathematic correction of the diagnostic parameters due to the imperfect reference standard method used in the study. Two examiners assessed the occlusal surfaces of 407 primary teeth (62 children) using visual inspection (ICDAS), radiographic, DIAGNOdent pen (pen type laser fluorescence; LFpen), and fluorescence camera (FC) methods. At the noncavitated threshold (NC) the reference standard method was the results of ICDAS, and at the dentine caries threshold (D3) teeth diagnosed with dentine caries by ICDAS or radiographic methods were subjected to operative treatment to confirm the presence of lesion. Reproducibility, sensitivity, specificity, accuracy, and the area under the ROC curve were calculated for the methods at both thresholds. At the NC threshold, LFpen had a slightly better performance compared to the FC and radiographic methods. However, at the D3 threshold, both fluorescence-based methods performed similarly. Visual inspection and radiographic methods presented higher specificities but lower sensitivities than fluorescence methods. After corrections, there was a significant decrease in some parameters. In conclusion, both fluorescence-based methods presented similar performance in detecting occlusal dentine caries lesions in primary teeth, but they usually gave more false-positive results than did the visual and radiographic methods. The correction proposed shows that the performance of the methods can be overestimated, and the correction should be validated and considered in further studies that use an imprecise reference standard method.


Subject(s)
Dental Caries/diagnosis , Lasers , Tooth, Deciduous/pathology , Area Under Curve , Child , Child, Preschool , Dental Caries/diagnostic imaging , Dental Enamel/pathology , Dentin/pathology , False Positive Reactions , Female , Fluorescence , Humans , Image Processing, Computer-Assisted/methods , Image Processing, Computer-Assisted/standards , Lasers/standards , Male , Molar/pathology , Photography, Dental/methods , Photography, Dental/standards , Physical Examination/standards , ROC Curve , Radiography, Bitewing/standards , Reference Standards , Reproducibility of Results , Sensitivity and Specificity , Tooth Crown/pathology
7.
Oral Health Prev Dent ; 6(2): 165-9, 2008.
Article in English | MEDLINE | ID: mdl-18637395

ABSTRACT

PURPOSE: To evaluate if using the laser fluorescence (LF) device improves the detection of early or more advanced occlusal caries lesions in primary teeth. MATERIALS AND METHODS: A total of 181 occlusal sites in primary teeth were assessed by one examiner using DIAGNOdent. The same examiner and a second examiner evaluated 72 of the sites again to assess intra- and inter-examiner reproducibility. After histological validation, lesions were divided at three thresholds according to the lesion depth: outer half of the enamel (D1), inner half of the enamel (D2) and dentine (D3). The sensitivity, specificity, accuracy and area under ROC curve were calculated for cut-off points for the sample considering the aforementioned thresholds. The parameters were compared using chi-square test and by comparison between unpaired ROC curves. RESULTS: The overall LF performance was better at dentine threshold than at enamel threshold. The higher specificity was found at D3 and D2, and higher accuracy at D3 (P < 0.001). The intra- and inter-examiner agreements were classified as good or excellent for all thresholds. CONCLUSIONS: The LF device performs better at the dentine threshold than at the enamel threshold. This method does not perform well in detecting initial enamel caries lesions.


Subject(s)
Dental Caries/diagnosis , Lasers , Tooth, Deciduous/pathology , Area Under Curve , Dental Caries/pathology , Dental Enamel/pathology , Dentin/pathology , Humans , Lasers/standards , Observer Variation , ROC Curve , Reproducibility of Results , Sensitivity and Specificity , Tooth Crown/pathology
8.
Eur Arch Paediatr Dent ; 8(2): 118-22, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17555695

ABSTRACT

AIM: This was to evaluate the accuracy of the different methods for diagnosing occlusal caries in vivo, and to compare their performance in primary and permanent teeth. STUDY DESIGN: Permanent teeth (199) and primary molars (65) with macroscopically intact occlusal surface, with caries lesions without cavitation (white spot) or with a darkened sulcus were selected. The teeth were examined by the following methods: visual inspection, bite-wing radiographs and DIAGNOdent. The validation method employed for asserting the existence of carious lesion was cavity preparation. RESULTS: When the total sample was taken into consideration, laser (DIAGNOdent) provided the highest accuracy (74.8%). Even when the total sample was stratified, the laser accuracy was still high for both primary (88.4%) and permanent molars (70.4%). Visual inspection also provided a high accuracy for primary teeth (83.9%). The chi-square test showed a statistically significant difference between permanent and primary teeth considering occlusal caries diagnosis (p=0.0001). The Kappa coefficient showed good inter-examiner reproducibility for all methods. McNemar test revealed that the degree of intra-examiner agreement for visual inspection was lower than for the other methods. CONCLUSIONS: As visual inspection also showed a high degree of accuracy, the laser method should be used as a complementary method in doubtful cases. Diagnostic methods of occlusal caries, in general, are more efficient in deciduous than in permanent teeth.


Subject(s)
Dental Caries/diagnosis , Lasers , Physical Examination/standards , Radiography, Bitewing/standards , Adolescent , Child , Dental Cavity Preparation , Humans , Lasers/standards , Molar/pathology , Observer Variation , Physical Examination/statistics & numerical data , Radiography, Bitewing/statistics & numerical data , Reproducibility of Results , Tooth, Deciduous/pathology
9.
Braz. oral res ; 20(3): 231-234, Jul.-Sept. 2006. ilus, graf, tab
Article in English, Portuguese | LILACS | ID: lil-435811

ABSTRACT

Apical sealing is essential for the success of paraendodontic surgery, so any procedure that may favor an adequate sealing of the apical remainder should be performed. The purpose of this study was to evaluate the influence of diode laser irradiation on the apical sealing of root-end cavities with MTA retrofillings. Root canals in twenty extracted human teeth were shaped with K-files and filled with gutta-percha. The apexes were cut off and root-end preparations were performed. The roots were divided randomly in 2 groups. Group 1 (ten specimens) was retrofilled with MTA. Group 2 was irradiated with diode laser, with 1 W for 20 seconds, on the apical surface and root end cavity before retrofilling with MTA. The specimens had their external surfaces impermeabilized with cyanoacrylate, except for the apical surface, and were then immersed in 1 percent rhodamine B dye for 72 h and placed in plaster stone. After that, the specimens were submitted to longitudinal abrasion until half of the root remained. The linear dye leakage was observed in these mid-roots between the root canal wall and retrofilling. The linear dye leakage was measured with Image Lab software, and the results were statistically analyzed with Student's t test. There were no statistically significant differences between the two groups (p > 0.05). The diode laser irradiation did not improve the apical sealing of MTA retrofillings under the conditions of this in vitro study.


O selamento apical é fundamental para o sucesso da cirurgia parendodôntica. Assim, procedimentos que melhorem o selamento do remanescente apical devem ser utilizados. O objetivo deste estudo foi verificar se a irradiação de laser de diodo poderia aumentar o selamento apical em cavidades retrógradas obturadas com MTA. Foram utilizadas 20 raízes de dentes humanos extraídos que, após preparo com lima tipo K, tiveram seus canais obturados com guta-percha. Os ápices foram cortados e sofreram preparo de cavidades retrógradas. As raízes foram divididas aleatoriamente em 2 grupos. O grupo 1 (dez espécimes) foi retrobturado com MTA, e o grupo 2 sofreu irradiação de laser de diodo na potência de 1 W por 20 s na superfície apical e na cavidade retrógrada antes da obturação com MTA. Os espécimes foram impermeabilizados externamente com cianoacrilato, com exceção da superfície apical, imersos em corante rodamina B a 1 por cento por 72 h, incluídos em gesso e posteriormente desgastados no sentido longitudinal até obter-se metade da raiz. Foi feita a leitura da infiltração linear do corante nessas hemi-raízes, entre a parede do canal radicular e a retroobturação, com auxílio do programa de computação Image Lab. Os resultados foram analisados estatisticamente pelo Teste t de Student. Não houve diferença estatística significante entre os dois grupos (p > 0,05). A irradiação com laser de diodo não proporcionou aumento do selamento apical em retrobturações com MTA sob as condições do presente estudo in vitro.


Subject(s)
Humans , Aluminum Compounds/standards , Calcium Compounds/standards , Dentin Permeability , Lasers/standards , Retrograde Obturation/methods , Root Canal Filling Materials/standards , Root Canal Preparation/instrumentation , Dental Leakage/therapy , Gutta-Percha/standards , Indicators and Reagents , Retrograde Obturation/instrumentation , Retrograde Obturation/standards
10.
Braz. oral res ; 19(4): 243-248, Oct.-Dec. 2005. tab
Article in English | LILACS | ID: lil-421123

ABSTRACT

A redução da prevalência de cáries não ocorreu uniformemente para todas as superfícies dentárias. Como as superfícies oclusais ainda são as mais susceptíveis ao desenvolvimento de lesões, novos métodos de diagnóstico ainda estão sendo avaliados. Este estudo comparou um sistema de fluorescência a laser (DIAGNOdent – DD) com o método visual de Ekstrand na detecção de cárie oclusal. Um total de 57 terceiros molares com superfícies oclusais macroscopicamente intactas foram selecionados. Dois examinadores examinaram 110 sítios por inspecção visual (IV) e DD. Após dez dias da primeira mensuração, todos os dentes foram novamente avaliados pelos mesmos métodos. A extensão de cárie foi validada por exame histológico (40 X). Os dados foram analisados quanto a sensibilidade, especificidade, reprodutibilidade intra e interexaminador e área sob a curva ROC. O teste kappa demonstrou boa reprodutibilidade intra e interexaminadores para ambos os métodos. A IV e o DD apresentaram sensibilidade semelhante para ambos os examinadores, entretanto, a IV apresentou maior especificidade que o DD. A análise geral, através da área sob a curva ROC, mostrou que a IV teve um melhor desempenho que o DD. Concluiu-se que o critério visual proposto por Ekstrand é mais confiável para o diagnóstico de cáries oclusais. O DD deve ser considerado apenas como um coadjuvante no exame de cárie em superfícies oclusais.


Subject(s)
Humans , Dentition, Permanent , Dental Caries Activity Tests/standards , Dental Caries/pathology , Lasers , Molar, Third/pathology , Dental Caries Activity Tests/instrumentation , Dental Caries , Dental Cavity Preparation/methods , Dental Enamel/pathology , Dentin/pathology , Fluorescence , Lasers/standards , Observer Variation , Reproducibility of Results , ROC Curve , Surface Properties
11.
Braz Oral Res ; 19(4): 243-8, 2005.
Article in English | MEDLINE | ID: mdl-16491250

ABSTRACT

The reduction in caries prevalence has not occurred uniformly for all dental surfaces. As the occlusal surfaces are still the most likely sites for the development of lesions, new methods of diagnosis are still being evaluated. This study compared a laser fluorescence (LF) system (DIAGNOdent) with the Ekstrands visual system for in vitro detection of occlusal caries. A total of 57 extracted molars with macroscopically intact occlusal surfaces were selected. Two-examiners assessed 110 sites by visual inspection (VI) and LF. After ten days from the first measurement, all teeth were re-evaluated through the same methods by each examiner. Caries extension was histologically assessed (X 40). The methods were compared by means of sensitivity, specificity, intra- and inter-examiner reproducibility and area under the ROC curve. The kappas test showed good intra- and inter-examiner reproducibility for both methods. VI and LF showed similar sensitivities for both examiners, however, VI showed higher specificities than LF. The overall analysis, as demonstrated by the area under the ROC curve, showed that VI had a better performance than the LF device. It was concluded that the Ekstrands visual system is more reliable than the LF device. LF should be considered only as an adjuvant for occlusal caries diagnosis.


Subject(s)
Dental Caries Activity Tests/standards , Dental Caries/pathology , Dentition, Permanent , Lasers , Molar, Third/pathology , Dental Caries/diagnostic imaging , Dental Caries Activity Tests/instrumentation , Dental Cavity Preparation/methods , Dental Enamel/pathology , Dentin/pathology , Fluorescence , Humans , Lasers/standards , Observer Variation , ROC Curve , Radiography , Reproducibility of Results , Surface Properties
12.
Rev. bras. odontol ; 61(2): 115-119, abr.-maio 2004. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-405685

ABSTRACT

A indústria nuclear, armamentista e a engenharia mecância, entre outras, já consagraram a utilização da tecnologia da luz laser com descobertas inimagináveis. O desenvolvimento e aprimoramento do laser introduziu um novo conceito técnico na odontologia e nas suas diversas especialidades. Dos vários tipos de laseres utilizados, o de argônio vem sendo experimentado em pesquisas laboratoriais e clínicas. Dentro da dentística restauradora, o laser de argônio vem sendo utilizado com maior frequência no clareamento de dentes vitalizados e na fotopolimerização de materiais restauradores estéticos. Atavés de revisão da literatura, proporcionou-se confirmar as vantagens e elucidar as dificuldades inerentes à utilização do laser de argônio


Subject(s)
Argon/standards , Lasers/standards , Dental Caries , Tooth Bleaching
13.
Acta odontol. venez ; 40(2): 70-77, ago. 2002. ilus
Article in Spanish | LILACS | ID: lil-353175

ABSTRACT

El láser de Er:YAG, según sus aplicaciones clínicas, su medio activo y su longitud de onda, se clasifica como quirúrgico, sólido e infrarrojo. Es bien absorbido por el agua de los tejidos y tiene numerosas ventajas y aplicaciones específicas en diversas áreas de la profesión odontológica. Este artículo presenta una revisión bibliográfica de las características, aplicaciones y trabajos de investigación realizados sobre el uso del láser de Er:YAG en odontología restauradora


Subject(s)
Lasers/classification , Lasers/standards , Dental Restoration, Permanent/instrumentation , Acid Etching, Dental , Aluminum , Composite Resins , Dental Bonding , Dental Enamel , Dentin , Erbium , Photomicrography , Dental Cavity Preparation/methods , Yttrium
14.
Rev. ADM ; 57(4): 137-42, jul.-ago. 2000. ilus
Article in Spanish | LILACS | ID: lil-278271

ABSTRACT

El uso del rayo láser en odontología inició en la década de ;ps 80, principalmente el CO2 y el Nd/YAG (Neodimium/Ytrium-Aluminium-Garnet); su principal uso es en los tejidos blandos en la cavidad bucal, por ejemplo en tratamientos periodontales, en excisión de fibromas, etc., así como también el Er/YAG que se utiliza hoy en día para remover caries y perforar estructura dentaria. El uso de láser en odontología tiene sus limitaciones, ventajas y desventajas, así como cualquier otra técnica quirúrgica/operatoria. El entendimiento de las bases de la óptica láser y las reacciones de los tejidos son esenciales. Aún así el operador debe tener conocimiento de las diferentes aplicaciones para tratamiento


Subject(s)
Humans , Male , Female , Middle Aged , Carbon Dioxide/chemistry , Mouth Mucosa/radiation effects , Lasers/standards , Lasers/therapeutic use , Tooth/radiation effects , Aluminum/chemistry , Dental Caries/therapy , Erbium/chemistry , Gingivectomy/methods , Hemostasis/physiology , Dental Implantation, Endosseous/standards , Lingual Frenum/surgery , Enamel Microabrasion/methods , Neodymium/chemistry , Dental Cavity Preparation/methods , Radiation Protection/methods , Yttrium/chemistry
17.
Acta odontol. venez ; 38(1): 61-68, 2000. ilus, tab
Article in Spanish | LILACS | ID: lil-304759

ABSTRACT

Con este artículo se pretende dar comienzo a una serie de publicaciones para así plasmar todo lo relacionado con el uso de la tecnología Laser en la odontología restauradora. En este primer artículo leerá sobre los antecedentes y fundamentos físicos del rayo laser, la clasificación y tipos de laser disponibles para área de la odontología, su interrelación con los tejidos vivos, así como las precauciones a tomar durante su uso. En las siguientes publicaciones de esta serie leeremos las particularidades de cada tipo de rayo laser que es utilizado en la odontología restauradora


Subject(s)
Lasers/classification , Dental Restoration, Permanent/instrumentation , Aluminum , Argon , Wound Healing/radiation effects , Dental Enamel , Dentin , Carbon Dioxide/chemistry , Equipment Safety , Erbium , Helium , Holmium , Neodymium , Neon , Optical Fibers , Lasers/standards , Lasers/therapeutic use , Scattering, Radiation , Yttrium
18.
JBC j. bras. odontol. clín ; 2(11): 39-42, set.-out. 1998. ilus
Article in Portuguese | LILACS, BBO - Dentistry | ID: lil-298298

ABSTRACT

Este artigo trata da abordagem de duas terapêuticas, sendo uma invasiva ou cirúrgica com implante dental, e a outra näo-invasiva e coadjuvante com um aparelho laser semicondutor de baixa potência indicado para uso em odontestomatologia. Essa associaçäo permite que pós-operatórios cirúrgicos näo sejam necessariamente acompanhados de drogas sistêmicas analgésicas e antinflamatórias, devido aos efeitos característicos desse tipo de radiaçäo, representadas também por sua capacidade de estimulaçäo tecidual, levando-nos a buscar também acelerar o resultado clínico almejado. O caso clínico registra o pós-operatório de uma cirurgia com implante osseointegrado do tipo micro-mini, onde os resultados da laserterapia de baixa potência no controle da dor e edema foram surpreendentes clinicamente; além disso, na proservaçäo radiográfica levantamos a hipótese da ocorrência na aceleraçäo do fenômeno biológico e genuíno da osseointegraçäo


Subject(s)
Humans , Female , Adolescent , Dental Implantation, Endosseous , Lasers/therapeutic use , Osseointegration/radiation effects , Pain, Postoperative/radiotherapy , Edema/radiotherapy , Lasers/standards
SELECTION OF CITATIONS
SEARCH DETAIL