AMANDA CARAMEL JUVINO

AMANDA CARAMEL JUVINO

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Protocolos de associação de flúor e laser de alta potência (Nd:YAG) na prevenção da cárie
2022 - FONTES-OLIVEIRA, Y.R.; CARAMEL-JUVINO, A.; AVELINO, S.G.; ZEZELL, D.M.
Avaliar os protocolos publicados para prevenção da cárie utilizando associação de flúor e laser Nd:YAG. Foram utilizadas seis bases de dados: Web-of-Science, PubMed, ResearchGate, Google Acadêmico, LILACS e Scielo. Dos 115 artigos inicialmente coletados, foram excluídas as duplicatas, artigos com dentes bovinos, artigos sem flúor gel ou que abordavam erosão. Foram selecionados 12 artigos. Sobre os efeitos do tratamento, os artigos relataram que a irradiação laser promove fusão e re-solidificação da superfície, tornando-a mais ácido-resistente. Quando associado a fluoretos, este laser aumenta a superfície de contato para a ação do flúor, potencializando os seus efeitos. Analisando os parâmetros utilizados na irradiação, a maior parte (50%) usou 0,6W de potência e 84,9 J/cm² de fluência, seguido pelos valores menores 0,5W e 70,7 J/cm² (16,6%). Estes parâmetros foram considerados seguros em estudos que avaliam a possibilidade de dano térmico à polpa. Dentre os estudos que compararam os efeitos da aplicação de flúor prévia ou posteriormente à irradiação laser, apenas 8,3% relataram que o tratamento sinérgico com laser de Nd:YAG e flúor não foi mais eficaz do que o flúor isolado. Já 33,3% apresentaram melhores efeitos com a aplicação de flúor depois do laser e 8,3% obtiveram melhores resultados com aplicação antes do laser. 8,3% concluíram que o resultado independe da ordem. O protocolo de 0,6W de potência e 84,9 J/cm² de fluência, com aplicação de flúor posterior a irradiação laser, apresentou resultados satisfatórios na prevenção da cárie para a maioria dos estudos.
Avaliação da desmineralização superficial do esmalte tratado com flúor e laser utilizando Microscopia Eletrônica de Varredura
2022 - CARAMEL-JUVINO, A.; FONTES-OLIVEIRA, Y.R.; AVELINO, S.G.; ZEZELL, D.M.
Avaliar o efeito da aplicação tópica de flúor (12.300 μF-/g) associada a irradiação com laser de Nd:YAG (84 J/cm2) na desmineralização superficial do esmalte, utilizando imagens de Microscopia Eletrônica de Varredura (MEV). Utilizou-se 60 amostras de esmalte humano (CAAE: 02854118.3.0000.0075), divididas em 4 grupos: Controle Negativo, Flúor, Laser e Flúor + Laser (n=15). Após os tratamentos, os grupos foram subdivididos em 3 (n=5), para ciclagem de pH in vitro simulando três condições diferentes: pH 5 (abaixo do pH crítico do esmalte), pH 4,5 (abaixo do pH crítico do esmalte na presença do flúor) e pH 4 (investigativo). Quatro imagens por amostras foram obtidas por MEV a 15 kV, em aumento de 4.000X. As imagens foram classificadas como esmalte hígido, desmineralização leve, moderada ou severa. Para análise estatística, realizou-se uma normalização, onde a classificação de desmineralização severa foi equiparada a 100% de desmineralização, 0 foi equiparado à classificação saudável e as demais classificações foram proporcionais. Em pH 5, os grupos Flúor, Laser e Flúor + Laser não tiveram diferenças significativas entre si (p>0,05). Em pH 4,5, o grupo Flúor + Laser teve o menor percentual de desmineralização (p<0,05). Já em pH 4, não houve diferença significativa entre nenhum grupo. Os dados sugerem que o tratamento de Flúor + Laser tem ação preventiva mesmo em pH abaixo do crítico para esmalte na presença do flúor (pH 4,5). Além disso, indica que possivelmente este tratamento altera o pH crítico da estrutura para valores entre 4,5 e 4, ampliando o poder preventivo do flúor.
Analysis of ceramic laminates removal with Er,Cr:YSGG laser by optical coherence tomography
2019 - ZANINI, NATHALIA; ZAMATARO, CLAUDIA B.; RABELO, THAIS F.; JUVINO, AMANDA C.; KUCHAR, NIELSEN G.; CASTRO, PEDRO; ANA, PATRICIA da; ZEZELL, DENISE
Porcelain laminated veneers have been widely used. For wear of hard tissue such as enamel and dentin, the diamond rotary instrument is the most traditional, but the laser has become recently used to remove aesthetic facets. Optical coherence tomography (OCT) used as an optical biopsy, is important for morphological analysis and attenuation coefficient is related to the property of the photons to be scattered by the samples. After approval by the Ethics Committee, the present study investigated the detachment of 30 ceramic E-max fragments cemented in human dental enamel of dimensions 3mm x 3mm x 0.7mm with 3 types of resin cements, RelxY Veneer, Relx U200 and Variolink Veneer. The samples (Enamel + Ceramic Fragment) were randomly distributed in the 3 groups and cemented according to the manufacturer. After that, they were prepared for irradiation with the Er,Cr: YSSG laser under predetermined conditions (3.5 and 3W, 20Hz, 60% water and 40% air flow). OCT analysis was done before and after irradiation. We observed that themorphological changes of the enamel surface showed an increased surface area due to the cement remaining in the enamel.We concluded that the Er, Cr: YSGG laser, when used in the irradiation protocol tested, seems to be a safe tool for the removal of laminates.
Removal of laminates with Er,Cr:YSGG laser from dental enamel submitted to gamma radiation
2019 - RABELO, THAIS F.; ZAMATARO, CLAUDIA B.; ZANINI, NATHALIA; JUVINO, AMANDA C.; KUCHAR, NIELSEN G.; CASTRO, PEDRO A.A.; ZEZELL, DENISE M.
Background: Modern Dentistry is characterized by the search for aesthetic perfection in the smile. Many efforts are made regarding procedures related to manufacturing, cementing, maintenance and removal of ceramic laminates. The laser removal of laminates has become more frequent when the aesthetical procedures needs to be replaced. On the other hand, the head and neck cancer treatment causes comorbidities in the buccal environment when laminates are in place. Objective: To evaluate in vitro the removal of ceramic fragments by means of Er,Cr:YSGG laser irradiation, after gamma radiation. Methods: 20 Lithium disilicate veneers were cemented with Variolink to human dental enamel and then samples were irradiated with 0.07 kGy. After gamma irradiation, the laminates removal with Er,Cr:YSGG laser was performed. The control group was not subjected to gamma radiation. Dental enamel samples were analyzed by Scanning Electron Microscopy (SEM), Fourier Transformed Infrared Spectroscopy (FTIR) and Surface Microhardness Loss (SMH). Results: SEM has shown that less cement was found after removal of the facets in gamma irradiated group when compared to the control. For both groups there was alteration of the SMH possibly due to the use of the adhesive system. When performed intra group analysis, the sample being its own control of baseline in the FTIR analysis, there were no band shifts or formation of new compounds on the surface of human dental enamel. Conclusions: The Er,Cr:YSGG laser is an effective alternative for laminates removal in human dental enamel even when it is subjected to gamma radiation.
Calcium analysis of gamma sterilized human dentin submmited to Er,Cr:YSGG laser irradiation
2019 - KUCHAR, NIELSEN G.; ZAMATARO, CLAUDIA B.; RABELO, THAIS; JUVINO, AMANDA; ZANINI, NATHALIA; CASTRO, PEDRO; ZEZELL, DENISE M.
Studies report that gamma radiation changes the oral cavity of patients submitted to radiotherapy. These changes include xerostomia, resulting in an unsaturation of calciumand phosphate in the oral cavity. However, human enamel samples isolated from the altered oral environmentwhen irradiatedwithgamma radiation at doses of up to 25kGy (much higher than radiotherapy doses) were shown to have undergone no changes in molecular hardness or micro surface. After approval of the Research Ethics Committee, 20 human dentin samples were evaluated before and after irradiation, split randomly into control group (n = 10) and irradiated group (n = 10) treated with 25.0 kGy at the Co60 multipurpose irradiator and irradiated with Er,Cr:YSGG laser in the parameters: 8.5 J/cm2 in the Fourier Transform Infrared Spectroscopy (FTIR), % surface Microhardness loss and Scanning Electron Microscopy (SEM). At the end, acidic biopsies were performed to quantify the concentration of calcium present in the samples. In the results of FTIR analysis differences were found only in the bands of organic content and in the inorganic content, difference were not found between before and after irradiations. The EDS and % Surface Microhardness loss analysis corroborates these findings, as well as no significant loss of the Calcium content before and after their radiation with Co60 at 25 kGy and with the Er,Cr:YSGG laser. These findings lead us to a new hypothesis of behavior of the hydroxyapatite crystal submitted to the gamma irradiation.
Er,Cr:YSGG laser irradiation associated to fluoride for in situ model using gamma sterilized dentin and enamel
2019 - ZAMATARO, CLAUDIA B.; RABELO, THAIS F.; ZANINI, NATHALIA; JUVINO, AMANDA C.; KUCHAR, NIELSEN G.; CASTRO, PEDRO A.L.; ANA, PATRICIA A. da; ZEZELL, DENISE M.
The in situ intraoral model uses human dental enamel samples (HDE) in order to analyse the de-remineralization processes using the buccal environment without interfering into the patients’ natural dentition. The main ethical concern from this model is the biosafety. Gamma radiation is a very efficient sterilization method that is not expected to alter the mineral content of the hard tissues, avoiding biases in the results. Thus 40 HDE samples were irradiated through a source of 60Co multipurpose irradiator aiming complete sterilization (25 KGy/h) with the purpose of accumulating the native plaque on them at an in situ study. An Er,Cr:YSGG laser was used alone and in combination with the topical applications of: 1-dentifrice (1,100 lg F-/g) or 2-APF (12,300 lg F-/g). Morphological analyses were performed by scanning electron microscopy (SEM), determination of alkali-soluble fluoride concentration by specific ion electrode and microhardness determination. Then, the 15 volunteers used palatal devices containing previously treated HDE samples and remained using F dentifrice. The FTIR findings established that gamma radiation could be used aiming HDE sterilization. The Knoop hardness number was within the range of that of natural dentin of human origin. X-ray fluorescence shows that irradiated dentin has great similarity with natural dentin from the point of view of chemical composition. SEM analyses showed that there was no thermal damage or interprismatic morphological changes in the hydroxyapatite structure of human dental dentin outside the buccal environment when using doses of gamma irradiation up to 25 kGy.
In vitro determination of the critical pH demineralization of human dental enamel irradiated with Nd:YAG laser associated with fluoridated product
2019 - JUVINO, AMANDA C.; ZAMATARO, CLAUDIA B.; RABELO, THAIS F.; KUCHAR, NIELSEN G.; ZANINI, NATHALIA; CASTRO, PEDRO; ZEZELL, DENISE
The use of fluoride products associated with high intensity laser irradiation are beneficial for dental caries prevention because it increases the surface area, improving the formation of fluorapatite (FA), which gives greater acid-resistance of enamel against bacterial acids. The objective of this study is to determine the critical pH of dental enamel treated with acid fluoride phosphate 12,300 lF-/g (APF) and Nd:YAG laser 84 J/cm2, as there is no precedent to determine this pH. The study consisted of 4 groups (n = 15): G1: Negative Control; G2: APF; G3: Nd:YAG; G4: APF + Nd:YAG. Each group was randomized into three subgroups (n = 5) for pH cycling. The cycling was designed to simulate three conditions: below critical pH of enamel hydroxyapatite (pH 5.0); pH below critical for hydroxyapatite and fluorapatite (pH 4.5); condition further below the critical situation to investigate extent of acid resistance of the enamel (pH 4.0). The samples were analyzed by scanning electron microscopy (SEM), Fourier infrared spectroscopy (FTIR) and solutions were quantified fluoride (specific ion electrode) and phosphate (colorimetric method). In SEM and FTIR (phosphate band) at pH 5, only the APF and APF + Nd:YAG groups did not present demineralization. At pH 4.5, only the APF + Nd:YAG group was integrated. At pH 4, APF + Nd:YAG showed signs of mild demineralization while the other groups showed aggressive signals. It is concluded that the irradiated fluorapatite has critical dissolution pH different from fluorapatite formed only with the application of fluorine.