Clinical evaluation of in-office tooth whitening with violet LED (405 nm): A double-blind randomized controlled clinical trial.

BACKGROUND: Although there is little evidence showing the effectiveness of violet LED on in-office tooth whitening, there are some studies which have reported satisfactory results. This double-blind randomized controlled clinical trial aimed to evaluate the effect of a violet light emission diode (LED) (405 nm) system, used in-office, on tooth whitening, sensitivity, use of medication after whitening and quality of life. METHODS: Eight patients were randomized into 4 groups (n = 20): G1 - violet LED, G2 - 35% carbamide peroxide (CP) and violet LED, G3 only CP 35% and G4 35% hydrogen peroxide (HP). The color was measured using a spectrophotometer at the following times: baseline, 15 and 180days. The colorimetric changes were analyzed using measurements from the CieLab System ΔE (ΔL, Δa and Δb) and the WID (Whiteness Index for Dentistry) for the 4 groups. Tooth sensitivity was recorded via a visual analog scale (VAS). Additionally, the Psychosocial Impact of Dental. Aesthetics Questionnaire (PIDAQ) was used to evaluate quality of life. RESULTS: For the analysis of ΔL, G4 and G2 presented more brightness than G1 and G3 (p<0.05), implying that G2 is at least as good as G4 (p>0.05). For measure of Δa, G4 presented better results, standing out from the other groups. (p<0.05). For Δb, both G4 and G2 showed a greater tendency for blue color than groups G1 and G3 (p <0.05). When analyzing ∆E at the 180-day follow up, G4 produced the highest ∆E, while G3 showed the lowest ∆E. The other 2 whitening groups produced intermediate ∆E values. For ∆W, G1 and G3 significantly differed from G2 and G3. When analyzing the 180-day follow up, G2 produced the highest ∆W, while G3 showed the lowest ∆W. The other two whitening treatments produced intermediate ∆W values. As for sensitivity, only G4 patients showed dental sensitivity within 24 h of the bleaching, with pain ceasing after 48 h. For G4, 33% of the patients needed to take analgesics within the first 24 h after the first 3 whitening sessions. For PIDAQ, there was no overall decrease in score over time for any of the groups and there was no difference between them (p>0.05). CONCLUSION: Our results showed that violet LED was not able to whiten teeth at the same intensity, when used alone, as it was when associated with 35% CP, contrary to our initial hypothesis. However, given that pain was not consistently reported in G2, one could suggest that treatment with LED + 35% CP is quite similar to that of 35% HP when used for tooth whitening, but with better pain outcomes. All treatments suggested an improvement in quality of life.Clinical Trial Registry: This trial is registered at ClinicalTrials.gov; the registration number is NCT03192852 https://clinicaltrials.gov/ct2/show/NCT03192852.

Effects of Photobiomodulation in Children with Down Syndrome and Possible Sleep Bruxism: Protocol For A Randomized, Controlled, Blind, Clinical Trial: Study protocol clinical trial (SPIRIT compliant).

Hypotonia, particularly of the masticatory and oropharyngeal muscles, is 1 of the main characteristics of Down Syndrome (DS), resulting in impaired speech, chewing and swallowing. Moreover, the complete or partial obstruction of the airways during sleep may occur due to hypotonia of the tongue, leading to snoring and sleep disorders, such as obstructive apnea and sleep bruxism. OBJECTIVE:: Analyze salivary levels of dopamine and cortisol and muscle activity before and after treatment with low-level laser therapy administered to acupoints in children with DS. METHODS:: A randomized, controlled, clinical trial will be conducted. Individuals 4 to 17 years of age with a diagnosis of DS and possible sleep bruxism will be screened at the Integrated Health Clinic of Nove de Julho University. We will evaluate orofacial dysfunction (Nordic Orofacial Test - Screening questionnaire), Masseter muscle activity during sleep will be assessed by BiteStrip and the masticatory muscles will be evaluated by electromyography (BTS TMJOINT) head posture as well as salivary cortisol and dopamine. After the evaluations, the participants will be randomized into 2 groups: Grupo 1 - treatment with low-level laser therapy at a wavelength of 808 nm; Group 2 - sham treatment (simulated laser therapy). Treatment will be conducted twice per week for a total of 12 sessions. The data will be tabulated and treated using GraphPad Prism version 7.0. The Kolmogorov-Smirnov test will be used to determine the normality of the data. Variables that fit the Gaussian curve will be expressed as mean and standard deviation. The ANOVA 2-way will be used for comparisons between the groups, with the significance level set to 5% (P < .05).ClinicalTrials registration number: NCT04211870.

Preventive effect of remineralizing materials on dental erosion lesions by speckle technique: An in vitro analysis.

The aim of this in vitro study was to evaluate the preventive effect of different materials on dental erosion lesions by speckle coherent light scattering analysis. Forty bovine teeth were divided in the following groups (n = 10): 1) DURA- Preventive Treatment with Fluoride Varnish (Duraphat, Colgate-Palmolive); 2) ELX- Preventive treatment with Elmex® Erosion Protection Toothpaste (GABA International AG, Therwil, Switzerland); 3) MP- Preventive treatment with MI Paste® (GC America); and 4) REG- Preventive Treatment with Regenerate Enamel Science™ (Unilever). For all groups, each sample was divided into 3 areas: non-treatment (control); preventive treatment + erosive challenge; non-treatment + erosive challenge. The erosive challenge was carried out using Sprite® Zero soft drink (pH 2.58). After the erosive challenge, the samples were evaluated by speckle coherent light scattering method in the eroded area compared to the sound area. The results showed that there was a statistically significant difference between eroded area with and without preventive treatment, however, there was no statistically significant difference among the different preventive materials tested.

Evaluation of the effectiveness of infrared light-emitting diode photobiomodulation in children with sleep bruxism: Study protocol for randomized clinical trial.

BACKGROUND: Sleep bruxism is a masticatory muscle activity characterized as rhythmic (phasic) or nonrhythmic (tonic). In children and adolescents, etiological factors, such as breathing pattern and sleep quality, have recently been addressed in studies investigating sleep bruxism. New therapies for adults, such as botulinum toxin, have been investigated, but such techniques are not applicable for individuals in the growth and development phase. METHODS: The participants will be 76 children, which will be randomly allocated to a control group, that is group 1, absence of bruxism; group 2, children with bruxism treated with infrared light-emitting diode (LED); and group 3, bruxism treated with occlusal splint. All participants will be submitted to a clinical evaluation to evaluate muscle activity and salivary biomarkers, before and after treatments. Muscle activity will be verified by electromyography of muscles mastication, masseter and temporal, and salivary biomarkers observed will be cortisol and dopamine levels. DISCUSSION: Photobiomodulation therapy has piqued the interest of researchers, as this noninvasive method has demonstrated positive results in problems related to muscle tissues. This document describes the protocol for a proposed study to evaluate morphological and psychosocial aspects in children and adolescents with awake bruxism and their responses to photobiomodulation therapy with infrared LED. CLINICAL TRIALS:.

Evaluation of Different Dentifrice Compositions for Increasing the Hardness of Demineralized Enamel: An in Vitro Study.

This study aimed to evaluate microhardness of a dentifrice containing fluoride and arginine compared to a positive control (fluoride only) and a negative control (no fluoride) on sound and demineralized bovine enamel surfaces. Specimens were randomly assigned to different treatments that included daily pH cycling and brushing three times a day with one of the following dentifrices (n = 8): Neutraçucar (arginine and fluoride), Colgate Total 12 (fluoride) and My First Colgate (no fluoride). Enamel carious lesions were artificially created one week before the beginning of these treatments (demineralized bovine enamel (DE) groups). The same groups were also tested in sound enamel (sound bovine enamel (SE) groups). Microhardness was measured at baseline and after one, two, and five weeks of treatment using a Knoop indenter. Statistical analysis involved two-way Analysis of Variance (ANOVA) and Tukey's test. After five weeks, both Total 12 and Neutraçucar had increased the microhardness of DE specimens (p < 0.05). Only Neutraçucar had increased the microhardness of the sound enamel after five weeks of treatment. Thus, it could be concluded that arginine-based dentifrices increase the microhardness of sound and demineralized bovine enamel surfaces.

Evaluation of in-office tooth whitening treatment with violet LED: protocol for a randomised controlled clinical trial.

INTRODUCTION: In-office tooth whitening treatment using violet light emited diode (LED) (405 nm) is a novel bleaching method that causes less sensitivity while offering the same effectiveness as the gold standard (35% hydrogen peroxide, H2O2). This study describes a protocol for the first randomised controlled clinical trial to compare the effects of the two methods. METHODS AND ANALYSIS: Eighty patients will be divided into four groups: G1 violet LED; G2 violet LED +35% carbamide peroxide; G3 35% H2O2 and G4 violet LED +gingivoplasty. Colour will be measured at baseline, immediately after the first session and at the 15 and 180 days follow-up using the Vita Classical and the digital Easyshade V spectrophotometer (Vita, Zahnfabrik, Germany). Sensitivity after whitening will be measured using the Visual Analogue Scale at baseline and at each session in all groups and in all follow-ups. The tissue removed during gingivoplasty (G4) will be submitted to immunohistochemical analysis for the determination of inflammatory changes caused by violet LED. The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) will be evaluated before, as well as at established time point controls. The results will be expressed as mean and SD values. After determining the normality of the data, a one-way repeated-measures analysis of variance will be used for the comparison of data with normal distribution and the Kruskal-Wallis test will be used for data with non-normal distribution. A p<0.05 will be considered indicative of statistical significance. After determining the normality of the data, the Kruskal-Wallis test will be used for non-parametric data. Multivariate analysis of variance (MANOVA) and the Wilcoxon test will be used for comparing data from the PIDAQ. ETHICS AND DISSEMINATION: This protocol has been approved by the Human Research Ethics Committee of UniversidadeNove de Julho (certificate: 2.034.518). The findings will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT03192852; Pre-results.

Diagnosis of occlusal caries lesions in deciduous molars by coherent light scattering pattern speckle.

BACKGROUND: This study presents the correlation between laser speckle images and detection of incipient caries lesions from changs in the microstructure of the surface of tooth enamel. METHODS: We used 30 healthy deciduous molar teeth collected from the Biobank Human Teeth, Faculty of Dentistry, University of São Paulo who had carious lesions induced by the pH cycling method. The samples were evaluated for the diagnosis of caries by two methods ICDAS and speckle pattern of coherent light scattering after 5, 10 and 15days and the results were statistically analyzed using α=0.05 significance level. RESULTS: A significant difference was observed between the image of the speckle scattering of healthy and injured areas within the 3 study groups, but not when comparing the three groups, showing us that it is an innovative technique that needs further study, but can be used as a diagnostic method for the detection of early caries lesions. CONCLUSION: It can be concluded that the analysis of scattering speckle pattern is a diagnostic technique that provides information on the microstructure of the surface of tooth enamel which has sensitivity for detection of incipient caries lesions.

Controlled clinical trial addressing teeth whitening with hydrogen peroxide in adolescents: a 12-month follow-up.

OBJECTIVES:: To evaluate the colorimetric change in incisors and canines of adolescents aged 12 to 20 years submitted to at-home whitening and to evaluate satisfaction, sensitivity and discomfort during the procedures through a questionnaire. METHOD:: Thirty adolescents were randomly assigned to the following groups: 1) 6.0% hydrogen peroxide (White Class with calcium - FGM); 2) 7.5% hydrogen peroxide (White Class with calcium - FGM); 3) 10% hydrogen peroxide (Oral B 3D White - Oral-B); 4) Control group - placebo. Assessments were performed prior to treatment as well as at 7, 30, 180 and 360 days after treatment. Friedman's ANOVA was used to analyze color. The Kruskal-Wallis test followed by Dunn's post hoc test was used to compare the groups at the different evaluation times. Answers on the questionnaires were ranked, and non-parametrical tests were employed. The groups were compared in each period using the Kruskal-Wallis test followed by the Student-Newman-Keuls test. Categorical data were analyzed using Fisher's exact test, and the Wilcoxon test was used for the analysis of different periods. P-values were corrected using the Hyan-Holm step-down Bonferroni procedure. Clinicaltrials.gov: NCT01998386. RESULTS:: Similar results were obtained one month after treatment with both tooth whitening gels and whitening strips. Patients were partially satisfied with the treatment after the first and second weeks and would recommend it. All products demonstrated color stability after 12 months of follow-up. CONCLUSIONS:: The bleaching procedure was efficient, and the patients could perceive its result. Further investigations are needed to determine the effects of bleaching on young teeth.

Controlled clinical trial addressing teeth whitening with hydrogen peroxide in adolescents: a 12-month follow-up

OBJECTIVES: To evaluate the colorimetric change in incisors and canines of adolescents aged 12 to 20 years submitted to at-home whitening and to evaluate satisfaction, sensitivity and discomfort during the procedures through a questionnaire. METHOD: Thirty adolescents were randomly assigned to the following groups: 1) 6.0% hydrogen peroxide (White Class with calcium - FGM); 2) 7.5% hydrogen peroxide (White Class with calcium - FGM); 3) 10% hydrogen peroxide (Oral B 3D White - Oral-B); 4) Control group - placebo. Assessments were performed prior to treatment as well as at 7, 30, 180 and 360 days after treatment. Friedman’s ANOVA was used to analyze color. The Kruskal-Wallis test followed by Dunn’s post hoc test was used to compare the groups at the different evaluation times. Answers on the questionnaires were ranked, and non-parametrical tests were employed. The groups were compared in each period using the Kruskal-Wallis test followed by the Student-Newman-Keuls test. Categorical data were analyzed using Fisher's exact test, and the Wilcoxon test was used for the analysis of different periods. P-values were corrected using the Hyan-Holm step-down Bonferroni procedure. Clinicaltrials.gov: NCT01998386. RESULTS: Similar results were obtained one month after treatment with both tooth whitening gels and whitening strips. Patients were partially satisfied with the treatment after the first and second weeks and would recommend it. All products demonstrated color stability after 12 months of follow-up. CONCLUSIONS: The bleaching procedure was efficient, and the patients could perceive its result. Further investigations are needed to determine the effects of bleaching on young teeth.

Case Report of Photodynamic Therapy in the Treatment of Dental Caries on Primary Teeth.

INTRODUCTION: The partial removal of dental caries aiming to maintain the integrity of the pulp has been considered the therapy of choice in the treatment of deep carious lesions, as long as certain principles of diagnosis are respected. Dentists are always looking for techniques to remove the decayed tissue with biosafety, what provides more comfort to the patient especially when it comes to children. Photodynamic therapy (PDT) is an antimicrobial treatment. PapacárieMblue is a modification of the regular Papacárie, with a photosensitizer added to it. CASE REPORT: PapacárieMblue was used in a patient who had deep carious lesions in a primary molar. After 5 minutes of application, the soft and infected tissues were removed from the side walls of the cavity and, after, PDT was held in the pulp wall with red laser (660 nm), energy of 30 J, output power of 100 mW and 5 minutes of exposure time. This caused a reduction in the amount of dental tissue removed, what favored the prognosis of the dental element. After a period of 3 months, a control of the case was done and we discovered that the tooth that received the PDT was not painful and the x-ray showed an absence of lesions in the furcation. CONCLUSION: PDT with PapacárieMblue has been effective in the removal of a deep carious lesion that had a risk of pulp exposure.

Evaluation of the effectiveness of photodynamic therapy for the endodontic treatment of primary teeth: study protocol for a randomized controlled clinical trial.

BACKGROUND: The elimination of pathogenic microorganisms from the root canal system is one of the major steps required for successful endodontic treatment. The aim of the proposed study is to conduct a randomized, controlled, clinical trial for the clinical and radiographic evaluation of the effectiveness of photodynamic therapy during the endodontic treatment of primary teeth. METHODS: Thirty primary anterior teeth in children aged 3 to 6 years old will be randomly divided into 2 groups: a control group, which will receive conventional treatment, and an experimental group, which will be subjected to photodynamic therapy. Microbiological evaluations will be performed before and after endodontic treatment. Moreover, clinical and radiographic evaluations will be performed on the day of treatment as well as 1, 3 and 6 months after treatment. Comparisons will be made of the two study groups. The data will be tabulated and presented in a descriptive, analytical fashion. Depending on the distribution (normal or non-normal), either the t test, ANOVA or the Mann-Whitney test will be used for analysis of the variables. The Wilcoxon test will be used for comparisons before and after treatment. P values<0.05 (95% significance level) will be considered indicative of statistically significant differences. DISCUSSION: As successful endodontic treatment is directly related to intra-canal bacterial disinfection and considering the difficult task of endodontic treatment in primary teeth, often due to difficulties in controlling young children, the internal anatomy of root canals and root resorption, the alternative of using PDT is a painless,easy-to-administer method that does not lead to microbial resistance and can assist in the achievement of successful endodontic treatment in primary teeth by eliminating the pain children can experience due to retreatment as well as premature tooth loss. TRIAL REGISTRATION: The protocol for this study was registered with Clinical Trials number NCT02485210 on 30 july 2015.

Tooth whitening with hydrogen peroxide in adolescents: study protocol for a randomized controlled trial.

BACKGROUND: Technological innovations in dental materials have been fueled by the desire of patients to improve the esthetics of their teeth. This emphasis on esthetics has led dentists to seek resources that respect the standards established by society, but without compromising the integrity of the teeth. METHODS/DESIGN: The aim of the proposed controlled clinical trial will be to assess colorimetric changes and increased dental sensitivity in adolescent patients submitted to tooth whitening with 6% and 7.5% hydrogen peroxide using home kits with whitening strips. Adolescents aged 12 to 20 years will be allocated to different groups based on treatment (n = 16 per group): (1) placebo; (2) 6.0% hydrogen peroxide (White Class with Calcium, FGM); (3) 7.5% hydrogen peroxide (White Class with Calcium, FGM); and (4) 7.5% hydrogen peroxide (Oral B 3D White, Oral-B). After the whitening procedures, the participants will be evaluated using a visual analog scale for tooth sensitivity and digital spectrophotometry to measure changes in color. Descriptive analysis of the data will be performed. Either the chi-squared test or Fisher's exact test will be used for the determination of associations among the categorical variables. Student's t-test and analysis of variance will be used to compare mean colorimetric data. Pearson's correlation coefficients will be calculated to determine the strength of correlations among the continuous variables. DISCUSSION: This randomized trial will provide an opportunity to evaluate products such as whitening strips in comparison to other self-administered methods, especially in adolescents. TRIAL REGISTRATION: The protocol for this study was submitted to Clinical Trials in November 2013 with registration number NCT01998386.

Does the casting mode influence microstructure, fracture and properties of different metal ceramic alloys?

The aim of the present study was to evaluate the tensile strength, elongation, microhardness, microstructure and fracture pattern of various metal ceramic alloys cast under different casting conditions. Two Ni-Cr alloys, Co-Cr and Pd-Ag were used. The casting conditions were as follows: electromagnetic induction under argon atmosphere, vacuum, using blowtorch without atmosphere control. For each condition, 16 specimens, each measuring 25 mm long and 2.5 mm in diameter, were obtained. Ultimate tensile strength (UTS) and elongation (EL) tests were performed using a Kratos machine. Vickers Microhardness (VM), fracture mode and microstructure were analyzed by SEM. UTS, EL and VM data were statistically analyzed using ANOVA. For UTS, alloy composition had a direct influence on casting condition of alloys (Wiron 99 and Remanium CD), with higher values shown when cast with Flame/Air (p < 0.05). The factors 'alloy" and 'casting condition" influenced the EL and VM results, generally presenting opposite results, i.e., alloy with high elongation value had lower hardness (Wiron 99), and casting condition with the lowest EL values had the highest VM values (blowtorch). Both factors had significant influence on the properties evaluated, and prosthetic laboratories should select the appropriate casting method for each alloy composition to obtain the desired property.

Does the casting mode influence microstructure, fracture and properties of different metal ceramic alloys?

The aim of the present study was to evaluate the tensile strength, elongation, microhardness, microstructure and fracture pattern of various metal ceramic alloys cast under different casting conditions. Two Ni-Cr alloys, Co-Cr and Pd-Ag were used. The casting conditions were as follows: electromagnetic induction under argon atmosphere, vacuum, using blowtorch without atmosphere control. For each condition, 16 specimens, each measuring 25 mm long and 2.5 mm in diameter, were obtained. Ultimate tensile strength (UTS) and elongation (EL) tests were performed using a Kratos machine. Vickers Microhardness (VM), fracture mode and microstructure were analyzed by SEM. UTS, EL and VM data were statistically analyzed using ANOVA. For UTS, alloy composition had a direct influence on casting condition of alloys (Wiron 99 and Remanium CD), with higher values shown when cast with Flame/Air (p < 0.05). The factors 'alloy" and 'casting condition" influenced the EL and VM results, generally presenting opposite results, i.e., alloy with high elongation value had lower hardness (Wiron 99), and casting condition with the lowest EL values had the highest VM values (blowtorch). Both factors had significant influence on the properties evaluated, and prosthetic laboratories should select the appropriate casting method for each alloy composition to obtain the desired property.

Alternativa estética para manchas de fluorose empregando técnicas de microabrasão e clareamento em adolescentes / Alternative aesthetic to fluorosis' stains using microabrasion and bleaching techniques in young dentistry

A estética dental aliada à saúde geral é considerada um fator importante na vida do adolescente. Manchas produzidas por fluorose em níveis mais acentuados causam desconforto aos pacientes jovens e, por isso, tornam-se um desafio para o profissional que lida com essa faixa-etária. O presente trabalho relata um caso clínico de paciente adolescente portador de fluorose severa cujas manchas foram minimizadas empregando-se a técnica de microabrasão com ácido fosfórico a 37% e pedra-pomes combinada ao clareamento clínico com material clareador fotoativado à base de peróxido de hidrogênio a 35%. A combinação das técnicas abordadas nesse trabalho promoveu um resultado estético satisfatório, sendo indicada como uma alternativa viável para o uso clínico.

The aesthetic dental associated with the general health is considered an important factor for adolescent's life. High levels of fluorosis cause spots and discomfort becoming a challenge for the professional who deals with this age group. This paper reports a case of adolescent patient with a severe fluorosis which spots were treated employing the microabrasion technique (phosphoric acid at 37% and pumice stone) associated with clinical clearing using a bleaching agent (hydrogen peroxide at 35%). The combination of these both techniques has promoted a satisfactory cosmetic outcome and could be considered as a viable alternative for the clinical practice.

Propriedades ópticas e microestrutura de materiais cerâmicos de restauração dentária / Optical properties and microstructure of ceramic materials for dental restoration

O objetivo do trabalho foi o de avançar na compreensão dos mecanismos envolvidos no comportamento óptico de diferentes materiais cerâmicos em função da espessura, utilizados para restauração dentária, determinar os coeficientes de absorção e espalhamento e correlacioná-los às características microestruturais de cada material. Além disso, foi avaliada a capacidade de mascaramento e a razão de contraste do material cerâmico nas formas monolítica, em duas camadas e como restauração cimentada. Para tanto, foram analisadas quatro cerâmicas odontológicas, uma porcelana de cobertura(vítrea) e três compósitos cerâmicos infiltrados com vidro do Sistema InCeram(alumina/vidro, alumina/zircônia/vidro e espinélio/vidro), além de uma resina composta odontológica empregada como substrato resinoso e um cimento resinoso para cimentação. Os coeficientes de espalhamento e absorção foram determinados por meiodos modelos de Beer-Lambert e Kubelka-Munk a partir das curvas espectrais detransmitância e reflectância (com fundos branco e preto) geradas em um espectrofotômetro na faixa de comprimento de onda entre 300 e 800 nm. A microestrutura de cada material foi analisada por meio de microscopia eletrônica de varredura com mapeamento elementar, difração de raios X e análise química por fluorescênica de raios X. O comportamento óptico dos materiais estudados foi influenciado pelas características microestruturais do material e a pela espessura. Os valores do coeficiente de espalhamento, S, das cerâmicas avaliadas foram significativamente maiores do que os valores do coeficiente de absorção, K, na região do visível. Foram propostas equações para prever as curvas espectrais de reflectância e transmitância de bilayers e de restaurações cimentadas.

The aim of this work was to advance in the understanding of the mechanisms related tothe optical behavior of different ceramic materials as a function of thickness, used for dental restoration, to determine the absorption and scattering coefficients and to correlate them to the microstructural characteristics of each material. The masking ability and the contrast ratio of ceramic material as monolith, bilayer and cemented restoration were also evaluated. For this, four dental ceramics, one porcelain and three glass-infiltrated ceramic composites of InCeram System (alumina/glass, alumina/zirconia/glass, and spinell/glass), besides one dental composite resin used as resinous substrate and one resinous cement for luting. The scattering and absorption coefficients were determined by the Beer-Lambertand Kubelka-Munk models using spectral curves of transmittance and reflectance (withwhite and black backs) generated in a spectrophotometer in the 300 to 800 nmwavelength range. The microstructure of each material was analyzed by scanning electron microscopy with elemental mapping, X-ray diffraction, and chemical analysis byX-ray fluorescence. The optical behavior of studied materials was affected by the microstructural characteristics and thickness of the material. The values of scattering coefficient, S, of evaluated ceramics were significantly higher than the values of absorption coefficient, K, in the visible range. Equations for the prediction of reflectance and transmittance spectral curves of bilayer and cemented restorations were proposed.

Tratamento clareador conservador com peróxido de hidrogênio (35 por cento) na dentinogênese imperfeita / Conservator bleaching with hydrogen peroxide (35%) in dentinogenesis imperfecta

A reabilitação estética dos pacientes portadores de dentinogênese imperfeita, geralmente é realizada utilizando-se tratamentos restauradores, porém em casos onde ainda não ocorreu a abrasão do elemento dentário, pode-se propor um tratamento mais conservador, como o clareamento. O presente relato tem por objetivo descrever o caso de um paciente com diagnóstico de dentinogênese imperfeita tipo II, onde se optou pelo tratamento utilizando-se clareamento com agente clareador Whitness HP (FGM). No presente trabalho, a técnica de clareamento dentário, realizada em sessão única, apresentou resultados clínicos satisfatórios, demonstrando-se como uma alternativa para tratamento estético desta anomalia

Oligodontia não sindrômica em paciente infantil / Non syndromic oligodontia in pediatric patient

Alterações dentárias são comumente encontradas na clínica odontológica e, as alterações de número são muito freqüentes. Fatores como o(s) dente(s) ausente(s) afetado(s), quantidade de dentes ausentes e condição clínica dos dentes presentes na cavidade bucal podem influenciar na conduta e necessidade de tratamento odontológico. O propósito deste relato foi apresentar o caso clínico de uma criança com 5 anos com oligodontia severa, sem alterações sistêmicas ou manifestações sindrômicas que pudessem estar relacionadas. Foram discutidos os termos sinônimos, incidência e freqüência, os fatores etiológicos e as doenças ou síndromes associadas

Esthetic alternative for fluorosis blemishes with the usage of a dual bleaching system based on hydrogen peroxide at 35%.

Esthetic dental procedures in pediatric dentistry represent sources of satisfaction and realization, as much for the patient as for the professional. Lack of dental esthetics may develop psychological problems in infant as well as in adolescent patients. Blemishes produced by fluorosis appear as a challenge to the pediatric dentist and alternatives for treatment are desired. The scope of this present paper is to relate a clinical case with esthetic solution for blemishes in teeth enamel due to fluorosis. A dual system of bleaching was used (photo/chemically activated) based on hydrogen peroxide at 35% (Hi-Lite-Shofu) in a male eight-year-old patient with white fluorosis blemishes on teeth 11 and 21. The bleaching system used was efficient in bleaching teeth with white blemishes due to fluorosis, thus masking the blemishes and providing a more uniform appearance.