Correlation between fluoride release, surface hardness and diametral tensile strength of restorative glass ionomer cements.

Background: The aim of this study was to determine if there is a correlation between fluoride release, surface hardness, and diametral tensile strength of restorative glass ionomer cements (GICs). Material and Methods: Conventional (Riva Self Cure) and resin-modified (Riva Light Cure) GICs were used. Thirty-four samples (ø 6 x 3 mm) were prepared for each cement. The kinetics of fluoride release (n=4) was evaluated over 28 days using a fluoride-selective electrode (ISE 4010-C00). The analysis of surface hardness (n=10) was performed using a microhardness tester (Shimadzu HMV-2000, Japan) with a Knoop indenter and a load of 25 gf for 30 seconds. The diametral tensile strength test (n=10) was conducted on a universal testing machine at a speed of 0.75 mm/min. Fluoride release data were analyzed by two-way repeated measures ANOVA and Bonferroni post hoc test, while independent t-test was used for other analyses (α=0.05). Results: Overall, the groups showed higher fluoride release until day 7 and a progressive decrease until day 28. On day 1 and day 21, Riva Self Cure showed a higher level of release than Riva Light Cure (p=0.026). Riva Light Cure showed higher diametral tensile strength (p<0.0001) and surface hardness (p=0.034) than Riva Self Cure. A negative correlation was found, indicating that higher fluoride release is associated with lower surface hardness and diametral tensile strength. Conclusion: Fluoride release and mechanical performance are related properties of GICs, and these properties exhibit different values depending on the type of material. Resin-modified GIC release less fluoride but exhibit better mechanical performance compared to conventional GIC. Key words:Diametral Tensile Strength, Fluoride, Glass Ionomer Cement, Surface Hardness.

Association of defects of enamel with polymorphisms in the vitamin D receptor and parathyroid hormone genes.

This cross-sectional study aimed to investigate the association between developmental defects of enamel (DDE) and single nucleotide polymorphisms (SNPs) in the genes encoding the vitamin D receptor (VDR) and parathyroid hormone (PTH). Orthodontic patients receiving treatment at a dental school were selected through convenience sampling. Intra-oral photographs were used to assess DDE, which were classified according to the criteria proposed by Ghanim et al. (2015) by a single calibrated examiner (Kappa>0.80). Enamel hypoplasia, molar-incisor hypomineralization (MIH), hypomimineralized second primary molar (HSPM), and non-MIH/HSPM demarcated opacities were considered for the analysis. Genomic DNA was extracted from buccal cells. The SNPs in VDR (rs7975232) and PHT (rs694, rs6256, and rs307247) were genotyped using real-time polymerase chain reactions (PCR). Statistical analyses were performed using the PLINK software (version 1.03, designed by Shaun Purcell, EUA). Chi-square or Fisher's exact tests were performed at a significance level of 5%. Ninety-one (n=91) patients (49 females and 42 males) (mean age of 14.1±5.8 years) were included. The frequency of DDE was 38.5% (35 patients). Genotype distributions were in Hardy-Weinberg equilibrium. No significant statistical association was found between DDE and the SNPs evaluated. A borderline association (p=0.09) was observed between DDE and the CC haplotype for SNP rs7975232 in VDR. In conclusion, the selected SNPs in VDR and PTH genes were not associated with DDE in the studied samples.

Frequency and variability of nonmetric dental crown traits of primary and permanent molars in a group of orthodontic patients.

BACKGROUND: The present study aimed to assess the frequency and variation of 13 nonmetric dental crown traits (NDCT) in permanent and primary molars in German orthodontic patients. METHODS: Dental records from orthodontic patients were screened and evaluated. First and second permanent and primary upper and lower molars (from left and right sides) were assessed. Teeth with cavitated dental caries, occlusal wear, restorations and obvious dental deformities were not evaluated. The NDCT for permanent molars were identified and scored according to the odontoscopic system developed by Arizona State University Dental Anthropology System (ASUDAS). The NDCT for primary molars were identified and scored according to ASUDAS, Hanihara's method and Sciulli's method. The χ2 test was used to investigate side preference and sexual dimorphism at a significance level of p ≤ 0.050. RESULTS: A total of 163 orthodontic patients (82 males and 81 females) aged 8-14 years were included. A sexual dimorphism was observed for the hypocone in first upper permanent molar (p = 0.041). The protostylid was observed in lower permanent molars (range 2.1-10%). Males presented more hypoconulid than females (p = 0.019). Only females presented the distal trigonid crest in lower first permanent molars (p = 0.002). The most common groove pattern in primary molars was Y; male presented more Y grade than females in the lower second primary molar (p = 0.039). Asymmetry was observed in some traits, ranging from 0 to 100%. CONCLUSION: The present study showed the frequency of NDCT of molars in German orthodontic patients and demonstrated that some traits present sexual dimorphism.

Er,Cr:YSGG and 980nm diode lasers influence dentin surface volume after cariogenic challenge: in vitro study.

This study aimed to evaluate the influence of the Er,Cr:YSGG irradiation and 980-nm diode lasers on the surface roughness (SR) and volume loss (VL) of dentin subjected to cariogenic challenge. Subsequently, 130 specimens of bovine dentin were divided into the following 13 groups: NT: no treatment; FG: fluoride gel; FV: fluoride varnish; Di: 980-nm diode; Di + FG; Di + FV; FG + D; FV + Di; Er: Er,Cr:YSGG; Er + FG; Er + FV; FG + Er and FV + Er. Er,Cr:YSGG laser parameters were as follows: 0.25 W; 5.0 Hz; 4.46 J/cm2 without water and 55% air. Furthermore, the 980-nm diode laser parameters were 2.0 W; 2.0 Hz; 21.41 J/cm2. The samples from each group were subjected to pH cycling. A confocal laser scanning microscope was used to evaluate SR and VL. Difference between the volume of the reference and treated areas + DES/RE was used to determine SR and VL. The mean values of the different groups were subjected to analysis of variance and Tukey's post-hoc test. The VL values were analyzed using the Kruskal-Wallis and Dunn post-hoc test (p < 0.05). The SR of the reference area did not show a statistically significant 1807-3107-bor-38-e025treatment and cariogenic challenge (p > 0.05). Moreover, VL in the FV + Di and FV + Er groups showed a statistically significant difference compared with areas submitted to different types of treatment and cariogenic challenge (p > 0.05). Er,Cr:YSGG and 980-nm diode lasers associated with fluoride varnishes decreased dentin VL in bovine teeth submitted to cariogenic challenge.

Influence of Er:YAG and ND:YAG laser irradiation and fluoride application on surface roughness and dentin surface wear after erosive challenge - An in vitro study.

Background: To evaluate the effectiveness of Er:YAG and Nd:YAG laser on dentin hypersensitivity prevention, associated or not to acidulated phosphate fluoride (APF) after erosive challenge. Material and Methods: 104 specimens were obtained from bovine dentine and divided into groups (n=13): G1: Er:YAG; G2: Er:YAG followed by application of APF; G3: application of APF followed by Er:YAG, simultaneously; G4: Nd:YAG; G5: Nd:YAG followed by application of APF; G6: application of APF followed by Nd:YAG, simultaneously; G7:application of APF; G8: untreated. The parameters for Er:YAG were:10s, distance of 4mm, water cooling flow of 2mL/min, 2Hz, 3.92J/cm2. For the Nd:YAG: 10s, distance of 1mm, without cooling, 10Hz, 70.7J/cm2. The erosive drink was a cola at 4°C, 3×/day for 1 minute, for 5 days. Roughness and wear analysis were done in confocal laser microscope. Data were statistically analyzed (α=0.05). Results: As regards roughness, there was no statistically difference among the groups. The groups irradiated with Er:YAG had a volume loss lower. G6 showed higher values than the groups irradiated with Er:YAG and lower than the other groups. The other groups irradiated with Nd:YAG showed similar wear results to the control. Conclusions: The Er:YAG laser showed the lowest volume loss from wear analysis, suggesting the increased the acid resistance of dentin. Key words:Dentine sensitivity, Lasers, Sodium fluoride.

Influence of preventive remineralizing techniques on surface roughness and volume loss of dentin submitted to erosive and/or abrasive challenges.

Background: The objective this study was to evaluate the influence of preventive remineralizing techniques on surface roughness and volume loss of dentin submitted to erosive and/or abrasive challenges. Material and Methods: One hundred and eighty specimens of bovine root dentin were made; half of each was isolated (without treatment - WT) and half was subjected to the following remineralizing techniques: fluoride varnish (FV); Regenerate Boosting Serum® (RBS); Er,Cr:YSGG laser (L); fluoride varnish+laser (FV+L); Regenerate Boosting Serum®+laser (RBS+L). The specimens were submitted to erosive, abrasive and erosive followed by abrasive challenge. Erosion was carried out for 5 minutes, twice a day for 10 days. Abrasion was performed with an electric toothbrush and slurry solution for 60 seconds. The evaluation was performed by confocal laser scanning microscopy. Analysis of variance and Tukey tests were used for surface roughness; volume loss comparison was performed using the Kruskal-Wallis test and Dunn's post-hoc (p<0.05). Results: There was no statistically significant difference in the surface roughness of the reference area in relation to the areas submitted to different types of treatment and challenges (p>0.05). Regarding volume loss, the untreated group submitted to erosive/abrasive challenges showed greater percentage of volume loss compared to the other groups (p<0.05). Conclusions: It is concluded that preventive remineralizing techniques are effective in maintaining dentin volume after erosive/abrasive challenges. Key words:YSGG lasers, Dentin, Erosion, Tooth Abrasion.

Association of defects of enamel with polymorphisms in the vitamin D receptor and parathyroid hormone genes

Abstract This cross-sectional study aimed to investigate the association between developmental defects of enamel (DDE) and single nucleotide polymorphisms (SNPs) in the genes encoding the vitamin D receptor (VDR) and parathyroid hormone (PTH). Orthodontic patients receiving treatment at a dental school were selected through convenience sampling. Intra-oral photographs were used to assess DDE, which were classified according to the criteria proposed by Ghanim et al. (2015) by a single calibrated examiner (Kappa>0.80). Enamel hypoplasia, molar-incisor hypomineralization (MIH), hypomimineralized second primary molar (HSPM), and non-MIH/HSPM demarcated opacities were considered for the analysis. Genomic DNA was extracted from buccal cells. The SNPs in VDR (rs7975232) and PHT (rs694, rs6256, and rs307247) were genotyped using real-time polymerase chain reactions (PCR). Statistical analyses were performed using the PLINK software (version 1.03, designed by Shaun Purcell, EUA). Chi-square or Fisher's exact tests were performed at a significance level of 5%. Ninety-one (n=91) patients (49 females and 42 males) (mean age of 14.1±5.8 years) were included. The frequency of DDE was 38.5% (35 patients). Genotype distributions were in Hardy-Weinberg equilibrium. No significant statistical association was found between DDE and the SNPs evaluated. A borderline association (p=0.09) was observed between DDE and the CC haplotype for SNP rs7975232 in VDR. In conclusion, the selected SNPs in VDR and PTH genes were not associated with DDE in the studied samples.

Resumo Este estudo transversal teve como objetivo investigar a associação entre defeitos de desenvolvimento do esmalte (DDE) e polimorfismos de nucleotídeo único (SNPs) nos genes que codificam o receptor da vitamina D (VDR) e o hormônio da paratireoide (PTH). Pacientes ortodônticos em tratamento em uma escola Odontologia foram selecionados por amostragem de conveniência. Os DDEs foram avaliados e classificados por um examinador calibrado (Kappa>0,80) através de fotografias intraorais de acordo com os critérios propostos por Ghanim et al. (2015). Os tipos de DDE considerados para análise foram: hipoplasia de esmalte, hipomineralização molar-incisivo (HMI), hipomineralização de segundos molares decíduos (HSMD) e opacidades demarcadas não-HMI/HSMD. O DNA gnômico foi extraído de células bucais. Os SNPs em VDR (rs7975232) e PTH (rs694, rs6256 e rs307247) foram genotipados por PCR em tempo real. As análises estatísticas foram realizadas utilizando o software PLINK (versão 1.03, concebido por Shaun Purcell, EUA). Foram feitos teste de qui-quadrado e teste exato de Fisher com um nível de significância de 5%. Foram incluídos noventa e um (n=91) pacientes (49 do sexo feminino e 42 do sexo masculino) (idade média de 14,1±5,8 anos). A frequência de DDE foi de 38,5% (35 pacientes). As distribuições genotípicas estavam em equilíbrio de Hardy-Weinberg. Não foi encontrada associação estatisticamente significante entre os DDEs e os SNPs avaliados. Foi observada uma associação limítrofe (p=0,09) entre a DDE e o haplótipo CC para o SNP rs7975232 no VDR. Em conclusão, os SNPs seleccionados nos genes VDR e PTH não foram associados à DDE nas amostras estudadas.

Er,Cr:YSGG and 980nm diode lasers influence dentin surface volume after cariogenic challenge: in vitro study

Abstract This study aimed to evaluate the influence of the Er,Cr:YSGG irradiation and 980-nm diode lasers on the surface roughness (SR) and volume loss (VL) of dentin subjected to cariogenic challenge. Subsequently, 130 specimens of bovine dentin were divided into the following 13 groups: NT: no treatment; FG: fluoride gel; FV: fluoride varnish; Di: 980-nm diode; Di + FG; Di + FV; FG + D; FV + Di; Er: Er,Cr:YSGG; Er + FG; Er + FV; FG + Er and FV + Er. Er,Cr:YSGG laser parameters were as follows: 0.25 W; 5.0 Hz; 4.46 J/cm2 without water and 55% air. Furthermore, the 980-nm diode laser parameters were 2.0 W; 2.0 Hz; 21.41 J/cm2. The samples from each group were subjected to pH cycling. A confocal laser scanning microscope was used to evaluate SR and VL. Difference between the volume of the reference and treated areas + DES/RE was used to determine SR and VL. The mean values of the different groups were subjected to analysis of variance and Tukey's post-hoc test. The VL values were analyzed using the Kruskal-Wallis and Dunn post-hoc test (p < 0.05). The SR of the reference area did not show a statistically significant 1807-3107-bor-38-e025treatment and cariogenic challenge (p > 0.05). Moreover, VL in the FV + Di and FV + Er groups showed a statistically significant difference compared with areas submitted to different types of treatment and cariogenic challenge (p > 0.05). Er,Cr:YSGG and 980-nm diode lasers associated with fluoride varnishes decreased dentin VL in bovine teeth submitted to cariogenic challenge.

Estrogen deficiency influences SEC23A gene expression in the odontogenic region of incisors ­ a murine model study / A deficiência de estrógeno influencia a expressão gênica de SEC23A na região odontogênica de incisivos ­ um estudo em modelo murino

Recent scientific evidence suggests a close relationship between estrogen deficiency and vitamin D- related genes. Estrogen and vitamin D were involved with alterations in odontogenesis and tooth eruption process. Objective: The aim of the present study was to evaluate the influence of estrogen deficiency on the expression of genes related to the activation and degradation of vitamin D in the odontogenic region of incisors in a murine model. Material and Methods: This is an experimental clinical study that used female Wistar Hannover rats. The animals were randomly divided into two groups according to the intervention received: Hypoestrogenism Group ­ animals submitted to estrogen deficiency by ovariectomy surgery and Control Group ­ animals submitted to sham surgery. Surgical intervention was performed in the prepubertal period; the animals were followed throughout the pubertal period. After euthanasia, the hemimandibles were removed to evaluate the mRNA expression of the vitamin D-related genes AMDHD1, CYP24A1, NADSYN1 and SEC23A in the odontogenic region of incisors through real time PCR. Student's t test was used to compare means. Kruskal-Wallis test and Dunn's posttest were also used. The level of significance was 5%. Results: SEC23A was overexpressed in the estrogen deficiency condition in the odontogenic region (p=0.021). Conclusion: Estrogen deficiency may influence the expression of the SEC23A gene involved in the activation and degradation of vitamin D in the odontogenic region of incisors in a murine model(AU)

Evidências científicas recentes sugerem uma estreita relação entre a deficiência de estrógeno e os genes relacionados à vitamina D. O estrógeno e a vitamina D estão envolvidos com alterações na odontogênese e no processo de erupção dentária. Objetivo: O objetivo do presente estudo foi avaliar a influência da deficiência de estrógeno na expressão de genes relacionados à ativação e degradação da vitamina D na região odontogênica de incisivos em modelo murino. Material e Métodos: Trata-se de um estudo clínico experimental que utilizou ratas Wistar Hannover fêmeas. Os animais foram divididos aleatoriamente em dois grupos de acordo com a intervenção recebida: Grupo Hipoestrogenismo ­ animais submetidos à deficiência de estrógeno pela cirurgia de ovariectomia e Grupo Controle ­ animais submetidos à cirurgia simulada. A intervenção cirúrgica foi realizada no período pré-púbere; os animais foram acompanhados durante todo o período puberal. Após a eutanásia, as hemimandíbulas foram removidas para avaliar a expressão de mRNA dos genes AMDHD1, CYP24A1, NADSYN1 e SEC23A, relacionados à vitamina D, na região odontogênica de incisivos por meio de PCR em tempo real. O teste t de Student foi utilizado para comparar as médias. Também foram utilizados o teste de Kruskal-Wallis e o pós-teste de Dunn. O nível de significância foi de 5%. Resultados: SEC23A foi superexpresso na condição de deficiência de estrógeno na região odontogênica (p=0,021). Conclusão: A deficiência de estrógeno pode influenciar a expressão do gene SEC23A envolvido na ativação e degradação da vitamina D na região odontogênica de incisivos em modelo murino (AU)

Prevalence and local causes for retention of primary teeth and the associated delayed permanent tooth eruption.

BACKGROUND: This study aimed to evaluate the prevalence of retained primary teeth (RPT) associated with delayed permanent tooth eruption and the factors associated with this condition in German children. METHODS: This is a cross-sectional retrospective study that evaluated panoramic radiographs from orthodontic patients. The diagnosis of RPT was established according to Nolla developmental stage. The primary tooth was considered retained when its successor permanent tooth was in Nolla stage 8, 9, or 10. Statistical analysis was performed with an α of 5% (p < 0.05). RESULTS: A total of 102 children (48 girls and 54 boys), and 574 primary teeth and their respective permanent successor teeth were evaluated. We classified 192 teeth as RPT. Sixty-one (59.8%) children presented one or more RPT. Gender was not significantly different between RPT and control teeth (p = 0.838; odds ratio 0.95, confidence interval 95% 0.44-2.16). In the majority of the RPT cases (68.7%), no clear cause to explain the prolonged retention was identified. The pathological problems most commonly observed with RPT were dental fillings (19.3%), followed by dental caries (4.6%), and ectopic tooth eruption (2.1%). CONCLUSIONS: The incidence of RPT associated with delayed permanent tooth eruption in German children was high and the most common pathological condition associated with RPT was dental caries.

Effect of the Case for Carpule as a Visual Passive Distraction Tool on Dental Fear and Anxiety: A Pilot Study.

The present cross-over study aimed to evaluate the effect of a visual passive distraction tool, a case for carpule, in the management of fear and anxiety during invasive dental treatment. Children between the ages of 4 and 8 years that need at least two treatments with inferior alveolar nerve block were selected. All the included children received two treatments at different moments: in one treatment, local anesthesia was performed with a visual passive distraction tool, the crocodile case, for carpule (experimental); in the other treatment, local anesthesia was performed without the device (control). An evaluation of the anxiety levels was performed by measuring the heart rate and salivary cortisol levels. Wilcoxon's nonparametric test was used for a data analysis (p < 0.05). The mean heart rate with the visual passive distraction device fell from 81.8 to 78.1, while the control rose from 91.4 to 100 (p < 0.05). The mean salivary cortisol levels with the visual passive distraction device fell from 2.0 to 1.6, while in the control, they rose from 2.1 to 2.4 (p < 0.05). In conclusion, the crocodile case for carpule as a visual passive distraction device contributed positively to the management of fear and anxiety during inferior alveolar nerve block in children.

Estrogen deficiency influences TNF-α and IL-1ß gene expression in the odontogenic region of dental hypofunctional condition / A deficiência de estrógeno influencia a expressão gênica de TNF-α e IL-1ß na região odontogênica de dentes em hipofunção

Objetivo: Evidências científicas sugerem que a deficiência de estrógeno e fatores genéticos influenciam o desenvolvimento do sistema estomatognático. Este estudo teve como objetivo avaliar a influência da deficiência de estrógeno na expressão gênica de TNF-α, IL-1ß, IL-6 e IL-10 durante o desenvolvimento dentário em modelo murino. Material e Métodos: Ratas Wistar Hannover foram divididas em dois grupos de acordo com a intervenção recebida: Grupo Hipoestrogenismo - cirurgia de ovariectomia e Grupo Controle - cirurgia fictícia. Para avaliar o desenvolvimento dentário, o incisivo inferior foi escolhido. O modelo de hipofunção dos incisivos inferiores foi realizado por ajuste incisal. O incisivo homólogo exercia hiperfunção dentária. Os animais foram avaliados durante todo o período puberal. Após a eutanásia, as hemimandíbulas foram removidas para avaliar a expressão gênica do TNF-α, IL-1ß, IL-6 e IL-10 na região odontogênica dos incisivos por meio de PCR em tempo real. Foi realizado o teste de Kruskal-Wallis e o pós-teste de Dunn. O nível de significância foi de 5%. Resultados: Houve diferenças estatisticamente significativas na expressão gênica de TNF-α e IL-1ß entre os grupos hipoestrogenismo e controle sob condição de hipofunção dentária (p=0,0084, p=0,0072, respectivamente). Conclusão: A deficiência de estrógeno influencia a expressão gênica de TNF-α e IL-1ß na região odontogênica de dentes hipofuncionais (AU)

Objective: Scientific evidence suggests that estrogen deficiency and genetic factors have an influence on the development of the stomatognathic system. This study aimed to evaluate the influence of estrogen deficiency on the gene expression of TNF-α, IL-1ß, IL-6 and IL-10 during dental development in a murine model. Material and Methods: Wistar Hannover rats were divided into two groups according to the intervention received: Hypoestrogenism Group - ovariectomy surgery and Control Group - fictitious surgery. To evaluate the dental development, the lower incisor was chosen. The mandibular incisor hypofunction model was performed by incisal adjustment. The homologous incisor exerted a hyperfunction. The animals were evaluated throughout the pubertal period. After euthanasia, the hemimandibles were removed to evaluate the gene expression of the TNF-α, IL-1ß, IL-6 and IL-10 in the odontogenic region of the incisors through real time PCR. Kruskal-Wallis test and Dunn's posttest were performed. The level of significance was 5%. Results: There were statistically significant differences of TNF-α and IL-1ß gene expression between the hypoestrogenism and control groups under hypofunction condition (p=0.0084, p=0.0072, respectively). Conclusion: Estrogen deficiency influences TNF-α and IL-1ß gene expression in the odontogenic region of the hypofunctional teeth. (AU)

Polyethylene terephthalate clamps: Optimization in endodontic and restorative practices.

Background: There is a growing search for innovations in dental materials and instruments and, therefore, an increase need to optimize the instruments used in the absolute isolation. The gold standard procedure contributes significantly to the quality of restorative and endodontic procedures. Thus, the aim of the present study was to evaluate the radiopacity of polyethylene terephthalate polymer clamps and compare them to conventional metal clamps. Material and Methods: The polyethylene terephthalate clamp was developed at the University of Uberaba (Patent application #PI0901719-4, Uberaba, MG, Brazil). Five polyethylene terephthalate clamps and five conventional metal clamps were used. The clamps were positioned, next to an aluminum scale, under the same phosphor plate to perform 3 radiographs. The locator cylinder was set perpendicular to the radiographic films at a focal length of 20 cm and set to 60 kVp and 0.06 seconds. After image processing, optical density values were read using DBWin 5.0.4 software. The mean of the 3 readings taken on each clamp was adopted as the radiodensity of the specimen. The differences between the groups were compared using Student's t-test (p<0.05). Results: Polyethylene terephthalate clamps demonstrated significantly lower radiopacity than conventional metal clamps (p<0.05). Conclusions: Polyethylene terephthalate clamps have lower radiopacity when compared to conventional metal clamps. Key words:Rubber Dams, Dentistry, Operative, Endodontics.

Color Stability and Surface Roughness of Hybrid and Nanofilled Composites Brushed with Abrasive Dentifrices / Estabilidade de Cor e Rugosidade Superficial de Resinas Compostas Micro-Híbridas e Nanoparticulada Submetidas à Escovação com Dentifrícios Abrasivos

The aim of this study was to evaluate the color stability and the surface roughness of different composites brushed with toothpastes presenting different levels of abrasivity. Thirty discs of each material were obtained using michohybrid composites (Brilliant NG and Charisma Diamond) and a nanocomposite (Filtek Z350XT). The initial color (CIELab) and surface roughness (confocal laser scanning microscopy) of resin discs were evaluated. Afterwards, 10 specimens per group were brushed with the following dentifrices: Maximum Cavity Protection, Sensodyne Repair & Protect and Colgate Sensitive Pro-Relief. Brushing was performed with an electric toothbrush equipped with soft bristle head, with standard power and weight, for 30 minutes. Every 30 seconds, 1.0 ml of the slurry was injected between the bristles of the brush and the specimen. After abrasive challenge, the samples had their color and roughness reevaluated. Data were submitted to the Kruskal-Wallis test (color change) or the t-test (surface roughness). The level of significance was 5%. Results: Brushing did not significantly change the color of the composites tested in the study herein . On the other hand, the surface roughness of the composites was significantly affected by the abrasive challenge, regardless of the toothpaste used. The surface roughness change was similar for all the composites. The abrasive challenge with the toothpastes Maximum Cavity protection, Sensodyne Repair & Protect and Colgate Sensitive Pro-Relief was not able to significantly change the color of the composite resins. Nevertheless, the abrasive challenges significantly altered the surface roughness of all the evaluated composites. However, the changes in surface roughness were statistically similar in the microhybrid and nanofilled composites. (AU)

O objetivo deste estudo foi avaliar a estabilidade de cor e a rugosidade superficial de diferentes resinas compostas escovadas com dentifrícios de diferentes níveis de abrasividade. Trinta discos de cada material foram obtidos utilizando compósitos micro-híbridos (Brilliant NG e Charisma Diamond) e um nanocompósito (Filtek Z350XT). A cor inicial (CIELab) e a rugosidade superficial (microscopia confocal de varredura a laser) dos discos de resina foram avaliadas. Em seguida, 10 amostras por grupo foram escovadas com os dentifrícios Máxima Proteção Anticáries, Sensodyne Repair & Protect e Colgate Sensitive Pro-Alívio. A escovação foi realizada com uma escova elétrica com cabeça de cerdas macias, com potência e peso padronizados, durante 30 minutos. A cada 30 segundos, 1,0 ml da pasta era injetada entre as cerdas da escova e a amostra. Após o desafio abrasivo, as amostras tiveram sua cor e rugosidade reavaliadas. Os dados foram submetidos ao teste de Kruskal-Wallis (alteração de cor) ou ao teste t (rugosidade da superfície) (α=5%). A escovação não alterou significativamente a cor dos compósitos. Por outro lado, a rugosidade superficial dos compósitos foi significativamente afetada pelo desafio abrasivo, independentemente do dentifrício utilizado. A alteração da rugosidade superficial foi semelhante para todos os compósitos. O desafio abrasivo com a Máxima Proteção Anticáries, o Sensodyne Repair & Protect e o Colgate Sensitive Pro-Alívio não foi capaz de alterar significativamente a cor das resinas. Diferentemente, os desafios abrasivos alteraram significativamente a rugosidade superficial de todos os compósitos avaliados. No entanto, as mudanças na rugosidade foram estatisticamente semelhantes nos compósitos micro-híbridos e nanoparticulado. (AU)

Influence of Er,Cr:YSGG laser on root dentin submitted to erosive and/or abrasive challenges.

This study evaluated how Er,Cr:YSGG laser, associated or not with 5% fluoride varnish, influences the surface roughness and volume loss of bovine root dentin submitted to erosive and/or abrasive wear. One hundred and twenty dentin specimens were divided into the groups: without preventive treatment (WPT), 5% fluoride varnish (FV); Er,Cr:YSGG laser irradiation (L), and varnish combined with laser (FV + L). The specimens (n = 10) were subdivided into: 1 = erosion (E); 2 = abrasion (A); and 3 = erosion followed by abrasion (E + A). The erosive solution used was a soft-drink (pH = 2.42 at 4ºC) applied in 5-min cycles twice a day for 10d. Abrasive wear involved brushing for 60s with an electric brush (1,600-oscillations/s) at a load of 2.0N. Surface roughness and volume loss were evaluated using a laser scanning confocal microscope. Roughness data were submitted to one-way ANOVA and Tukey post-hoc test. For volume loss, the Kruskal-Wallis and Dunn's post-hoc tests were used (α = 5%). The lowest values of roughness were found in the control areas of all subgroups (p > 0.05). In the experimental area, the [(WPT) + (E+A)] subgroup had a significantly higher roughness (5.712 ± 0.163 µm 2 ) than the other subgroups (p < 0.05). The L and (FV + L) groups had statistically similar roughness, regardless of the type of wear. The (FV + L) group had the lowest volume loss, regardless of the type of wear performed: [(FV + L) + (E)] = 7.5%, [(FV + L) + (A) = 7.3%, and [(FV + L) + (E + A)] = 8.1%. The subgroup [(WPT) + (E + A)] had the highest volume loss (52.3%). The proposed treatments were effective in controlling dentin roughness. Laser irradiation can be an effective method to increase root dentin resistance after challenges and limit problems related to non-carious lesions.

Influence of Er, Cr: YSGG laser on root dentin submitted to erosive and/or abrasive challenges

Abstract This study evaluated how Er,Cr:YSGG laser, associated or not with 5% fluoride varnish, influences the surface roughness and volume loss of bovine root dentin submitted to erosive and/or abrasive wear. One hundred and twenty dentin specimens were divided into the groups: without preventive treatment (WPT), 5% fluoride varnish (FV); Er,Cr:YSGG laser irradiation (L), and varnish combined with laser (FV + L). The specimens (n = 10) were subdivided into: 1 = erosion (E); 2 = abrasion (A); and 3 = erosion followed by abrasion (E + A). The erosive solution used was a soft-drink (pH = 2.42 at 4ºC) applied in 5-min cycles twice a day for 10d. Abrasive wear involved brushing for 60s with an electric brush (1,600-oscillations/s) at a load of 2.0N. Surface roughness and volume loss were evaluated using a laser scanning confocal microscope. Roughness data were submitted to one-way ANOVA and Tukey post-hoc test. For volume loss, the Kruskal-Wallis and Dunn's post-hoc tests were used (α = 5%). The lowest values of roughness were found in the control areas of all subgroups (p > 0.05). In the experimental area, the [(WPT) + (E+A)] subgroup had a significantly higher roughness (5.712 ± 0.163 μm 2 ) than the other subgroups (p < 0.05). The L and (FV + L) groups had statistically similar roughness, regardless of the type of wear. The (FV + L) group had the lowest volume loss, regardless of the type of wear performed: [(FV + L) + (E)] = 7.5%, [(FV + L) + (A) = 7.3%, and [(FV + L) + (E + A)] = 8.1%. The subgroup [(WPT) + (E + A)] had the highest volume loss (52.3%). The proposed treatments were effective in controlling dentin roughness. Laser irradiation can be an effective method to increase root dentin resistance after challenges and limit problems related to non-carious lesions.

Influence of Er, Cr: Ysgg Laser Associated or not To 5% Fluoride Varnish in the Erosion Treatment of Bovine Enamel / Influência do Laser Er, Cr: Ysgg Associado ou não ao Verniz Fluoretado 5% no Tratamento da Erosão em Esmalte Bovino

The objective of this in vitro study was to evaluate the influence of the Er,Cr:YSGG laser associated or not to a desensitizing agent in the treatment of erosive lesions. Forty specimens with dimensions of 4mm x 4mm and 3mm thickness were divided into 4 groups (n = 10): G1- no treatment; G2- 5% fluoride varnish; G3- Er,Cr: YSGG; G4 - fluoride varnish + laser. The specimens were immersed in erosive drink 3 times a day for 1 minute with an average interval of 2 hours between cycles for a period of 10 days. The treatments were performed according to the groups and the surface roughness and the wear profile were analyzed by scanning confocal microscopy. The normality (Kolmogorov-Smirnov) and homogeneity (Levene's) of the tests were evaluated. After these analyzes, the surface roughness data were submitted to the statistical analysis of Variance Analysis (ANOVA). All tests adopted a significance level of 5% (α = 0.05). At the representative images of the wear profile, the morphology of bovine dental enamel in its control and eroded areas were compared and qualitatively discussed. As regard surface roughness, there was no statistically significant difference between the groups. The qualitative analysis of the loss of volume showed that all experimental groups showed significant superficial morphology differences. Considering the limitations of an in vitro study, it can be concluded that the treatments performed were not able to treat dental erosion satisfactorily, indicating the need for more treatment sessions. (AU)

O objetivo desse estudo in vitro foi avaliar a influência do laser Er,Cr:YSGG associado ou não a um agente dessensibilizante no tratamento de lesões erosivas. Foram confeccionados 40 espécimes com dimensões de 4mm x 4mm e 3mm de espessura, divididos em 4 grupos (n=10): G1- nenhum tratamento; G2- verniz fluoretado 5%; G3- aplicação do laser Er,Cr:YSGG; G4- verniz fluoretado + laser. Os espécimes foram imersos em bebida erosiva, 3 vezes por dia, durante 1 minuto, com intervalo médio de 2 horas entre os ciclos, por um período de 10 dias. Os tratamentos foram realizados de acordo com os grupos e que foram analisados a rugosidade superficial e o perfil de desgaste por meio de microscopia confocal de varredura. Avaliou-se a normalidade (Kolmogorov-Smirnov) e homogeneidade (Levene's) dos dados. Após estas análises, os dados de rugosidade superficial foram submetidos ao teste estatístico de Análise de Variância (ANOVA). Todos os testes adotaram nível de significância de 5% (α=0,05). Através da obtenção das imagens representativas do perfil desgaste, a morfologia do esmalte dental bovino em suas áreas controle e erodida foram comparadas e qualitativamente discutidas. Quanto à rugosidade superficial, não houve diferença estatisticamente significativa entre os grupos. A análise qualitativa da perda de volume mostrou que todos os grupos experimentais apresentaram diferenças significativas na morfologia superficial. Considerando as limitações de um estudo in vitro pode-se concluir que os tratamentos realizados não foram capazes de tratar a erosão dentária de forma satisfatória, indicando a necessidade de mais sessões de tratamento.

Use of Resin Infiltrate for the Treatment of White spot Lesions on Dental Enamel: Case Report / Utilização de Infiltrante Resinoso Para o Tratamento de Lesões de Mancha Branca do Esmalte Dental: Relato de Caso

Early diagnosis of white spot lesions allows non-invasive treatment to be indicated for the remineralization of active lesions. The goal was to report the clinical Protocol for the treatment of white spot lesion of a patient by the technique of resin infiltration, observing whether there is change of color on the white spot of the dental enamel after its treatment. The selected patient was 16 years old with good overall health, who featured white spot lesion of the dental enamel on tooth 13, classified as ICDAS score 2. The tooth was photographed, and its color was evaluated with the spectrophotometer in accordance with the CIELhC system. For comparison purposes, the color of tooth enamel in an area adjacent to the lesion was evaluated. The treatment of the lesion was performed with the resin infiltrate Icon (DMG, Hamburg, Germany), following the manufacturer's instructions. The color of the tooth was re-evaluated after the application of the resin infiltrate. At the end of the procedure, it was observed that the treatment of white spot lesion by resin infiltration technique reached its goal because, in addition to being minimally invasive, it was highly approved by patient and it provided the masking of the white spot lesion on the dental enamel. (AU).

O diagnóstico precoce de lesões de mancha branca permite que um tratamento não invasivo seja indicado para a remineralização das lesões ativas. O objetivo foi relatar o protocolo clínico para tratamento de lesão de mancha branca ativa de um paciente pela técnica do infiltrante resinoso, observando se existe alteração de cor da mancha branca do esmalte dental após o seu tratamento. Foi selecionada uma paciente, de 16 anos de idade, com boa saúde geral e que apresentava lesão de mancha branca no esmalte dental do dente 13, classificada pelo escore 2 do ICDAS. O dente foi fotografado e sua cor foi avaliada com o espectrofotômetro de acordo com o sistema CIELhC. Para fins de comparação, foi avaliada a cor do esmalte dental em uma área adjacente à lesão. O tratamento da lesão foi realizado com a resina infiltrante Icon (DMG, Hamburgo, Alemanha), seguindo as recomendações do fabricante. A cor do dente foi reavaliada após a aplicação do infiltrante. Ao final do procedimento, observou-se que o tratamento da lesão de mancha branca pela técnica da resina infiltrante atingiu seu objetivo pois, além de ter sido minimamente invasiva, foi bem avaliada pela paciente e proporcionou o mascaramento da lesão de mancha branca do esmalte dental. (AU).

Influence of Er,Cr:YSGG laser, associated or not to desensitizing agents, in the prevention of acid erosion in bovine root dentin.

This in vitro study evaluated the influence of the Er,Cr:YSGG laser, associated or not to desensitizing agents, in the prevention of acid erosion in bovine root dentin. Eighty dentin specimens were selected and divided into eight groups (n = 10): G1: negative control; G2: positive control (5% fluoride varnish-FV); G3: Er,Cr:YSGG laser; G4: FV + laser; G5: 3% potassium oxalate; G6: 3% potassium oxalate + laser; G7: biphasic calcium silicate/phosphate gel (gel); G8: gel + laser. Laser parameters: 0.5 W, 6.25 J/cm2 at 1-mm distance. The erosive drink used was a cola soft-drink (pH = 2.42 at 4 °C), lasting 5 min, twice a day, with 6-h intervals between the challenges, during 14 days. Kolmogorov-Smirnov and Levene's tests were satisfied. The surface roughness data were submitted to ANOVA and Tukey post hoc tests. For the wear profile, Kruskal-Wallis and Dunn post hoc tests were used. Afterwards, the Spearman correlation test was performed. All statistical tests assumed a significance level of 5% (α = 0.05). G1 presented the highest surface roughness value after the erosive challenge (3.586 µm2 ± 0.205 µm2) and the G7 presented the lowest surface roughness value after the erosive challenge (1.071 µm2 ± 0.180 µm2). For the lost volume, G4 presented the lowest percentage (9.7% ± 0.9%), while G1 had the highest percentage (41.8% ± 2.5%), both with p < 0.05. There was a weak correlation between the response variables (ρ = 0.33). All groups presented lower values of surface roughness and loss of volume when compared to the negative control group. For the surface roughness, the biphasic calcium silicate/phosphate gel presented the best result. For volume loss, the 5% fluoride varnish + Er,Cr:YSGG laser showed the best results compared to the other groups.

Influence of Remineralizing Dentifrice in the Treatment of Erosive Enamel Lesions / Influência de Dentifrício Remineralizante no Tratamento de Lesões Erosivas em Esmalte

The objective of this in vitro study was to evaluate the influence of different remineralizing agents in the treatment of enamel erosive lesions. Specimens of 4mmx4mm and 3mm thickness were made from the buccal surface of bovine incisors (n=10) and randomly divided into 4 groups. G1 = application of the remineralizing dentifrice, G2 = application of the remineralizing agent, G3 = remineralizing dentifrice + remineralizing agente, G4 = application of fluoride varnish (positive control), G5 = no treatment Specimens were immersed in refrigerant solution during a period of 10 days. The surface roughness was analyzed by means of confocal laser scanning microscopy. The data were analyzed for homogeneity (Levene's) and normality (Kolmogorov-Smirnov). Parametric tests with analysis of variance were performed on two criteria: time factor and treatment factor, and Tukey post-test for differentiation of means. All tests were statistically significant at 5% (α = 0.05). The results showed statistically significant difference, demonstrating the reduction of surface roughness after the first treatment (G3) and the other groups (G1, G2 and G4) only after the second treatment. It was concluded that the use of dentifrice composed of calcium silicate and sodium phosphate influenced the roughness of the eroded tooth enamel of the bovine tooth. (AU)

O objetivo deste trabalho in vitro foi avaliar a influência de diferentes agentes remineralizantes no tratamento de lesões erosivas em esmalte. Foram confeccionados espécimes de 4mmx4mm e 3 mm de espessura a partir da superfície vestibular de incisivos bovinos (n=10) e divididos aleatoriamente em 4 grupos. G1=aplicação do dentifrício remineralizante, G2= aplicação do agente potencializador remineralizante, G3= dentifrício remineralizante + agente potencializador remineralizante, G4=aplicação de verniz fluoretado (controle positivo), G5=nenhum tratamento (controle negativo). Os espécimes foram imersos em refrigerante durante um período de 10 dias. A rugosidade superficial foi analisada por meio de microscopia confocal de varredura a laser. Os dados foram analisados quanto à homogeneidade (Levene's) e normalidade (Kolmogorov- Smirnov). Foram realizados testes paramétricos com análise de variância a dois critérios: fator tempo e fator tratamento, e pós-teste de Tukey para diferenciação das médias. Todos os testes estatísticos tiveram nível de significância de 5% (α=0,05). Os resultados obtidos mostraram diferenças estatisticamente significantes, demonstrando a redução da rugosidade da superfície do esmalte logo após o primeiro tratamento (G3) e para os demais grupos (G1, G2 e G4) somente após o segundo tratamento. Concluiu-se que a utilização de dentifrício composto por silicato de cálcio e fosfato de sódio influenciou na rugosidade do esmalte erodido do dente bovino. (AU).