Impact of Molar Incisor Hypomineralization on Oral Health-Related Quality of Life in Brazilian Schoolchildren Aged 8 to 10 Years

ABSTRACT Objective: To assess the impact of Molar Incisor Hypomineralization (MIH) and confounding factors on oral health-related quality of life (OHRQoL) according to the perception of 8 to 10-year-old children and their parents/caregivers. Material and Methods: A cross-sectional study including 403 students aged 8-10 years was carried out, in which OHRQoL was measured using the Child Perceptions Questionnaire administered to both children and parents/caregivers. The diagnosis of MIH was performed according to the previously proposed index. Dental caries experience, malocclusion, and sociodemographic factors were evaluated as confounders. Cluster analysis and Poisson regression with robust variance (p<0.05) were performed. Results: The prevalence of MIH was 13.4%. Parents/caregivers of children with MIH in incisors showed a higher impact prevalence in the emotional well-being domain (PR=1.92; 95%CI=1.16-3.19). Children with hypoplasia had a higher prevalence of negative impact on OHRQoL in the oral symptoms domain (PR=1.51; 95%CI=1.03-2.23). According to the perception of parents/caregivers, dental caries experience had a negative impact on the quality of life of students in the emotional well-being domain (PR=4.19; 95%CI=1.06-16.49) and in the total questionnaire score (PR=3.21; 95%CI=1.06-9.71). Conclusion: According to the perception of parents/caregivers, children with MIH in incisors showed a greater impact on OHRQoL. Additionally, the presence of hypoplasia affected the self-perception of OHRQoL in children, and caries experience influenced the OHRQoL of children, as perceived by parents/caregivers.

Assessment of Efficiency of Bioactive Glass, Self-Assembling Peptide, and Ozone Remineralising Agents on Artificial Carious Lesion

ABSTRACT Objective: To assess the efficacy of bioactive glass, self-assembling peptide, and ozone-remineralizing agents on the artificial carious lesion. Material and Methods: On the extracted 60 premolar teeth, an artificial carious lesion/demineralization was created. Later, the remineralization of demineralized teeth was done with respective remineralizing agents (Group A: Calcium sodium phosphosilicate (bioactive glass), Group B: Self-assembling peptide, Group C: Ozone remineralizing agents and Group D (Control): De ionized water. The degree of demineralization and remineralization were evaluated using the Vickers Hardness Number. Results: There was a decrease in microhardness from baseline to demineralization in all the groups, and this reduction was found to be statistically considerable. After the remineralization of demineralized samples with respective remineralizing agents, there was an increase in microhardness of 312.38, 276.67, and 254.42 in groups A, B, and C, respectively. In contrast, in Group D, there were no changes. Conclusion: Bioactive glass and self-assembling peptides had higher remineralizing capacities, which can be used to treat early carious lesions.

Avaliação dos Efeitos da Remoção da Resina Residual e do Polimento na Superfície do Esmalte após Descolagem do Braquete / Evaluation of the Effects of Residual Resin Removal and Polishing on the Enamel Surface after Bracket Debonding

Considerando o uso de brocas para remoção da resina residual após descolagem do braquete e a possibilidade de injúrias à superfície do esmalte após o uso dessas brocas, este trabalho teve como objetivo realizar um estudo experimental, para avaliar a variação do aspecto superficial do esmalte de forma qualitativa, por meio da avaliação com imagens topográficas do esmalte dentário, utilizando-se a Microscopia Eletrônica de Varredura (MEV), a qual permitiu ilustrar e avaliar a superfície do esmalte após a fase de polimento final, realizada por dois métodos: taça de borracha ou escova Robinson. Foram utilizados 25 dentes pré-molares humanos, obtidos a partir de exodontias em pacientes que procuraram voluntariamente o curso de Residência em Cirurgia da Clínica Odontológica Universitária da Universidade Estadual de Londrina. Os dentes foram divididos em quatro grupos: A, B, C e D, contendo 6 dentes cada, de acordo com as brocas utilizadas para a remoção do remanescente adesivo e o polimento escolhido, além de um dente como "controle". Foi avaliada a rugosidade superficial do esmalte após a remoção da resina e a superfície do esmalte após o polimento com as duas opções apresentadas. Os resultados mostraram que, por observação e inspeção, as brocas removeram a resina residual de todos os dentes, porém, causaram riscos e ranhuras, como evidenciado nas imagens em MEV. Concluiu-se que não houve diferença estatística entre os métodos de polimento e que ambos foram importantes para a redução das marcas abrasivas, proporcionando uma superfície mais lisa do esmalte.

Considering the use of specific burs to remove residual resin after bracket debonding and the possibility of injuries to the dental enamel after using these burs, this study aimed to verify the variation in the enamel surface appearance in a qualitative way and evaluation with topographic images of the dental enamel. The use of Scanning Electron Microscopy (SEM) allowed to illustrate and evaluate the enamel surface after the final polishing phase using two methods: rubber cup or Robinson brush. Twenty-five human premolar teeth were obtained from extractions in patients who voluntarily sought the Oral Maxillofacial Surgery Residency at the Dental School from the State University of Londrina; the teeth were divided into four groups A, B, C and D containing 6 teeth each according to the burs used to remove the remaining adhesive and the chosen polishing, in addition to one tooth as a "control". Dental enamel surface roughness was evaluated after resin removal and enamel surface after polishing with the two methods presented. The results showed that by observation and inspection, the burs removed residual resin from all teeth, however, caused scratches and grooves as evidenced in the SEM images. Based on the results, there was no statistical difference between the polishing methods, and both were important for the reduction of abrasive marks and provided a smoother enamel surface.

Toothbrushing effects on the surface roughness and cement volume loss of bonded enamel-ceramic interface

Abstract This study evaluated the effect of toothbrushing on enamel-cementing material-ceramic bonded interfaces, using different cementing materials. Materials and Methods: Thirty enamel and thirty ceramic blocks were bonded with cementing materials to produce the samples that were bonded with three types of cementing materials: 1- RelyX Ultimate resin cement (REXU), 2- RelyX Unicem 2 self-adhesive resin cement (REU2) and 3- heated Z100 restorative composite (60°C). Bonded interfaces of the samples were toothbrushed and the surfaces of the 3 cementing materials were evaluated for roughness (RG, in µm), roughness profile (RP, in µm), and volume loss (VL, in µm3) (baseline and after 20,000 and 60,000 toothbrushing cycles). Data were evaluated by Generalized Linear Analysis (two factors: "material" and "toothbrushing cycle") and Bonferroni test (α=0.05). Results: REXU and Z100 exhibited lower RG than that presented by REU2, except after 60,000 toothbrushing cycles when only Z100 differed from REU2. The increase in toothbrushing cycles increased the RG and RP for all materials. REU2 also showed higher RP than those showed by REXU and Z100 when it was analyzed regarding the enamel. The VL of Z100 was the lowest with 20,000 toothbrushing cycles, regarding the enamel and ceramic. For 60,000 cycles, REXU showed the lowest VL regarding the ceramic, and REU2 had the highest VL regarding the enamel and ceramic. Conclusion: In general, REXU and Z100 showed the best results regarding the evaluations performed and the REU2 exhibited the highest RG, RP, and VL.

Resumo Este estudo avaliou o efeito da escovação nas interfaces de união esmalte-material cimentante-cerâmica, utilizando diferentes materiais cimentantes. Materiais e Métodos: Trinta esmaltes e trinta blocos cerâmicos foram unidos com materiais de cimentação para produzir as amostras que foram unidas com três tipos de materiais de cimentação: 1- cimento resinoso RelyX Ultimate (REXU), 2- cimento resinoso autoadesivo RelyX Unicem 2 (REU2) e 3-compósito restaurador aquecido Z100 (60°C). As interfaces coladas das amostras foram escovadas e as superfícies dos 3 materiais cimentantes foram avaliadas quanto à rugosidade (RG, em µm), perfil de rugosidade (RP, em µm) e perda de volume (VL, em µm3) (baseline e após 20.000 e 60.000 ciclos de escovação). Os dados foram avaliados por Análise Linear Generalizada (dois fatores: "material" e "ciclo de escovação") e teste de Bonferroni (α=0,05). Resultados: REXU e Z100 apresentaram menor RG do que REU2, exceto após 60.000 ciclos de escovação, quando Z100 diferiu apenas de REU2. O aumento dos ciclos de escovação aumentou o RG e RP para todos os materiais. O REU2 também apresentou PR maior que o REXU e Z100, quando analisado em relação ao esmalte. O VL de Z100 foi o menor com 20.000 ciclos de escovação em relação ao esmalte e cerâmica. Para 60.000 ciclos, o REXU apresentou o menor VL em relação à cerâmica e o REU2 o maior VL em relação ao esmalte e à cerâmica. Conclusão: De maneira geral, REXU e Z100 apresentaram os melhores resultados nas avaliações realizadas e o REU2 apresentou os maiores RG, RP e VL..

Efficacy of ClinproTMXT Varnish surrounding brackets on the enamel surface of white spot lesion

Abstract Orthodontics patients usual develop demineralization and present cavity caries lesions after six months. Minimally invasive procedures have been the goal in modern dental practice. The aim of this study was to evaluate the effect of ClinproTMXT Varnish, on the enamel surface roughness and severity of white spot lesions. Twenty premolars were submitted to bond brackets and experimental induction of demineralization and randomly divided into 2 groups: GI - fluoride varnish (Colgate Duraphat®); GII - Ionomeric Sealant (ClinproTMXT Varnish). The treatment was applied around the brackets. The surface roughness of specimens was analyzed, before treatment and 12 weeks after treatment by laser confocal microscopy, and the severity of the white spot lesion was by laser fluorescence device. The data were analyzed by non-parametric Wilcoxon and Mann-Whitney Test, at 5% significance, roughness percentage reduction was performed. The severity of demineralization decreased in both, GI (p = 0.005) and GII (p = 0.019). Enamel superficial roughness levels decreased in GI and GII. As well as the roughness percentage, being more expressive in the ClinproTMXT Varnish group (85,09%). Colgate Duraphat® or Clinpro™ XT Varnish reduced the severity of the demineralization and decreased the superficial roughness on the enamel. The Clinpro™ XT Varnish was superior to superficial roughness on enamel.

Resumo Pacientes ortodônticos geralmente desenvolvem desmineralização e apresentam lesões de cárie após seis meses de tratamento. Procedimentos minimamente invasivos têm sido o objetivo na prática odontológica moderna. O objetivo deste estudo foi avaliar o efeito do ClinproTM XT selante ionomérico, ao redor do bráquete, com relação a rugosidade superficial do esmalte e a severidade da lesão induzida. Vinte pré-molares foram submetidos a colagem de bráquetes e indução experimental de desmineralização e divididos aleatoriamente em 2 grupos: GI - verniz fluoretado (Colgate Duraphat®); GII - Selante Ionomérico (ClinproTM XT). O tratamento foi aplicado ao redor dos bráquetes. A rugosidade da superfície dos espécimes foi analisada, antes do tratamento e 12 semanas após o tratamento por microscopia confocal a laser e severidade da lesão de mancha branca por dispositivo de fluorescência a laser. Os dados foram analisados pelo teste não paramétrico de Wilcoxon e Mann-Whitney, a 5% de significância. A taxa de redução da lesão foi calculada. A severidade da desmineralização diminuiu tanto no GI (p = 0,005) quanto no GII (p = 0,019). Os níveis de rugosidade superficial do esmalte diminuíram no GI e GII, assim como o percentual de rugosidade, sendo mais expressivo no grupo ClinproTMXT (85,09%). Colgate Duraphat® e Clinpro™ XT reduziram a severidade da desmineralização e diminuíram a rugosidade superficial do esmalte. O selante ionomérico Clinpro™ XT foi superior na redução percentual de rugosidade.

Dentifrícios branqueadores contendo Blue covarine: revisão de literatura / Bleaching dentifrices containing "Blue covarine" literature review

Introdução: O efeito branqueador dos dentifrícios contendo Blue covarine é fundamentado no seu mecanismo de ação, caracterizado pela sua deposição na superfície dentária, alterando a percepção da cor. Objetivo: Revisar a literatura e buscar evidência científica sobre o efeito branqueador do Blue Covarine em tecidos mineralizados e materiais restauradores estéticos. Materiais e métodos: Para a revisão da literatura foram feitas buscas nas bases de dados PubMed, LILACS, BBO, SciELO e MEDLINE para identificar estudos clínicos e laboratoriais que avaliassem a ação branqueadora do agente óptico Blue covarine. Como estratégia de busca foram utilizados os descritores "Blue covarine", "Blue covarine e pasta de dentes", "Blue covarine and toothpaste", "Blue covarine e dentifrícios", "Blue covarine and dentifrices", "Blue covarine e dentifrícios branqueadores", "Blue covarine and whitening dentifrices", "Blue covarine e dentifrícios clareadores", "Blue covarine and bleaching dentifrices", "Blue covarine e pasta de dentes branqueadoras", "Blue covarine and whitening toothpaste", "Blue covarine e pasta de dentes clareadoras", "Blue covarine and bleaching toothpaste". Resultados: Dois pesquisadores selecionaram e analisaram criticamente 31 artigos, sendo 2 revisões da literatura, 4 estudos clínicos e 25 estudos laboratoriais. Divergências quanto ao desenho de estudo, métodos, amostra, critérios clínicos e parâmetros laboratoriais foram observados, além de conflitos de interesse. Conclusão: O Blue Covarine presente nos dentifrícios branqueadores parece ser efetivo na promoção do branqueamento dentário apenas quando associado aos agentes abrasivos presentes nas formulações, evidenciando que ensaios clínicos e laboratoriais, com metodologias semelhantes, são necessários para se obter evidência científica conclusiva sobre o efeito deste agente branqueador.(AU)

Introduction: The whitening effect of dentifrices containing Blue Covarine is based on its mechanism of action, characterized by its deposition on the tooth surface, altering the perception of color. Objective: To review the literature and seek scientific evidence on the whitening effect of Blue Covarine on mineralized tissues and aesthetic restorative materials. Materials and methods: For the literature review, searches were carried out in the PubMed, LILACS, BBO, SciELO and MEDLINE databases, in order to identify clinical and laboratory studies that evaluated the whitening action of the optical agent Blue Covarine. As a search strategy, the descriptors "Blue Covarine", "Blue Covarine and toothpaste", "Blue Covarine and dentifrices", "Blue Covarine and whitening dentifrices", "Blue Covarine and bleaching dentifrices", "Blue Covarine and whitening toothpaste", "Blue Covarine and bleaching toothpaste". Results: Two researchers selected and critically analyzed 31 articles, including 2 literature reviews, 4 clinical studies and 25 laboratory studies. Differences in study design, methods, sample, clinical criteria and laboratory parameters were observed, in addition to conflicts of interest. Conclusion: Blue Covarine present in whitening dentifrices seems to be effective in promoting dental whitening only when associated with abrasive agents present in the formulations, showing that clinical and laboratory tests, with similar methodologies, are necessary to obtain conclusive scientific evidence on the effect of this bleaching agent.(AU)

Use of enamel matrix- derived proteins combined with bone graft for the treatment of intrabony defects: overview of reviews (FRISBEE review) / Uso de proteínas derivadas de la matriz del esmalte combinado con injerto óseo para el tratamiento de defectos intraóseos: resumen estructurado de revisiones sistemáticas (revisión FRISBEE)

Introduction: The use of enamel matrix-derived proteins (EMD) has increased in recent years due to their tissue-inducing properties that support periodontal regeneration. This study is an overview of systematic reviews with FRISBEE methodology on the use of EMD alone or combined with autologous bone graft materials (BGM) in the treatment of intrabony defects. Materials and Methods: A systematic search in the Epistemonikos database was performed. RevMan 5.3 and GRADEpro were used for data analysis and presentation Results: Four systematic reviews and two clinical trials were identified. All studies analysed change in probing depth, clinical attachment level, gingival margin level and bone defect depth (all changes in favour of EMD+BGM groups: mean difference (MD): 0.37 mm more, MD: 0.7 mm more, MD: 0.3 mm less, MD: 0.75 more, respectively). Conclusions: Adding autologous bone graft to EMD to treat intrabony defects showed better results, but not a relevant clinical difference compared to the use of EMD alone.

Introducción: El uso de proteínas derivadas de la matriz del esmalte (EMD) ha aumentado en los últimos años debido a sus propiedades inductoras de tejidos que apoyan la regeneración periodontal. Este estudio es una revisión sistemática de revisiones sistemáticas utilizando metodología FRISBEE sobre el uso de EMD solo o combinado con materiales injerto óseo autólogo (BGM) en el tratamiento de defectos intraóseos. Materiales y Métodos: Se realizó una búsqueda sistemática en la base de datos Epistemonikos. Se utilizaron RevMan 5.3 y GRADEpro para el análisis y la presentación de los datos. Resultados: Se identificaron cuatro revisiones sistemáticas y dos ensayos clínicos. Todos los estudios analizaron el cambio en la profundidad de sondaje, el nivel de inserción clínica, el nivel del margen gingival y la profundidad del defecto óseo (todos los cambios a favor de los grupos EMD+BGM: MD: 0,37 mm más, media de diferencia (MD): 0,7 mm más, MD: 0,3 mm menos, MD: 0,75 más, respectivamente). Conclusión: La adición de injerto óseo autólogo a la EMD para tratar defectos intraóseos mostró mejores resultados, pero no una diferencia clínica relevante en comparación con el uso de la EMD sola.

Effect of experimental bleaching gels with polymers Natrosol and Aristoflex on the enamel surface properties

Abstract Natrosol and Aristoflex® AVC polymers are widely applied in the cosmetic industry and have recently been applied as a thickener option in the composition of dental bleaching gels, with the purpose to reduce the adverse effects on enamel mineral components. The aim of this study was to evaluate the color variation (ΔE* ab, ΔE00, ∆WID), surface roughness (Ra), and mineral content quantification (Raman Spectroscopy) of dental enamel after bleaching treatment with experimental gel-based on 10% carbamide peroxide (CP), containing Carbopol, Natrosol, and Aristoflex® AVC. Sixty bovine teeth were randomly divided into 6 groups (n=10): Negative Control (NC) - no treatment; Positive Control (PC) - Whiteness Perfect 10% - FGM; CP with Carbopol (CPc); CP with Natrosol (CPn); CP with Aristoflex® AVC (CPa); NCP - no thickener. Data were analyzed, and generalized linear models (∆WID -T0 x T1) were used for repeated measurements in time for Ra and with a study factor for ΔE* ab and ΔE00. For the evaluation of the mineral content, data were submitted to one-way ANOVA and Tukey tests. For enamel topographic surface analysis the Scanning Electron Microscope (SEM) was performed. A significance level of 5% was considered. ΔE* ab and ΔE00 were significantly higher for CPc, CPn, CPa, and NCP groups. (∆WID) showed a significantly lower mean than the other groups for NC in T1. After bleaching (4-hour daily application for 14 days), Ra was higher in the CPc, CPn, and PC groups. For CPa, Ra was not altered. No significant difference was found in the quantification of mineral content. CPa preserved the surface smoothness more effectively. Aristoflex® AVC is a viable option for application as a thickener in dental bleaching gels, presenting satisfactory performance, and maintaining the whitening efficacy of the gel, with the advantage of preserving the surface roughness of tooth enamel without significant loss of mineral content.

Resumo Os polímeros Natrosol e Aristoflex® AVC são amplamente utilizados na indústria cosmética e foram recentemente aplicados como uma opção de espessante na composição de géis de clareamento dental, com o objetivo de reduzir os efeitos adversos sobre os componentes minerais do esmalte. O objetivo deste estudo foi avaliar a variação de cor (ΔE*ab, ΔE00, ∆WID), rugosidade da superfície (Ra), e quantificação do conteúdo mineral (Raman Spectroscopy) do esmalte dentário após clareamento dental com gel experimental baseado em 10% de peróxido de carbamida (CP), contendo Carbopol, Natrosol e Aristoflex® AVC. Sessenta dentes bovinos foram divididos aleatoriamente em 6 grupos (n=10): Controle Negativo (CN) - sem tratamento; Controle Positivo (CP) - Brancura Perfeita 10% - FGM; CP com Carbopol (CPc); CP com Natrosol (CPn); CP com Aristoflex® AVC (CPa); NCP - sem espessante. Os dados foram analisados e modelos lineares generalizados (∆WID -T0 x T1) foram usados para medições repetidas no tempo para Ra e com um fator de estudo para ΔE*ab e ΔE00. Para a avaliação do conteúdo mineral, os dados foram submetidos a testes unidirecionais de ANOVA e Tukey. Para a análise da superfície topográfica do esmalte, o Microscópio Eletrônico de Varredura (SEM) foi realizado. Um nível de significância de 5% foi considerado. ΔE*ab e ΔE00 foram significativamente maiores para os grupos CPc, CPn, CPa e NCP. (∆WID) mostrou uma média significativamente menor do que os outros grupos para NC em T1. Após o clareamento (aplicação diária de 4 horas por 14 dias), Ra foi maior nos grupos CPc, CPn e PC. Para CPa, Ra não foi alterado. Nenhuma diferença significativa foi encontrada na quantificação do conteúdo mineral. O CPa preservou a suavidade da superfície de forma mais eficaz. Aristoflex® AVC é uma opção viável para aplicação como espessante em géis de clareamento dental, apresentando desempenho satisfatório e mantendo a eficácia clareadora do gel, com a vantagem de preservar a rugosidade da superfície do esmalte dentário sem perda significativa de conteúdo mineral.

Do patients with molar incisor hypomineralization have more dental anxiety and behavior management problems? A systematic review with meta-analysis

Abstract This systematic review evaluated the available evidence on whether children with molar incisor hypomineralization (MIH) have more dental fear and anxiety (DFA) and dental behavior management problems (DBMPs) than those without MIH (Prospero CDR42020203851). Unrestricted searches were performed in PubMed, Scopus, Web of Science, Lilacs, BBO, Embase, Cochrane Library, APA PsycINFO, Open Grey, and Google Scholar. Observational studies evaluating DFA and/or DBMPs in patients with and without MIH were eligible. Reviews, case reports, interventional studies, and those based on questionnaires to dentists were excluded. The methodological quality assessment was based on the Newcastle-Ottawa Scale. Random-effects meta-analyses were conducted to synthesize data on DFA. The certainty of evidence was performed according to GRADE. Seven studies that evaluated a total of 3,805 patients were included. All of them presented methodological issues, mainly in the comparability domain. Most studies observed no significant difference in DFA between children with and without MIH. The meta-analysis did not show a significant effect of MIH on the standardized units for the DFA scores (SMD = 0.03; 95%CI: -0.06-0.12; p = 0.53; I2 = 0%). Synthesis including only the results for severe cases of MIH also did not show a significant effect of the condition on DFA scores (MD = 8.68; 95%CI: -8.64-26.00; p = 0.33; I2 = 93%). Two articles found DBMPs were significantly more frequent in patients with MIH. The overall certainty of evidence was very low for both outcomes assessed. The current evidence suggests no difference in DFA between children with and without MIH; DBMPs are more common in patients with MIH. This information should be viewed with caution because of the very low quality evidence obtained.

Susceptibility of fluorotic enamel to dental erosion-abrasion

Abstract Dental hard tissue conditions can be of pre- or post-eruptive nature, such as enamel fluorosis and erosive tooth wear (ETW), respectively. Dental enamel fluorosis is caused by the chronic and excessive intake of fluoride during enamel development, leading to increased fluoride concentration and increased porosity. ETW has become a common clinical condition and often impairs dental function and aesthetics. This in vitro study tested the hypothesis that fluorotic enamel presents different susceptibility to dental erosion-abrasion. It consisted of a 3×3×2 factorial design, considering a) fluorosis severity: sound (TF0), mild (TF1-2), moderate (TF3-4); b) abrasive challenge: low, medium, and high; and c) erosive challenge: yes or no. A total of 144 human teeth were selected according to the three fluorosis severity levels (n=48), and subdivided into six groups (n = 8) generated by the association of the different erosive and abrasive challenges. Enamel blocks (4×4 mm) were prepared from each tooth and their natural enamel surfaces subjected to an erosion-abrasion cycling model. After cycling, the depth of the lesions in enamel was assessed by profilometry. ANOVA showed that the three-way and two-way interactions among the factors were not significant (p > 0.20). Enamel fluorosis level (p=0.638) and abrasion level (p = 0.390) had no significant effect on lesion depth. Acid exposure caused significantly more enamel surface loss than water (p < 0.001). Considering the limitations of this in vitro study, fluorosis did not affect the susceptibility of enamel to dental erosion-abrasion.

Effect of fluoride gels with nano-sized sodium trimetaphosphate on the in vitro remineralization of caries lesions

Abstract Objective To evaluate the effects of fluoride (F) gels supplemented with micrometric or nano-sized sodium trimetaphosphate (TMPmicro and TMPnano, respectively) on the in vitro remineralization of caries-like lesions. Methodology Bovine enamel subsurface lesions (n=168) were selected according to their surface hardness (SH) and randomly divided into seven groups (n=24/group): Placebo (without F/TMP), 4,500 ppm F (4500F), 4500F + 2.5% TMPnano (2.5% Nano), 4500F + 5% TMPnano (5% Nano), 4500F + 5% TMPmicro (5% Micro), 9,000 ppm F (9000F), and 12,300 ppm F (Acid gel). The gels were applied in a thin layer for one minute. Half of the blocks were subjected to pH cycling for six days, whereas the remaining specimens were used for loosely- (calcium fluoride; CaF2) and firmly-bound (fluorapatite; FA) fluoride analysis. The percentage of surface hardness recovery (%SHR), area of subsurface lesion (ΔKHN), CaF2, FA, calcium (Ca), and phosphorus (P) on/in enamel were determined. Data (log10-transformed) were subjected to ANOVA and the Student-Newman-Keuls' test (p<0.05). Results We observed a dose-response relation between F concentrations in the gels without TMP for %SHR and ΔKHN. The 2.5% Nano and 5% Micro reached similar %SHR when compared with 9000F and Acid gels. For ΔKHN, Placebo and 5% Nano gels had the highest values, and 5% Micro, 2.5% Nano, 9000F, and Acid gels, the lowest. All groups had similar retained CaF2 values, except for Placebo and Acid gel. We verified observed an increase in Ca concentrations in nano-sized TMP groups. Regarding P, TMP groups showed similar formation and retention to 9000F and Acid. Conclusion Adding 2.5% nano-sized or 5% micrometric TMP to low-fluoride gels lead to enhanced in vitro remineralization of artificial caries lesions.

Rehabilitation Treatment in Pediatric Patients with Molar Incisor Hypomineralization: A Scoping Review

ABSTRACT Objective: To identify the available evidence on the different treatment types for the rehabilitation of MIH-affected teeth in children. Material and Methods: A search was carried out in Pubmed, Cochrane Library, Epistemonikos, Lilacs and Google Scholar. Observational studies published until June 2022 were included. Two reviewers independently screened studies and extracted data. Results: 1593 studies were screened and a total of 38 articles were included, which were mainly case reports published in Brazil. Most included studies concluded that the evaluated treatment was "beneficial" or "probably beneficial". Reported treatments included: glass ionomer cements (GIC), composite resin restorations, preformed metal crowns, laboratory fabricated crowns, microabrasion management of incisors and resin infiltration. Conclusion: Successful treatment options have been identified, such as GIC as a provisional restoration for severe cases and for uncooperative children; restorations with composite, indirect restorations, or preformed metal crowns also seem suitable treatment options for young patients diagnosed with MIH. There is still little evidence to support an approach for anterior teeth affected by MIH.

Use of Images and Clinical Experience to Calibrate Dental Surgeons for the Diagnosis of Molar Incisor Hypomineralization

ABSTRACT Objective: To evaluate an imaging protocol for use as a diagnostic and calibration tool for dentists before and after practical activity. Material and Methods: Thirty photos of children's teeth with or without changes in dental enamel were selected and evaluated by a group of experienced dentists previously calibrated to establish the diagnosis defined as the gold standard. After instructions, the images were shown to a group of postgraduate dentists for free identification of dental changes. Subsequently, a lecture on molar incisor hypomineralization (MIH) was carried out, and, at 14 days and all calibration was performed using the criteria previously. The retest was performed at 28 days. After experience in clinical activity in the following two weeks, the post-test was performed at 49 days. Data were analyzed using Cohen's kappa coefficient. Results: Theoretical learning on the subject showed low inter-examiner agreement when the diagnosis of defects was made from images obtained from intraoral photographs. After clinical practice, there was greater intra-examiner agreement. After theoretical training, dentists started to identify different types of enamel alteration, although with low agreement between them. Conclusion: Clinical experience in theoretical and imaging training favored the identification of defects. However, it is necessary to improve the protocol to establish a reliable and viable diagnostic method for calibration in MIH.

Effect of an aqueous 4% titanium tetrafluoride solution on preventing caries in orthodontic patients: a controlled clinical trial

ABSTRACT Introduction: Titanium tetrafluoride (TiF4) is a fluoride compound that, when is applied over enamel, promotes a protection against demineralization through a titanium dioxide (TiO2) acid-resistant coat. Objectives: This study sought to verify the hypothesis that a single application of 4% TiF4 increases the resistance of enamel to dental demineralization in orthodontic patients. Materials and Methods: This controlled clinical trial followed CONSORT guidelines and investigated the prevention of enamel demineralization, fluoride retention, and the presence of a Ti layer after TiF4 application on banded teeth exposed to clinical cariogenic biofilm. Forty premolars were divided into a control group (CG; n = 20) and a test group (TG; n = 20). Teeth from both groups received prophylaxis and orthodontic bands with a cariogenic locus. In the TG, all teeth additionally underwent aqueous 4% TiF4 solution application after prophylaxis before being banded. After one month, teeth from both groups were extracted and prepared to assess the microhardness, fluoride retention, and evaluation of the Ti coating over the enamel surface. All data were analyzed with a paired Student's t-test (p<0.05). Results: Enamel microhardness and fluoride uptake were higher in TG than in CG, while the Ti layer could be seen over TG teeth that received TiF4 application. Conclusion: Under clinical circumstances, the 4% aqueous TiF4 solution was effective in preventing enamel mineral loss through increasing the enamel resistance to dental demineralization, enhancing its microhardness and fluoride uptake, and forming a Ti coat.

RESUMO Introdução: O tetrafluoreto de titânio (TiF4) é um composto fluoretado que, quando aplicado sobre o esmalte dentário, promove uma proteção contra desmineralização, por meio da formação de uma camada ácido-resistente de dióxido de titânio (TiO2). Objetivos: O presente estudo buscou verificar a hipótese de que uma única aplicação de TiF4 a 4% aumenta a resistência do esmalte dentário à desmineralização, em pacientes ortodônticos. Material e Métodos: Esse ensaio clínico controlado seguiu as diretrizes do CONSORT e investigou a prevenção da desmineralização do esmalte, retenção de flúor e a presença de uma camada de titânio após a aplicação do TiF4 em dentes bandados expostos ao biofilme cariogênico clínico. Quarenta pré-molares foram divididos em dois grupos: controle (GC; n = 20) e teste (GT; n = 20). Dentes de ambos os grupos receberam profilaxia e bandas ortodônticas com nicho cariogênico. No GT, todos os dentes também foram submetidos a aplicação de solução aquosa de TiF4 4 após profilaxia, antes de serem bandados. Após um mês, os dentes de ambos os grupos foram extraídos e preparados para avaliar a microdureza, retenção de flúor e avaliação da camada de titânio sobre a superfície do esmalte. Todos os dados foram analisados pelo teste t pareado (p<0,05). Resultados: A microdureza do esmalte e a absorção de flúor foram mais elevadas no GT do que no GC, enquanto uma camada de titânio pôde ser observada sobre os dentes do GT, que receberam aplicação TiF4. Conclusão: Em circunstâncias clínicas, a solução de TiF4 a 4% foi eficaz na prevenção da perda mineral do esmalte, por meio do aumento da resistência à desmineralização dentária, aumentando sua microdureza e absorção de flúor, e formando uma camada protetora de titânio.

In vitro effect of low-fluoride toothpaste supplemented with sodium trimetaphosphate, xylitol, and erythritol on enamel demineralization

Abstract Regular use of toothpaste with fluoride (F) concentrations of ≥ 1000 ppm has been shown to contribute to reducing caries increment. However, when used by children during the period of dental development, it can lead to dental fluorosis. Objective: In this study, we aimed to evaluate the in vitro effect of a toothpaste formulation with reduced fluoride (F) concentration (200 ppm) supplemented with sodium trimetaphosphate (TMP: 0.2%), Xylitol (X:16%), and Erythritol (E: 4%) on dental enamel demineralization. Methodology: Bovine enamel blocks were selected according to initial surface hardness (SHi) and then divided into seven experimental toothpaste groups (n=12). These groups included 1) no F-TMP-X-E (Placebo); 2) 16% Xylitol and 4% Erythritol (X-E); 3) 16% Xylitol, 4% Erythritol and 0.2%TMP (X-E-TMP); 4) 200 ppm F (no X-E-TMP: (200F)); 5) 200 ppm F and 0.2% TMP (200F-TMP); 200 ppm F, 16% Xylitol, 4% Erythritol, and 0.2% TMP (200F-X-E-TMP); and 7) 1,100 ppm F (1100F). Blocks were individually treated 2×/day with slurries of toothpastes and subjected to a pH cycling regimen for five days (DES: 6 hours and RE: 18 hours). Then, the percentage of surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), fluoride (F), calcium (Ca), and phosphorus (P) in enamel were determined. The data were analyzed by ANOVA (1-criterion) and the Student-Newman-Keuls test (p<0.001). Results: We found that the 200F-X-E-TMP treatment reduced %SH by 43% compared to the 1100F treatments (p<0.001). The ΔKHN was ~ 65% higher with 200F-X-E-TMP compared to 1100F (p<0.001). The highest concentration of F in enamel was observed on the 1100F treatment (p<0.001). The 200F-X-E-TMP treatment promote higher increase of Ca and P concentration in the enamel (p<0.001). Conclusion: The association of 200F-X-E-TMP led to a significant increase of the protective effect on enamel demineralization compared to the 1100F toothpaste.

Restoration of molars affected by molar-incisor hypomineralization using the occlusal replica technique / Restauração de molares afetados pela Hipomineralização Molar-Incisivo utilizando a técnica da réplica oclusal

ABSTRACT The aim of this study was to report the clinical case of an 8-year-old male patient seen at the Pediatric Dentistry outpatient clinic at the Universidade Federal do Paraná, Brazil, diagnosed with molar-incisor hypomineralization (MIH) after presenting with pain in teeth 16, 36, and 46, which had extensive atypical cavities and opacities on the adjacent enamel. A diagnostic wax-up of affected teeth was performed for manufacture of silicone occlusal matrix. Encapsulated high-viscosity glass ionomer cement was handled and inserted into the occlusal matrix which was fitted onto the teeth by slight finger pressure. After setting time, excess of material was removed, and occlusion was checked. A flowable resin coating material was applied, and the restorations were finished. Six months later, the restorations performed for treatment of the severe MIH lesions proved to be efficient, lowering the sensitivity reported by the patient, reshaping the teeth, improving their function, and refining dental esthetics.

RESUMO O objetivo deste estudo foi relatar um caso clínico de um paciente com diagnóstico de Hipomineralização de Molares e Incisivos (HMI). Paciente do sexo masculino, de 8 anos de idade, compareceu à clínica de Odontopediatria da Universidade Federal do Paraná com queixa de dor nos dentes 16, 36 e 46 - os quais apresentavam extensas cavitações atípicas com opacidades no esmalte adjacente. O enceramento diagnóstico dos dentes afetados foi realizado para a confecção das matrizes oclusais de silicone. Cimento ionômero de vidro de alta viscosidade encapsulado foi manipulado e inserido na matriz oclusal, a qual foi encaixada sobre os dentes, exercendo-se leve pressão digital. Após a presa do material os excessos foram removidos e a oclusão foi checada. Aplicou-se uma camada de resina fluída de cobertura e as restaurações foram finalizadas. Após seis meses, as restaurações realizadas para tratar as lesões severas de HMI mostraram-se eficazes, reduzindo a sensibilidade relatada pelo paciente, além de reestabelecerem a anatomia, função e estética dentária.

Influência do tipo de agente espessante e da suplementação de cálcio e fósforo no efeito desmineralizante de géis clareadores a base de peróxido de hidrogênio / Influence of the type of thickening agent and supplementation of calcium and phosphate on the demineralizing effect of bleaching gels based on hydrogen peroxide

O estudo avaliou o efeito da adição de cálcio (Ca) e fósforo (P), em quantidade correspondente ao ponto de saturação (PS) e ao coeficiente de solubilidade (CS), a géis clareadores contendo diferentes agentes espessantes na desmineralização do esmalte dentário. Foram manipulados géis clareadores contendo peróxido de hidrogênio (PH) a 35% e utilizados os espessantes carbopol 980 (CB); aerosil 200 (SP); poloxamer 407 (PX); goma guar (GG) e hidroxietilcelulose (HEC). Foram realizadas leituras iniciais da microdureza Knoop do esmalte empregando um microdurômetro, da rugosidade superficial em um perfilômetro de contato e da cor utilizando espectrofotômetro colorimétrico de reflectância. Os espécimes foram divididos em 5 grupos experimentais de acordo com o tipo de espessante. Cada grupo foi dividido em três subgrupos (n=20), de acordo com a suplementação mineral (0- nenhuma suplementação; PS ­ adição de Ca e P de acordo com o PS calculado para aquele espessante; CS ­ adição da quantidade máxima de Ca e P de acordo com o CS). Além disso, três grupos controles (n=20) foram preparados, sendo eles: CN (controle negativo ­água ultrapura); CP (controle positivo ­ PH a 35% sem a adição de qualquer mineral); CC (controle positivo comercial - gel comercial Whiteness HP). Sobre cada espécime foram aplicados 0,050 g dos respectivos géis clareadores, durante 45 min. Os dados dos grupos experimentais foram analisados estatisticamente com ANOVA a 2 fatores (TIPO DE ESPESSANTE x ADIÇÃO DE SAIS DE CA E P) e teste de Tukey. A comparação com os grupos controle foi realizada com o teste de Dunnett ( = 5%). Para todas as mensurações realizadas, a ANOVA mostrou diferenças significativas para os dois fatores (p<0,05). Para a alteração da microdureza, os resultados do teste de Tukey foram: TIPO DE ESPESSANTE (p=0,0001): HEC ­ 15,40(6,97)a, GG - 10,31(5,78)b, CB - 7,49(2,87)c, PX - 4,60(4,96)d, SP - 0,57(2,43)e; ADIÇÃO (p=0,0001): 0 - 12,34(7,22)a, S -10,31(5,76)b, CS -7,49(6,09)c. Para a alteração da rugosidade (p=0,0001), os resultados foram: TIPO DE ESPESSANTE (p=0,0001): SP - 5,19(23,36), GG - 9,70(17,75)ab, PX - 15,95(20,79)b, HEC - 53,58(71,82)c, CB - 55,49(63,69)c; ADIÇÃO (p=0,0001): 0 - 79,62(58,70)a, S - 3,23(12,08)a, CS - 1,09(9,44)b. Para a mudança de cor (ΔE), os resultados foram: TIPO DE ESPESSANTE (p=0,0001): SP - 5,40(2,92)a, GG - 3,13(1,83)a, PX - 3,18(2,57)ab, HEC - 3,82(2,05)bc, CB - 4,79(3,26)c. ADIÇÃO (p=0,2853): 0 - 4,37(2,60)a, S - 4,04(3,07)a, CS - 3,79(2,42)a. Os resultados para o teste de Dunnett para a microdureza: os grupos SP, SP-S e SP-CS não demonstraram diferenças com o grupo CN, e apenas os grupos GG e HEC-S não demostraram diferenças com o grupo CP e o grupo HEC-S para o CPC. Para a rugosidade, os grupos CB-CS, SP, PX-S, PX-CS, GG-S e GG-CS não demonstraram diferenças em relação ao grupo CN e todos os grupos apresentaram diferenças significativas para os grupos CP e CPC. Mediante os resultados desse estudo, podemos concluir que: A adição de cálcio e/ou fósforo em quantidades correspondente ao PS ou ao CS apenas do grupo SP impediu a queda da dureza e o aumento da rugosidade. Os demais grupos apresentaram alterações, porém sem afetar o tratamento clareador. (AU)

The aim of the study was to evaluate the effect of adding calcium (Ca) and phosphorus (P), in amounts corresponding to the saturation concentration (SC) and the solubility limit (SL), to bleaching gels containing different thickening agents on the demineralization of tooth enamel. Bleaching gels containing 35% hydrogen peroxide (PH) were manipulated and the thickeners were used: carbopol 980 (CB); aerosil 200 (SP); poloxamer 407 (PX); guar gum (GG) and hydroxyethylcellulose (HEC). The baseline readings of Knoop microhardness of the enamel using a microhardness, surface roughness using a contact profilometer and color using a colorimetric reflectance spectrophotometer were taken. The specimens were divided into 5 experimental groups according to the type of thickener. Each group was divided into three subgroups (n=20), according to mineral supplementation (0 - no supplementation; SC - addition of Ca and P according to the SC calculated for that thickener; SL - addition of the maximum amount of Ca and P according to SL). In addition, three control groups (n=20) were prepared, namely: NC (negative control ­ ultra pure water); PC (positive control ­ 35% pH without the addition of any mineral); CC (commercial positive control - commercial Whiteness HP gel). Were applied 0.050 g of the respective bleaching gels to each specimen for 45 min. The microhardness and surface roughness of the samples were measured immediately after bleaching. All samples were then immersed in artificial saliva for 7 days and the final color evaluated. Data from the experimental groups were statistically analyzed with 2-way ANOVA (THICKENER TYPE x MINERAL SUPPLEMENTATION) and Tukey test. Comparison with control groups was performed using Dunnett's test ( = 5%). For all measurements performed, ANOVA showed significant differences for the two factors (p<0.05). For microhardness change, the Tukey test results were: THICKENER TYPE (p=0.0001): HEC - 15.40(6.97)a, GG - 10.31(5.78)b, CB - 7.49(2.87)c, PX - 4 .60(4.96)d, SP - 0.57(2.43)e; ADDITION (p=0.0001): 0 - 12.34(7.22)a, SC -10.31(5.76)b, SL -7.49(6.09)c. For roughness change (p=0.0001), the results were: TYPE OF THICKENER (p=0.0001): SP - 5.19(23.36), GG - 9.70(17.75)ab, PX - 15.95(20.79)b, HEC - 53.58(71.82)c, CB - 55.49(63.69)c; ADDITION (p=0.0001): 0 - 79.62(58.70)a, SC - 3.23(12.08)a, SL - 1.09(9.44)b. For the color change (ΔE), the results were: TYPE OF THICKENER (p=0.0001): SP - 5.40(2.92)a, GG - 3.13(1.83)a, PX - 3.18(2.57)ab, HEC - 3.82(2.05)bc, CB - 4.79(3.26)c. ADDITION (p=0.2853): 0 - 4.37(2.60)a, SC - 4.04(3.07)a, SL - 3.79(2.42)a. The results for the Dunnett test for microhardness were: the SP, SP-S and SP-CS groups did not show differences with the CN group, and only the GG and HEC-S groups did not show differences with the CP group and the HEC-S for the CPC. For roughness, the CB-CS, SP, PX-S, PX-CS, GG-S and GG-CS groups did not show differences in relation to the CN group and all groups showed significant differences for the CP and CPC groups. By the results of this study, we can conclude that: The addition of calcium and/or phosphorus in amounts corresponding to the SC or to the SL of the aerosil group only prevented the drop in hardness and the increase in roughness. (AU)

Longitudinal assessment of dental erosion-abrasion by cross-polarization optical coherence tomography in vitro

Abstract: This study tested a novel in vitro dental erosion-abrasion model and the performance of cross-polarization optical coherence tomography (CP-OCT) in longitudinally monitoring the simulated lesions. Thirty human enamel specimens were prepared and randomized to receive three dental erosion-abrasion (EA) protocols: severe (s-EA, lemon juice/pH:2.5/4.25%w/v citric acid), moderate (m-EA, grapefruit juice/pH:3.5/1.03%w/v citric acid) and no-EA (water, control). EA challenge was performed by exposing the specimens to acidic solutions 4x/day and to brushing 2x/day with 1:3 fluoridated toothpaste slurry, for 14 days. Enamel thickness measurements were obtained using CP-OCT at baseline (D0), 7 (D7) and 14 days (D14) and micro-computed tomography (micro-CT) at D14. Enamel surface loss was measured with both CP-OCT and optical profilometry at D0, D7 and D14. Data was analyzed with repeated-measures ANOVA and Pearson's correlation (r) (α = 0.05). CP-OCT enamel thickness decreased over time in the s-EA group (D0 >D7 > D14, p < 0.001) and m-EA group (D0 > D14, p = 0.019) but did not change in the no-EA group (p = 0.30). Overall, CP-OCT and micro-CT results at D14 correlated moderately (r = 0.73). CP-OCT surface loss was highest for s-EA (p <0.001) but did not differ between moderate and no-EA (p = 0.25). Enamel surface loss with profilometry increased with severity (no-EA>m-EA>s-EA, p < 0.001). D14 surface loss was higher than D7 for both methods except for the no-EA group with profilometry. CP-OCT and profilometry had moderate overall correlation (r = 0.70). Our results revealed that the currently proposed in vitro dental erosion-abrasion model is valid and could simulate lesions of different severities over time. CP-OCT was a suitable method for monitoring the EA lesions.

YouTubeTM as a Tool to Teach Dentists about Molar Incisor Hypomineralization (MIH): Analysis of Quality Content

ABSTRACT Objective: To evaluate the quality of information about Molar incisor Hypomineralization (MIH) on YouTubeTM. Material and Methods: Only videos in Portuguese aimed at dentists were included. The selected videos were analyzed by two calibrated evaluators, who extracted the information (classification, etiology, diagnosis, and treatment of MIH) and the quality was evaluated through a 20-point-checklist, according to the International Association of Pediatric Dentistry and European Academy of Pediatric Dentistry. Descriptive analysis and statistical tests were applied to assess the association (ANOVA and Kruskal-Wallis) or correlation (Spearman) between the final scores of the videos and their demographics. Results: Nineteen videos with 13.8±4.76 mean points were considered eligible. Most of the videos did not report the possible involvement of other groups of teeth (n=12), presence of atypical restorations (n=8) and hypersensitivity (n=7); and the different treatments for MIH were very variable. Twelve videos discussed differential diagnosis and 78.95% possible etiological factors; however, all of them presented clinical images. Data related to the video source and viewer interaction were not related to its quality (p>0.05). The number of likes (r=0.26), views (r=0.34) and video time (=0.58) show a weak and moderate correlation, respectively, with video score. Conclusion: Videos on YouTubeTM about MIH presented moderate or high quality, with heterogeneous information, and can act as a complementary aid source of information.

Fluorotic Enamel Susceptibility to Dental Erosion and Fluoride Treatment

Abstract The purpose of this in vitro study was to test the hypothesis that fluoride treatment can prevent dental erosion on fluorotic enamel of different severities. It followed a 3×2 factorial design, considering a) fluorosis severity: sound (TF0, Thylstrup-Fejerskov Index), mild (TF1-2), moderate (TF3-4); and b) fluoride treatment: 0 (negative control) and 1150ppmF. Human molars with the three fluorosis severities (n=16, each) were selected and randomly assigned to the two fluoride treatments (n=8). Enamel blocks (4×4mm) were prepared from each tooth and subjected to a dental erosion cycling model, for 10 days. The daily cycling protocol consisted of erosive challenges (1% citric acid, pH 2.4), interspersed by periods of immersion in artificial saliva, and three 2-minute treatments with either 0 or 1150ppm F. The enamel volume loss (mm3) was calculated by subtracting values obtained by microtomography before and after cycling. Two-Way ANOVA showed no significant interaction between fluorosis severity and fluoride treatment (p=0.691), and no significant effect for either fluorosis severity (TF0 mean±standard-deviation: 13.5(10-2±0.42(10-2, TF1-2: 1.50(10-2±0.52(10-2, TF3-4: 1.24(10-2±0.52(10-2, p=0.416) or treatment (0ppmF: 1.49(10-2±0.53(10-2; 1150ppmF: 1.21(10-2±0.42(10-2; p=0.093), when evaluated independently. Considering the limitations of this in vitro study, the presence and severity of fluorosis in enamel do not appear to affect its susceptibility to dental erosion. Fluoride treatment was not effective in preventing the development of dental erosion in both sound and fluorotic enamel substrates under our experimental conditions.

Resumo Este estudo in vitro foi testou a hipótese de que o tratamento com flúor pode prevenir a erosão dentária no esmalte fluorótico de diferentes severidades. O objetivo deste estudo foi: investigar o efeito protetor dos fluoretos contra a erosão e abrasão simuladas no esmalte fluorótico. Seguiu um desenho fatorial 3×2, considerando a) severidade da fluorose em 3 níveis: hígido (TF0, Índice Thylstrup-Fejerskov), suave (TF1-2), moderada (TF3-4); b) tratamento com flúor: 0 (controle negativo) e 1150ppmF. Molares humanos com as três severidades de fluorose (n=16, cada) foram selecionados e distribuídos aleatoriamente para os dois tratamentos com flúor (n=8). Blocos de esmalte (4×4mm) foram preparados a partir de cada dente e submetidos a um modelo de ciclo de erosão dentária, por 10 dias. O protocolo de ciclagem diária consistiu em seis desafios erosivos de 5 minutos (1% de ácido cítrico, pH 2,4), intercalados por seis períodos de imersão em saliva artificial e três tratamentos de 2 minutos com 0 ou 1150ppmF. O volume do esmalte perdido foi calculado subtraindo o perfil superficial 3D obtido por microtomografia antes e depois da ciclagem. A ANOVA de dois fatores não mostrou interação significativa entre a severidade da fluorose e o tratamento com flúor (p = 0,691) e nenhum efeito significativo para a severidade da fluorose (TF0 média+/desvio padrão: 13,5(10-2±0,42(10-2, TF1-2: 1,50(10-2±0,52(10-2, TF3-4: 1,24(10-2±0,52(10-2, p=0,416) ou tratamento (0: 1,49(10-2±0,53(10-2; 1150ppmF: 1,21(10-2±0,42(10-2, p=0,093), quando avaliados independentemente. Considerando as limitações deste estudo in vitro, a presença e severidade da fluorose no esmalte não parece afetar sua suscetibilidade à erosão dentária. O tratamento com flúor não foi eficaz na prevenção do desenvolvimento da erosão dentária em esmalte hígido e fluorótico, sob as condições experimentais utilizadas.