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OBJECTIVE: This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models. METHODOLOGY: In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (α=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (ΔF) and integrated fluorescence (ΔQ) in comparison to the other two protocols (p<0.001). RESULTS: In addition, Ss+Lc resulted in significantly deeper WSL (137.5 µm), followed by Ss (84.1 µm) and Sm (54.9 µm) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols. CONCLUSION: The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.
Asunto(s)
Biopelículas , Caries Dental , Esmalte Dental , Lacticaseibacillus casei , Streptococcus mutans , Humanos , Streptococcus mutans/fisiología , Caries Dental/microbiología , Caries Dental/terapia , Esmalte Dental/microbiología , Esmalte Dental/química , Lacticaseibacillus casei/fisiología , Factores de Tiempo , Reproducibilidad de los Resultados , Streptococcus sobrinus/fisiología , Espectrometría Raman , Análisis de Varianza , Microscopía de Polarización , Estadísticas no Paramétricas , Remineralización Dental/métodos , Valores de Referencia , Saliva/microbiología , Saliva/química , Desmineralización Dental/microbiología , FluorescenciaRESUMEN
O objetivo deste estudo foi caracterizar e comparar o esmalte sadio humano e lesões de mancha branca (ICDAS 2) em diferentes aspectos. Dezessete espécimes foram caracterizados por meio fluorescência com o Diagnodent®, Fluorescência quantitativa induzida pela luz (QLF®), quanto aspectos ópticos pela Tomografia de Coerência Óptica (OCT), propriedades mecânicas com a Microdureza seccional e avaliação do conteúdo inorgânico e orgânico com a Espectroscopia Raman. A ANOVA e teste de Tukey, foram utilizados com 5% como nível de significância. O Diagnodent® identificou 75% das superfícies como hígidas, 7% cárie em esmalte, 10% lesão até junção esmalte-dentina e 7% cárie em dentina. Para o QLF®, a perda de conteúdo mineral Q (%mm2) foi de 15,37%mm2 e a diferença de fluorescência (F) foi de 11,68%. O aparelho OCT captou uma média de profundidade de lesões de 174,43 m, e um coeficiente de atenuação sem diferença significante (p>0,005). A microdureza demonstrou uma diferença significante (p<0,005) quando comparados os fatores: camada superficial e corpo do esmalte (hígido e lesão), porém não existe diferença significante (p>0,005), quando comparados esses dois sítios dentro do mesmo substrato. O espectro Raman demonstrou as 4 bandas vibracionais do fosfato (v1, v2, v3, v4) com maior intensidade no esmalte hígido, sendo o maior pico em 960,3 cm-1(v1). Em 1071 cm-1, a intensidade foi maior para o esmalte hígido, correspondendo a banda do fosfato (v3) e não o carbonato tipo B. O conteúdo orgânico foi visto em 1295 cm-1 e em 1450 cm-1, com maior intensidade nas lesões. A variabilidade de características dos substratos estudados interferiu diretamente na caracterização destes pelos métodos propostos.
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Esmalte DentalRESUMEN
Abstract Creating artificial caries-like lesions that mimic the complex changes observed in natural caries is essential for properly evaluating new strategies, dental materials, and devices designed to arrest their progression and avoid more costly and invasive treatments. Objective This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models. Methodology In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (α=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (ΔF) and integrated fluorescence (ΔQ) in comparison to the other two protocols (p<0.001). Results In addition, Ss+Lc resulted in significantly deeper WSL (137.5 µm), followed by Ss (84.1 µm) and Sm (54.9 µm) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols. Conclusion The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.
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Objective: To compare optical, morphological, chemical, and physical aspects of the sound enamel and white spot lesions (WSL) classified as ICDAS 2. Material and Methods: Seventeen human molars with one surface presenting WSL and a sound surface (2 x 2 mm window) were characterized by Quantitative light-induced fluorescence (QLF ®), Optical coherence tomography (OCT), microhardness, and Raman spectroscopy. The ANOVA and Tukey's test were used at 5% significance level. Results: The QLF comparison between distinct substrates yielded decreased ∆Q (integrated fluorescence loss) of -15,37%mm2 and -11,68% ∆F (fluorescence loss) for WSL. The OCT detected mean lesion depth of 174,43 µm. ANOVA could not detect differences in the optical attenuation coefficient between the substrates (p>0.05). Lower microhardness measures were observed in WSL than on sound enamel (p<0.05). The Raman spectra showed four vibrational phosphate bands (v1, v2, v3, v4), where the highest peak was at 960.3 cm-1(v1) for both substrates. However, a 40% decrease in phosphate (v1) was detected in WSL. The peak at 1071 cm-1 was higher for sound enamel, indicating the presence of a phosphate band instead of the B-type carbonate. The spectra showed higher intensity of the organic composition at 1295 cm-1 and 1450 cm -1 for WSL. Conclusion: Non-invasive QLF, OCT and Raman spectroscopy were able to distinguish differences in fluorescence, optical properties, and organic/inorganic components, respectively, between sound enamel and WSL, validated by the destructive microhardness analysis. (AU)
Objetivo: Comparar os aspectos ópticos, morfológicos, químicos e físicos do esmalte sadio e das lesões de mancha branca naturais, classificada como ICDAS 2. Material e métodos: Dezessete molares humanos com uma face apresentando uma lesão de mancha branca natural e outra face o esmalte hígido (2 x 2 mm) foram caracterizados utilizando a Fluorescência quantitativa induzida pela luz (QLF ®), Tomografia de coerência óptica (OCT), Microdureza e Espectroscopia Raman. A ANOVA e o teste de Tukey foram utilizados ao nível de significância de 5%. Resultados: A comparação entre os substratos distintos, utilizando o QLF ® demonstrou uma diminuição no ∆Q (perda de fluorescência integrada) de -15,37%mm2 e -11,68% de ∆F (Perda de fluorescência) para a lesão de mancha branca. O OCT detectou uma profundidade média de lesão de 174,43µm. A ANOVA não detectou diferenças no coeficiente de atenuação óptica entre os substratos (>0,05). Microdureza significantemente menor foi detectada nas lesões de mancha branca do que no esmalte sadio (p<0,05). Os espectros Raman mostraram quatro bandas vibracionais do fosfato (v1,v2,v3,v4), onde o maior pico foi em 960,3cm-1para ambos os substratos. No entanto, uma diminuição de 40% no fosfato (v1) foi detectada na lesão. O pico em 1071cm-1foi maior para o esmalte hígido, demonstrando tratar-se da banda do fosfato, ao invés do carbonato tipo B. Os espectros apresentaram maior intensidade da composição orgânica em 1295cm-1e 1450 cm-1para a lesão de mancha branca. Conclusão:Os métodos não invasivos QLF, OCT e espectroscopia Raman foram capazes dediferenciar a fluorescência, propriedades ópticas e conteúdo orgânico/inorgânico do esmalte sadio comparado com esmalte com lesões de mancha branca, sendo validado pela análise de microdureza. (AU)
Asunto(s)
Espectrometría Raman , Caries Dental , Esmalte Dental , DiagnósticoRESUMEN
O objetivo deste estudo foi caracterizar e comparar o esmalte sadio humano e lesões de mancha branca (ICDAS 2) em diferentes aspectos. Dezessete espécimes foram caracterizados por meio fluorescência com o Diagnodent®, Fluorescência quantitativa induzida pela luz (QLF®), quanto aspectos ópticos pela Tomografia de Coerência Óptica (OCT), propriedades mecânicas com a Microdureza seccional e avaliação do conteúdo inorgânico e orgânico com a Espectroscopia Raman. A ANOVA e teste de Tukey, foram utilizados com 5% como nível de significância. O Diagnodent® identificou 75% das superfícies como hígidas, 7% cárie em esmalte, 10% lesão até junção esmalte-dentina e 7% cárie em dentina. Para o QLF®, a perda de conteúdo mineral Q (%mm2) foi de 15,37%mm2 e a diferença de fluorescência (F) foi de 11,68%. O aparelho OCT captou uma média de profundidade de lesões de 174,43 m, e um coeficiente de atenuação sem diferença significante (p>0,005). A microdureza demonstrou uma diferença significante (p<0,005) quando comparados os fatores: camada superficial e corpo do esmalte (hígido e lesão), porém não existe diferença significante (p>0,005), quando comparados esses dois sítios dentro do mesmo substrato. O espectro Raman demonstrou as 4 bandas vibracionais do fosfato (v1, v2, v3, v4) com maior intensidade no esmalte hígido, sendo o maior pico em 960,3 cm-1(v1). Em 1071 cm-1, a intensidade foi maior para o esmalte hígido, correspondendo a banda do fosfato (v3) e não o carbonato tipo B. O conteúdo orgânico foi visto em 1295 cm-1 e em 1450 cm-1, com maior intensidade nas lesões. A variabilidade de características dos substratos estudados interferiu diretamente na caracterização destes pelos métodos propostos.
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Desmineralización , Caries Dental , Esmalte DentalRESUMEN
Introduction: The labial frenum is a fold of mucous membrane that attaches the lip and the cheek to the alveolar mucosa, the gingiva, and the underlying periosteum. In some cases, its presence can cause a midline diastema, periodontal diseases related to food impaction, or retention of biofilm, among others. In such cases, lip frenectomy is indicated as treatment, which can be performed with a scalpel (conventional method), an electric scalpel, or a surgical laser. Objective: To show a clinical case performed at Laser Extension Project in Dentistry, Federal University of Maranhão grounded in a literature review. Case Presentation: A laser frenectomy was performed on a female patient, aged 20, who had a diastema between the upper central incisors and an indication for frenum removal. The high-power diode laser is excellent for procedures in soft tissue because its wavelength is well absorbed by hemoglobin and other pigments; its use also allows a reduction in the amount of anesthetic and medicines used. The parameters used were 2 W, in a continuous mode, 808 nm infrared emission; with delivery of the beam through optical fiber 300 µM; energy of 120 J; 20 pps. Conclusion: the high power diode laser allowed a satisfactory result, the procedure was safe, the technique was a simple one and of reduced clinical time, as mentioned in the literature. It is worth noting that the technique is dependent on the skill of the professional performing it.
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The aim of this in vitro study was to assess the influence of distinct surface treatments on the microhardness and color of enamel that will be bleached. Surface treatments are tested, accordingly: G1, no treatment; G2, 2% sodium fluoride; G3, casein phosphopeptide paste; G4, 2% fluoride+Nd:YAG laser. Forty blocks from bovine teeth composed the sample that were tested in Knoop microhardness (n = 10) and in color change (n = 10). After 24 h, bleaching with 35% hydrogen peroxide was performed for 45 min. Microhardness and color changes (using parameters ΔE, ΔL, Δa, and Δb) were assessed before and after bleaching. The data were analyzed by two-way ANOVA and Tukey's test (p < 0.05). Despite all surface treatments, a reduction of enamel microhardness occurred immediately after bleaching in all groups, being greater in G1. Enamel color changed in all groups. Immediately after bleaching, there was a decrease on enamel microhardness. However, after 7 days, some of those specimens previously treated before bleaching significantly recovered their initial microhardness without influencing the esthetic results of bleaching.