Influência da técnica de utilização das pastas de prova (try-in) na cor de um cimento resinoso fotopolimerizável / Influence of the try-in technique on the color of a light-curing resin cement

Objetivo: Avaliar a influência da técnica de aplicação e remoção da pasta de prova (Try-in) na cor de um cimento resinoso fopolimerizável. Material e Métodos: Preparo de 40 dentes bovinos e 40 laminados cerâmicos (IPS e-max Ceram, Ivoclar/Vivadent AG Schaan, Liechtenstein) com espessura de 0,5 mm. Estes foram alocados aleatoriamente em 4 grupos (n=10) segundo a técnica para aplicação e remoção da pasta de prova: G1 – Aplicação de ácido fluorídrico, silano, adesivo, Try-in (AcFSAT)+ banho em cuba ultrassônica com água destilada por 5 minutos (CU) + nova aplicação de ácido fluorídrico, silano, adesivo (AcFSA) + cimentação definitiva (CD); G2 – Aplicação de AcFSAT + Pulverização de água/ar por 1 minuto + nova aplicação de AcFSA + CD; G3 Try-in + CU + aplicação de AcFSA + CD; G4 –Try-in + Pulverização de água/ar por 1 minuto + aplicação de AcFSA + CD. As leituras de cor foram realizadas após a aplicação do Try-in e após a cimentação definitiva utilizando o sensor digital VITA Easyshade modelo Advance 4.0. Os dados obtidos foram submetidos a análise estatística por meio de aplicação dos testes de ANOVA (p=0,003) e complementar de Bonferroni. Resultados: O fator Aplicação teve efeito significante sobre a alteração de cor (?E*), em que o grupo submetido a aplicação do Try-in de forma direta apresentou menor ?E* (3,65± 0,25) entre a prova e cimentação definitiva da cerâmica em comparação ao grupo que aplicou ácido+silano+adesivo+Try-in (4,80±0,25). O fator Remoção não apresentou diferença estatisticamente significante entre os grupos. E a interação Aplicação x Remoção foi significante, onde G1 (3,94±0,35) e G3 (4,23±0,35) são estatisticamente semelhantes, G2 apresentou valores maiores (5,68±0,35) e G4 (3,08 (±0,35)) apresentou menor ?E*. Conclusão: Conclui-se que o melhor método para prova de laminados cerâmicos é a utilização da técnica direta da pasta de prova (Try-in) com posterior remoção através do processo de jato de ar/água durante um minuto; não houve alteração significante de cor quando visto de forma isolada os métodos de remoção da pasta de prova; a técnica de aplicação direta do Try-in apresentou menor alteração de cor; todas as técnicas de aplicação e remoção analisadas apresentaram alterações de cor perceptíveis ao olho humano

Effect of strontium carbonate and calcium carbonate nanoparticles partially substituted by strontium on remineralization and tubular obliteration of dentin

O objetivo deste estudo foi avaliar a capacidade de remineralização e obliteração tubular da dentina submetida a tratamento com agentes dessensibilizantes de carbonato de estrôncio e carbonato de cálcio parcialmente substituído por estrôncio, por meio da análise das propriedades químicas e morfológicas da dentina. Foram utilizados os seguintes agentes dessensibilizantes: D1 - SrCO3 (Carbonato de Estrôncio); D2 - SrxCa1-xCO3 (Carbonato de Cálcio parcialmente substituído por Estrôncio); D3 - CaCO3 (Carbonato de Cálcio), D4 - Acetato de Estrôncio (Sensodyne® Rápido Alívio) (controle positivo) e D5 - Colgate® My First (controle negativo). Inicialmente, foram feitas as sínteses de partículas de SrCO3, SrxCa1-xCO3 e CaCO3 que fazem parte das formulações que foram testadas. A fim de caracterizar as nanopartículas produzidas, realizou-se análises de Difração de Raio X, Diâmetro hidrodinâmico, Carga superficial e Microscopia Eletrônica de Varredura. Na sequência, preparou-se o gel de nanopartículas, partindo-se da mistura de cada nanopartícula com gel de Poli (Álcool Vinílico) (PVA), e a fim de caracterizar o gel conforme sua viscosidade, realizou-se tal análise utilizando um Reômetro. Para análises química e morfológica da dentina, foram utilizados 30 terceiros molares humanos hígidos extraídos, seccionados acima da junção amelocementária, obtendo-se 30 discos de dentina de 1mm de espessura. Dentre os 30 discos, 25 foram selecionados para serem escovados de acordo com os grupos experimentais propostos, e 5 para verificação complementar da escovação associada com o efeito do desafio ácido. O tratamento dessensibilizante consistiu de dois ciclos de escovação por dia, onde os espécimes foram levados à máquina de simulação de escovação mecânica, fixados e escovados por 10 segundos. Uma hora após, os espécimes selecionados para o desafio ácido foram condicionados em refrigerante de cola (Coca® Cola) sob agitação por 2 minutos, com auxílio de mesa agitadora. Os espécimes foram submetidos à análise de Composição Química da dentina por meio de Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) nos tempos experimentais de T0 (inicial), T1 (01 dia), T2 (07 dias) e T3 (14 dias), e Espectroscopia por Dispersão de Raios X (EDS) nos tempos de Inicial e 14 dias, e à análise de Percentual e Profundidade de obliteração dos túbulos dentinários por meio de um Microscópio Eletrônico de Varredura (MEV) nos tempos Inicial e 14 dias. Resultados: As análises de FTIR mostraram variações de composição relacionadas ao aumento da quantidade de grupos carbonatos sobre a superfície dentinária. Os espectros de EDS indicaram a presença de estrôncio nas amostras escovadas com D1 e D2, e considerável aumento após desafio ácido, em comparação aos demais grupos. E as imagens de MEV mostraram que a presença dos grupos carbonatos estavam relacionados com a deposição das nanopartículas que não foram removidas após o desafio ácido. Conclui-se que as nanopartículas experimentais de SrCO3 (D1) e SrxCa1-xCO3 (D2) foram eficazes na obliteração e remineralização parcial da dentina, com recobrimento estável após desafio ácido.The aim of this study was to evaluate the remineralization and tubular obliteration capacity of dentin submitted to treatment with desensitizing agents of strontium carbonate and calcium carbonate partially substituted by strontium by analyzing the chemical and morphological properties of dentin. Were used the following desensitizing agents: D1 - SrCO3 (Strontium Carbonate); D2 - SrxCa1-xCO3 (Calcium Carbonate partially substituted by Strontium); D3 - CaCO3 (Calcium Carbonate), D4 - Strontium Acetate (Sensodyne® Rapid Relief) (positive control) and D5 - Colgate® My First (negative control). Initially, were made the syntheses of SrCO3, SrxCa1-xCO3 and CaCO3 particles that are part of the formulations that were tested. In order to characterize the nanoparticles produced, analyzes were performed of X-ray Diffraction, Hydrodynamic Diameter, Surface Load and Scanning Electron Microscopy. Subsequently, the nanoparticle gel was prepared, starting from the mixture of each nanoparticle with Polyvinyl Alcohol (PVA) gel, and in order to characterize the gel according to its viscosity, such analysis was performed using a Rheometer. For chemical and morphological analysis of dentin, 30 extracted healthy human third molars were sectioned above the cementoenamel junction, obtaining 30 dentin discs of 1mm thickness. Of the 30 discs, 25 were selected to be brushed according to the proposed experimental groups, and 5 to further check brushing associated with the effect of acid challenge. The desensitizing treatment consisted of two brushing cycles per day, where the specimens were taken to the mechanical brushing simulation machine, fixed and brushed for 10 seconds. One hour later, the specimens selected for the acid challenge were conditioned in cola soda (Coca® Cola) under agitation for 2 minutes, with the aid of a shaker table. The specimens were submitted to dentin chemical composition analysis by Fourier Transform Infrared Spectroscopy (FTIR) at the experimental times of T0 (initial), T1 (01 day), T2 (07 days) and T3 (14 days) and X-ray Dispersion Spectroscopy (EDS) at the Initial and 14 days times, and the Percentage and Depth of Obliteration analysis of the dentinal tubules by means of a Scanning Electron Microscope (SEM) at the Initial and 14 days. Results: FTIR analyzes showed composition variations related to the increase in the number of carbonate groups on the dentin surface. The EDS spectra indicated the presence of strontium in the brushed samples with D1 and D2, and considerable increase after acid challenge, compared to the other groups. And SEM images showed that the presence of carbonate groups was related to the deposition of nanoparticles that were not removed after the acid challenge. It was concluded that experimental SrCO3 (D1) and SrxCa1-xCO3 (D2) nanoparticles were effective in obliteration and partial remineralization of dentin, with stable coating after acid challenge

The Antibacterial and Antifungal Capacity of Eight Commercially Available Types of Mouthwash against Oral Microorganisms: An In Vitro Study

This work aimed to evaluate and compare the antimicrobial actions and effects over time of eight types of mouthwash, based on the impact of chlorhexidine on the main microorganisms that are responsible for oral diseases: Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans. The mouthwashes’ antimicrobial action was determined in terms of their minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC), and time-kill curves at different contact times (10 s, 30 s, 60 s, 5 min, 15 min, 30 min, and 60 min), against selected oral microorganisms. All the mouthwashes showed a notable effect against C. albicans (MICs ranging from 0.02% to 0.09%), and higher MIC values were recorded with P. aeruginosa (1.56% to >50%). In general, the mouthwashes showed similar antimicrobial effects at reduced contact times (10, 30, and 60 s) against all the tested microorganisms, except with P. aeruginosa, for which the most significant effect was observed with a long time (15, 30, and 60 min). The results demonstrate significant differences in the antimicrobial actions of the tested mouthwashes, although all contained chlorhexidine and most of them also contained cetylpyridinium chloride. The relevant antimicrobial effects of all the tested mouthwashes, and those with the best higher antimicrobial action, were recorded by A—GUM® PAROEX®A and B—GUM® PAROEX®, considering their effects against the resistant microorganisms and their MIC values

Static Bacterial Leakage in Different Conometric Connections: An In Vitro Study

This in vitro study aims to evaluate the bacterial microleakage of three conometric connections. Sixty dental implants (3P implafavourite Scalenghe) were divided in groups (n = 20): Cone–Morse with passing screw (Group 1); Cone–Morse with solid abutment (Group 2); and Conometric connection with esthetic abutment (Group 3). The implants were fixed in resin bases. Then, 1.0 µL of Streptococcus oralis (SO) was inoculated in the internal platform in 10 fixtures for each group, and another 10 were inoculated with Pseudomonas aeruginosa (PA). The abutments were then screwed, and five implants from each subgroup were randomly selected for SEM inspection to ensure that the abutments were installed correctly. Data were submitted to statistical analysis, ANOVA and Fisher’s Least Significant Difference (p ≤ 0.05). The turbidity of the broth was monitored for 14 days of follow-up in order to determine the penetration of the bacterial suspension into the surrounding solution, but the observation of the samples lasted until the 90th day, in which there was no difference between the two. Microbial contamination was found in 30%, 20%, and 50% of Group 1, Group 2, and Group 3, respectively, but there were no statistically significant differences between the groups, and PA showed greater infiltration than SO. Although no statistically significant differences were found, cone morse connections showed lower infiltration percentages, respective to the conometric connection with 18° angle

Effect of light curing unit and antiseptic mouthwashes on the physical properties of gingiva-colored composite resin

Objective: This study evaluated surface roughness (Ra) and color difference (ΔE00) of a gingiva-colored composite resin (NT Premium Gengiva, Coltene), light-activated with three light curing units (LCU) and immersed in different mouthwash solutions. Methods: 90 composite specimens (n=10) were divided according to the LCU: L1-Valo, L2-Bluephase and L3-Optilight Max; and solution: S1-alcohol-based antiseptic mouthwash (Listerine Cool Mint), S2-alcohol-free antiseptic mouthwash (Listerine Cool Mint Zero Alcohol) and S3-water (control). Immersions were performed for 30 s, 2x/day, for 21 days. Ra and coordinates of luminosity (L*) and color (a* and b*) were measured using a rugosimeter (SJ-201 P/M) and a spectrophotometer (SP62S), respectively, at: T0-start, T1-7 days, T2-14 days and T3-21 days. Results: L1 (1.3±0.9) presented higher Ra than L3 (0.7±0.6) and L2 (1.0±0.8); and Ra for S2 (0.9±0.1) was greater than S3 (-0.1±0.1), and S1 (0.1±0.1). Moreover, L1 (23.3±0.3) presented lower ΔE00 t han L 2 (24.7±0.3) a nd L 3 (25.1±0.3). Conclusion: Ra of the gingiva-colored composite resin tested increased when L1 and S2 were used, although L1-cured specimens also showed the lowest ΔE00.Objetivo: Este estudo avaliou a rugosidade superficial (Ra) e a diferença de cor (∆E00) de um compósito de resina composta cor de gengiva (NT Premium Gengiva, Coltene), fotopolimerizável com três unidades fotopolimerizáveis (UFP) e imersa em diferentes soluções de enxaguantes. Métodos: Ao todo, 90 espécimes de compósitos (n=10) foram divididos de acordo com o UFP: L1-Valo, L2-Bluephase e L3-Optilight Max; e solução: S1-enxaguante bucal antisséptico à base de álcool (Listerine Cool Mint), S2-enxaguante bucal antisséptico sem álcool (Listerine Cool Mint Zero Alcohol) e S3-água (controle). As imersões foram realizadas por 30 s, 2×/dia, por 21 dias. Ra e coordenadas de luminosidade (L*) e cor (a* e b*) foram medidas usando um rugosímetro (SJ-201 P/M) e um espectrofotômetro (SP62S), respectivamente, em: T0-início, T1-7 dias, T2-14 dias e T3-21 dias. Resultados: L1 (1,3±0,9) apresentou Ra maior que L3 (0,7±0,6) e L2 (1,0±0,8); e Ra para S2 (0,9±0,1) foi maior do que S3 (-0,1±0,1) e S1 (0,1±0,1). Além disso, L1 (23,3±0,3) apresentou ∆E00 menor que L2 (24,7±0,3) e L3 (25,1±0,3). Conclusão: O Ra do compósito de resina cor de gengiva testado aumentou quando L1 e S2 foram usados, embora os espécimes curados com L1 também tenham apresentado o menor ∆E00

5-Aminolevulinic Acid and Red Led in Endodontics: A Narrative Review and Case Report

The present study aims to discuss the main factors involving the use of 5-aminolevulinic acid together with red LED light and its application in endodontic treatment through a narrative review and a case report. Persistence of microorganisms remaining on chemical-mechanical preparation or intracanal dressing is reported as the leading cause of failure in endodontics. Photodynamic therapy has become a promising antimicrobial strategy as an aid to endodontic treatment. Being easy and quick to apply, it can be used both in a single session and in several sessions, as well as not allowing forms of microbial resistance. 5-aminolevulinic acid in combination with red LED light has recently been studied in many branches of medicine, with good results against numerous types of bacteria including Enterococuss faecalis. The case report showed how bacterial count of CFU decreased by half (210 CFU/mL), after 45 min of irrigation with a gel containing 5% of 5-aminolevulinic acid compared to the sample before irrigation (420 CFU/mL). The subsequent irradiation of red LED light for 7 min, the bacterial count was equal to 0. Thus, it is concluded that the use of 5-aminolevulinic acid together with red LED light is effective in endodontic treatment

Efficacy of 5% Aminolaevulinic Acid and Red Light on <i>Enterococcus faecalis</i> in Infected Root Canals

Background: In this ex vivo study, the aim was to evaluate the effects of ALAD and red light on Enterococcus faecalis in infected root canals using a special intracanal fiber. Methods: A total of 70 extracted, single-rooted teeth were used. The teeth were decoronated at the length of the roots to approximately 15 mm and then instrumented. The apical foramen was sealed by composite resin, and the root canals were infected with a pure culture of E. faecalis ATCC 29212 for eight days at 37 °C. Following the contamination period, the roots were divided into seven groups, including the positive and negative control groups, and treated as follows: ALAD 45 min; red light activation 7 min; ALAD 45 min and red-light activation 7 min; sodium hypochlorite 2.5% 15 min; sodium hypochlorite 1% 15 min. The samples were taken by three sterile paper points, transferred to tubes containing 1 mL of PBS, and immediately processed for the number of colony-forming units and the cell viability by using live/dead. Results: The best treatment is obtained with 2.5% NaOCl. Except for ALAD + red light vs. 1% NaOCl, a statistically significant difference is recorded for all treatments. The combination of 2.5% NaOCl and ALAD + 7 min irradiation produces an evident killing effect on the E. faecalis cells. On the other hand, 1% NaOCl is ineffective for the viability action, with 25% of dead cells stained in red. Conclusions: This ex vivo study shows that ALAD gel with light irradiation is an efficacious protocol that exerts a potent antibacterial activity against E. faecalis in infected root canals

Correlation between use of different type protective facemasks and the oral ecosystem

Abstract Background Spread worldwide through droplets, the Virus Sars-Cov-19 has caused a global health emergency alarm. In order to limit its spread, the use of masks has become part of the daily life of the entire population, however, little is known about its constant use and the changes generated in the oral cavity. This work aims to investigate correlations between the continuous use of masks covering the nose and mouth for 3 h and changes in the ecological factors of the oral cavity. Methods 34 volunteers were divided into 2 groups: wear only the filtering facepiece code 2 (FFP2) mask (Group A) and wear the FFP2 mask covered by a surgical mask (Group B). Measurement of Volatile Organic Compounds (VOCs), saliva rehydration and consistency test, collection of basal saliva and saliva stimulated with paraffin gum and mucosal swab were collected and analyzed at two times: before using the mask(s) (T0) and 3 h after continuous use of the mask(s) (T1). Results The results indicated a significant difference between the groups, in which the basal saliva volume and pH and the peaks of VOCs increased for group B between T0 and T1. The rehydration time decreased and the volume and pH of the stimulated saliva increased, but with no significant difference between the groups. Furthermore, group B showed a significant decrease in Candida albicans Colony Forming Units (CFUs) and Total Bacterial Count (TBC) between T0 and T1. Conclusion It is concluded that the prolonged use of the FFP2 mask covered by a surgical mask can generate oral alterations in the user

Color evaluation of a resin cement light polymerized by different light sources and submitted to potentially staining beverages

Abstract Introduction The color stability of resin cements, whether dual-pre-cured or photopolymerizable, as well as the color of the dental substrate, are fundamental for the aesthetic success of ceramic restorations, since the ceramic presents a high level of translucency due to its small thickness. Objective The aim of this in vitro study was to evaluate the color of a resin cement light polymerized by different light sources and immersed in potentially staining beverages. Material and method Were made 42 specimens of resin cement Variolink-Esthetic (2×6mm) (n=7), being half polymerized with LED light (F1) and half with Halogen light (F2). The specimens were stored in artificial saliva at 37 °C±1 °C. After 24 hours, they were polished with abrasive discs, and divided for the purpose of being submitted to the different solutions for 2 minutes per day, for 28 days, as follows: S1 – Coca-Cola; S2 – Red Wine; and S3 – Distilled Water (Control). Five color readouts were taken: T0 – initial; T1 – 7 days; T2 – 14 days; T3 – 21 days; and T4 – 28 days; with a spectrophotometer (Model SP62S). The color change data (ΔE*) were submitted to statistical analysis, ANOVA and Tukey (p≤0.05). Result Analyzing the factor solution, S2 (5.89 (±0.02)), produced a higher ΔE* value than S1 (3.79 (±0.02)) and (S1), a higher value than S3 (1.41 (±0.02)). Analyzing the factor light source, F2 (4.05 (±0.12)), produced a higher ΔE* value than F1 (3.33 (±0.12)). When analyzing the factor time, ΔE* values were found to increase gradually over the course of time: T1(2.36 (±0.08)); T2(3.27 (±0.08)); T3(4.06 (±0.08)); and T4(5.09 (±0.08)). Conclusion It was concluded that red wine produced a greater color change; Halogen light promoted highest degree of pigmentation; and the longer the time of immersion, the greater the color change of the material

Strontium Carbonate and Strontium-Substituted Calcium Carbonate Nanoparticles Form Protective Deposits on Dentin Surface and Enhance Human Dental Pulp Stem Cells Mineralization

Strontium acetate is applied for dental hypersensitivity treatment; however, the use of strontium carbonates for this purpose has not been described. The use of Sr-carbonate nanoparticles takes advantage of both the benefits of strontium on dentin mineralization and the abrasive properties of carbonates. Here in, we aimed to synthesize strontium carbonate and strontium-substituted calcium carbonate nanoparticles and test them as potential compounds in active dentifrices for treating dental hypersensitivity. For this, SrCO3, Sr0.5Ca0.5CO3, and CaCO3 nanoparticles were precipitated using Na2CO3, SrCl2, and/or CaCl2 as precursors. Their morphology and crystallinity were evaluated by electron microscopy (SEM) and X-ray diffraction, respectively. The nanoparticles were added to a poly (vinyl alcohol) gel and used to brush dentin surfaces isolated from human third molars. Dentin chemical composition before and after brushing was investigated by infrared spectroscopy (FTIR) and X-ray dispersive energy spectroscopy. Dentin tubule morphology, obliteration, and resistance of the coatings to acid attack were investigated by SEM and EDS. The cytotoxicity and ability of the particles to trigger the mineralization of hDPSCs in vitro were studied. Dentin brushed with the nanoparticles was coated by a mineral layer that was also able to penetrate the tubules, while CaCO3 remained as individual particles on the surface. FTIR bands related to carbonate groups were intensified after brushing with either SrCO3 or Sr0.5Ca0.5CO3. The shift of the phosphate-related FTIR band to a lower wavenumber indicated that strontium replaced calcium on the dentin structure after treatment. The coating promoted by SrCO3 or Sr0.5Ca0.5CO3 resisted the acid attack, while calcium and phosphorus were removed from the top of the dentin surface. The nanoparticles were not toxic to hDPSCs and elicited mineralization of the cells, as revealed by increased mineral nodule formation and enhanced expression of COL1, ALP, and RUNX2. Adding Sr0.5Ca0.5CO3 as an active ingredient in dentifrices formulations may be commercially advantageous since this compound combines the well-known abrasive properties of calcium carbonate with the mineralization ability of strontium, while the final cost remains between the cost of CaCO3 and SrCO3. The novel Sr0.5Ca0.5CO3 nanoparticles might emerge as an alternative for the treatment of dental hypersensitivity