Do bioactive materials show greater retention rates in restoring permanent teeth than non-bioactive materials? A systematic review and network meta-analysis of randomized controlled trials.

OBJECTIVES: To answer the following research question: does the clinical evaluation of restorations on permanent teeth with bioactive materials show greater retention rates than those with non-bioactive materials? MATERIALS AND METHODS: A search strategy was used in the following databases: MEDLINE via PubMed, Scopus, Web of Science, LILACS, BBO, Embase, The Cochrane Library, and OpenGrey. Randomized controlled trials (RCTs), with a minimum of 2-year follow-up and evaluating at least one bioactive material in permanent teeth were included. Risk of bias was detected according to the Cochrane Collaboration tool for assessing the risk of bias (RoB 2.0), and network meta-analysis was performed using a random-effects Bayesian-mixed treatment comparison model. RESULTS: Twenty-seven studies were included. The success of the restorations was assessed using modified USPHS system in 24 studies and the FDI criteria in 3 studies. Network meta-analysis revealed three networks based on restoration preparations. Resin composites were ranked with higher SUCRA values, indicating a greater likelihood of being the preferred treatment for class I, II, and III restorations. In class V, resin-modified glass ionomer cement was ranked with the highest value. CONCLUSION: Bioactive restorative materials showed similar good clinical performance in terms of retention similarly to conventional resin composites. CLINICAL SIGNIFICANCE: The findings must be interpreted with caution because many RCT on restorative materials aim to verify the equivalence of new materials over the gold standard material rather than their superiority. The present systematic review also suggests that new RCT with longer follow-up periods are necessary.

Efficacy of bioactive materials in preventing Streptococcus mutans-induced caries on enamel and dentine.

The study investigated the ability of bioactive materials used to restore enamel and dentine specimens to prevent caries. Enamel (n = 50) and dentine (n = 50) specimens were obtained from bovine incisors, prepared, and randomly allocated to one of five groups according to the restorative treatment: alkasite without adhesive system; alkasite with adhesive system; high viscosity glass ionomer cement; resin composite; no restoration; negative control group. Specimens were restored, exposed to a thermal cycling aging protocol, sterilized, and exposed to a cariogenic challenge induced by Streptococcus mutans and then submitted to surface and subsurface microhardness tests and polarized light microscopy to verify the caries lesion development in enamel or dentine surrounding the restorative materials. Data were analyzed using one-way ANOVA. In enamel and dentine, glass ionomer cement, alkasite without and with adhesive system presented a lower percentage surface microhardness loss than resin composite and negative control. Enamel subsurface microhardness presented no statistically significant differences between glass ionomer cement, alkasite without and with adhesive system. Glass ionomer cement also did not present statistically significant differences from resin composite and the negative control. In dentine, glass ionomer cement showed the highest subsurface microhardness values. In conclusion, bioactive restorative materials provide greater protection to enamel and dentine against surface caries development than resin composite.

Tooth color change promoted by different whitening toothpastes under alternate cycles of staining and brushing.

OBJECTIVES: To compare the effect of whitening toothpastes with different mechanisms of action on discolored teeth subjected to additional staining/or not. METHODS: One hundred twenty tooth specimens were stained for 14 days (staining broth under constant agitation and pH=7) and then allocated into the groups of toothpastes with different whitening ingredients (n=10): 1. Regular - Colgate Total 12 Clean Mint; 2. CLWI - Colgate Luminous White Instant (blue pigment); 3. CLWA - Colgate Luminous White Advanced Expert (hydrogen peroxide); 4. CLWAC - Colgate Luminous White Activated Charcoal (activated charcoal); 5. OB3D - Oral-B 3D WHITE Brilliant Fresh (abrasive); 6. TW - Teeth Whitening (charcoal powder). Specimens were submitted to two experimental models: A. Daily staining-toothbrush cycling: staining solution (5min), toothbrushing (45 strokes) and artificial saliva (3h), 2x/day, for 5 days; B. Only toothbrushing (30.000 brushing strokes). Color change was determined with a spectrophotometer (CIEDE2000 and Whiteness Index for Dentistry - WID) and statistically analyzed (α=0.05). RESULTS: For both models, ΔE00 and Δa did not differ significantly between the whitening toothpastes and the regular. All groups showed a decrease in tooth yellowness (-Δb) and an increase in WID. Group Teeth Whitening exhibited a decrease in luminosity (-ΔL). In model A, Groups did not differ significantly from the Regular in terms of ΔL (p=0.35) and Δb (p=0.74). Groups CLWI and OB3D exhibited a decrease in luminosity. Reduced redness (-Δa) occurred only in Group CLWI. In Model B, Groups OB3D (p=0.021) and CLWA (p=0.001) exhibited higher change in luminosity than in Group Teeth Whitening. All exhibited increased redness (+Δa) and lightness (+ΔL), except the Regular, CLWAC, and Teeth Whitening. Group OB3D had a significantly higher change in Δb than the Regular (p=0.021). CONCLUSIONS: Irrespective of the mechanism of action, all toothpastes reduced tooth yellowness and promoted similar overall color change. Exposure of the teeth to additional staining during the toothbrushing cycles did not influence the effect of the whitening toothpastes. CLINICAL SIGNIFICANCE: Whitening toothpastes should be tested in conditions that more closely simulate their use in a clinical scenario, in which alternate cycles of staining and brushing occur on a daily basis. However, even in such conditions, they were unable to promote a color change that differed from that of a regular toothpaste.

Surface smoothness of resin composites after polishing-A systematic review and network meta-analysis of in vitro studies.

A systematic review and network meta-analysis was performed to provide evidence for the best polishing protocol for different types of resin composites to minimize surface roughness. A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, EMBASE, and Cochrane Library on July 2, 2019 (updated in December, 2020). In vitro studies that included at least two systems for polishing resin composites and analyzed surface roughness were included. The risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare surface roughness in resin composites with the different types of polishers. Surface under the cumulative ranking curve (SUCRA) analysis was performed to rank the probability for the best polishing system. After removal of duplicates, title and abstract screening yielded 34 studies. Network meta-analysis was not possible for hybrid and microhybrid composites. SUCRA analysis showed that abrasive paper discs allowed greater surface smoothness for nanohybrid and nanofill composites to a probability of between 83% and 91.6%. Silicon carbide brush had a 78.2% probability of being the best system for microfill composites. The use of abrasive paper disc polishers showed a favorable result in nanofill and nanohybrid resin composites. Silicon carbide brush has a greater chance of promoting a smoother surface for microfill resin composites.

Effects of lesion size on the 30-month clinical performance of restorations with bulk fill and a regular nanofilled resin composite in noncarious cervical lesions.

OBJECTIVE: The aim of this double-blind, randomized trial was to evaluate the influence of the occlusogingival distance (OGD) in noncarious cervical lesions (NCCLs) on the clinical performance of a regular bulk-fill resin composite and a regular nanofilled resin composite. MATERIALS AND METHODS: One hundred and forty NCCLs in 77 participants were randomly divided into four groups (n = 35), according to OGD (1.5 mm ± 10% or 3 mm ± 10%) and resin composites (Filtek Bulk Fill Posterior [B] or Filtek Z350 XT [C]), namely: 1.5 mm-B, 1.5 mm-C, 3 mm-B, and 3 mm-C. The restorations were bonded using a two-step self-etch adhesive (Clearfil SE Bond), applied following the manufacturer's instructions. Restorations were polished 1 week after placement. Two experienced and calibrated examiners evaluated the restorations using modified US Public Health Service criteria at baseline (7 days) and after 6, 12, 18, 24, and 30 months. Statistical analyses were carried out using Kruskal-Wallis, Friedman's repeated measures analysis of variance, and the Wilcoxon signed rank test (α = 0.05). RESULTS: After 30 months, the recall rate was 94.2%. Eight restorations were lost (3 for 1.5 mm-C, 2 for 1.5 mm-B, 1 for 3 mm-C, and 2 for 3 mm-B). All groups resulted in a significantly worse marginal discoloration and surface texture at 30 months in comparison with the baseline (1 week). No significant difference was found for the other parameters. CONCLUSION: The restorations performed with both resin composites produced clinically acceptable restorations. The OGD of NCCLs did not influence the clinical performance of restorations. CLINICAL SIGNIFICANCE: The OGD of NCCLs did not have a significant effect on the clinical performance of a regular bulk-fill and nanofilled restorations. Both materials showed a very good performance on 30-month evaluation.

In vitro effectiveness of different dental bleaching protocols using violet LED.

PURPOSE: There has been growing demand for dental bleaching worldwide, however, despite being effective, hydrogen peroxide (HP) can negatively affect the dental structure. Thus, new techniques, such as violet LED light have emerged and need to be studied. The aim of this study was to analyze and compare the effectiveness of violet LED light alone or combined with 35% HP gel. METHODS: Six different tooth bleaching techniques (n = 10) were performed in intrinsically pigmented bovine teeth: G1 - 35% HP (1x/week for 4 weeks, 45 min of gel application); G2 - 35% HP (1x/week for 4 weeks, 15 min of gel application); G3 - violet LED (1x/week for 4 weeks); G4 - violet LED (2x/week for 2 weeks); G5 - violet LED (4x/week for 1 week); G6 - Violet LED + 35% HP (hybrid technique, 1x/week for 4 weeks, 15 min of gel application). Specimens were submitted to color evaluation at predetermined times using Konica Minolta® spectrophotometer, and the surface morphology (n = 3) was qualitatively analyzed by Scanning Electron Microscope (SEM). Data of the color change test were analyzed considering a 5% level of significance. RESULTS: There was significant difference in color (p <0.05) for all groups after bleaching protocols. SEM analysis revealed that the greatest change in surface occurred in Group G1, with demineralization of the dental enamel. When considering the same time interval, there were no statistical differences for axis L*, but differences were shown for axis a* (G2, G3, G4 ≥ G1, G5 ≥ G6) and b* (G1, G2, G3, G4, G5 > G6). Regarding the comparison of ΔE00 between groups, results showed statistical difference between groups, with G1 ≥ G2, G5, G6 ≥ G3, G4. CONCLUSION: Bleaching protocols with less time (15 min) or no exposure to 35% HP (violet LED, 4x/week) could promote bleaching results as those obtained by the conventional technique using 35% HP for 45 min, with no enamel surface changes, showing to be a promising alternative to tooth bleaching.

Is the use of Lactobacillus reuteri probiotic efficient as adjunctive therapy in the treatment of periodontitis? A systematic review / O uso do probiótico Lactobacillus reuteri como terapia adjuvante no tratamento da periodontite é eficaz? Uma revisão sistemática

Objective: This systematic review had the purpose to validate the probiotic Lactobacillus reuteri as adjuvant therapy in the periodontal treatment of periodontitis, by the analysis of randomized controlled trial, controlled clinical trial, and observational studies. Material and Methods: Search keys related to the subject were defined, and the following databases were used as search strategies: MEDLINE via PubMed, Scopus, Web of Science, Cochrane Central Controlled Trials Registry, and EMBASE. The data selection and study were performed by two independent evaluators: first, they selected the article by title and abstract and subsequently qualified according to the bias risk analysis. A narrative synthesis has been performed based on the data obtained from the best-quality articles. After data extraction, their heterogeneity was analyzed, and a meta-analysis was performed. Results: In general, the results of the meta-analysis were positive for the use of probiotics as an adjuvant treatment. Considering the limitations of the comparisons between the analyzed articles studied, the conclusion was that probiotics may provide supplementary benefits to the treatment of periodontitis, with improvement in bleeding on probing rates and probing depth (AU)

Objetivo: Esta revisão sistemática teve como objetivo validar o uso do probiótico Lactobacillus reuteri como terapia adjuvante no tratamento periodontal da periodontite, por meio da análise de ensaios clínicos randomizados, ensaios clínicos controlados e estudos observacionais. Material e Métodos: Chaves de busca relacionadas ao assunto foram definidas, e as seguintes bases de dados foram utilizadas como estratégias de busca: MEDLINE via PubMed, Scopus, Web of Science, Cochrane Central Controlled Trials Registry e EMBASE. A seleção dos dados e o estudo foram realizados por dois avaliadores independentes: primeiro, selecionaram o artigo pelo título e resumo e posteriormente qualificaram de acordo com a análise de risco de viés. Uma síntese narrativa foi realizada com base nos dados obtidos dos artigos de melhor qualidade. Após a extração dos dados, sua heterogeneidade foi analisada e uma meta-análise foi realizada. Resultados: Em geral, os resultados da meta-análise foram positivos para o uso de probióticos como tratamento adjuvante. Considerando as limitações das comparações entre os artigos analisados estudados, concluiu-se que os probióticos podem trazer benefícios complementares ao tratamento da periodontite, com melhora nas taxas de sangramento à sondagem e na profundidade de sondagem (AU)

Antimicrobial efficacy of S-PRG containing toothpastes on S. mutans biofilm development / Eficácia antimicrobiana de dentifrícios contendo S-PRG sobre o desenvolvimento de biofilme de S. mutans

Objective: to investigate the antimicrobial effects of toothpastes containing bioactive surface pre-reacted glass particles (S-PRG) on S. mutans biofilms adherence, initial colonization and maturation. Material and Methods: a reference UA 159 and a clinical S. mutans (SM6) strain were used. Bovine enamel specimens were randomly allocated into the groups (n=5): toothpastes containing 0%; 1%; 5%; 20%; 30% S-PRG; positive control dentifrice (NaF+triclosan); and negative control (distilled water). For biofilm development, samples were placed in a 24-well plate containing artificial saliva (4h), followed by adding 1mL of artificial saliva, BHI broth and 225µL of S. mutans suspension. Treatments with toothpastes were applied previously or after 4h and 24h of biofilm formation. Samples were incubated for 48h at 37°C in 5%CO2 and biofilm was detached and seeded in Petri dishes for determining the number of viable cells. Data were analyzed by ANOVA and Tukey test (5%). Results: significantly lower microorganisms' adherence (p<0.05) was obtained for all S-PRG toothpastes, with similar results to NaF+triclosan for SM6 and 20 and 30%S-PRG groups exhibiting higher inhibition effect than the NaF+Triclosan for UA159. Antibacterial effect on the early-stage biofilm was also observed for the S-PRG groups, but was not superior to the NaF+Triclosan toothpaste. For the mature biofilm, the effective antimicrobial potential of S-PRG toothpastes was observed only for the SM6 clinical strain, but was not higher than the positive control. Conclusion: experimental S-PRG toothpastes were effective to inhibit S. mutans biofilm growth by exhibiting antimicrobial activity, being promising agents to prevent cariogenic biofilm development (AU)

Objetivo: investigar o efeito de dentifrícios contendo S-PRG sobre a colonização inicial e maturação de biofilmes de S. mutans. Material e Métodos: uma cepa de referência (UA 159) e uma cepa clínica de S. mutans (SM6) foram utilizadas. Espécimes de esmalte bovino foram alocados nos grupos (n=5): dentifrícios contendo 0%; 1%; 5%; 20% e 30%S-PRG; controle positivo (NaF+triclosan); e controle negativo (água destilada). Os espécimes foram inseridos em uma placa de 24 poços contendo saliva artificial (4h), seguido por adição de 1mL de saliva artificial, BHI, 225µL de suspensão de S. mutans e foram tratados com suspensões de dentifrícios antes ou depois de 4 e 24h da formação do biofilme. Os espécimes foram incubados por 48h e o biofilme foi removido dos espécimes e semeado em placas de Petri para contagem de UFC/mL. Os dados foram analisados por ANOVA e teste de Tukey (5%). Resultados: houve diminuição na adesão de microrganismos para os grupos tratados com S-PRG (p<0.05). Para SM6, os dentifrícios contendo S-PRG apresentaram resultados semelhantes ao NaF+triclosan e para a cepa UA159 o dentifrício com 30%S-PRG apresentou efeito superior. Efeito antimicrobiano no biofilme recém-formado (4h) foi observado para os grupos contendo S-PRG, mas não foi observado efeito superior ao NaF+Triclosan. Para o biofilme maduro, efeito antimicrobiano do S-PRG foi observado apenas para a cepa clínica, mas não superior ao efeito do NaF+Triclosan. Conclusão: dentifrícios contendo S-PRG foram eficazes na inibição do desenvolvimento de biofilmes de S. mutans, sendo promissores agentes para prevenir o desenvolvimento de biofilme cariogênico. (AU)

Influence of different intraradicular chemical pretreatments on the bond strength of adhesive interface between dentine and fiber post cements: A systematic review and network meta-analysis.

Systematic review and network meta-analyses were performed to answer the question: Do intraradicular chemical pretreatments affect the bond strength of the adhesive interface between dentine and fiber post cements? A literature search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, and Cochrane Library in October 2018 (updated September 2021). In vitro studies that compared the bond strength assessed by push-out tests following at least two dentine chemical treatments prior to fiber post cementation were included. Risk of bias was evaluated. A random-effects Bayesian-mixed treatment comparison model was used to compare push-out bond strength of different chemical pretreatments. SUCRA (surface area under the cumulative ranking) analysis was performed to rank the pretreatments. After removing duplicates and screening titles and abstracts, 61 studies remained. SUCRA analysis showed that the best bond strength values for self-etch, etch-and-rinse, and self-adhesive cements were ethyl acetate (SUCRA: 99.8%), low concentration NaOCl (SUCRA: 83.4%), and grape seed extract (SUCRA: 97.6%), respectively. According to the SUCRA rankings, ethanol was in a good position for all adhesive strategies (SUCRA: 78.6%). The use of chemical pretreatments in intraradicular dentine of endodontically treated teeth depends on the adhesive and cementation strategy. The pretreatment generally associated with the highest bond strength was ethanol.

Sintering mode of a translucent Y-TZP: Effects on its biaxial flexure fatigue strength, surface morphology and translucency.

OBJECTIVE: This investigation evaluated the effect of two sintering modes of a translucent zirconia (Y-TZP) on its surface roughness, topography, phase-transformation (t → m), translucency and biaxial flexure fatigue strength. MATERIALS AND METHODS: To do so, 50 Y-TZP discs (Ø = 15 mm; thickness = 1.2 mm; IPS e.max ZirCAD LT) were prepared and divided into two groups: Standard mode (SM) and Fast mode (FM). Staircase fatigue testing was performed (piston-on-three balls set-up, ISO 6872:2015), as well as surface roughness, profilometry, scanning electron microscopy (SEM-FEG), energy dispersive X-ray spectroscopy (EDX), phase transformation (t → m) using X-ray diffraction analysis (XRD), translucency parameter analysis (TP and TP00 ) and fractography. RESULTS: The results showed no statistical significant differences for roughness parameters (p > 0.05, SM: Ra = 0.13 ± 0.02, Rz = 1.21 ± 0.26 and RSm = 24.91 ± 2.19; FM: Ra = 0.14 ± 0.03, Rz = 1.32 ± 0.25 and RSm = 24.68 ± 2.16) or flexural fatigue strength (SM: 512 (464-560) MPa; FM: 542 (472-611) MPa) between the groups. In addition, similarity in surface morphological features (SEM and profilometry), composition and phases (EDX and XRD) was observed between the firing protocols. Fractography showed that the failure origin occurred on the tensile side. Sintering mode did not affect the TP (F = 0.001, p = 0.97) and TP00 (F = 0.12, p = 0.72). CONCLUSIONS: Therefore, the fast-sintering mode is suggested as a viable alternative to the standard mode since it does not influence the evaluated surface morphology, microstructure, fatigue strength and translucency of a translucent monolithic zirconia. CLINICAL SIGNIFICANCE: The fast sintering mode is a viable alternative for zirconia without compromising its topography, microstructure, mechanical performance or translucency.

Effect of intraradicular fiber post on the fracture resistance of endodontically treated and restored anterior teeth: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A fiber post is indicated when there is a significant loss of tooth structure and additional support for the restoration is needed. However, whether the use of a glass fiber post affects the fracture susceptibility of the restored anterior teeth is unknown. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the fracture resistance of endodontically treated and restored anterior teeth and to answer the research question, "Does the use of a fiber post influence the fracture resistance of endodontically treated and restored anterior teeth compared with alternative restorative treatments?" MATERIAL AND METHODS: A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and Embase databases without date and/or language restrictions (updated in July, 2020). In vitro studies comparing the fracture strength of endodontically treated and restored anterior teeth with and without fiber posts were included. The risk of bias was evaluated by using the previous meta-analyses of in vitro studies. The results were presented as standardized mean difference with a 95% confidence interval. Statistical heterogeneity of treatment effects between studies was assessed using the Cochran Q test and the I2 inconsistency test, and values greater than 50% were considered indicative of substantial heterogeneity. RESULTS: After the removal of duplicates and title and abstract screening, 31 studies remained. Seventeen were considered low risk of bias, 10 were medium risk of bias, and 4 were high risk of bias. Meta-analysis comparing control and experimental groups favored the use of a fiber post in endodontically treated teeth with some types of restoration to improve fracture resistance (standardized mean difference= 0.5 [0.08; 0.92]); a glass fiber post was also favored (standardized mean difference=0.92 [0.43; 1.42]); for veneer preparations and teeth with cervical cavities, a fiber post increases the fracture strength (standardized mean difference= 0.74 [0.01; 1.47]; 1.18 [0.35; 2.02], respectively). CONCLUSIONS: The use of glass fiber posts increases the fracture resistance of endodontically treated and restored teeth.

Universal adhesive: the effect of different simulated pulpal pressure fluids and bonding modes to dentin.

The aim of this study was to evaluate the effect of SPP with either fetal bovine serum (FBS) or deionized water (DW) on the bond strength (µTBS) of a Universal adhesive to dentin, in both etch-and-rinse (ER) and self-etch (SE) modes. The kinematic viscosity (cSt) of FBS and DW was measured at 25 °C ± 0.1 ºC. Seventy-two sound human molars were sectioned and randomly divided into three groups according to the SPP conditions: (1) Control (0 cm H2O), (2) SPP (15 cm H2O) with FBS, (3) SPP (15 cm H2O) with DW. Each group was subdivided (n = 10) based on the bonding modes: ER (37% phosphoric acid + ScothBond Universal Adhesive) or SE (ScothBond Universal Adhesive). Samples were then submitted to µTBS. Data were analyzed by Student's t test, two-way ANOVA and Tukey tests (p < 0.05). The cSt results showed that DW (23.59 ± 0.39) had significantly higher values than FBS (22.33 ± 0.06). With regard to SPP, the control group (36.1 MPa) had significantly higher values of µTBS when compared to the SPP using FBS (31.06 MPa) and SPP with DW (26.55 MPa). According to ANOVA, the bonding modes and the interaction of simulated pulpal pressure (SPP) did not statistically influence the results (p < 0.05). The presence of SPP reduced the bond strength of Universal adhesive to dentin. DW during SPP had significantly reduced bonding values when compared to FBS. Bonding strategies were not affected by SPP when evaluated in a short period of time (24 h).

Effect of whitening mouthrinses on color change of stained resin composites / Efeito de enxaguatórios clareadores na alteração de cor de resinas compostas previamente manchadas

Objective: The present study compared the effect of whitening mouthrinses (WM) on the color change of stained resin composites (RC). Material and Methods: Cylindrical specimens (6mm-diameter and 1mm-thickness) were prepared with the following RC (n=60/group): Filtek Z350XT (Z350- methacrylate-based), Admira Fusion (AD- ormocer-based), TPH3 (TPH- methacrylate-based), and Beautifil II (BII- giomer/methacrylate-based). The initial color was assessed with reflectance spectrophotometer using CIE L*a*b* system. The specimens were immersed in staining broth during 14 days, submitted to color evaluation (ΔE1) and randomly allocated in 4 subgroups (n=15), according to WM adopted: Listerine Whitening (LW-2% hydrogen peroxide), Plax Whitening (PW-1.5% hydrogen peroxide), Bromelain/papain (BP-experimental solution), and Deionized water (DW-negative control). The whitening cycle consisted of RC immersion in WM for 1 min and in artificial saliva for 30 min, simulating 12 weeks, and final color assessment was performed (ΔE2). Color change data were analysed by ANOVA and Tukey's tests (α=5%). Results: After staining, TPH showed the lowest ΔE1 values and Z350 showed the highest color change (p=0.001). The whitening effect promoted by LW was significantly higher than color alteration obtained with PW (ΔE2), and BII showed the highest color change values (ΔE2) after whitening cycle. Conclusion: LW exhibited the greatest whitening potential on stained RC, mainly with the Giomer (Beautifill II) and the Ormocer-based (Admira Fusion) materials. Bromelain/papain solution showed no whitening effect on stained RC. (AU)

Objetivo: O presente estudo comparou o efeito de enxaguatórios clareadores (EC) na alteração de cor de resinas compostas (RC) previamente manchadas. Material e Métodos: Espécimes cilíndricos (6mm de diâmetro e 1mm de espessura) foram preparados com as seguintes RC (n=60/grupo): Filtek Z350XT (Z350- metacrilato), Admira Fusion (AD- ormocer), TPH3 (TPH- metacrilato), e Beautifil II (BII- giomer/metacrilato). A cor inicial foi mensurada com espectrofotômetro de reflectância utilizando o sistema CIE L*a*b*. Os espécimes foram imersos em um caldo de manchamento durante 14 dias, submetidos a avaliação de cor (ΔE1) e alocados aleatoriamente em 4 subgrupos (n=15), de acordo com EC adotado: Listerine Whitening (LW-peróxido de hidrogênio a 2%), Plax Whitening (PW- peróxido de hidrogênio a 1,5%), Bromelina/papaína (BP-solução experimental), e Água deionizada (AD- controle negativo). O ciclo clareador consistiu na imersão da RC no EC por 1 min e na saliva artificial por 30 min, simulando 12 semanas, e a cor final foi mensurada (ΔE2). Os dados de alteração de cor foram analisados pelos testes ANOVA e Tukey (α=5%). Resultados: Após o manchamento, TPH apresentou o menor valor de ΔE1 e Z350 apresentou a maior alteração de cor (p=0,001). O efeito clareador promovido pelo LW foi significativamente maior que o obtido com o PW (ΔE2) e BII teve a maior alteração de cor (ΔE2) após o ciclo clareador. Conclusão: LW exibiu maior potencial clareador nas RC manchadas. BII apresentou maior alteração de cor em resposta à ação clareadora de ambos enxaguatórios à base de peróxido de hidrogênio testados.(AU)

The effectiveness of propolis extract in reducing dentin hypersensitivity: A systematic review.

OBJECTIVE: This systematic review was performed to evaluate the effectiveness of propolis on dentin hypersensitivity reduction. DESIGN: The search was conducted in Pubmed, Scopus, Web of science, Latin American and Caribbean Health Sciences Literature data base (Lilacs), Brazilian Library in Dentistry (BBO), Embase, and Cochrane Library aiming to identify relevant randomized clinical trials that evaluated the effect of propolis on dentin hypersensitivity. The Cochrane Collaboration tool was used for assessing the risk of bias. RESULTS: From the total of 63 articles found in the search, six clinical trials were selected. All studies reported that propolis was more effective in reducing hypersensitivity than the placebo. No side effects were observed. CONCLUSIONS: Overall, propolis extract can be considered an effective, safe and low-cost alternative to reduce the dentin hypersensitivity.

Monowave and polywave light-curing of bulk-fill resin composites: degree of conversion and marginal adaptation following thermomechanical aging.

Aim: This study aimed to evaluate the effect of polymerization with either a monowave (MW) or a polywave (PW) light-curing unit (LCU) on the degree of conversion (DC) and marginal adaptation following thermomechanical aging of an ormocer bulk-fill resin composite (RC) (Admira fusion X-tra Bulk Fill - AB), a methacrylate-based bulk-fill RC (Tetric N-Ceram Bulk Fill - TB) and a conventional RC (Tetric N-Ceram - TC). Methods: DC was assessed in five samples of each RC using Fourier transform infrared spectroscopy. For determination of marginal adaptation, standard preparations were made in 60 bovine incisors, divided into three groups, according to the RC. The bulk-fill RC was inserted in a single increment of 4 mm. In contrast, the conventional RC was inserted in three increments. Marginal gap was evaluated after thermomechanical aging. Data were analyzed using a two-way analysis of variance (ANOVA) and Tukey's tests for multiple comparisons (α = 0.05). Results: The two-way ANOVA showed a significant effect (p<.05) of the RC factor but not of the LCU factor. The Tukey test showed that TB had the significantly lowest DC followed by TC, and with AB having the significantly highest DC. For the marginal adaptation, a significant effect was found for the LCU factor and the for the interaction RC × LCU (p<.05). Groups light-cured with PW showed significantly wider marginal gaps than MW. TC presented wider marginal gaps (17.36 µm) when cured with PW than when cured with MW (13.05 µm). The two bulk-fill RC resulted in similar marginal gap formation to each other. Conclusion: The ormocer-based bulk-fill RC showed a higher DC than the methacrylate-based bulk-fill RC but similar marginal adaptation. The LCU, MW or PW, had no significant influence on the DC, and no relevance on the marginal adaptation.

Influence of glass fiber posts on the fracture susceptibility of endodontically treated maxillary anterior teeth with direct veneers: Preliminary results of a randomized clinical trial.

OBJECTIVE: The purpose of this randomized clinical trial was to evaluate the influence of glass fiber posts on fracture susceptibility of endodontically treated maxillary anterior teeth with direct veneers. MATERIALS AND METHODS: Fifty participants had 1 maxillary anterior tooth restored with a direct veneer. They were divided into 2 groups (n = 25) according to the use of intraradicular glass fiber posts. Clinical evaluation was performed at baseline, 6 and 12 months. The treatment success was determined by the absence of tooth fracture. If there was fracture, it was classified according to its extent. Fischer exact test was performed to analyze the criteria among the groups at each evaluation time. Friedman repeated analysis of variance assessed the difference in the performance of each group at three recall times (α = 0.5). RESULTS: For control group, at the 6-month follow-up, one tooth had suffered a catastrophic failure, which resulted in tooth extraction. Fisher statistical analysis showed no significant difference between the cumulative success rate of the groups for the 6 (P > .999) and the 12-month (P > .999) period. Friedman test showed no significant difference among the periods of evaluation (P > .999). CONCLUSIONS: Both groups had a similar success rate for maxillary anterior endodontically treated teeth with direct veneers after 12 months. CLINICAL IMPLICATIONS: Glass fiber post use does not influence the fracture susceptibility of maxillary anterior endodontically treated teeth with direct veneers in the short term.

Bacterial levels and amount of endotoxins in carious dentin within reversible pulpitis scenarios.

OBJECTIVES: the objective of the present exploratory study was to determine bacterial diversity and endotoxin levels in deep carious lesions of teeth presenting symptoms of reversible pulpitis. MATERIALS AND METHODS: Twenty patients with deep carious lesions, reporting clinical symptomatology compatible with reversible pulpitis (n = 10) or not reporting clinical symptomatology (n = 10), were selected. Carious dentin samples were obtained with the aid of sterile and pyrogen-free spoon excavators and harvested in two steps: before and after infected dentin removal. Samples were collected for checkerboard and for kinetic chromogenic LAL assay for determination of microbial profile and quantitation of endotoxin, respectively. Data were analyzed by Mann Whitney for bacteria and two-way ANOVA for endotoxins (5%). RESULTS: No difference on the studied bacteria was detected between the superficial and deep dentin layers. Symptomatic teeth showed greater presence of Lactobacillus species, Capnocytophaga sputigena, and Leptotrichia buccalis. For the endotoxins, symptomatic teeth resulted in greater quantity of endotoxins (p = 0.047), being 4.13 log10 EU/mL/µg dentin and 3.45 log10 EU/mL/µg dentin, for symptomatic and asymptomatic teeth, respectively. Dentin collected in different areas presented similar number of endotoxins (p = 0.139). CONCLUSION: The amount of the studied bacteria does not seem to be related to reported symptomatology of deep carious lesions, while endotoxins quantity is greater in symptomatic scenarios, regardless of the harvesting area. CLINICAL RELEVANCE: The understanding of bacterial amount in reversible pulpitis is important to establish a clinical protocol of treatment.

Nanofilled bis-acryl composite resin materials: Is it necessary to polish?

STATEMENT OF PROBLEM: Manufacturers of the recently introduced nanofilled bis-acryl composite resins no longer recommend polishing to produce interim restorations; however, whether this advice is appropriate is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of the type of interim resin material, polishing procedure, and artificial staining on surface roughness, gloss, and color. MATERIAL AND METHODS: Disk-shaped specimens were prepared from 1 unfilled acrylic resin (Duralay) and 3 bis-acryl composite resins (Structur 3-nanofilled, Systemp C&B-microhybrid, Proviplast-microhybrid). The specimens of each material were assigned to 2 subgroups (n=15): polished and unpolished. Surface roughness (Ra-µm), gloss (UB), and color (ΔE) were analyzed at baseline and after 14 days of artificial staining. Roughness and gloss data were separately analyzed by 3-way ANOVA and color by 2-way ANOVA, followed by the post hoc Tukey test (α=.05). RESULTS: The baseline roughness of all materials was significantly reduced by the polishing procedure, whereas the baseline gloss was increased (P<.001). Only the unpolished Proviplast had a significant increase in Ra values after aging. Structur 3 had higher gloss than Systemp C&B and Proviplast. The acrylic resin had the lowest color change after staining. CONCLUSIONS: The polishing procedure produced smother and glossier surfaces for all the materials tested. The nanofilled bis-acryl composite resin material had higher gloss than the microhybrid bis-acryls tested, but it was not different from the acrylic resin. The 14 days of artificial staining did not promote significant changes in Ra or gloss values, except for Ra in the unpolished Proviplast subgroup, indicating excellent performance of the materials. The acrylic resin had the highest color stability.

A 2-year clinical evaluation of direct and semi-direct resin composite restorations in non-carious cervical lesions: a randomized clinical study.

OBJECTIVES: The purpose of this study was to evaluate the 2-year success of resin composite restorations in non-carious cervical lesions (NCCLs) using the direct or semi-direct techniques. MATERIALS AND METHODS: Thirty volunteers presenting with at least two NCCLs were included. Each participant received one restoration using the direct technique and the other using the semi-direct technique, totaling 60 restorations. Time for completing the treatment was computed. Assessments at baseline, 7 days, and 6, 12, and 24 months were performed using the modified United States Public Health Service criteria. Descriptive analysis was reported as a percentage of successful treatments. For inferential analysis, the Student t test was used to evaluate the differences between extension, depth, and time. The chi-square/Fisher tests were used to compare treatment success after each period (α = 0.05). The results were evaluated by using the Kaplan-Meier survival analysis. RESULTS: Differences were detected regarding mean ± standard deviation time, in which direct and semi-direct procedures were accomplished in 21.8 (± 14.5) and 35.3 (± 19.9) min, respectively. Of the 60 restorations placed, 7 failed in the direct group while 8 failed in the semi-direct group up to 2 years. No differences were detected between restorative protocols. The cumulative survival was 88.5% and 88.4% for the direct technique and semi-direct techniques after 24 months, respectively. CONCLUSION: The tested restorative protocols present similar results for NCCLs within the studied periods. CLINICAL RELEVANCE: The semi-direct technique exhibited clinical performance similar to direct technique for NCCL, demonstrating an alternative for restorations of these lesions.

Effect of glass-fiber post on the biomechanical behavior of teeth with direct veneers / Efeito do pino de fibra de vidro no comportamento biomecânico de dentes com facetas diretas

Objective: This study aimed to evaluate the biomechanical behaviour of endodontically treated teeth with direct veneer that received or not intra-radicular glass fiber post by finite elements analysis. Material and methods: Six models were designed, varying the presence or absence of glass fiber post and the thickness of direct veneer (0.5, 0.7 and 1 mm). Tridimensional models of maxillary central incisors were obtained with CAD software, Rhinoceros 4.0, and transferred to CAE software, ANSYS 17.2, which a 100N load was applied in a 45° on the lingual surface to simulate functional movements. Geometry contacts were bonded, and the structures were isotropic, linear, elastics, and homogeneous. After coherence and convergence analysis of mashes, the chosen fail criterion was the maximum principal stresses. Results: For cement, glass fiber post, the stress distribution was similar independently of glass fiber post presence or veneer thickness. Models with glass fiber post had better stress distribution and lower values of maximum stress for inner dentin and veneers. Veneers with 0.5 and 1 mm had higher stress concentration areas. Conclusions: It can be concluded that glass fiber post is favorable for restored teeth with direct veneers, and very thin or very thick preparations can damage the biomechanical behavior of restorations.(AU)

Objetivo: Este estudo teve como objetivo avaliar o comportamento biomecânico de dentes tratados endodonticamente com faceta direta que receberam ou não pinos de fibra de vidro intrarradicular através de análise de elementos finitos. Material e métodos: Foram desenhados seis modelos, variando a presença ou ausência do pino de fibra de vidro e a espessura da faceta direta (0,5, 0,7 e 1 mm). Modelos tridimensionais de incisivos centrais superiores foram obtidos com o software CAD, Rhinoceros 4.0, e transferidos para o software CAE, ANSYS 17.2, cuja carga de 100N foi aplicada a 45° na superfície lingual para simular movimentos funcionais. Os contatos geométricos foram colados e as estruturas eram isotrópicas, lineares, elásticas e homogêneas. Após análise de coerência e convergência de malhas, o critério de falha escolhido foi a tensão principal máxima. Resultados: Para cimento e pino de fibra de vidro, a distribuição de tensões foi semelhante independentemente da presença do pino de fibra de vidro ou da espessura da faceta. Os modelos com pinos de fibra de vidro apresentaram melhor distribuição de tensão e menores valores de tensão máxima para dentina interna e facetas. Facetas com 0,5 e 1mm apresentaram maiores áreas de concentração de estresse. Conclusões: Pode-se concluir que o pino de fibra de vidro é favorável para dentes restaurados com facetas diretas, e preparações muito finas ou muito espessas podem prejudicar o comportamento biomecânico das restaurações.(AU)