Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros








Intervalo de ano de publicação
1.
J Dent Educ ; 88(6): 872-876, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38356365

RESUMO

PURPOSE: To evaluate the influence of ChatGPT on academic tasks performed by undergraduate dental students. METHOD: Fifty-five participants completed scientific writing assignments. First, ChatGPT was utilized; subsequently, a conventional method involving the search of scientific articles was employed. Each task was preceded by a 30-min training session. The assignments were reviewed by professors, and an anonymous questionnaire was administered to the students regarding the usefulness of ChatGPT. Data were analyzed by Mann-Whitney U-test. RESULTS: Final scores and scores for the criteria of utilization of evidence, evaluation of arguments, and generation of alternatives achieved higher values through the traditional method than with ChatGPT (p = 0.019, 0.042, 0.017, and <0.001, respectively). No differences were found between the two methods for the remaining criteria (p > 0.05). A total of 64.29% of the students found ChatGPT useful, 33.33% found it very useful, and 3.38% not very useful. Regarding its application in further academic activities, 54.76% considered it useful, 40.48% found it very useful, and 4.76% not very useful. A total of 61.90% of the participants indicated that ChatGPT contributed to over 25% of their productivity, while 11.9% perceived it contributed to less than 15%. Concerning the relevance of having known ChatGPT for academic tasks, 50% found it opportune, 45.24% found it very opportune, 2.38% were unsure, and the same percentage thought it is inopportune. All students provided positive feedback. CONCLUSION: Dental students highly valued the experience of using ChatGPT for academic tasks. Nonetheless, the traditional method of searching for scientific articles yield higher scores.


Assuntos
Inteligência Artificial , Educação em Odontologia , Estudantes de Odontologia , Educação em Odontologia/métodos , Humanos , Estudantes de Odontologia/psicologia , Redação , Inquéritos e Questionários , Masculino , Feminino
2.
Clin Oral Investig ; 28(1): 106, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38244108

RESUMO

OBJECTIVES: To evaluate the effect of bromelain associated with Biosilicate on the bond strength (BS) of a universal adhesive system to sound (SD) and caries-affected dentin (CAD), and on the proteolytic activity. MATERIALS AND METHODS: Cavities were prepared in 360 molars, half submitted to cariogenic challenge. Teeth were separated into groups (n=20): Control-No treatment; CHX-0.12% chlorhexidine; NaOCl-5% sodium hypochlorite; Br5%-5% bromelain; Br10%-10% bromelain; Bio-10% Biosilicate; NaOClBio-NaOCl+Bio; Br5%Bio-Br5%+Bio; Br10%Bio-Br10%+Bio. Following treatments, the adhesive system was applied, and cavities were restored. Samples were sectioned into sticks and stored at 37 °C for 24 h, 6 months, and 1 year. Microtensile BS (2-way ANOVA, Bonferroni's test, α=0.05), fracture patterns (SEM), and adhesive interfaces (TEM) were evaluated. Bacterial collagenase assay and in situ zymography were performed. RESULTS: In CAD, Br10% presented higher BS (p=0.0208) than Br5%Bio. Br5% presented higher BS (p=0.0033) after 6 months than after 24 h; and association of treatments, higher BS (p<0.05) after aging than after 24 h. Mixed fractures were the most prevalent. Association of treatments promoted a more uniform hybrid layer with embedded Bio particles. Experimental groups presented lower (p<0.0001) relative fluorescence units than Control. Bromelain, associated or not with Bio, showed collagenolytic degradation. CONCLUSIONS: Bromelain associated with Biosilicate did not affect the BS to SD. In CAD, Br5%Bio decreased immediate BS but had no long-term influence. This association decreased the proteolytic activity. CLINICAL RELEVANCE: Bromelain and Biosilicate may enhance the longevity of adhesive restorations by inhibiting endogenous proteases.


Assuntos
Colagem Dentária , Cárie Dentária , Humanos , Cimentos Dentários/química , Adesivos Dentinários/química , Bromelaínas/farmacologia , Bromelaínas/análise , Teste de Materiais , Dentina , Cerâmica , Resistência à Tração , Cimentos de Resina/farmacologia
3.
J Esthet Restor Dent ; 36(5): 770-777, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38014602

RESUMO

OBJECTIVE: This study evaluated the effect of bromelain and propolis extract on the bond strength (BS) of a universal adhesive system to eroded dentin. MATERIALS AND METHODS: Sixty human molars with exposed dentin were halved, with one half protected by composite resin and the other subjected to erosive treatment followed by remineralization. After the erosive treatment, the composite resin was removed, and the teeth were randomly assigned to three groups (n = 20): Adhesive-Control System; Br-10%; Pr-16%. Following the treatments, composite resin blocks were built on the dentin surfaces and sticks of 0.9 mm2 were obtained and stored in distilled water at 37°C for 24 h and 6 months. After these periods, the sticks underwent bond strength testing and the data were analyzed using 2-way ANOVA, Bonferroni test, p < 0.05. Fracture patterns were observed using light microscope and scanning electron microscopy. RESULTS: Irrespective of the substrate and aging duration, propolis demonstrated higher BS (p < 0.05) compared to the other treatments. Eroded dentin exhibited greater removal of the smear layer and dentinal tubules with a larger diameter than sound dentin, especially when treated with bromelain, resulting in the formation of resin tags. CONCLUSIONS: Propolis consistently promoted the highest bond strength, irrespective of aging or substrate. Eroded dentin treated with propolis, or bromelain exhibited a higher prevalence of non-adhesive fractures and resin tag formation. CLINICAL SIGNIFICANCE: Propolis shows promise for enhancing the longevity of adhesive restorations in eroded dentin due to its ability to promote high bond strength.


Assuntos
Colagem Dentária , Própole , Humanos , Bromelaínas , Adesivos Dentinários/química , Cimentos de Resina/química , Própole/farmacologia , Dentina , Resinas Compostas/química , Resistência à Tração , Teste de Materiais
4.
Braz Dent J ; 34(6): 82-90, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38133095

RESUMO

This study evaluated the efficacy of incorporating different concentrations of bioactive glass-ceramic (Biosilicate) into coconut oil on the remineralizing potential and surface roughness of white spot lesions. Fragments (6 x 6 x 2mm) of bovine teeth were sectioned and initial microhardness (KHN) and surface roughness (Ra) readings were obtained. The samples were submitted to cariogenic challenge to form white spot lesions and were separated into six groups (n=13): 1) Artificial Saliva (AS); 2) Coconut Oil (CO); 3) CO+2% Biosilicate (CO+2%Bio); 4) CO+5% Biosilicate (CO+5%Bio); 5) 2% Biosilicate Suspension (2% Bio) and 6) 5% Biosilicate Suspension (5% Bio). The treatments for 1 cycle/day were: immersion into the treatments for 5 minutes, rinsing in distilled water, and storage in artificial saliva at 37ºC. After 14 days, KHN and Ra readings were taken. The surface roughness alteration ((Ra) was analyzed (Kruskal-Wallis, Dunn's post-test, p<0.05). CO+2%Bio had higher (p = 0.0013) (Ra followed by CO+5%Bio (p = 0.0244) than AS. The relative KHN and remineralization potential were analyzed (ANOVA, Tukey, p<0.05), and 5% Bio treatment presented a higher relative microhardness than all other groups (p>0.05). The remineralizing potential of all the treatments was similar (p > .05). When Biosilicate was added, the pH of the suspensions increased and the alkaline pH remained during the analysis. Biosilicate suspension is more efficient than the incorporation of particles into coconut oil at white spot lesion treatment. In addition to the benefits that coconut oil and Biosilicate present separately, their association can enhance the remineralizing potential of Biosilicate.


Assuntos
Cárie Dentária , Animais , Bovinos , Óleo de Coco , Saliva Artificial , Cárie Dentária/terapia , Cerâmica , Remineralização Dentária
5.
Eur J Oral Sci ; 131(5-6): e12947, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37501189

RESUMO

This study evaluated the effect of pretreatment with limonene and/or biosilicate on the bond strength of a universal adhesive system in self-etch mode to dentin. Occlusal cavities were prepared in 80 human molars and the teeth were randomly allocated to one of four groups (n = 20), according to the pretreatment regimens applied before the adhesive. The pretreatments were (i) Control, no pretreatment, (ii) LIM, 0.5% limonene; (iii) Bio, 10% biosilicate; and (iv) LIMBio, LIM + Bio. After adhesive application and restoration, the specimens were sectioned into sticks, separated, and stored in distilled water at 37°C for 24 h or 6 months. Microtensile bond strength test was carried out and measurements were compared across pretreatment groups and storage times. Fracture patterns and adhesive interfaces were observed. Loss of dry mass was calculated (n = 10). There was no statistically significant difference in the bond strength between the groups and the most prevalent fracture pattern was the non-adhesive. LIM and LIMBio resulted in more open dentinal tubules. LIM and Bio, whether separate or combined, showed particles of those substances, which decreased in size and number after 6 months. All groups lost mass weight after treatment, with no statistically significant differences between them. Limonene and biosilicate pretreatment did not affect the bond strength to dentin of the universal adhesive system, but resulted in more non-adhesive fractures, even after 6 months.


Assuntos
Colagem Dentária , Adesivos Dentinários , Humanos , Adesivos Dentinários/química , Limoneno/farmacologia , Cimentos de Resina/química , Colagem Dentária/métodos , Teste de Materiais , Dentina , Cerâmica , Resistência à Tração
6.
J Esthet Restor Dent ; 35(7): 1144-1151, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37083113

RESUMO

OBJECTIVE: To evaluate the effect of activated charcoal-based (AC) products on color alteration, remineralizing potential and surface roughness of dental enamel. MATERIALS AND METHODS: Bovine incisors were cut into 6 × 6 × 2 mm fragments. Initial color (EasyShade, Vita) and surface roughness (Surfcorder SE1700, Kosakalab) readings were performed. Fragments were separated into five groups (n = 17) according to the treatment: Control: Fluoride toothpaste (Colgate Total 12, Colgate); Charcoal + NaF: AC toothpaste (ACT) with sodium fluoride (Colgate Natural Extracts, Colgate); Charcoal + MFP + n-HA: ACT with sodium monofluorophosphate and nanohydroxyapatite (Black is White, Curaprox); Charcoal: Fluoride-free ACT (ProActive, Hinode); and Charcoal powder: AC powder. Simulated toothbrushing was performed and final color and surface roughness readings were obtained. Fragments were then polished, and initial microhardness (HMV-2, Shimatzu) readings were done. Samples were artificially demineralized and brushed again. Final microhardness readings were taken. Data were statistically analyzed. RESULTS: Fluoride-free charcoal presented the lowest surface roughness alteration (p < 0.05). Charcoal powder had the lowest color change (p < 0.05) and negative values for whiteness index for dentistry alteration. All the groups presented values below whiteness acceptability threshold and negative relative microhardness values. Control showed the highest remineralizing potential (p < 0.05). CONCLUSIONS: ACPs did not produce color alteration different from the fluoride toothpaste, except for Charcoal powder that caused less color change. ACPs caused surface roughness alteration similar to the fluoride toothpaste. ACT with fluoride and AC powder did not have remineralizing potential. CLINICAL SIGNIFICANCE: Activated charcoal-based products (ACP) promise effective tooth whitening and quick results, without teeth damage. In addition, some ACPs contain fluoride in toothpaste composition and promise rehardening potential. However, ACPs are not as effective as other whitening agents and can alter the surface roughness of the enamel. Even if the ACPs contain fluoride or other remineralizing agents, they might be ineffective.


Assuntos
Fluoretos , Cremes Dentais , Animais , Bovinos , Fluoretos/farmacologia , Cremes Dentais/farmacologia , Carvão Vegetal/farmacologia , Esmalte Dentário , Pós/farmacologia , Fluoreto de Sódio/farmacologia , Remineralização Dentária/métodos
7.
Gen Dent ; 71(1): 54-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36592360

RESUMO

Ceramic chipping occurs frequently in veneered all-ceramic crowns, and the decision to repair or replace them depends on many factors. The least invasive method is the intraoral repair. This case report describes a conservative restorative treatment performed on a chipped dental crown. A 59-year-old patient fractured her all-ceramic crown, revealing chipping and debonding of the feldspathic ceramic veneer and exposure of the zirconia framework. The fractured fragment was brought to the dental office. Due to the patient's esthetic concerns about prolonged treatment, it was decided to use the fragment to repair the crown intraorally. The result exceeded the patient's expectations. The intraoral repair of a chipped all-ceramic crown is a conservative and low-cost alternative that allows for immediate restoration of the function and esthetics. It is essential to establish protocols that can support clinician decision-making about the most appropriate clinical treatment, seeking the longevity of the restoration and the dental structure.


Assuntos
Coroas , Porcelana Dentária , Humanos , Feminino , Pessoa de Meia-Idade , Porcelana Dentária/química , Cerâmica/química , Zircônio/química , Protocolos Clínicos , Facetas Dentárias , Falha de Restauração Dentária
8.
Braz. dent. j ; 34(6): 82-90, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1528025

RESUMO

Abstract This study evaluated the efficacy of incorporating different concentrations of bioactive glass-ceramic (Biosilicate) into coconut oil on the remineralizing potential and surface roughness of white spot lesions. Fragments (6 x 6 x 2mm) of bovine teeth were sectioned and initial microhardness (KHN) and surface roughness (Ra) readings were obtained. The samples were submitted to cariogenic challenge to form white spot lesions and were separated into six groups (n=13): 1) Artificial Saliva (AS); 2) Coconut Oil (CO); 3) CO+2% Biosilicate (CO+2%Bio); 4) CO+5% Biosilicate (CO+5%Bio); 5) 2% Biosilicate Suspension (2% Bio) and 6) 5% Biosilicate Suspension (5% Bio). The treatments for 1 cycle/day were: immersion into the treatments for 5 minutes, rinsing in distilled water, and storage in artificial saliva at 37ºC. After 14 days, KHN and Ra readings were taken. The surface roughness alteration ((Ra) was analyzed (Kruskal-Wallis, Dunn's post-test, p<0.05). CO+2%Bio had higher (p = 0.0013) (Ra followed by CO+5%Bio (p = 0.0244) than AS. The relative KHN and remineralization potential were analyzed (ANOVA, Tukey, p<0.05), and 5% Bio treatment presented a higher relative microhardness than all other groups (p>0.05). The remineralizing potential of all the treatments was similar (p > .05). When Biosilicate was added, the pH of the suspensions increased and the alkaline pH remained during the analysis. Biosilicate suspension is more efficient than the incorporation of particles into coconut oil at white spot lesion treatment. In addition to the benefits that coconut oil and Biosilicate present separately, their association can enhance the remineralizing potential of Biosilicate.


Resumo Este estudo avaliou a eficácia da incorporação de diferentes concentrações de vitrocerâmica bioativa (biosilicato) ao óleo de coco no potencial remineralizante e na rugosidade superficial de lesões de manchas brancas. Fragmentos (6 x 6 x 2mm) de dentes bovinos foram seccionados e as leituras iniciais de microdureza (KHN) e rugosidade superficial (Ra) foram obtidas. As amostras foram submetidas ao desafio cariogênico para formação de lesões de manchas brancas e foram separadas em seis grupos (n=13): 1) Saliva Artificial (AS); 2) Óleo de Coco (CO); 3) CO+2% Biosilicato (CO+2%Bio); 4) CO+5% Biosilicato (CO+5%Bio); 5) Suspensão de Biosilicato 2% (2% Bio) e 6) Suspensão de Biosilicato 5% (5% Bio). Os tratamentos de 1 ciclo/dia foram: imersão nos tratamentos por 5 minutos, enxágue em água destilada e armazenamento em saliva artificial a 37ºC. Após 14 dias, foram feitas as leituras de KHN e Ra. A alteração da rugosidade superficial ((Ra) foi analisada (Kruskal-Wallis, pós-teste de Dunn, p<0,05). CO+2%Bio apresentou maior (p = 0,0013) (Ra seguido de CO+5%Bio (p = 0,0244) do que AS. O KHN relativo e o potencial de remineralização foram analisados (ANOVA, Tukey, p<0,05), e o tratamento 5% Bio apresentou uma microdureza relativa maior do que todos os outros grupos (p>0,05). A suspensão de biosilicato é mais eficiente que a incorporação de partículas ao óleo de coco no tratamento de lesões de mancha branca. Além dos benefícios que o óleo de coco e o Biosilicato apresentam separadamente, sua associação pode amplificar o potencial remineralizante do Biosilicato.

10.
J Adhes Dent ; 24(1): 195-202, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416447

RESUMO

PURPOSE: This study evaluated the effect of incorporating different concentrations of biosilicate in an experimental self-etch adhesive (SE). MATERIALS AND METHODS: Biosilicate microparticles (0, 2, 5, and 10 wt%) were incorporated into the primer, and degree of conversion (DC) and wettability were tested (one-way ANOVA, Tukey's test, p < 0.05). The two best concentrations were selected (2% and 5%) for µTBS evaluation. Sound human molars (n=20) were sectioned into quarters and randomly assigned to 4 experimental groups: 1. experimental SE + 0% biosilicate (Exp0%; negative control); 2. experimental SE + 2% biosilicate (Exp2%); 3. experimental SE + 5% biosilicate (Exp5%); 4. AdheSE (Ivoclar Vivadent, positive control). After adhesive application, Filtek Z350 (3M Oral Care) composite was built up incrementally to 5 mm. Each quarter tooth was sectioned into sticks (0.9 mm2) and stored in distilled water (37°C) for 24 h, 6 months, or 1 year. After storage, sticks were submitted to µTBS (0.75 mm/min). The Ca:P ratio was analyzed using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS). Data were analyzed using two-way ANOVA with Bonferroni's correction, with statistical siginificance set at p < 0.05. Fracture patterns were observed under a digital microscope and adhesive interfaces with transmission electron microscopy (TEM). RESULTS: Exp2% presented the highest DC (p < 0.05), Exp5% exhibited the lowest µTBS (p < 0.05), and adhesive failures were predominant in all groups. TEM suggested remineralized areas in Exp2% and to a lesser degree in Exp5%. Exp2% and Exp5% showed a higher Ca:P ratio after aging (p < 0.05). CONCLUSION: The incorporation of biosilicate microparticles can improve the properties of self-etch adhesives. It increased the DC of the experimental adhesive as well as mineral deposition. However, the adhesive properties are concentration dependent, as a higher concentration of microparticles can adversely affect the mechanical properties of an adhesive.


Assuntos
Colagem Dentária , Adesivos Dentinários , Adesivos/farmacologia , Cerâmica , Resinas Compostas/química , Colagem Dentária/métodos , Cimentos Dentários/química , Dentina , Adesivos Dentinários/química , Humanos , Teste de Materiais , Cimentos de Resina/química , Resistência à Tração
11.
Clin Oral Investig ; 26(7): 4805-4816, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35301597

RESUMO

OBJECTIVES: The aim of this study was to evaluate the microhardness of caries-affected dentin and color stability of teeth restored after treatments with silver diamine fluoride (SDF) associated to potassium iodide (KI) and Biosilicate. MATERIAL AND METHODS: Different samples from bovine teeth were obtained. For color readings, 80 cavities (6 mm × 6 mm × 2 mm) were prepared, and for microhardness, teeth were flattened into dentine to obtain 40 samples. All samples were submitted to cariogenic challenge and separated in 4 groups, according to the treatment used: 12% SDF + KI; 38% SDF; Biosilicate and control (no treatment). Cavities were restored with resin-modified glass-ionomer cement (RMGIC, Vitremer, 3 M ESPE) or composite resin (CR, Z350, 3 M ESPE). After restoration, the samples were submitted to thermo-mechanical cycling (TMC) for 1,200,000 cycles. Color readings (EasyShade, Vita) were performed after restorations, after TMC, and 30 days after TMC. Knoop microhardness was evaluated on the planned samples before and after cariogenic challenge, after treatments, and after 30 days. Scanning electron microscopy (SEM) evaluated the dentine surface after treatments. Data were analyzed (ANOVA, Bonferroni, p < .05). RESULTS: The results showed a higher color alteration for RMGIC than CR. The time of analysis was significant (p < .05) for the 12% SDF + KI and control group. There was no difference (p < .05) in microhardness between groups. However, there was evidence of dentin remineralization after treatments. CONCLUSIONS: It was concluded that the samples treated with Biosilicate resulted in a color alteration similar to control. The treatments presented dentin remineralizing potential for microhardness, below the demineralization level, caused by the cariogenic challenge. CLINICAL RELEVANCE: Considering the remineralizing potential presented by Biosilicate, this agent is a promising alternative that overcomes the SDF adverse effects such as tooth staining.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Animais , Bovinos , Cerâmica , Cárie Dentária/terapia , Dentina , Fluoretos Tópicos/farmacologia , Cimentos de Ionômeros de Vidro , Compostos de Amônio Quaternário/farmacologia , Compostos de Prata
12.
J Esthet Restor Dent ; 34(2): 328-334, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-32627389

RESUMO

OBJECTIVE: This study evaluated the influence of over-the-counter agents on the maintenance of color and microhardness of the enamel after home bleaching protocol. MATERIALS AND METHODS: Specimens of bovine teeth (6 × 6 × 2 mm) were prepared, and color (Easyshade, VITA) and microhardness (HMV-2, Shimadzu) readings were performed. All the specimens were bleached using 22% carbamide peroxide (22%CP), except for the control group, and then separated into seven groups (n = 10) according to the interaction of toothpaste (whitening, conventional, and whitening with peroxide) and mouth rinse (whitening and conventional). The study simulated 1 year of toothbrushing (Pepsodent, MAVTEC) and mouth rinse by immersion. After that, final color and microhardness measurements were performed. Data were analyzed by one-way ANOVA, Tukey's test (P < .05). RESULTS: The group submitted to 22%CP + whitening toothpaste + whitening mouth rinse showed higher color maintenance (P < .05) than the control group. The perception of whitening of teeth (ΔWID ) was higher than the color change (ΔE00 ). There was a decrease in microhardness after treatment with 22%CP + conventional toothpaste + whitening mouth rinse. CONCLUSIONS: Over-the-counter products can help with the maintenance of tooth whitening after bleaching with carbamide peroxide; however, special attention should be given since the association of products can also reduce the microhardness of the dental enamel. CLINICAL SIGNIFICANCE: The association between whitening toothpastes and mouth rinses might be beneficial for maintaining color during 1 year after bleaching treatment.


Assuntos
Clareadores , Clareadores Dentários , Clareamento Dental , Animais , Peróxido de Carbamida , Bovinos , Cor , Esmalte Dentário , Peróxido de Hidrogênio , Clareamento Dental/métodos
13.
J Dent ; 106: 103585, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33465450

RESUMO

OBJECTIVES: This study evaluated the effect of propolis associated with Biosilicate on the bond strength (BS) and gelatinolytic activity at the adhesive/dentin interface. METHODS: Occlusal cavities were prepared in 320 human molars. Half of them were submitted to cariogenic challenge. All the teeth were separated into eight groups (n = 20): Control - Adhesive System (Single Bond Universal, 3 MESPE); CHX - 0.12 % Chlorhexidine; Bio - 10 % Biosilicate; P16 - Propolis with low levels of polyphenols; P45 - Propolis with high levels of polyphenols; CHX Bio - CHX + Bio; P16 Bio - P16+Bio; P45 Bio - P45+Bio. The adhesive was applied (self-etch mode) after treatments. Restorations (Filtek Z350, 3 MESPE) were performed and samples sectioned into sticks, separated and stored in distilled water at 37 °C for 24 h, 6 months and 1 year. Microtensile BS (0.5 mm/min) was tested and analyzed (2-way ANOVA, Bonferroni's Test, p < .05 and Weibull analysis). Fracture patterns (VH-M100, Keyence) and adhesive interfaces (SEM, EVO-MA10, ZEISS and TEM, JEM-1010, JEOL) were observed; and biodegradation and in situ zymography performed. RESULTS: P16 presented the highest BS values on sound dentin after 6 months. In caries-affected dentin (CAD), the association of treatments promoted the highest BS after 24 h. Sound dentin obtained significantly higher Weibull modulus than CAD. SEM displayed resin tags in P16, P45 and association of treatments. TEM showed good interaction between adhesive and dentin. According to the in situ zymography and biodegradation assay all natural primers reduced the gelatinolytic activity. P45 presented the lowest biodegradation and enzymatic activity. CONCLUSIONS: Propolis and the association of treatments promoted the highest bond strength results and preserved the dentin. All the experimental groups exhibited low gelatinolytic activity. CLINICAL SIGNIFICANCE: Propolis and the association of treatments with Biosilicate could preserve the dentin substrate and improve the longevity of composite restorations.


Assuntos
Colagem Dentária , Cerâmica , Resinas Compostas , Cimentos Dentários , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Cimentos de Resina , Resistência à Tração
14.
Heliyon ; 6(4): e03871, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32373750

RESUMO

OBJECTIVES: This study evaluated the influence of thermo-mechanical cycling (TMC) on the bond strength (BS) of a universal adhesive system (UAS - Adper Single Bond Universal, 3M ESPE) to dentin treated or not with 0.2% chlorhexidine (CHX). METHODS: Eighty human molars were flattened until reach the dentin and separated into 4 groups according to the bonding protocol: ENR Group: 37% phosphoric acid + 3-step etch-and-rinse adhesive system (ENR); UAS Group: UAS in self-etch mode; ENR + CHX Group: 37% phosphoric acid + CHX + ENR; UAS + CHX Group: CHX + UAS in self-etch mode. After treatments, teeth were restored (Filtek Z350, 3M ESPE). Samples (n = 10) were submitted to aging process: stored in distilled water at 37°C/30 days or TMC (ERIOS - 98N/1.6Hz + thermal cycling 5/37/55 °C - 1,200,000 cycles). Specimens were sectioned into sticks (1.0 mm2) and submitted to the microtensile test (Mechanical Test Machine - 0.5 mm/min). Fracture patterns and hybrid layer integrity were analyzed under Stereomicroscope and Scanning Electron Microscopy (SEM). RESULTS: The BS results (3-way ANOVA, Bonferroni's test, α = 5%) showed that groups treated with CHX presented higher BS values than control groups; significant in all cases (p < .05), except for ENR submitted to TMC (p > .05). When CHX was applied and samples were cycled, UAS revealed higher BS (p < .05) than ENR. After TMC, cohesive fractures increased for UAS, regardless of CHX application. SEM analysis demonstrated different hybridization patterns for the adhesive systems tested. CONCLUSION: The performance of the universal adhesive system used in self-etch mode was better than that of the 3-step etch-and-rinse adhesive system. CLINICAL SIGNIFICANCE: Universal adhesive systems have been developed in order to simplify the dentin hybridization protocol. It is important to determine the longevity of the adhesive interface using these bonding materials after chewing.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA