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1.
Braz. j. oral sci ; 20: e219320, jan.-dez. 2021. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1253013

RESUMEN

Aim: This study analyzed the effect of whitening mouth rinses on water sorption (WS), solubility (SL), color change, and surface roughness of a nanofilled composite. Whitening perceptibility and acceptability (WID) were also studied. Methods: Forty specimens of Filtek Z350XT, shade EA2 were produced and randomly distributed (n=8) to AS ­ artificial saliva (control); LWE ­ Listerine Whitening Extreme; CLW ­ Colgate Luminous White; LCM ­ Listerine Cool Mint; and CP ­ Colgate Plax. They were immersed in the mouth rinses 2x/day, for one minute, during 28 days. The color was assessed using an Easyshade spectrophotometer (CIE-L*a*b* system). Surface roughness (Ra-µm) was measured with three parallel measures, using an RP-200 roughness meter. The WS and SL (µg/mm-3) were analyzed based on the ISO 4049 recommendations. The data were analyzed using one- and two-way ANOVA/Tukey tests (α=0.05). Results: Surface roughness significantly increased after immersion in AS and LCM, with no significant differences between the groups either before or after immersion. The ΔE* was not significantly different between the groups. All substances produced a ΔWID higher than the 50%:50% perceptibility and acceptability thresholds. The WS and SL were not significantly affected by the mouth rinses. Conclusion: Whitening mouth rinses did not affect WS, SL, surface roughness, and color stability of a nanofilled composite, regardless of the presence of ethanol in the composition


Asunto(s)
Color , Resinas Compuestas , Medicamentos sin Prescripción , Blanqueadores Dentales , Antisépticos Bucales
2.
Braz. j. oral sci ; 20: e213641, jan.-dez. 2021. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1254539

RESUMEN

Aim: To review the current literature regarding the bond strength of self-adhesive flowable resin composites (SAFRCs) to tooth structure, comparing the outcomes with conventional flowable resin composites (CFRCs). Methods: PubMed/Medline, EbscoHost and Scopus databases were screened (last update on November 2020) using related Medical Subject Headings (MeSH) and free terms. We included in vitro studies published in English language comparing the bond strength of SAFRCs and CFRCs to enamel and/or dentin from primary and/or permanent teeth. Results: In total, 23 articles were included. Unlike CFRCs, SAFRCs such as Vertise® Flow and Fusio™ Liquid Dentin exhibited statistically lower bond strength to enamel and dentin from permanent teeth. There were limited studies comparing the enamel bond strength of CFRCs and SAFRCs (prior phosphoric acid etching and/or adhesive system use). Also, we found few studies that evaluated the bonding effectiveness of Constic® and other SAFRCs to primary teeth. Conclusions: Current SAFRCs showed low bond strength to permanent teeth, which impedes to recommend them as a reliable alternative to CFRCs. The bonding performance of Constic® on both hard dental tissues should be evaluated on future studies. Also, more evidence assessing the bond strength of SAFRCs to primary teeth and etched enamel is needed


Asunto(s)
Recubrimiento Dental Adhesivo , Resinas Compuestas , Revisiones Sistemáticas como Asunto
3.
Braz. j. oral sci ; 20: e219022, jan.-dez. 2021. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1254545

RESUMEN

Minimally invasive dentistry is based on conservative techniques for the treatment of initial caries lesions, the so-called white spot lesions. One of the conservative maneuvers includes the use of enamel resin infiltrant: a low viscosity material that penetrates the enamel pores to stop lesion progression. Aim: Therefore, this case report aimed to describe the clinical case of a 28-year-old female patient under routine consultation, in which a radiographic examination showed the presence of two incipient caries lesions in the left upper premolars. Methods: The application of a resin infiltrating agent (Icon®, DMG ­ Hamburg, Germany) was chosen as treatment to stop caries lesions progression. Conclusion: The use of this conservative technique can be considered a promising approach for the prevention of dental tissue wear, and the resin infiltrant is considered an effective material


Asunto(s)
Humanos , Femenino , Resinas Compuestas , Caries Dental , Tratamiento Conservador
4.
Braz. j. oral sci ; 20: e212755, jan.-dez. 2021. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1254632

RESUMEN

Aim: To investigate restorative decisions made by dentists and to examine what demographic characteristics are associated with the decisions for managing approximal and occlusal lesions. Methods: A questionnaire was randomly sent to 900 Palestinian dentists. It noted the demographic details of the dentists and the years of experience. The questionnaire evaluated the respondents for their treatment decisions regarding approximal and occlusal carious lesions. The data was analyzed using the IBM SPSS statistics for windows. The associations between gender and years of experience of the respondents and their restorative decisions were assessed. Results: The response rate was 58.2%. For occlusal carious lesions, 93.9% of the respondents would postpone operative treatment until the lesion was in dentine (grade 3 to 5). For approximal lesions, intervention was deemed appropriate by 92.6% of the respondents when there was radiographic evidence of a carious lesion reaching the DEJ or deeper. Around 53% preferred to prepare approximal lesions according to the traditional principles of cavity preparation. For both approximal and occlusal lesions, the participants opted for resin composites. Statistically, there was a significant association between the restorative decisions with the years since graduation and gender. Conclusion: The study showed variations between the treatment decisions of Palestinian dentists. The subjects chose conservative treatment plans but still adhered to traditional learned practices especially when cavity preparation for approximal lesions was concerned. The years since graduation and gender played a significant role in the choice of treatment opted for. Resin composites seemed to be a popular choice for treatment


Asunto(s)
Humanos , Masculino , Femenino , Características de la Población , Encuestas y Cuestionarios , Resinas Compuestas , Pautas de la Práctica en Odontología , Caries Dental , Preparación de la Cavidad Dental
5.
Braz. j. oral sci ; 20: e213981, jan.-dez. 2021. ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1254747

RESUMEN

Aim: To compare the microleakage of Cention N, a subgroup of composite resins with a resin-modified glass ionomer (RMGI) and a composite resin. Methods: Class V cavities were prepared on the buccal and lingual surfaces of 46 extracted human molars. The teeth were randomly assigned to four groups. Group A: Tetric N-Bond etch-and-rinse adhesive and Tetric N-Ceram nanohybrid composite resin, group B: Cention N without adhesive, group C: Cention N with adhesive, and group D: Fuji II LC RMGI. The teeth were thermocycled between 5°-55°C (×10,000). The teeth were coated with two layers of nail vanish except for 1 mm around the restoration margins, and immersed in 2% methylene blue (37°C, 24 h) before buccolingual sectioning to evaluate dye penetration under a stereomicroscope (×20). The data were analyzed by the Kruskal-Wallis and Wilcoxon tests (α=0.05). Results: Type of material and restoration margin had significant effects on the microleakage (p<0.05). Dentin margins showed a higher leakage score in all groups. Cention N and RMGI groups showed significant differences at the enamel margin (p=0.025, p=0.011), and for the latter group the scores were higher. No significant difference was found at the dentin margins between the materials except between Cention N with adhesive and RMGI (p=0.031). Conclusion: Microleakage was evident in all three restorative materials. Cention N groups showed similar microleakage scores to the composite resin and displayed lower microleakage scores compared with RMGI


Asunto(s)
Resinas Compuestas , Filtración Dental , Cementos de Ionómero Vitreo , Tercer Molar
6.
Sensors (Basel) ; 21(11)2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34199673

RESUMEN

Disbond arrest features combined with a structural health monitoring system for permanent bondline surveillance have the potential to significantly increase the safety of adhesive bonds in composite structures. A core requirement is that the integration of such features is achieved without causing weakening of the bondline. We present the design of a smart inlay equipped with a micro strain sensor-system fabricated on a polyvinyliden fluorid (PVDF) foil material. This material has proven disbond arrest functionality, but has not before been used as a substrate in lithographic micro sensor fabrication. Only with special pretreatment can it meet the requirements of thin film sensor elements regarding surface roughness and adhesion. Moreover, the sensor integration into composite material using a standard manufacturing procedure reveals that the smart inlays endure this process even though subjected to high temperatures, curing reactions and plasma treatment. Most critical is the substrate melting during curing when sensory function is preserved with a covering caul plate that stabilizes the fragile measuring grids. The smart inlays are tested by static mechanical loading, showing that they can be stretched far beyond critical elongations of composites before failure. The health monitoring function is verified by testing the specimens with integrated sensors in a cantilever bending setup. The results prove the feasibility of micro sensors detecting strain gradients on a disbond arresting substrate to form a so-called multifunctional bondline.


Asunto(s)
Adhesivos , Resinas Compuestas
7.
J Contemp Dent Pract ; 22(3): 273-277, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34210928

RESUMEN

AIM: The purpose of this study was to evaluate 2% chlorhexidine disinfectant (CHX), chitosan, and octenidine dihydrochloride (as cavity disinfectants) on microleakage in cavities restored with universal self-etch adhesive. MATERIALS AND METHODS: Eighty extracted human permanent premolars were selected. Class V cavities were prepared on the facial surface of each tooth. The teeth were then divided into four groups of 20 teeth each. For the control group after cavity preparation, no disinfectant was applied. The other 3 groups were treated with 0.1% chitosan, 2% CHX, and 0.1% octenidine dihydrochloride (OCT). All the groups were restored with universal adhesive followed by composite resin. The teeth were then immersed in 1% methylene blue dye and were sectioned buccolingually. Microleakage was checked under a stereomicroscope on both occlusal and gingival margins. RESULT: Among all the groups chitosan-treated cavities showed the least microleakage. Chlorhexidine treated cavities showed less leakage as compared to control, OCT group at both the margins. CONCLUSION: Chitosan as a cavity disinfectant improves the sealing ability of the self-etch adhesive. Furthermore, in vivo studies need to be conducted to examine the interaction and long-term effect of chitosan with the other self-etch adhesive systems. CLINICAL SIGNIFICANCE: Chitosan a natural polysaccharide can be used as a cavity disinfectant as it improves the sealing ability of self-etch adhesive.


Asunto(s)
Filtración Dental , Desinfectantes , Resinas Compuestas , Preparación de la Cavidad Dental , Cementos Dentales , Filtración Dental/prevención & control , Restauración Dental Permanente , Recubrimientos Dentinarios , Humanos , Cementos de Resina
8.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207218

RESUMEN

Resin-based composite materials have been widely used in restorative dental materials due to their aesthetic, mechanical, and physical properties. However, they still encounter clinical shortcomings mainly due to recurrent decay that develops at the composite-tooth interface. The low-viscosity adhesive that bonds the composite to the tooth is intended to seal this interface, but the adhesive seal is inherently defective and readily damaged by acids, enzymes, and oral fluids. Bacteria infiltrate the resulting gaps at the composite-tooth interface and bacterial by-products demineralize the tooth and erode the adhesive. These activities lead to wider and deeper gaps that provide an ideal environment for bacteria to proliferate. This complex degradation process mediated by several biological and environmental factors damages the tooth, destroys the adhesive seal, and ultimately, leads to failure of the composite restoration. This paper describes a co-tethered dual peptide-polymer system to address composite-tooth interface vulnerability. The adhesive system incorporates an antimicrobial peptide to inhibit bacterial attack and a hydroxyapatite-binding peptide to promote remineralization of damaged tooth structure. A designer spacer sequence was incorporated into each peptide sequence to not only provide a conjugation site for methacrylate (MA) monomer but also to retain active peptide conformations and enhance the display of the peptides in the material. The resulting MA-antimicrobial peptides and MA-remineralization peptides were copolymerized into dental adhesives formulations. The results on the adhesive system composed of co-tethered peptides demonstrated both strong metabolic inhibition of S. mutans and localized calcium phosphate remineralization. Overall, the result offers a reconfigurable and tunable peptide-polymer hybrid system as next-generation adhesives to address composite-tooth interface vulnerability.


Asunto(s)
Antibacterianos/química , Cementos Dentales/química , Proteínas Citotóxicas Formadoras de Poros/química , Antibacterianos/farmacología , Resinas Compuestas/química , Resinas Compuestas/farmacología , Cementos Dentales/farmacología , Metacrilatos/química , Proteínas Citotóxicas Formadoras de Poros/farmacología , Streptococcus mutans/efectos de los fármacos , Remineralización Dental/métodos
9.
J Biol Regul Homeost Agents ; 35(3 Suppl. 1): 213-218, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34289681

RESUMEN

The loss of dental substance due to the presence of decay, to wide conservative repairs, to the preparation of prosthetics or to enamel-dentine fractures, often causes an important structural weakening in the element that is endodontically treated (1-15). It is therefore necessary to use endocanal posts in the coronal reconstruction. Mineral fibre posts and epoxy resins that are available at present, fixed with resinous cements, thanks to their excellent integration, exceed the concept of reconstruction, meant as assembly of heterogeneous materials, arranging homogeneous materials according to a similar flexibility module (16-18). This allows to get a "post dentine cement monobloc", which is ideal for the morphofunctional tooth resetting (19-35). The aim of our experimental study was to analyse and compare the surface characteristics of same posts that are available at present by observing them in their relationship with cement and dental materials (36-44).


Asunto(s)
Cementación , Técnica de Perno Muñón , Resinas Compuestas , Vidrio , Ensayo de Materiales , Estrés Mecánico , Propiedades de Superficie
10.
J Adhes Dent ; 23(4): 297-308, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34269540

RESUMEN

Different kinds of interactions between the restorative material and mineralized dental tissues result in secondary caries around dental composites. Of these, the mechanical interactions have to be carefully investigated. Due to the elastic mismatch between dental tissues and the composite restoration, complex stresses and strains develop at their interface. This complex mechanical environment disturbs the demineralization-remineralization equilibrium of dental hard tissues. The fluid flow both over and within enamel and dentin, associated with their complex ultrastructure and mechanical behavior, is a key factor. It is known that external mechanical loading can indirectly promote the dissolution of enamel and dentin through a pumping action of cariogenic fluids in and out of microgaps at the interface between mineralized tissues and composite. Mechanical loading can also directly influence the physicochemical behavior of dental hard tissues by inducing complex strain and stress fields on the crystal scale. It is important to consider both the direct and indirect paths by which mechanical loading can influence the apatite dissolution kinetics. Therefore, a systematic approach should be used to investigate the mechanism of secondary caries formation considering the tooth-composite interface as a unique complex in which each element has an influence on the other.


Asunto(s)
Resinas Compuestas , Caries Dental , Caries Dental/etiología , Susceptibilidad a Caries Dentarias , Esmalte Dental , Materiales Dentales , Restauración Dental Permanente , Dentina , Humanos
11.
J Adhes Dent ; 23(4): 327-334, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34269543

RESUMEN

PURPOSE: The effect of surface moisture on bur-cut dentin on the microtensile bond strength (µTBS) of universal adhesives with various contents of 2-hydroxyethyl methacrylate (HEMA) and methacrylamide monomers was evaluated. MATERIALS AND METHODS: Flat mid-coronal dentin surfaces of human molars were exposed, and a standardized smear layer was prepared using a fine-grit diamond bur. The surfaces were either left wet or air dried for 10 s before bonding with Clearfil Universal Bond Quick (UBQ), experimental UBQ without an amide monomer (UBQexp), Scotchbond Universal (SBU), Prime&Bond Universal (PBU), or BeautiBond Universal (BBU). The specimens were built up with resin composite, sectioned into sticks and subjected to the µTBS test after 24 h or 10,000 thermal cycles. The µTBS data were analyzed using three-way ANOVA followed by pairwise comparisons with Bonferroni's correction (α = 0.05). RESULTS: The level of dentin moisture did not significantly affect µTBS of UBQ and BBU (p > 0.05). HEMA-containing UBQ, UBQexp, and SBU exhibited higher µTBS to dry dentin, while HEMA-free PBU and BBU showed higher µTBS to wet dentin. Thermocycling significantly decreased the µTBS of UBQexp (p < 0.01) and BBU (p < 0.001) irrespective of dentin moisture level, while SBU was significantly affected only on dry dentin (p < 0.001). Thermocycling had no significant effect on UBQ and PBU containing methacrylamide monomers (p > 0.05). CONCLUSION: Dry surfaces enabled obtaining optimal bonding for HEMA-containing adhesives to bur-cut dentin, while wet surfaces enabled optimal bonding for HEMA-free adhesives. Methacrylamide monomers could contribute to the improvement of the initial and long-term bonding performance of universal adhesives to bur-cut dentin.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Acrilamidas , Adhesivos , Resinas Compuestas , Cementos Dentales , Dentina , Humanos , Ensayo de Materiales , Metacrilatos , Cementos de Resina , Resistencia a la Tracción
12.
J Adhes Dent ; 23(4): 357-365, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34269546

RESUMEN

PURPOSE: This study evaluated whether active application of self-etching adhesives would influence their microtensile bond strength (µTBS) to dentin cut with burs of different grit sizes. MATERIALS AND METHODS: Eighty-four human premolars were divided into 12 groups according to 1) two dentin surface preparations with either superfine- or regular-grit diamond burs; 2) three adhesives - Clearfil SE Bond 2 (SE2), Scotchbond Universal (SBU, 3M Oral Care) and G-Premio Bond (GPB, GC); and 3) two application modes of each adhesive (active or passive). Six bonded teeth per group were sectioned into sticks for µTBS testing. Statistical analyses were performed using 3-way ANOVA followed by Duncan's test (p < 0.05). Additional teeth were prepared to observe the interaction between the dentin smear layer obtained from each bur with adhesives under different application modes using transmission electron microscopy (TEM). RESULTS: Active application significantly increased the dentin bond strength of SE2, irrespective of the kind of bur used (p < 0.05). The highest bond strength of SBU was observed when bonded to superfine-grit diamond bur-cut dentin with the active application. There was, however, no influence of the tested factors on GPB group (p > 0.05). TEM observation showed that active application promoted dentin smear layer dissolution in all adhesive groups. CONCLUSIONS: Bond strengths of self-etching adhesives to dentin are influenced by bur-cut smear layers and mainly by application mode of adhesive materials. Active application improves µTBS of self-etching adhesives by enhancing smear layer modification and resin penetration into bur-cut dentin.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Adhesivos , Resinas Compuestas , Cementos Dentales , Dentina , Humanos , Ensayo de Materiales , Cementos de Resina , Propiedades de Superficie , Resistencia a la Tracción
14.
Br Dent J ; 231(1): 43-48, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34244647

RESUMEN

Introduction A retrospective cross-sectional study of early patient-reported failures of restorations was initiated to understand the reasons and factors associated with early failure. Early patient-reported failures are defined as restorations requiring replacement within three months of placement.Aim To investigate if restorative material placed or any other tooth/restoration/patient factors may be associated with early patient-reported failures.Methods In total, 360 restorations were replaced from January 2016 to December 2017. Multivariable analyses (logistic regression model) were used to identify any patient/tooth/restoration factors that were associated with early patient-reported failures.Results Dislodgement, fracture and pain/sensitivity were the three main failure modes. There was significant association between restorative material type and dislodgement and restoration fracture. The odds of dislodgement for composite resin (CR) were 4.3 times higher compared to amalgam. The odds of dislodgement for glass-ionomer cement (GIC) and resin-modified GIC were 3.7 times higher compared to amalgam. The odds of fracture for CR were ten times lower compared to amalgam. The odds of pain for teeth with a history of restoration failure for a particular tooth were five times lower compared to no history of restoration failure for a particular tooth.Conclusions Restorative material type affected patient-reported failures.


Asunto(s)
Caries Dental , Restauración Dental Permanente , Resinas Compuestas , Estudios Transversales , Amalgama Dental/efectos adversos , Atención Odontológica , Fracaso de la Restauración Dental , Cementos de Ionómero Vitreo , Humanos , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos
15.
J Contemp Dent Pract ; 22(4): 342-348, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34267000

RESUMEN

AIM AND OBJECTIVE: The purpose of this study was to investigate the fracture resistance of marginal ridges restored using different techniques (amalgam, open sandwich technique, and incremental placement) and to compare these with smart dentin replacement (SDR) bulk-fill. MATERIALS AND METHODS: Amalgam, dispersalloy; a nanohybrid resin composite (Tetric N Ceram), a resin-modified glass ionomer cement (RMGIC) base (Fuji II LC), and flowable bulk-fill composites (SureFil SDR) were used. Standardized class II (occluso-distal) OD cavities were prepared on 60 (n = 12) extracted premolars, and five different protocols were used to restore the teeth: group 1, dispersalloy; group 2, dispersalloy with 4 mm Fuji II LC base; group 3, incrementally placed Tetric N Ceram; group 4, Tetric N Ceram with 4 mm Fuji II LC base; and group 5, Tetric N Ceram with SureFil SDR. The restorations were thermocycled then fractured using a universal testing machine, the maximum fracture load of the specimens was measured (N), and the type of fracture was recorded. Statistical analysis was carried out using one-way analysis of variance. RESULTS: Amalgam groups showed the lowest fracture resistance, with no significant difference between the based and nonbased groups. The highest fracture resistance was displayed by Tetric N Ceram with SDR base, and it was significantly higher than all the groups except the Tetric N Ceram nonbased group. The RMGIC based Tetric N Ceram displayed intermediate fracture resistance. The majority of the restorations showed mixed types of fracture except for nonbased amalgam, which mostly failed cohesively through amalgam. SDR-based composite was the only group that showed severe tooth failures. CONCLUSIONS: The use of a 4 mm thick RMGIC base had no detrimental effect on the fracture resistance of class II amalgam and composite restorations. CLINICAL SIGNIFICANCE: Bulk-fill SureFil SDR placed under a conventional resin-based composite had similar fracture resistance to incrementally placed composite but higher than amalgam and composite restorations based on RMGIC.


Asunto(s)
Restauración Dental Permanente , Laboratorios , Diente Premolar , Resinas Compuestas , Materiales Dentales , Cementos de Ionómero Vitreo , Ensayo de Materiales
16.
J Contemp Dent Pract ; 22(4): 353-356, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34267002

RESUMEN

AIM AND OBJECTIVE: To compare between mineral trioxide aggregate (MTA) mixed with water and water-based gel regarding shear bond strength with resin-modified glass ionomer cement (RMGIC) and composite. METHODS AND MATERIALS: In this study, 40 blocks of cylindrical shape were prepared with acrylic. These blocks were divided into four groups with each group consisting of 10 blocks: group-1A: MTA + distilled water + composite, group-1B: MTA + distilled water + RMGIC, group-2A: MTA + polymer + composite, and group-2B: RMGIC + MTA + polymer. After that, a universal testing machine was used for the measurement of shear bond strength. The acrylic blocks were placed under this machine. A blade with a knife-edge was used to provide a crosshead speed of 1 mm/minute. This was continued till bond of MTA in both forms (distilled water/gel) and restorative material failed. RESULTS: It was observed that a statistically significant difference was found between MTAw + composite and MTAg + composite resin but no statistically significant difference between MTAw + RMGIC and MTAg + RMGIC with p ≥ 0.05. It was found that a statistically significant difference was present between the RMGIC and composite groups within the same MTA type with p ≤ 0.05. CONCLUSION: It was concluded from the present study that MTA with a water-based gel has a better shear bond strength than composite resin and RMGIC materials. CLINICAL SIGNIFICANCE: It has been found that MTA has different properties when it is mixed with polymer and water. Very few studies have been conducted in the past to compare MTA mixed with water and water-based gel regarding the shear bond strength with RMGIC and composite.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos de Ionómero Vitreo , Compuestos de Aluminio , Compuestos de Calcio , Resinas Compuestas , Combinación de Medicamentos , Ensayo de Materiales , Óxidos , Resistencia al Corte , Silicatos , Agua
17.
J Contemp Dent Pract ; 22(2): 111-116, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34257167

RESUMEN

AIM: To compare the color change of three flowable composites after exposure to staining solutions. MATERIALS AND METHODS: A total of 240 oval samples were constructed of conventional flowable resin composite, self-adhesive flowable resin composite, and nanohybrid flowable ormocer (n = 80). Each set was further subcategorized into three subsets as regards staining solution. The baseline color parameters were recorded using spectrophotometer after the immersion of the specimens in artificial saliva for 24 hours. Then, the measurements were taken again after exposure to staining solutions where the color change was measured as ΔE* = V (ΔL*2 + Δa*2 + Δb*2). RESULTS: Conventional flowable resin composite had the best color stability in all staining solutions. The coffee was concluded to be the most staining solution. Compared to beverages, mouthwashes had a greater discoloration effect on nanohybrid flowable ormocer than on selfadhesive flowable composite. CONCLUSION: Conventional flowable composite had the highest color stability among the tested materials, followed by flowable nanohybrid ormocer, and the least was self-adhering flowable composite. Coffee had the greatest discoloration effect, followed by a sports drink and then the energy drink. However, mouthwashes did not have a significant discoloration effect. CLINICAL SIGNIFICANCE: Selection of flowable composite materials that are resistant to staining by coffee, beverages, or mouthwashes is an important factor that may influence the sustainability of the esthetic quality of the restoration.


Asunto(s)
Resinas Compuestas , Materiales Dentales , Café , Color , Ensayo de Materiales , Cerámicas Modificadas Orgánicamente , Espectrofotometría , Propiedades de Superficie
18.
J Contemp Dent Pract ; 22(2): 122-127, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34257169

RESUMEN

AIM: The aim of this study is to compare the effectiveness of polymerization of nanohybrid composite resins with different colors and thicknesses, photocured by units of different wavelengths through Knoop microhardness (KHN) and Berkovich nanohardness (DUH). MATERIALS AND METHODS: One hundred twenty specimens of Tetric N-Ceram (Ivoclar/Vivadent) were divided into groups (n = 5) according to the experimental test, the color of the composite resin (A2 and Bleach-M/BM), the light source: monowave (Elipar™ FreeLight DeepCure-3M/ESPE), dental products-1200 mW/cm2/15 seconds (FL); or polywave (Bluephase-Ivoclar/Vivadent 1200 mW/cm2/15 and 30 seconds (BP), and thickness (irradiated surface,1, 2, and 3 mm). The specimens were stored dry for 24 hours at 37°C and received five indentations on the top and button surfaces. Analysis of variance (ANOVA), Tukey, and Pearson correlation (p < 0.01%) tests were used. RESULTS: A direct correlation was found between KHN and DUH. The higher values of KHN and DUH were observed with Elipar™ FreeLight DeepCure unit in irradiated surface and 1-mm-thick specimens at A2 color. CONCLUSION: That Elipar™ FreeLight DeepCure unit showed better effectiveness in curing nanohybrid composite resins, used in this work, in different colors and depths as compared to Bluephase in both experimental tests, and that DUH can substitute KHN test when comparing the effectiveness of polymerization. CLINICAL SIGNIFICANCE: The evaluation of the mechanical properties of composite resins is essential to verify their possible clinical performance.


Asunto(s)
Resinas Compuestas , Luces de Curación Dental , Dureza , Ensayo de Materiales , Polimerizacion , Propiedades de Superficie
19.
Int J Esthet Dent ; 16(3): 280-299, 2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34319664

RESUMEN

The injectable composite resin technique is a minimally invasive and purely additive procedure that uses a transparent silicone index and flowable composite resin to translate the restorative plan from the wax-up to the final restoration. Its minimally invasive nature means that it can preserve tooth structure as it may not require hard tissue reduction. It is also an indirect/direct molding technique that allows the clinician to perform a direct restoration based on a proper analysis and planning. This case report describes a simple case of reshaping the maxillary lateral incisor and maxillary first premolar of a 25-year-old female patient to close the buccal corridor and restore smile symmetry. Digital planning was used to make a biocopy of the contralateral incisor to mimic the restoration. A printed model was prepared based on the design of the digital wax-up, followed by an analog protocol. Shade selection was challenging due to the high translucency of the incisal edges. This article is a step-by-step description of the injectable composite resin technique. It also compares this technique with other treatment options such as ceramic veneers, prefabricated composite veneers, different molding techniques, and freehand bonding. The significant advantages of the injectable composite resin technique include its predictability, repeatability, simplicity, minimal invasiveness, and financial affordability for patients. Recent studies demonstrate significant improvements in physical, mechanical, and optical properties of specific flowable composite resins, which reinforces the justification for implementing them in different restorative procedures.


Asunto(s)
Resinas Compuestas , Coronas con Frente Estético , Adulto , Cerámica , Restauración Dental Permanente , Femenino , Humanos , Incisivo , Sonrisa
20.
J Appl Oral Sci ; 29: e20200467, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34320117

RESUMEN

BACKGROUND: Camphorquinone is the most conventionally used photoinitiator in Dentistry. Although different alternative photoinitiators have been proposed, no photoinitiator was capable of completely substituting camphorquinone. The combination of photoinitiators has been considered the best alternative. OBJECTIVES: To evaluate the effect of combining Norrish type I and II photoinitiators on the cure efficiency of dental resin-based composites. METHODOLOGY: Experimental composites were produced containing different photoinitiator systems: Norrish type I-only, mono-alkyl phosphine oxide (TPO); Norrish type II-only, camphorquinone (CQ); or its combination, CQ and TPO, in a 1: 1 molar ratio. UV-vis absorption spectrophotometry was performed to assess the consumption of each photoinitiator after curing (n=3). A multi-wave LED (Bluephase® G2, Ivoclar Vivadent) was pre-characterized and used with a radiant exposure of 24 J/cm2. The degree of conversion was evaluated by Raman spectrometry, and the elution of the monomers by nuclear magnetic resonance analysis (n=3). Data were analyzed using ANOVA and Tukey's test (α=0.05; ß=0.2). RESULTS: The combination of CQ and TPO increased the consumption of the photoinitiator system compared to CQ-only (p=0.001), but presented similar consumption compared to TPO-only (p=0.52). There was no significant difference in the degree of conversion between the composites regardless of the photoinitiator system (p=0.81). However, the elution of the monomers was reduced when both photoinitiators were combined. TPO-based material presented the highest elution of monomers. CONCLUSIONS: The combination of the photoinitiator systems seems to be beneficial for the cure efficiency of dental resin-based composites.


Asunto(s)
Resinas Compuestas , Fotoiniciadores Dentales , Color , Ensayo de Materiales , Espectrofotometría
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