Gen Dent
October 2024
The purpose of this study was to evaluate the influence of simplified ceramic surface treatments on the microshear bond strength (μSBS) of 2 resin cements to a zirconia-reinforced lithium silicate (ZLS) material. Blocks of ZLS were sectioned to obtain a total of 90 specimens (1.5 mm thick), which were assigned to 9 different surface treatment protocols (n = 10).
View Article and Find Full Text PDFThis research analyzed the effect of the manufacturing method on the flexural strength and color stability of 3D-printed resins used for producing indirect restorations. For this, two dental restorative biocompatible resin materials, OnX (OnX, SprintRay) and CB (Crown and Bridge, Dentca), were divided into 2 groups according with manufacturing method (printed with a Pro95 3D printer - SprintRay; and not printed, with samples obtained with the fluid resin being poured on PVS molds for further light activation in the post-curing process), and subdivided into 2 groups according to the post-curing method: VG (Valo Grand, Ultradent Products) for 120 s and PC (Procure 2, SprintRay). Bar-shaped samples were used to evaluate the flexural strength 24 h after storage in distilled water at 37 °C using a universal testing machine.
View Article and Find Full Text PDFObjectives: To evaluate the effect of different ratios of Bis-EMA/Bis-GMA resin mixtures on the inherent viscosity and curing-related properties: including degree of cure (DC%), shrinkage strain, Knoop micro-hardness (KH) and flexural strength of resin-impregnated fiber-bundles.
Methods: Bis-EMA/Bis-GMA monomers were mixed (by weight) in the following ratios: M1 = 30 %/70 %, M2 = 50 %/50 %, M3 = 70 %/30 %, and M4 = 100 %/0 %. Standard measurements were made of refractive index, viscosity, degree of conversion, shrinkage strain and Knoop hardness (KHN).
Patients are always looking for conservative, esthetic, and long-lasting dental restorations, and the technique used directly influences the longevity of the treatment. The location of the restoration in the mouth and the extent of the decay influence the treatment choice. The larger the dimensions of the cavity preparation, the greater the difficulties in restoring the tooth using direct techniques.
View Article and Find Full Text PDFThis research assessed the effects of pre-heating on the physical-mechanical-chemical properties of different resin composites. For this, resin composites were evaluated in 6 levels: Admira/ADM, Vitra/VIT, Filtek Supreme/FS, Filtek Supreme Flowable/FSF, Filtek One/FO, and Filtek Bulk Fill Flowable/FBF; temperature was evaluated in 4 levels using a composite heater: room temperature/22 ºC, 37 ºC, 54 ºC, and 68 ºC. Response variables were: degree of conversion/DC, flexural strength/FS and color stability/ΔE (immediately after light curing/LC, after 7 days of dark-dry-storage, and after 24 h and 3 days of artificial aging in water at 60 ºC).
View Article and Find Full Text PDFBackground: This paper analyses the effects of root canal fragility and irrigation on external temperature change (ΔT) of different sections of roots during post-space preparation.
Material And Methods: Forty endodontic treated human premolars were evaluated. Roots were divided into four groups based on their root wall thickness (fragile or non-fragile), and whether they received irrigation (yes or no) during post-space preparation.
Determining the appropriate technique for diastema closure is challenging, and the decision must be evidence based. The objective of these case reports is to describe different approaches to diastema closure using direct and indirect techniques, focusing on the characteristics of the patient and clinical requirements to guide treatment. In the first case, a 16-year-old patient had multiple diastemas in the maxillary anterior dentition.
View Article and Find Full Text PDFObjective: This case report described the use of a stamping technique associated with a bulk fill composite to restore an ICDAS 4 carious lesion on a posterior tooth. The 4-year follow-up is also presented.
Clinical Considerations: A 32-year-old patient presented a carious lesion on tooth 36 with an underlying dark shadow at the dentin seen from the noncavitated enamel occlusal surface, which was compatible with an ICDAS 4 carious lesion.
Dent Mater
August 2022
Objective: This study evaluated the microshear bond strength of a resin cement to Y-TZP after different methods of TiO nanotubes (nTiO) incorporation on pre-sintered Y-TZP surfaces.
Methods: nTiO were synthesized and incorporated on Y-TZP slices as follows (n = 15): 1) nTiO mixed with isopropyl alcohol/manual application (MAl); 2) nTiO mixed with acetone/manual application (MAc); 3) nTiO mixed with isopropyl alcohol/high-pressure vacuum application (HPVAl); 4) nTiO mixed with acetone/high-pressure vacuum application (HPVAc). As controls, surfaces were sandblasted with AlO (OX) or Rocatec silicatization (ROC).
Biomater Investig Dent
April 2022
J Clin Exp Dent
February 2022
Background: Provisional materials must have enough strength to withstand masticatory loads without suffering deformation or fracture, and their surfaces must have good finishing and polishing characteristics to reduce biofilm accumulation. Thus, the purpose of this study was to investigate the best polishing protocol for different bis-acryl composite resins in comparison with a conventional resin composite and a self-curing acrylic resin aiming to obtain a smooth restoration surface and resistance to wear.
Material And Methods: One hundred and four samples (15 mm length x 5 mm width x 4 mm depth) were prepared and divided into four groups according to the material tested: Protemp 4 and Structur 3 bis-acryl composite resins, Dencor self-curing acrylic resin, Filtek Z350XT conventional composite resin.
Dent Mater
December 2020
Objective: To evaluate the influence of the addition of functionalized and non-functionalized TiO nanostructures on properties of a resin composite.
Methods: TiO nanostructures were synthesized and functionalized, using 3-(aminopropyl)triethoxysilane (APTMS) and 3-(trimethoxysilyl)propyl methacrylate (TSMPM). Characterizations were performed with XRD, EDS, TEM, and TGA.
The aim of this research was to evaluate the influence of MDP (10-methacryloyloxydecyl dihydrogen phosphate) concentration and application mode of experimental adhesives on microshear bond strength (μSBS) to dentin after storage in distilled water at 37°C for 24h and 6 months. Five experimental adhesives were prepared with: CQ, DABE, BHT, ethanol, HEMA, TEGDMA, Bis-EMA, UDMA, and Bis-GMA. Concentrations of 0 wt%, 3 wt%, 9 wt%, 12 wt% or 15 wt% of MDP were added to their composition.
View Article and Find Full Text PDFJ Prosthodont Res
October 2020
Purpose: To evaluate the shear bond strength (SBS) between Y-TZP and a resin luting agent, after 1 of 2 enhancing strategies with TiO-nts was applied, either to the resin luting agent or the Y-TZP mass, in different concentrations.
Methods: In the Strategy TiO-nts on ceramic, the resin luting agent Panavia F2.0™ (Kuraray) and an experimental Y-TZP with added concentrations of TiO-nts (0%, 1%, 2%, and 5% vol/vol) and a commercial Y-TZP, comprised 5 different groups (n = 10).
This study aimed to evaluate the polymerization properties of bulk-fill materials (low and high-viscosity) by using high-intensity continuous light and intermittent photo-activation in terms of polymerization shrinkage stress and degree of conversion (DC). The following Bulk-fill and Conventional nanofilled resin composites were evaluated: Filtek Z350XT Flow (3M/ESPE), SureFil SDR Flow (Dentsply), Filtek Bulk Fill Flow (3M/ESPE), Filtek Z350XT (3M/ESPE) and Filtek Bulk Fill Posterior (3M/ESPE). A LED device (DB 685, Dabi Atlante) was used for both protocols: continuous uniform and intermittent photo-activation (light-on and light-off cycles) with identical radiant exposure (14 J/cm2).
View Article and Find Full Text PDFObjective: Extensive restorations in posterior teeth always bring doubts to the clinicians regarding the best protocol, mainly when structures of reinforcement were lost.
Objective: This study aimed to evaluate the effect of beveling on the fracture resistance and pattern of class II (MOD) restored teeth.
Methodology: Ninety human premolars were randomly assigned into 9 groups: CTR (control/sound); NC (cavity preparation, non-restored); RU (restored, unbeveled); RTB (restored, entire angle beveling); RPB (restored, partial/occlusal beveling); EC (endodontic access/EA, non-restored); EU (EA, unbeveled); ETB (EA, entire angle beveling); EPB (EA, partial/occlusal beveling).
Objective: This study aims to evaluate the effect of sonochemical treatment on the surface of yttria-stabilized tetragonal zirconia (Y-TZP) before and after the final sintering.
Material And Methods: Twenty-eight Y-TZP discs were divided into four groups (n=7), according to surface treatment: PRE: pre-sintering sonication with 30% nominal power for 15 min; POS: post-sintering sonication with 30% nominal power for 15 min; JAT: air abrasion with 50-μm alumina particles; and CON: control group with no treatment. The POS and JAT groups were sintered before sonication and the PRE group after sonication.
We assessed the effect of a new coating material based on resin-modified glass-ionomer with calcium (Ca) in inhibiting the demineralization of underlying and adjacent areas surrounding caries-like lesions in enamel. The measures used were surface hardness (SH) and cross-sectional hardness (CSH). Thirty-six bovine enamel specimens (3 × 6 × 2 mm) were randomly allocated into three groups (n = 12): No treatment (NT); resin-modified glass-ionomer with Ca (Clinpro XT Varnish, 3M ESPE) (CL), and fluoride varnish (Duraphat, Colgate) (DU).
View Article and Find Full Text PDFZirconia-reinforced lithium silicate (ZLS) has recently been introduced in an effort to improve the mechanical properties of glass-ceramic materials. In vitro evaluations suggest that this class of material has high flexural strength and exhibits satisfactory adhesion to resin cement and wear resistance. Since few clinical reports of this novel material are currently available, the aim of this case report is to describe clinical perceptions regarding the handling and performance of ZLS ceramics when used for laminate veneers on the maxillary incisors.
View Article and Find Full Text PDFUnlabelled: Bulk-fill composites were introduced in dentistry to accelerate clinical procedures while providing adequate outcomes. Concerns regarding the use of bigger composite increments rely on the polymerization shrinkage and shrinkage stress, which may generate gaps on the adhesive interface and result in a reduced success rate.
Objective: To evaluate the polymerization shrinkage stress of different bulk-fill resin composites and their elastic modulus.
Objective: This study aims to evaluate the influence of the light activation of simplified adhesives on the shear bond strength of resin cements to a glass-ceramic. Three factors were evaluated: (1) cement in two levels (light cured and dual cured); (2) adhesive in two levels (Single Bond 2 and Single Bond Universal), and (3) light activation in two levels (yes or no).
Materials And Methods: Thirty-two 1-mm thick slices of a leucite-reinforced glass-ceramic (IPS Empress CAD) were divided into eight groups according to adhesive (Single Bond 2 or Single Bond Universal), cement (AllCem Veneer or AllCem), and light activation of the adhesive before application of the cement (yes or no).
Statement Of Problem: Despite numerous advantages such as high strength, the bond of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) to tooth structure requires improvement.
Purpose: The purpose of this in vitro study was to evaluate the incorporation of TiO nanotubes into zirconia surfaces and the bond strength of resin cement to the modified ceramic.
Material And Methods: TiO nanotubes were produced by alkaline synthesis, mixed with isopropyl alcohol (50 wt%) and applied on presintered zirconia disks.
Objectives.: Sandblasting is a common method to try to improve the Y-TZP/veneer bond strength of dental prostheses, however, it may put stress on zirconia surfaces and could accelerate the t→m phase transformation. Y-TZP sandblasting before sintering could be an alternative to improve surface roughness and bonding strength of veneering ceramic.
View Article and Find Full Text PDFDue to improvements in esthetic dentistry, the number of patients seeking to obtain a more harmonious smile has increased. A 40-year-old woman was referred for treatment because she was dissatisfied with the effect that diastemas and a conoid tooth had on her smile. Her maxillary anterior teeth were relatively short, resulting in a compromised esthetic relationship between height and width.
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