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1.
J Adv Prosthodont ; 12(5): 273-282, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33149848

RESUMEN

PURPOSE: To assess shear bond strengths (SBS) of resin composites on aged and non-aged prosthetic materials with various surface treatments. MATERIALS AND METHODS: Cerasmart (CE), Vita Enamic (VE), Vita Mark II (VM), and IPS e.max CAD (EC) blocks were sliced, and rectangular-shaped specimens (14 × 12 × 1.5 mm; N = 352) were obtained. Half of the specimens were aged (5000 thermal cycles) for each material. Non-aged and aged specimens were divided into 4 groups according to the surface treatments (control, air abrasion, etching, and laser irradiation; n = 11) and processed for scanning electron microscopy (SEM). The repair procedure was performed after the surface treatments. SBS values and failure types were determined. Obtained data were statistically analyzed (P≤.05). RESULTS: The material type, surface treatment type, and their interactions were found significant with regard to SBS (P<.001). Aging also had a significant effect on prosthetic material-resin composite bonding (P<.001). SBS values of non-aged specimens ranged from 12.16 to 17.91 MPa, while SBS values of aged specimens ranged from 9.46 to 15.61 MPa. Non-aged VM in combination with acid etching presented the highest score while the control group of aged CE showed the lowest. CONCLUSION: Etching was more effective in achieving durable SBS for VM and EC. Laser irradiation could be considered as an alternative surface treatment method to air abrasion for all tested materials. Aging had significant effect on SBS values generated between tested materials and resin composite.

2.
Int J Prosthodont ; 33(5): 536-545, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32956435

RESUMEN

PURPOSE: To evaluate the shear bond strength (SBS) and color stability (ΔE) of four ceramic veneers (VITA VM 9; VITA VM 13; VITA VMK 95; and IPS e.max Ceram) following repair with three different self-adhesive composite resins (Fusio Liquid Dentin; Constic; and Vertise Flow) and BISCO Intraoral Repair Kit + Filtek Supreme (BC + FS). MATERIALS AND METHODS: A total of 96 specimens were prepared per ceramic material, and each ceramic group was divided into subgroups according to testing method (32 specimens for color stability analysis and 64 specimens for SBS testing). ΔE and SBS (SBS1 = non-aged, SBS2 = thermally aged) values of the repaired specimens were calculated. One specimen from each of the thermally aged groups was investigated under scanning electron microscopy (SEM). Two-way ANOVA was used to analyze the mean ΔE, SBS1, and SBS2 values. The differences between SBS1 and SBS2 values were analyzed using independent-samples t test. RESULTS: The lowest ΔE values were calculated for Constic (P ≤ .05). The SBS2 values among all groups were lower than the SBS1 values (P ≤ .05). The lowest SBS2 values were observed for Vertise Flow (2.3 ± 1.47 MPa) (P ≤ .05) and were below the acceptable limit of 5 MPa. CONCLUSION: All of the investigated repair materials in combination with the ceramic veneers exhibited ΔE values that were higher than the clinically acceptable limits. Thermal aging negatively affected the SBS values in all groups (P ≤ .05). All tested self-adhesive composite resins, with the exception of Vertise Flow, could be used instead of a repair kit with flowable composite resin, especially in noncooperative patients, for the purpose of repairing chipping fractures for VITA VM 9, VITA VM 13, and VITA VMK 95 (P > .05).


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Resinas Acrílicas , Cerámica , Color , Resinas Compuestas , Porcelana Dental , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
3.
J Esthet Restor Dent ; 32(6): 607-614, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32445503

RESUMEN

OBJECTIVE: The objective of the present research was to evaluate the effect of sintering temperatures (1350°C, 1450°C, and 1600°C) of a novel multi-layered esthetic zirconia material (Katana 12Z/STML) on the grain sizes and on the translucency parameters (TP00 ) for 2 different shades (A2-A3) and 2 different thicknesses (1-1.5 mm). MATERIAL AND METHODS: A total of 120 non-sintered specimens were randomly divided into three subgroups according to sintering temperatures. The TP00 and grain sizes of the sintered specimens were calculated. Statistical analyses were performed using 3-way ANOVA, 1-way ANOVA, and Tukey's post hoc tests. RESULTS: TP00 increased 1.2 to 1.5 times as the specimen thickness decreased from 1.5 to 1 mm (P ≤ .05). The lowest TP00 values were recorded for sintering at 1350°C for the investigated thicknesses and shades (P ≤ .05). The interaction of sintering temperature and shade was significant (P ≤ .05). Grain sizes were ordered according to sintering temperature as 1350°C < 1450°C < 1600°C (P ≤ .05). CONCLUSIONS: TP00 values decreased with the increase in the thickness of the monolithic zirconia. The sintering temperatures and their interaction with shade significantly affected TP00 values. The grain size increased with increasing sintering temperature. CLINICAL SIGNIFICANCE: The translucency of a novel multi-layered monolithic zirconia increased with higher sintering temperatures and lower thickness. The grain size increased with the increase in the sintering temperature. The sintering temperature of 1600°C led to a significant change in translucency for shade A3.


Asunto(s)
Cerámica , Materiales Dentales , Ensayo de Materiales , Propiedades de Superficie , Temperatura , Circonio
4.
J Esthet Restor Dent ; 31(2): 147-152, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30786134

RESUMEN

OBJECTIVES: To evaluate the relative translucency parameter (RTP) values of computer-aided design (CAD)-computer-aided manufacturing (CAM) materials after UV aging. MATERIALS AND METHODS: 70 specimens (n = 10) of Bruxzir Anterior (BA); E.max Cad (EC); Lava Ultimate (LU); Cerasmart (CE); Vita Enamic (VE); Vita Suprinity (VS); Vita Mark II (VM) were prepared (1 mm ± 0.01 mm). Color measurements were performed using a spectrofotometer (VITA Easyshade). RTP values of the specimens before (RTP1 ) and after UV aging (RTP2 ) were evaluated. Statistical analyses were done with repeated measurements of two-way-ANOVA with Bonferroni test (P < 0.05). RESULTS: Evaluating RTP1 and RTP2 values; significant differences were found (P < 0.05). There were no significant difference between the RTP1 values of CE and VS (P = 0.779); EC and VM (P = 0.952); VM and LU (P = 0.995); EP and LU (P = 0.653). Evaluating RTP2 values; VE and BA were found significantly different from the others (P < 0.05). For all evaluated groups TP values decreased after UV aging (P < 0.05). The most RTP reduction was observed for LU; while VM and EC were less affected. CONCLUSION: Glass ceramic VE showed the highest RTP and zirconia-based BA was the most opaque restorative CAD-CAM material. UV aging caused the CAD-CAM materials get more opaque. CLINICAL SIGNIFICANCE: In cases where translucency is needed chosing VE would give better esthetic results; while zirconia-based BA should be used if more opaque restoration is needed. Clinicians should be aware of that restorations get more opaque after usage.


Asunto(s)
Cerámica , Estética Dental , Diseño Asistido por Computadora , Materiales Dentales , Porcelana Dental , Ensayo de Materiales , Propiedades de Superficie
5.
Niger J Clin Pract ; 21(7): 925-931, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29984727

RESUMEN

Objectives: To investigate the color relationships between the anterior teeth in vivo. Materials and Methods: A total of 640 volunteers (age: 18-22) participated in the study. The color measurements of left maxillary and mandibular central, lateral, and canine were performed using a colorimeter. Color differences were calculated according to the CIE L*a*b* (ΔE*) and CIEDE2000 (ΔE00*) system. The National Bureau of Standards (NBS) ratings were also evaluated. Statistical analyses were performed using two-way ANOVA and Fisher's exact test (P < 0.05). Results: Significant differences were found between the L*, a*, b*, and ΔE* values (P < 0.05), except for mandibular central and lateral. ΔE* values were found between 1.5 ΔE* (mandibular central-mandibular lateral) and 8.1 ΔE* (maxillary central-maxillary canine). While the highest L* (80.5) and the least b* (15.1) values were obtained for mandibular central, the mean L* (73.6) and the mean b* values (21.3) were obtained for the maxillary canine. a* value was found to be highest for the mandibular lateral (1.1) and the least for the maxillary central (-0.2) teeth. NBS values were between 1.3 and 7.4 units, and only mandibular central and mandibular lateral teeth exhibited "almost the same" color values, while the other teeth exhibited "slightly different," "very different," or "remarkably different" color values. Conclusion: Anterior maxillary and mandibular teeth exhibited "different" color values. Only mandibular incisors and mandibular laterals showed "almost the same" color. Canines were more dark/red/yellow for both mandible and maxilla. Centrals were more bright/green/yellow for maxilla and bright/green/blue for mandibular. Clinicians should select the color one by one for each tooth and be aware of their color relations for optimal esthetics.


Asunto(s)
Color , Diente Canino , Estética Dental , Incisivo , Adolescente , Análisis de Varianza , Femenino , Humanos , Masculino , Mandíbula , Maxilar , Adulto Joven
6.
J Prosthet Dent ; 120(1): 107-113, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29310878

RESUMEN

STATEMENT OF PROBLEM: Esthetic computer-aided design and computer-aided manufacturing (CAD-CAM) materials have various chemical compositions and can be prepared by using different finishing and polishing procedures. Their optical properties may change over time, depending on these factors. However, information about their stain resistance is still scarce. PURPOSE: The purpose of this in vitro study was to evaluate the optical properties of esthetic CAD-CAM materials after different finishing and polishing procedures and ultraviolet (UV) aging. MATERIAL AND METHODS: Lava Ultimate, Cerasmart, Vita Enamic, Vita Suprinity, and Vita Mark II materials were used. A total of 150 specimens (14×12×1 mm) were prepared (n=10). A spectrophotometer was used to measure color parameters after different finishing and polishing procedures (control, manual polishing, glazing) and ultraviolet (UV) aging. Lightness (L*), green-red (a*), blue-yellow (b*), chroma (Ch), and hue (h) parameters were recorded, and change in lightness (ΔE*) values were calculated. Statistical analyses were performed with 2-way ANOVA, the Fisher least significant difference test, and the paired samples t test (α=.05). RESULTS: Significant interactions were noted between the aging conditions, material type, and finishing and polishing procedures for all evaluated parameters (P<.001). Vita Suprinity and Vita Mark II glazing groups resulted in significantly higher L1* values (P<.05) after the first color measurements. The b1* and C1 values of Vita Suprinity were higher than for other materials (P<.05). The highest ΔE* value was observed in the Lava Ultimate-glazing group (ΔE*=22.7) and the lowest in the Vita Mark II-control group (ΔE*=0.86). CONCLUSIONS: The optical properties of CAD-CAM materials can be affected by the material type and the applied surface finishing and polishing procedure. Manual polishing seems to be a better choice for Lava Ultimate and Cerasmart and glazing for Vita Enamic. For ceramic materials, manual polishing or glazing can be recommended in terms of color stability.


Asunto(s)
Cerámica/química , Diseño Asistido por Computadora , Estética Dental , Color , Pulido Dental/métodos , Porcelana Dental/química , Diseño de Prótesis Dental , Técnicas In Vitro , Ensayo de Materiales , Espectrofotometría , Propiedades de Superficie , Rayos Ultravioleta
7.
Biomed Res Int ; 2018: 9673562, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30911538

RESUMEN

Objective: To evaluate the effect of different desensitizing toothpastes and coffee staining on the discoloration rate of natural human tooth and composite materials. Materials and Methods: A total of 56 human teeth and 56 composite specimens were used. After initial color measurements were taken, specimens and teeth were exposed to simulated toothbrushing with six desensitizing toothpastes containing different active ingredients: stannous fluoride, strontium acetate, potassium citrate and hydroxyapatite, cetylpyridinium chloride, arginine, and novamin. Specimens were then exposed to coffee staining. Throughout the staining procedure, the storing solution was refreshed every day and the specimens were brushed with the tested toothpastes. Color measurements and changes were recorded at each stage and analyzed with one-way ANOVA, Dunnett tests, and paired sample t-test (p<0.05). Results: The largest color change was obtained with the stannous fluoride toothpaste after coffee staining for natural teeth (2.6 ΔE 00 ⁎) and composite specimens (3.1 ΔE 00 ⁎). Coffee staining resulted in significant changes for ΔE 00 ⁎ values of all groups, except for natural teeth brushed with a novamin-based (p= 0.06) toothpaste. For composite specimens, only the stannous fluoride and cetylpyridinium chloride-based toothpastes resulted in significant color changes relative to the control group. ΔL⁎ and Δb⁎ values were also increased after staining for all groups (p<0.05). Conclusions: Desensitizing toothpastes alone did not cause perceptible color changes; however, in combination with coffee staining, it tended to increased discoloration for both composites and natural teeth.


Asunto(s)
Café , Pigmentación/efectos de los fármacos , Diente , Cepillado Dental , Pastas de Dientes/farmacología , Humanos
8.
J Clin Pediatr Dent ; 40(2): 113-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26950811

RESUMEN

OBJECTIVE: A fractured whole crown segment can be reattached to its remnant; crowns from extracted teeth may be used as pontics in splinting techniques. We aimed to evaluate the effect of different storage solutions on tooth segment optical properties after different durations. STUDY DESIGN: Sixty central incisor crowns were divided into 6 groups (n = 10); Group 1 was kept dry; Groups 2, 3, 4, 5, and 6 were placed in an isotonic solution, water, milk, saliva, and casein-phosphopeptide-amorphous-calcium-phosphate (CPP-ACP), respectively, for 30 min, 12 h, 1 day, 1 week, and 3 weeks. Color values were measured using a colorimeter. Data were analyzed with Kruskal-Wallis tests, Mann-Whitney U-tests, and Friedman Wilcoxon tests with Bonferroni stepwise corrections (p < 0.05). RESULTS: ΔE* values varied from 0.3 to 15.3 over the 3 week period. Group 1 demonstrated the greatest color changes over all durations; Group 6 exhibited the least. L*, a*, b*, and ΔE* values varied between time periods in all groups; the differences were significant (p < 0.01), except for L* and ΔE* values in Group 2 and a* values in Group 6 (p > 0.01). Comparing ΔE* values, Group 6 was significantly different from the other groups for all durations (p < 0.01), except Group 4. CONCLUSIONS: A CPP-ACP complex solution seems a good choice for tooth fragment storage. Milk and saliva solutions may cause perceptible color changes if tooth fragments are stored for 3 weeks before use.


Asunto(s)
Estética Dental , Incisivo/anatomía & histología , Soluciones Preservantes de Órganos/uso terapéutico , Corona del Diente/anatomía & histología , Animales , Caseínas/uso terapéutico , Color , Colorimetría/instrumentación , Desecación , Humanos , Soluciones Isotónicas/uso terapéutico , Leche/química , Saliva Artificial/uso terapéutico , Cloruro de Sodio/uso terapéutico , Factores de Tiempo , Agua/química
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