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1.
J Evid Based Dent Pract ; 20(1): 101413, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32381415

RESUMEN

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Antagonist enamel wear of tooth-supported monolithic zirconia posterior crowns in vivo: A systematic review. Gou M, Chen H, Kang J, Wang H. J Prosthet Dent 2019;121:598-603. SOURCE OF FUNDING: This study was funded by the authors. TYPE OF STUDY/DESIGN: Systematic review and meta-analysis.


Asunto(s)
Alisadura de la Restauración Dental , Desgaste de los Dientes , Coronas , Esmalte Dental , Humanos , Circonio
2.
Eur J Prosthodont Restor Dent ; 28(1): 28-35, 2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32057198

RESUMEN

The purpose of this study was to evaluate two-body wear and hardness of new generation artificial resin teeth. Ten specimens of four different artificial resin teeth (nanofill composite, nanohybrid composite, microfiller reinforced acrylic and highly modified acrylic) were prepared. Specimens were thermodynamically loaded in a dual-axis chewing simulator (50N, 240,000 cycles, 1.6 Hz, 5/55°C thermocycle). The wear loss was analyzed by using plaster replicas and 3D laser scanner. Vickers hardness was determined before and after thermodynamic loading. Mean Vickers hardness values of highly modified acrylic resin teeth were statistically significantly lower than nanohybrid composite (p⟨0.001), nanofilled composite (p⟨0.001) and microfiller reinforced acrylic resin teeth (p⟨0.001). Mean wear loss of highly modified and microfiller reinforced acrylic resin teeth were statistically significantly lower than nanohybrid composite (p⟨0.001) and nanofilled composite (p⟨0.001) resin teeth. There was a statistically significant difference in wear among the materials. The correlation between hardness and wear was not statistically significant.


Asunto(s)
Resinas Compuestas , Alisadura de la Restauración Dental , Porcelana Dental , Análisis del Estrés Dental , Dureza , Ensayo de Materiales , Propiedades de Superficie , Diente Artificial
3.
Oper Dent ; 45(3): E156-E166, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32053459

RESUMEN

The purpose of this laboratory study was to compare the two-body wear resistance of different restorative materials commonly used for the indirect restoration of posterior teeth. The tested materials, based on ceramic (Imagine Press X, IPS e.max CAD, Milled Celtra Duo, Glaze-Fired Celtra Duo, Vita Mark II) and composite (Enamel Plus HRi, Enamel Plus HRi Bio-Function, Filtek Supreme XTE, Lava Ultimate), were compared with the wear properties of a type III gold alloy (Aurocast 8). Flat samples were prepared with a 6-mm thickness (n=10). Composite samples were tested after a heat polymerization cycle. All samples were exposed to a two-body wear test in a dual axis chewing simulator performing over 120,000 loading cycles. The opposing abrader cusps were fabricated from yttria-stabilized tetragonal zirconia polycrystal. The vertical substance loss (mm) and the volume loss (mm3) were recorded, as was the wear of the antagonist cusp (mm). Mean values were analyzed by one-way analysis of variance. Significant differences among materials were detected. The heat-cured resin-based composite material Enamel Plus Bio-Function and the type III gold alloy demonstrated similar mean values for wear depth and volumetric loss.


Asunto(s)
Materiales Dentales , Porcelana Dental , Cerámica , Resinas Compuestas , Esmalte Dental , Alisadura de la Restauración Dental , Aleaciones de Oro , Ensayo de Materiales , Propiedades de Superficie
4.
J Adhes Dent ; 22(1): 59-64, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32030376

RESUMEN

PURPOSE: To investigate simulated localized and generalized wear of self-adhesive restorative materials. MATERIALS AND METHODS: Three commercially available restorative materials and one experimental material with self-adhesive properties were evaluated. The experimental material was tested in both light-cured and self-cured conditions. Activa (A), Fuji II LC (F), and Equia Forte (E) and the experimental material ASAR-MP4 (S) were investigated. Two kinds of wear were simulated in an Alabama wear machine. Localized wear was simulated with a stainless-steel ball bearing antagonist and generalized with a flat-ended stainless-steel cylinder antagonist. The wear challenge was carried out in an aqueous slurry of polymethyl methacrylate beads. Material volume loss was measured on polyvinyl siloxane replicates of each worn surface using a Proscan 2100 noncontact profilometer in conjunction with Proscan and AnSur 3D software. RESULTS: There were significant differences (p < 0.05) among the materials for both generalized and localized wear. The experimental material in both curing modes exhibited significantly less localized wear than F and A and significantly less generalized wear than F and E. CONCLUSION: Self-adhesive materials offer unique handling properties for direct placement of posterior restorations in permanent teeth. The experimental material ASAR-MP4 generated similar wear values to the other self-adhesive materials tested.


Asunto(s)
Resinas Compuestas , Alisadura de la Restauración Dental , Cementos Dentales , Materiales Dentales , Cementos de Ionómero Vitreo , Ensayo de Materiales , Propiedades de Superficie
5.
Dent Mater ; 36(3): 442-455, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32001023

RESUMEN

OBJECTIVES: The main goal of this work is to evaluate the suitability of nanostructured zirconia pieces obtained by robocasting additive manufacturing (AM), for dental applications. METHODS: The density, crystalline structure, morphology/porosity, surface roughness, hardness, toughness, wettability and biocompatibility of the produced samples were compared with those of samples obtained by conventional subtractive manufacturing (SM) of a similar commercial zirconia material. Chewing simulation studies were carried out against dental human cusps in artificial saliva. The wear of the material was quantified and the wear mechanisms investigated, as well as the influence of glaze coating. RESULTS: AM samples, that revealed to be biocompatible, are slightly less dense and more porous than SM samples, showing lower hardness, toughness and wettability than SM samples. After chewing tests, no wear was found both on AM and SM samples. However, the dental wear was significantly lower when AM samples were used as counterbody. Concerning the glazed samples, both coated surfaces and dental cusps suffered wear, being the cusps' wear higher than that found for unglazed samples. More, cusps tested against AM coated samples suffered less wear comparatively to those opposed to SM coated samples. SIGNIFICANCE: Overall, the results presented in this paper show that AM processed nanostructured zirconia can be used in dental restorations, with important advantages from the point of view of processing and tribological performance. Moreover, the option for glaze finishing should be carefully considered both in SM and AM processed specimens.


Asunto(s)
Porcelana Dental , Alisadura de la Restauración Dental , Pulido Dental , Humanos , Ensayo de Materiales , Impresión Tridimensional , Propiedades de Superficie , Circonio
6.
J Prosthet Dent ; 124(4): 488-493, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31952860

RESUMEN

STATEMENT OF PROBLEM: The use of dissimilar materials for opposing complete-mouth implant-supported prosthesis has become popular, especially when one arch is made from anatomical contour zirconia. However, the amount of wear zirconia causes on resin and other denture tooth materials is largely unknown. PURPOSE: The purpose of this in vitro study was to determine the volumetric wear of 4 commercially available resin materials used for denture teeth in complete-arch implant-supported prostheses opposed by zirconia. MATERIAL AND METHODS: A total of 32 maxillary central incisor denture teeth were evaluated (n=8): double crosslinked polymethyl methacrylate (PMMA) (DCL), nanohybrid composite resin (PHO), and computer-aided design and computer-aided manufacturing (CAD-CAM)-fabricated teeth made from crosslinked PMMA (TEL) and acrylate polymer (ZCAD). Antagonist cone-shaped specimens were milled from zirconia. Specimens were mounted in acrylic resin, polished to a flat surface by using 1200-grit SiC paper, and stored in water (37 °C for 24 hours) before exposure in a custom dual-axis wear simulator for 200 000 cycles with a vertical load of 20 N, a horizontal slide of 2 mm, and a frequency of 1 Hz. Volumetric wear was measured by using a noncontact profilometer and a superimposition software program. Data were analyzed with a 1-way analysis of variance (ANOVA) and the Tukey Honestly Significant Difference (HSD) post hoc test (α=.05). RESULTS: A statistically significant difference in volumetric wear was found between groups (P<.001), with PHO (4.3 ±1.0 mm3)

Asunto(s)
Alisadura de la Restauración Dental , Circonio , Resinas Compuestas , Ensayo de Materiales , Propiedades de Superficie
7.
J Prosthet Dent ; 124(3): 387-394, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31784192

RESUMEN

STATEMENT OF PROBLEM: Additive manufacturing technology can be used for denture bases and also denture teeth. Therefore, the mechanical properties of 3D-printed resin denture teeth should be evaluated. PURPOSE: The purpose of this in vitro study was to compare the wear resistance of 3D-printed denture tooth resin with that of conventionally prefabricated denture teeth. MATERIAL AND METHODS: Eighty substrate specimens were prepared with 5 kinds of resin denture teeth: 3D-printed denture tooth resin (DENTCA denture tooth resin; DENTCA, Inc), Artic 6 (Kulzer GmbH), Preference (Candulor AG), Premium 6 (Kulzer GmbH), and Surpass (GC Corp). The 3D-printed denture tooth specimens were made of methacrylate-based photopolymerized resin by stereolithography 3D printing. Antagonistic surfaces were made from zirconia by milling and from cobalt-chromium (Co-Cr) alloy by 3D printing and casting. The specimens were loaded at 49 N for 30 000 cycles under thermocycling conditions in a mastication simulator. Wear resistance was measured by calculating the volume of substance lost. Wear surface characteristics were observed by using a scanning electron microscope (SEM). Two-way ANOVA was used to analyze the data (α=.05). RESULTS: The influence of the resin denture teeth and the type of antagonist were both statistically significant. The wear volume loss of the 3D-printed denture tooth resin was higher than that of Artic 6 and Preference when opposing the zirconia and the metal antagonists (P<.05). The 3D-printed denture tooth resin did not show a significant difference from Premium 6 with the zirconia and the metal antagonists or Surpass with the zirconia antagonist. From the SEM images, the specimens of the 3D-printed denture tooth resin showed a relatively smooth surface with the zirconia antagonist and exhibited cracks when opposed by the metal antagonist. CONCLUSIONS: The results suggest that 3D-printing by using resin materials provides adequate wear resistance for denture tooth use.


Asunto(s)
Resinas Sintéticas , Desgaste de los Dientes , Quelantes , Alisadura de la Restauración Dental , Dentaduras , Ensayo de Materiales , Impresión Tridimensional , Propiedades de Superficie , Circonio
8.
Dent Mater J ; 39(1): 126-134, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31611495

RESUMEN

The purpose of the study was to test new method for in vitro evaluation of dental material wear with 3D digitization procedure. Thirty dental crowns, made of polyetheretherketone and veneered with composite material, were subjected to wear test. The crown surface was digitized using coordinate measuring machine before and after the performed wear test. Mesh 3D models were reconstructed and average and maximum depth of lost material and volume loss was calculated (GOM Inspect 2016 software). Mean average depth value amounted 12±7 µm, maximum depth value was 42 µm, while mean volume loss was 0.0024 mm3. The smallest measured values were 4 µm for depth value and 0.0003 mm3 for volume loss. Coefficient of variation was very high for all tested parameters (>50%) as a result of data inconsistency. Within the limitations of applied methodology, the possibility of using coordinate measuring machine in measurement of dental material wear was confirmed.


Asunto(s)
Desgaste de los Dientes , Diente , Coronas , Materiales Dentales , Alisadura de la Restauración Dental , Humanos , Ensayo de Materiales , Propiedades de Superficie , Corona del Diente
9.
Braz. dent. sci ; 23(4): 1-12, 2020. tab, ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1121307

RESUMEN

Objective: to evaluate the clinical performance of the dual shade layering and polychromatic resin composite layering techniques using a randomized controlled trail. Material and Methods: 42 participants (84 restorations) of class IV or class III through and through within a pair of anterior contra-lateral teeth were randomly allocated into two groups according to technique of composite restoration placement: control "polychromatic layering" and intervention "dual-shade layering". Follow-up was done at 1 month (baseline) and 1 year. Restorations were evaluated using Visual Analog Scale (VAS), restoration color shade match using Vita Easyshade V ®, and blinded assessor using FDI criteria for assessment of dental restorations measuring (aesthetic properties). Chi-square test was used to compare between restorations of both techniques. Results: There was no statistically significant difference between restorations of both techniques for patient satisfaction outcome, restorations color match outcome, and for all tested FDI outcomes except surface luster with 100% success. Conclusion: Bothdual-shade layering and polychromatic natural layering techniques, exhibited acceptable clinical and esthetic performance (AU)


Objetivo: Avaliar o comportamento de desgaste do esmalte humano e lascamento de zircônia de cobrimento e monolítica para restaurações posteriores de cobertura total. Material e métodos: Trinta e quatro restaurações de zircônia de cobertura total (dezessete em cada grupo) foram fabricadas. Os pacientes foram divididos em dois grupos de acordo com o tipo de zircônia utilizada; grupo 1 (grupo comparador) coroas com zircônia de cobrimento e grupo 2 (grupo de intervenção) coroas únicas de zircônia monolítica. Todas as coroas foram fabricadas e polidas em laboratório. Para medidas de desgaste de dentes opostos, foi utilizado um perfilômetro 3D sem contato, onde réplicas de resina epóxi foram construídas para o arco oposto imediatamente após a cimentação das coroas, três, seis e doze meses. O lascamento da restauração foi medido usando critérios modificados dos Serviços de Saúde Pública dos Estados Unidos (USPHS). Resultados: Todas as restaurações foram relatadas como alfa sem lascamento. Não houve diferença estatisticamente significativa entre (Grupo 1) e (Grupo 2) para o teste de desgaste. Conclusão: As restaurações monolíticas e de cobrimento revelaram propriedades mecânicas satisfatórias sem lascamento após um ano de uso clínico. O desgaste do esmalte oposto foi clinicamente aceitável para ambos os materiais (AU)


Asunto(s)
Humanos , Cerámica , Alisadura de la Restauración Dental , Desgaste de los Dientes
10.
São José dos Campos; s.n; 2020. 105 p. il., graf., tab..
Tesis en Portugués | BBO - Odontología | ID: biblio-1150839

RESUMEN

O presente estudo teve por objetivo avaliar o comportamento da camada de caracterização sobre zircônia de alta translucidez (YZHT, Vita YZ HT), cerâmica feldspática (FD/VMII, Vita Mark II) e silicato de lítio reforçado por zircônia (ZLS, Vita Suprinity) frente à simulação de desgaste fisiológico variando os antagonistas em YZHT, esteatita e cerâmica híbrida com polímero (Vita Enamic). Foram obtidos 120 discos (ø 12 mm, 1,2 mm de espessura) cerâmicos, sendo 30 de YZHT e FD, e 60 de ZLS, através de corte de blocos para CAD/CAM. As amostras de YZHT foram sinterizadas, e na sequência os grupos YZHT e FD receberam a camada de caracterização. A caracterização das amostras de ZLS foi realizada no mesmo ato da cristalização (ZLS1, etapa única) ou em queima posterior a cristalização (ZLS2, duas etapas). A caracterização foi realizada de acordo com as recomendações do fabricante e todas as amostras receberam aplicação de glaze e consequente queima. Os espécimes foram divididos em subgrupos (n=10) de acordo com os antagonistas: esteatita, cerâmica híbrida ou zircônia; em seguida, foram submetidos à simulação do desgaste fisiológico. Os parâmetros de rugosidade média (Ra) e largura média dos elementos do perfil de rugosidade (Rsm) foram analisados em diferentes momentos da simulação de desgaste fisiológico desde o início até o final da ciclagem. Após os 15.000 ciclos foram calculados a perda de massa dos discos cerâmicos e dos pistões antagonistas. Os resultados foram analisados estatisticamente por Anova 2 fatores e Tukey (p<0,05). Antes do desgaste, as cerâmicas não apresentaram diferenças para os parâmetros de rugosidade, Ra (p=0,3348), Rz (p=0,5590) e Rsm (p=0,5330). Os antagonistas não apresentaram diferenças para os parâmetros, Ra (p=0,0541) e Rsm (p=0,0613), enquanto que o parâmetro Rz (p=0,000) apresentou diferença, já que a esteatita (18,98 ± 2,98 µm) apresentou uma maior rugosidade média quando analisada a altura máxima do perfil quando comparado com os antagonistas em enamic (12,35 ± 0,91 µm) e zircônia (11,47 ± 0,89 µm). Após o desgaste, as cerâmicas continuaram sem apresentar diferenças estatísticas para os parâmetros de rugosidade, Ra (p=0,488), Rz (p=0,681) e Rsm (p=0,256). Os antagonistas não apresentaram diferença para o parâmetro Ra (p=0,124), porém, apresentaram diferença para o parâmetro Rz (p=0,000), já que a esteatita (57,98 ± 4,11 µm) apresentou uma maior média para tal parâmetro quando comparado com os antagonistas em enamic (44,86 ± 2,34 µm) e zircônia (37,81 ± 1,40 µm); e para o parâmetro Rsm (p=0,000), já que as médias da esteatita (502,72 ± 72,20 µm), enamic (385,67 ± 24,84 µm) e zircônia (268,94 ± 27,99 µm) apresentaram diferenças entre si. O tipo de cerâmica (p<0,0001) influenciou a perda de massa das amostras e a interação entre cerâmica e antagonista (p=0,0098), com isso influenciou a perda de massa dos pistões antagonistas. O grupo ZLS 2 apresentou a maior perda de massa entre os grupos testados. Todos os antagonistas testados apresentaram perda de massa semelhante contra o FD, enquanto a esteatita apresentou maior perda de massa quando testadas com amostras YHZT, ZLS 1 e ZLS 2. Todas as cerâmicas apresentaram rugosidade semelhante antes e após a simulação de desgaste. As amostras de cerâmicas apresentaram uma perda de massa semelhante. No entanto, a queima adicional da caracterização da cerâmica de silicato de lítio reforçado por zircônia favoreceu uma maior perda de massa, sem que houvesse alteração de sua resistência(AU)


The present study aimed to evaluate the behavior of the characterization layer on high translucency zirconia (YZHT, Vita YZ HT), feldspar ceramic (FD / VMII, Vita Mark II) and zirconia reinforced lithium silicate (ZLS, Vita Suprinity) compared to the simulation of physiological wear, varying the antagonists in YZHT, steatite and hybrid ceramic with polymer (Vita Enamic). 120 ceramic discs (ø 12 mm, 1.2 mm thick) were obtained, 30 from YZHT and FD, and 60 from ZLS, by cutting blocks for CAD / CAM. The YZHT samples were sintered, and in the sequence the groups YZHT and FD received the characterization layer. The characterization of the ZLS samples was carried out in the same act of crystallization (ZLS1, single step) or in burning after crystallization (ZLS2, two steps). The characterization was carried out according to the manufacturer's recommendations and all samples received application of glaze and consequent burning. The specimens were divided into subgroups (n = 10) according to the antagonists: steatite, hybrid ceramic or zirconia; then, they were submitted to the simulation of physiological wear. The parameters of average roughness (Ra) and average width of the elements of the roughness profile (Rsm) were analyzed at different moments of the simulation of physiological wear from the beginning to the end of the cycle. After 15,000 cycles, the mass loss of the ceramic discs and antagonistic pistons was calculated. The results were analyzed statistically by Anova 2 factors and Tukey (p <0.05). Before wear, the ceramics showed no differences for the roughness parameters, Ra (p = 0.3348), Rz (p = 0.5590) and Rsm (p = 0.5330). The antagonists showed no differences for the parameters, Ra (p = 0.0541) and Rsm (p = 0.0613), while the parameter Rz (p = 0.000) showed a difference, since steatite (18.98 ± 2) , 98 µm) presented a higher average roughness when the maximum profile height was analyzed when compared with the antagonists in enamic (12.35 ± 0.91 µm) and zirconia (11.47 ± 0.89 µm). After wear, the ceramics continued to show no statistical differences for the roughness parameters, Ra (p = 0.488), Rz (p = 0.681) and Rsm (p = 0.256). The antagonists showed no difference for the Ra parameter (p = 0.124), however, they showed a difference for the Rz parameter (p = 0.000), since steatite (57.98 ± 4.11 µm) showed a higher average for such parameter when compared with antagonists in enamic (44.86 ± 2.34 µm) and zirconia (37.81 ± 1.40 µm); and for the parameter Rsm (p = 0.000), since the averages of steatite (502.72 ± 72.20 µm), enamic (385.67 ± 24.84 µm) and zirconia (268.94 ± 27.99 µm ) showed differences between them. The type of ceramic (p <0.0001) influenced the loss of mass of the samples and the interaction between ceramic and antagonist (p = 0.0098), thereby influencing the loss of mass of the antagonist pistons. The ZLS 2 group showed the greatest loss of mass among the tested groups. All tested antagonists showed similar mass loss against FD, while steatite showed greater mass loss when tested with YHZT, ZLS 1 and ZLS 2 samples. All ceramics showed similar roughness before and after wear simulation. The ceramic samples showed a similar mass loss. However, the additional burning of the characterization of the zirconia-reinforced lithium silicate ceramic favored a greater loss of mass, without altering its strength(AU)


Asunto(s)
Cerámica/análisis , Alisadura de la Restauración Dental/efectos adversos , Materiales Dentales/síntesis química
11.
J Dent ; 90: 103210, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31600535

RESUMEN

OBJECTIVES: The present study examined the effects of Na+→K+ ion-exchange on the wear performance of feldspathic veneering porcelain. METHODS: Bar and disk specimens were prepared using IPS classic as the feldspathic veneering porcelain. After ion-exchange by immersion of the specimens in melted KNO3 at two temperatures for different time-periods, the bars were tested for flexural strength and Vickers surface hardness. The disks were paired with zirconia antagonists and tested with a pin-on-disk tribometer with 10 N for 70☓104 wear cycles in artificial saliva. Wear analysis of the porcelain and zirconia was performed using 3D profilometer and analysed with one-way analysis of variance and Tukey's post-hoc pairwise comparison procedures. Worn surfaces were examined with scanning electron microscopy. RESULTS: The feldspathic veneering porcelain exhibited strong time-dependent wear behaviour, with typical running-in and steady wear stages. Ion-exchange treatments at 380 °C and 440 °C both enhanced the mechanical properties, decreased the wear rates of running-in wear and steady wear. The wear performance of porcelain treated by ion-exchange at lower temperature (380 °C) was improved significantly, especially reducing the wear rate of the running-in stage. CONCLUSION: A thicker ion-exchange layer with less stress relaxation may be obtained by ion-exchange at lower exchange temperature for a long processing time. Such a protocol improves the wear performance of the porcelain effectively. CLINICAL SIGNIFICANCE: Restorations with veneering porcelain may fail prematurely due to excessive wear. It important to improve the wear performance of the porcelain. Ion-exchange has the potential to strengthen dental veneering porcelain. Understanding the effect of ion-exchange on the wear performance of porcelain provides insight improving the wear performance of these restorations.


Asunto(s)
Porcelana Dental/química , Coronas con Frente Estético , Circonio/química , Alisadura de la Restauración Dental , Análisis del Estrés Dental , Dureza , Humanos , Ensayo de Materiales , Propiedades de Superficie
12.
Biomed Mater Eng ; 30(4): 365-374, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31476141

RESUMEN

BACKGROUND: Ceramic crown that fires the layering porcelain on zirconia corping is starting to be used due to aesthetic requirements. However, many ceramics are used, but wear characteristics are often unknown. OBJECTIVE: This study was performed to investigate the wear of human enamel by porcelains, and to determine the influence of porcelain hardness, surface roughness and crystal of porcelain on the enamel wear. METHODS: Enamel specimens were prepared from extracted human molar teeth. Porcelain specimens were prepared from Deguceram Gold, Vita Omega 900, and Cercon Ceram Kiss. Enamel wear volume was calculated and the porcelain wear depth, surface roughness and Vickers hardness was measured. Moreover, the observation of a crystal by scanning electron microscope and the crystal by X-ray diffraction were identified. RESULTS: Omega 900 showed the smallest enamel wear volume and porcelain wear depth. The Vickers hardnesses of Omega 900 and Cercon Ceram Kiss were almost identical. Leucite was detected from Deguceram Gold and Omega 900, and Silica and Silicon Nitride were detected from Cercon Ceram Kiss. CONCLUSIONS: The enamel wear is influenced not by the hardness of the porcelain but by the surface roughness, the size and shape of the crystal.


Asunto(s)
Coronas , Esmalte Dental/anatomía & histología , Porcelana Dental/química , Coronas/efectos adversos , Cristalización , Esmalte Dental/química , Porcelana Dental/efectos adversos , Alisadura de la Restauración Dental/efectos adversos , Dureza , Humanos , Ensayo de Materiales , Propiedades de Superficie , Difracción de Rayos X
13.
J Mech Behav Biomed Mater ; 100: 103403, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31525551

RESUMEN

It is important to predict the wear behavior of a material as well as its potential to wear antagonized restorative materials. Thus, this study investigated the performance of zirconia-reinforced lithium silicate (ZLS) after wear with different antagonists. Thirty discs of ZLS were made and divided into three groups according to the antagonist (n = 10). Ten cylinders of each antagonist were also made. The parameters for the simulation of wear were: 30N, horizontal movement of 6 mm, and 1.7 Hz, totaling 300,000 cycles, in distilled water. Wear measurements (volume losses (mm3)) on the ZLS and antagonists were performed by digital optical profilometry or an analytical balance. Hardness of all materials was also measured, whereas roughness and Scanning Electron Microscopy (SEM) were only accessed for the ZLS. The wear and hardness values were subjected to one-way ANOVA and the Tukey Test (95%), while the roughness data was analyzed with paired T-test (95%). The hardness means of all materials were statistically different (zirconia > steatite = ZLS > acrylic resin) (p = 0.0001). Zirconia and steatite severely worn ZLS and only acrylic resin worn surfaces could be measured for roughness, which was significantly higher after wear (p = 0.007). SEM showed the ZLS's wear tracks when worn by steatite and zirconia. It was possible to observe differences of ZLS wear patterns depending on the antagonist and quantify the volumes worn with steatite (17.61 ±â€¯2.65) and zirconia (41.98 ±â€¯19.45), which were significantly different (p = 0.001). Acrylic resin promoted a superficial wear on ZLS that could not be quantified. In terms of the antagonists' materials, zirconia presented significantly different less volume loss compared to acrylic resin and steatite (p = 0.000). It can be concluded that zirconia caused more wear on ZLS than steatite and acrylic resin.


Asunto(s)
Cerámica/química , Alisadura de la Restauración Dental , Litio/química , Óxido de Magnesio/química , Resinas Sintéticas/química , Silicatos/química , Dióxido de Silicio/química , Circonio/química , Porcelana Dental , Análisis del Estrés Dental , Dureza , Técnicas In Vitro , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie
14.
J Appl Oral Sci ; 27: e20180297, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31166548

RESUMEN

INTRODUCTION: Polymer-based composite materials have been proposed as an alternative for single unit restorations, due to their resilient and shock absorbing behavior, in contrast to the brittleness of ceramic materials that could result in failure by fracture. OBJECTIVE: To evaluate the fatigue strength and damage modes of monolithic posterior resin nanoceramic and lithium disilicate glass ceramic crowns. METHODOLOGY: Twenty-six resin nanoceramic (RNC) and lithium disilicate glass ceramic (LD) 2 mm monolithic crowns (n=13) were cemented on composite resin replicas of a prepared tooth and subjected to cyclic load with lithium disilicate indenters for 2 million cycles. Specimens and indenters were inspected every 500,000 cycles and suspended when presenting fractures or debonding. Surviving specimens were embedded in epoxy resin, polished and subsurface damage was analyzed. Specimens presenting fractures or severe subsurface damage were considered as failures. Survival data was subjected to Fisher's exact test; damage modes were subjected to Mann-Whitney test (p<0.05). RESULTS: There were no debonding, cohesive or catastrophic failures. Considering subsurface damage, 53.8% of RNC and 46.2% of LD crowns survived the fatigue test, presenting no statistical difference. Chief damage modes were radial cracks for RNC and inner cone cracks for LD, presenting no statistical difference. CONCLUSIONS: The results suggest that if debonding issues can be resolved, resin nanoceramic figures can be an alternative to posterior crowns. Although distinct, damage modes revealed potential to cause bulk fracture in both glass ceramic and resin nanoceramic crowns.


Asunto(s)
Cerámica/química , Coronas , Porcelana Dental/química , Cementos de Resina/química , Diseño Asistido por Computadora , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Alisadura de la Restauración Dental , Restauración Dental Permanente/métodos , Análisis del Estrés Dental , Humanos , Ensayo de Materiales , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Propiedades de Superficie , Factores de Tiempo
15.
Niger J Clin Pract ; 22(3): 313-319, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30837417

RESUMEN

Background: Although there are several studies on permanent tooth wear caused by dental materials, studies concerning primary teeth are limited. Aim: To evaluate the wear of primary tooth enamel against different ceramic and composite resin materials. Settings and Design: In vitro study. Materials and Methods: We assessed five materials (n = 10 per group): monolithic zirconia (group Z), lithium disilicate glass ceramic (group L), resin nanoceramic (group R), nanohybrid composite resin (group C), and primary tooth enamel (group E). The mesiopalatal cusps of primary maxillary second molars were used as antagonists. Wear tests were performed in a dual-axis chewing simulator, and the volume loss in the antagonist tooth was evaluated using a laser scanner and three-dimensional profiling system. Statistical Analysis Used: Data were statistically analyzed using one-way analysis of variance with Tukey's post hoc tests (P < 0.05). Results: The maximum antagonist tooth wear was observed in group L (3.84 ± 0.7 mm3), followed by groups C (3.68 ± 0.76 mm3), R (3.48 ± 0.71 mm3), Z (2.66 ± 0.65 mm3), and E (1.66 ± 0.42 mm3). Volume loss was significantly lesser in group Z than in groups L and C (P < 0.05), whereas there were no significant differences among groups L, C, and R. Conclusion: Within the limitations of this in vitro study, our findings suggest that zirconia should be used for full coronal coverage in primary tooth restorations because it causes lesser antagonist tooth wear than does lithium disilicate, resin nanoceramic, and nanohybrid composite resin.


Asunto(s)
Cerámica/farmacología , Resinas Compuestas/química , Resinas Compuestas/farmacología , Esmalte Dental/patología , Materiales Dentales/química , Desgaste de los Dientes/etiología , Diente Primario/efectos de los fármacos , Porcelana Dental , Alisadura de la Restauración Dental , Análisis del Estrés Dental , Humanos , Masticación , Ensayo de Materiales , Propiedades de Superficie , Desgaste de los Dientes/diagnóstico , Desgaste de los Dientes/patología , Circonio
16.
Dent Mater J ; 38(3): 343-353, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30918233

RESUMEN

This review focusses on tribological aspects of teeth during function, the clinical significance of wear, wear of natural teeth and restorative materials and laboratory methods to simulate wear of restorative materials. Ceramic, metal alloy and amalgam show low material wear, whereas resin-based materials demonstrate substantial wear in the long term. The clinical wear shows a high variability with the patient factor accounts for about 50% of the variability. Wear as such seldomly compromises the function of the stomatognath system or individual teeth and is in most cases an esthetic problem. Particles that are ingested due to attrition and abrasion wear may pose a health risk to the patient, especially those from composite resin materials. However, systematic clinical studies on that issue are not available. For laboratory research many wear simulation devices and methods have been developed but only few are validated and have a moderate correlation with clinical wear.


Asunto(s)
Alisadura de la Restauración Dental , Estética Dental , Resinas Compuestas , Materiales Dentales , Porcelana Dental , Humanos , Ensayo de Materiales , Propiedades de Superficie
17.
J Dent ; 83: 87-94, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30849446

RESUMEN

OBJECTIVES: The present study examined the effect of food medium on the three-body wear behaviour of veneering porcelain derived from porcelain-fused-to-metal crowns. METHODS: Seventy-four rectangular metal-ceramic specimens were prepared using Ceramco III as the veneering porcelain. After storage in distilled water at 37 °C for 2 days, the specimens were tested with a custom-designed chewing machine with a stainless steel ball as antagonist (350 N loads, 2.4 × 106 cycles). Testing was performed using water, silica beads, poly(methyl) methacrylate beads, millet seed slurry, chicken slurry or celery slurry as abrasive medium. Wear analysis of the veneering porcelain was performed using a 3D profilometer after every 300,000 wear cycles and analysed with one-way analysis of variance and post-hoc pairwise comparison procedures. Worn surfaces were examined with scanning electron microscopy. RESULTS: The wear curves of all experimental groups demonstrated three wear stages (running-in, steady wear and severe wear) with characteristic microstructure of worn surfaces. All the three food items selected in the present study (celery, chicken and millet seeds) had lower hardness compared with the veneering porcelain and produced less abrasion of the porcelain than a two-body wear system (water only). Abrasive wear produced with silica particles was the highest for the veneering porcelain. CONCLUSION: The wear process of veneering porcelain in porcelain-fused-to-metal restorations is affected by the type of food consumed during mastication. CLINICAL SIGNIFICANCE: Excessive abrasion may lead to premature failure of porcelain-fused-to-metal restorations. The importance of the wear behaviour of dental ceramic materials cannot be overstated. Three-body wear is an unavoidable consequence of oral function and occurs daily during eating. Understanding the effect of food particles on the wear behaviour of dental porcelain provides insight into the clinical performance and durability of these restorations.


Asunto(s)
Porcelana Dental , Coronas con Frente Estético , Dieta/estadística & datos numéricos , Abrasión de los Dientes , Cerámica , Alisadura de la Restauración Dental , Masticación , Ensayo de Materiales , Propiedades de Superficie , Circonio
18.
J Dent Res ; 98(4): 437-442, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30744472

RESUMEN

Monolithic zirconia crowns have become very popular; their surface finish is considered a key factor for restoration longevity. While polishing has shown excellent results in vivo, the surface glass infiltration of zirconia may offer superior damage resistance and aesthetic advantages by using tooth-colored glasses. Thus, the purpose of this study is to evaluate the efficacy of polishing and glass infiltration on the wear behavior of monolithic zirconia crowns. The wear behavior of intact natural molar teeth was investigated as a reference. Zirconia crowns were divided into 3 groups: PolZ-sintered then polished; PolGZ-polished in the presintered state and then glass infiltrated and sintered; NoPolGZ-as machined, glass infiltrated and sintered. Crowns were adhesively bonded to a dentin-like abutment. Zirconia crowns and molar teeth ( n = 15) were subjected to contact-slide-liftoff cyclic loading (200 N, 1.25 million cycles) with a steatite sphere ( r = 3 mm) as an antagonist in water. Surface and subsurface damages were investigated with optical and scanning electron microscopies. Wear depth and volume loss were determined with micro-computed tomography. PolGZ and NoPolGZ crowns exhibited shallow wear scars, where material loss remained within the glass/zirconia layer with no visible cracks. Meanwhile, PolZ crowns presented no visible wear damage. Volume loss (mm3) in the steatite antagonist was as follows (mean ± SD): PolZ = 0.022 ± 0.007, PolGZ = 0.011 ± 0.004, and NoPolGZ = 0.014 ± 0.006. Molar teeth yielded no measurable wear on the antagonist, while the wear scar on the teeth was greater than that on zirconia crowns, ranging from 0.07 to 0.35 mm3. The combination of polishing and glass infiltration on the occlusal surface of monolithic zirconia crowns yielded reduced wear on both crown and antagonist.


Asunto(s)
Porcelana Dental , Alisadura de la Restauración Dental , Coronas , Esmalte Dental , Estética Dental , Ensayo de Materiales , Propiedades de Superficie , Microtomografía por Rayos X , Circonio
19.
J Mech Behav Biomed Mater ; 91: 287-293, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30611925

RESUMEN

This study evaluated the effect of two antagonist substrates (Y-TZP/zirconia or stainless steel) on the wear rate and surface alterations of different composite materials and bovine tooth substrates (enamel and dentin). The wear rate of different composite materials (n = 20; two direct composite resins: HelioMolar - HM; Clearfil AP-X - CAP, three indirect composite resins: Estenia C&B - EST; Adoro - ADO; Sinfony - SFY, and one composite resin for direct/indirect restorations: Filtek Z250 - Z250), bovine enamel and dentin against two different antagonist materials (zirconia or stainless steel) into two mediums (two-body and three-body wear) were collected. After wear tests on ACTA wear machine, Scanning Electron Microscopy (SEM) analysis was performed to access the surface alterations. The wear data were evaluated by three-way ANOVA and Tukey post-hoc test (α = 0.05). The factors 'antagonist', 'medium', 'restorative materials', and the interaction of all factors grouped by two and integrated showed statistical significance on the wear rates. A two-body test depicted no difference among all composites and enamel for wear rate, while a three-body test depicted differences among composites directly related to the filler content: EST < Z250 = CAP < ADO = HM < SFY. Dentin always showed the highest wear rates and enamel the lowest rates. The presence of food bolus (three-body test) led to higher wear rates in comparison to an only aqueous medium (two-body test). SEM analysis showed that different materials present specific wear patterns, regardless of the medium and the antagonist considered. Differently from enamel, dentin substrate was intensively prone to wear, regardless of the antagonist/medium. Resin composite substrates presented intermediate wear rates, depending directly on their filler content (% in weight).


Asunto(s)
Resinas Compuestas/química , Esmalte Dental/efectos de los fármacos , Alisadura de la Restauración Dental , Dentina/efectos de los fármacos , Acero Inoxidable/farmacología , Circonio/farmacología , Animales , Bovinos , Propiedades de Superficie
20.
Eur J Oral Sci ; 127(2): 156-161, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30609131

RESUMEN

Little is known about the wear rate of enamel and dentin opposing resin composite following restoration of the occlusal surface in patients with tooth wear. Hence, the aim of this in vitro study was to evaluate the wear of enamel and dentin surfaces when opposing each of three resin composites in a two-body and three-body wear test. The two-body and three-body wear of dentin, enamel, and three resin composites (Clearfil AP-X, Filtek Z250, and Filtek Supreme) opposing four antagonists (stainless steel and three resin composites) were evaluated using the ACTA wear machine. In addition, all the surfaces were evaluated with scanning electron microscopy. The results showed the lowest wear rate in enamel and the highest in dentine, with the composite showing intermediate wear rates. The three-body wear results were not affected by the antagonist and showed pure wear caused by the abrasive food medium. The in vitro enamel/composite wear ratio was 2.5. The results show that tooth wear accelerates as soon as enamel disappears and dentin is exposed to composite resin. Therefore, it is important to protect dentin with a restorative material.


Asunto(s)
Resinas Compuestas/química , Materiales Dentales/química , Alisadura de la Restauración Dental/estadística & datos numéricos , Ensayo de Materiales/métodos , Dureza , Humanos , Técnicas In Vitro , Metacrilatos/química , Propiedades de Superficie
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