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1.
Shanghai Kou Qiang Yi Xue ; 29(3): 312-315, 2020 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-33043351

RESUMO

PURPOSE: To compare the aesthetic effects of all-ceramic micro-veneer and minimally invasive ultra-thin veneer in repairing deformed anterior teeth. METHODS: One hundred and twenty patients with deformed anterior teeth were selected for aesthetic restoration. According to the patient's personal condition, a suitable repair protocol was selected. Patients in the experimental group (60 cases) were repaired with all-ceramic micro-adhesive surface, while patients in the control group (60 cases) were treated with minimally invasive ultra-thin veneer. The US Public Health Administration's Evaluation Criteria (USPHS) scores were recorded and compared 6 months, 12 months, and 24 months after restoration. Statistical analysis was performed using SPSS 25.0 software package. RESULTS: There was no significant difference in the integrity, color, marginal closeness, translucency and marginal staining of the restorations between the two groups 24 months after operation (P>0.05). The satisfaction rate of the aesthetics of the experimental group was significantly lower than that of the control group (71.60% vs 93.83%, P<0.05). The incidence of complications such as broken, detached and secondary caries during the follow-up period was significantly lower in the experimental group than in the control group (1.23% vs 11.11%, P<0.05). CONCLUSIONS: The results showed that there is no significant difference in the success rate between the two methods. All-ceramic micro-veneer technique has good long-term effect, fewer complications, easy to collapse and stain the lip margin, but it has a small amount of teeth preparation and a low incidence of pulpitis in the later period. Minimally invasive super-thin veneer has high aesthetic value, so it is necessary to choose appropriate aesthetic repair methods according to the patients' needs.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Cor , Estética Dentária , Humanos
2.
Chin J Dent Res ; 23(3): 183-189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32974618

RESUMO

OBJECTIVE: To design and fabricate 3D-printed rigid constraint guides for the tooth preparation for laminate veneers and to evaluate the accuracy of guide-assisted preparation. METHODS: Twenty maxillary right central incisor resin artificial teeth were randomly divided into two equal groups and prepared for laminate veneers. Tooth preparations were performed, assisted by guides in the test group and by depth gauge burs in the control group, and both were finished by freehand operation. The typodonts were 3D scanned before preparation, after initial preparation and after final preparation. The tooth preparation depths at each step, including initial preparation depth, final preparation depth and loss of tooth tissue during polishing, were measured by 3D deviation analysis. Statistical analyses were conducted to investigate differences. RESULTS: The initial preparation depth was 0.488 mm (median, quartile 0.013 mm) in the test group and 0.521 mm (median, quartile 0.013 mm) in the control group. A statistically significant difference was found between them (P < 0.05). The final preparation depth in the test group (0.547 ± 0.029 mm) was significantly less than that in the control group (0.599 ± 0.051 mm) (P < 0.05), and closer to the predesigned value (0.5 mm). There was no statistically significant difference in the loss of tooth tissue during polishing between the test group (0.072 ± 0.023 mm) and the control group (0.089 ± 0.038 mm) (P > 0.05). CONCLUSION: In maxillary central incisors, the tooth preparation for laminate veneers could be conducted using 3D-printed rigid constraint guides, the accuracy of which is better than that of depth gauge burs.


Assuntos
Porcelana Dentária , Facetas Dentárias , Incisivo , Lasers , Preparo do Dente
3.
Rev. cient. odontol ; 8(2): e022-e022, mayo-ago. 2020. ilus
Artigo em Espanhol | LILACS, LIPECS | ID: biblio-1119300

RESUMO

El aumento en la demanda de tratamientos de odontología estética ha conducido al desarrollo de una comunicación multidisciplinaria entre las diferentes especialidades para lograr el éxito. La sonrisa gingival es un problema estético frecuente que consiste en una exposición excesiva de la encía durante la sonrisa y cuyas modalidades de tratamiento van desde una gingivectomía hasta el levantamiento de un colgajo para la remoción de hueso excedente. Las restauraciones con carillas directas de resinas compuestas son adecuadas para la conservación y la mejora estética del sector anterior, con óptima estética y durabilidad, además de ser consideradas un tratamiento mínimamente invasivo debido a sus conceptos conservadores de preservar la estructura dentaria.El presente caso clínico describe el tratamiento de un paciente joven con sonrisa gingival y alteración en forma y color de los dientes anteriores, mediante procedimientos mínimamente invasivos tales como la gingivectomía y la rehabilitación con carillas directas de resinas compuestas, con el objetivo máximo de preservar la estructura dentaria y una mayor predictibilidad estético-funcional. (AU)


The increasing demand of patients for esthetics dentistry treatments has led to the development of multidisciplinary communication between approaches among different specialties to achieve treatment success. The gummy smile is a frequent esthetic problem, which consists of excessive exposure of the gum when smiling. Treatment modalities range from gingivectomy to flap lift for the removal of excess bone. Restoration with direct veneers of composite resins is suitable for the preservation and esthetic improvement of the anterior sector, with optimal aesthetics and durability. In addition, minimally invasive treatment can be considered due to its conservative concepts of preserving the dental structure.The present case describes the treatment of a young patient with gummy smile and alteration in shape and color of the anterior teeth, through minimally invasive procedures such as gingivectomy and rehabilitation with direct veneers of composite resins with the objective of preserving the dental structure and greater esthetic - functional predictability. The present case report describes the treatment of a young patient with gummy smile. The shape and color of the anterior teeth were altered by minimally invasive procedures including gingivectomy and rehabilitation with direct veneers of composite resins with the objective of preserving the dental structure and providing greater esthetic - functional predictability. (AU)


Assuntos
Humanos , Feminino , Adolescente , Sorriso , Resinas Compostas , Facetas Dentárias , Estética Dentária , Gengivectomia , Reabilitação Bucal
4.
Rev. Odontol. Araçatuba (Impr.) ; 41(2): 15-21, maio-ago.2020. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1102664

RESUMO

Atualmente é constante a demanda por sorrisos harmoniosos nos procedimentos clínicos odontológicos, resultando em estímulos no desenvolvimento de técnicas minimamente invasivas, sistemas adesivos e materiais que sejam capazes de reproduzir as características naturais dos elementos dentários. Para as reabilitações estéticas, em especial nas unidades anteriores, os laminados cerâmicos apresentam destaque, em virtude das suas características físicas e ópticas. Como procedimento alternativo, as facetas pré-fabricadas em resina composta foram reintroduzidas na Odontologia Restauradora, exibindo versatilidade, facilidade e relação custo/benefício satisfatórias. Objetivo: Relatar um caso, demostrando uma das opções viáveis para solucionar problemas estéticos, como diastemas e desproporções dentárias. Relato de caso: A paciente procurou atendimento odontológico especializado relatando insatisfação com o sorriso. Durante avaliação, foram observados desarmonia nas proporções dentárias, diastemas múltiplos, restaurações deficientes em resina composta e fraturas nas bordas incisais. Diante disso, após o registro fotográfico, foi realizado a seleção do formato e cor das facetas pré-fabricadas, assim como, do agente de cimentação. A seguir, foi feito o isolamento relativo, remoção das restaurações deficientes e os ajustes das facetas ao dente. Para preparação da peça, foi realizado a limpeza e aplicação do adesivo; nos preparos dentários, após asperização da superfície, houve o condicionamento e aplicação do adesivo, a seguir procedeu-se a etapa de cimentação e, acabamento e polimento. Conclusão: O tratamento realizado conseguiu suprir as necessidades estéticas do sorriso da paciente, mostrando que as facetas préfabricadas em resina composta apresentam estética satisfatória, facilidade de instalação, baixo custo em relação as peças em cerâmica e conservação da estrutura dentária(AU)


Introduction: In present days, there is a constant demand for harmonious smiles in the dental clinical procedure, resulting in encouragement on development in minimally invasive techniques, adhesives systems and materials that can be capable to reproduce natural dental elements. For aesthetic rehabilitation in special in the anterior units, the ceramic laminates are highlighted due to their optical and physical features. As an alternative procedure, prefabricated composite resigns have been reintroduced into restorative dentistry, showing satisfactory versatility, ease and cost-effectiveness. Objective: Report a case, showing one of the viable options to solve aesthetical problems as diastemas and dental disproportions. Case Report: The patient sought specialized dental care reporting dissatisfaction with the smile. During evaluation, disharmony in tooth proportions, multiple diastemas, composite deficient resigns restorations and incisal edges fractures were observed. Therefore, after the photographic register, the shape and colour of the prefabricated facets, as well as cementing agent were selected. Hereinafter, relative isolation, removal of the deficient restorations and adjustments of tooth's veneers were then performed. For the piece preparation, cleaning and adhesive application were performed; on dental preparations, after the surface roughening, the adhesive was etched and applied followed by finishing and polishing cementation. Conclusion: The treatment was able to supply the aesthetical needs of the patient's smile, showing that prefabricated composite resigns veneers present satisfactory aesthetics, ease installation, low cost compared to ceramic pieces and conservation of the dental structure(AU)


Assuntos
Feminino , Adulto , Resinas Compostas , Facetas Dentárias , Diastema , Sorriso , Estética Dentária
5.
Shanghai Kou Qiang Yi Xue ; 29(2): 133-137, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32626874

RESUMO

PURPOSE: To analyze the effect of porcelain layer thicknesses and substrates on color properties and translucency of IPS e.max LT porcelain laminate veneers used to restore tetracycline stained teeth. METHODS: Porcelain specimens with different core and veneer thickness (veneer/core thickness: 0.25 mm/0.25 mm, 0.50 mm/0.25 mm, 0.25 mm/0.50 mm, 0.50 mm/0.50 mm, and 0.25 mm/0.75 mm) were fabricated by heat-press layering technique. CIE L*a*b* parameters were measured under simulated tetracycline backgrounds and black and white backgrounds by a spectrophotometer, color differences ΔE001 between specimens on simulated tetracycline backgrounds and backgrounds themselves and ΔE002 between specimens on simulated tetracycline backgrounds and white background were calculated. The translucent parameter(TP) was also calculated. The data were submitted to statistical analysis with SPSS 17.0 software package. RESULTS: ΔE001 increased with increase of thickness of the core and veneer layer, but there was no significant difference between 0.25 mm and 0.50 mm core thickness groups with 0.50 mm veneer in thickness (P>0.01). Except for light grey, ΔE002 decreased over other substrates with increase of thickness of the core and veneer layer, but there was no significant difference between 0.50 mm and 0.75 mm core thickness groups with 0.25 mm veneer in thickness (P>0.01). Both ΔE001 and ΔE002 were significantly different over different substrates(P<0.01). TP decreased as the increase of core and veneer thickness and TP was significantly different with different core and veneer thickness(P<0.01). CONCLUSIONS: Both the core/veneer thickness and the substrate have significant influence on color matching and masking ability of IPS e.max LT porcelain laminate veneers used to restore tetracycline stained teeth. As for IPS e.max LT porcelain veneers, the color property was the best when yellowish tetracycline stained teeth were restored, while the light grey was worst. The thickness of core and veneer has significant influence on the translucency of porcelain laminate veneers.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Cor , Teste de Materiais , Tetraciclina
6.
Braz Oral Res ; 34: e063, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32609232

RESUMO

This in vitro study aimed to evaluate the effects of different luting protocols on the thickness of luting interface of ceramic laminate veneers. Thirty-six lithium disilicate blocks (7 × 8 × 0.6 mm) were cemented onto bovine enamel. They were divided into 6 groups based on the luting protocol (no previous photoactivation of the dental adhesive; previous activation of the dental adhesive only on enamel surface; and previous photoactivation of the dental adhesive on both the enamel surface and inner surface of ceramic laminate) and the luting materials used (Single Bond Universal/RelyX Veneer and Tetric N Bond/Variolink Veneer). The luting interface thickness of ceramic laminate veneers was evaluated using a laser scanning confocal microscope (n = 6). The luting interface measurements were analyzed using 2-way ANOVA and the Tukey least significant difference test (α = 0.05). Prior activation of the adhesive on the dental enamel and inside the ceramic laminate exhibited higher luting interface thickness than that with no prior photoactivation of both luting materials (p < 0.05). Specimens cemented with Tetric N Bond/Variolink Veneer, submitted for prior photoactivation of the adhesive on the dental enamel and on both dental enamel and inner surface of ceramic, exhibited lower luting interface thickness than those luted with Single Bond Universal/RelyX Veneer (p < 0.05). The prior photoactivation of dental adhesives influenced the thickness of luting interface in laminate restorations. Tetric N Bond/Variolink Veneer yielded more satisfactory results than Single Bond Universal/RelyX Veneer when the adhesive was light activated.


Assuntos
Cerâmica , Animais , Bovinos , Colagem Dentária , Cimentos Dentários , Facetas Dentárias , Teste de Materiais , Cimentos de Resina
8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(6): 373-377, 2020 Jun 09.
Artigo em Chinês | MEDLINE | ID: mdl-32486565

RESUMO

The minimal tooth reduction, esthetic appeal and biocompatibility of porcelain laminate veneers have made them one of the mainstream technologies for minimal invasive esthetic dental restorations. Cementation is a crucial step in ensuring retention, marginal seal and influencing the clinical longevity of veneer restorations. Experts from Society of Prosthodontics, Chinese Stomatological Association formulated operational specifications for the cementation of porcelain laminate veneers, so as to standardize the clinical operating procedures, achieve the long-term success of veneer restorations, and promote the application of porcelain laminate veneers.


Assuntos
Cimentação , Facetas Dentárias , Porcelana Dentária , Estética Dentária
9.
J Esthet Restor Dent ; 32(5): 505-511, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32564471

RESUMO

OBJECTIVE: To assess the influence of time period on strength for different conventional Y-TZP porcelains. MATERIALS AND METHODS: Four types of porcelain were used. Porcelain powders were pressed in a steel die and fired in a furnace as recommended by the manufacturer. The blocks were sectioned into 2 mm-thick discs. Seventy specimens were fabricated from each type of porcelain. Of six jars, three contained 40 mL of dH2 O and three were dry. Ten specimens were placed in each jar and stored in an incubator at 37°C. A biaxial flexural strength test was performed for all specimens at the baseline and each succeeding year for all groups, for 3 years, using an Instron with a crosshead speed of 0.5 mm/min. RESULTS: The data were analyzed by ANOVA and Tukey at α = .05. At the baseline, the biaxial flexural strength of VitaVM9 was significantly higher than that of NobelRondo; however, there were no significant differences among Vita VM9 and Noritake CZR or NobelRondo, Lava Ceram, and Noritake CZR. There were significant reductions in the biaxial flexural strengths of all porcelains. CONCLUSIONS: After 3 years, all porcelain groups showed a significant decrease in biaxial flexural strength. The medium used is found to have no significant effects on the mean biaxial flexural strength. CLINICAL SIGNIFICANCE: Certain commercially available Y-TZP porcelains are susceptible to decrease in strength over time, which might impact the integrity of veneered zirconia restorations. This reduction in strength is among the most common reasons for the failure of veneered zirconia as reported in several studies.


Assuntos
Porcelana Dentária , Facetas Dentárias , Análise do Estresse Dentário , Resistência à Flexão , Teste de Materiais , Propriedades de Superfície , Zircônio
10.
Dent Med Probl ; 57(2): 177-183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559024

RESUMO

BACKGROUND: Yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) is used as a core material in all-ceramic restorations. The delamination and chipping of a veneering ceramic are the most common complications in the case of zirconia-based restorations. OBJECTIVES: The aim of the study was to investigate the effect of the combined treatment of the zirconium dioxide (ZrO2) surface (airborne-particle abrasion with liner application) on the shear bond strength (SBS) of a veneering ceramic. MATERIAL AND METHODS: Thirty pre-sintered ZrO2 cuboidal specimens (VITA YZ® HT) were sub-divided into 3 groups: group C consisted of 10 specimens without treatment at the sintering stage; group SZ1 consisted of 10 specimens treated with airborne-particle abrasion (50-micrometer paricles of aluminum oxide - Al2O3; Korox® 50), and then coated with a 0.1-millimeter liner (IPS e.max® Ceram ZirLiner) after sintering; group SZ2 consisted of 10 specimens treated with airborne-particle abrasion (50-micrometer particles of Al2O3), and then coated with a 0.2-millimeter liner after sintering. Ceramic veneers (IPS e.max Ceram Dentin) were then applied using the layering technique. After that, the SBS tests were conducted. RESULTS: The results showed that the combined treatment of the ZrO2 surface significantly affected SBS (p < 0.01). The highest mean value was shown in group C (12.441 ±2.284 MPa), followed by group SZ2 (7.889 ±0.794 MPa), whereas the lowest mean value was observed in group SZ1 (5.580 ±0.843 MPa). CONCLUSIONS: The combined treatment of the pre-sintered ZrO2 surface significantly reduced the SBS of a veneering ceramic. However, the combined surface treatment with a liner thickness of 0.2 mm significantly enhanced the SBS of a veneering ceramic compared to the same combined treatment but with a liner thickness of 0.1 mm.


Assuntos
Colagem Dentária , Zircônio , Cerâmica , Facetas Dentárias , Teste de Materiais , Propriedades de Superfície
11.
Int J Esthet Dent ; 15 Suppl 1: S68-S87, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32467938

RESUMO

An unfavorable relationship between the form and dimension of the dental arch and the number, dimension, and shape of the existing teeth can pose several esthetic, biologic, and functional problems. In this article, the various restorative options are discussed based on clinical and scientific evidence: Gap closure and substitution of missing teeth: restorative transformation of substituted teeth into homologous teeth with odontoplasty, direct composite, etched pieces or porcelain veneers. Gap opening and tooth replacement with all-ceramic adhesive bridges, including pontic site development. Gap distribution and restorative compensation with direct composite restorations, etched pieces or porcelain veneers. Gap shifting and restorative compensation with all-ceramic adhesive bridges, composite, etched pieces or veneers. Gap compensation by reconstructive compensation without orthodontics. The reconstructive tools including composite restorations, ceramic veneers, and adhesive bridges are discussed, and numerous cases are presented to illustrate the concepts.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Resinas Compostas , Cimentos Dentários , Estética Dentária
12.
Eur J Prosthodont Restor Dent ; 28(3): 113-120, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32363813

RESUMO

To evaluate fracture resistance of occlusal veneers made of glass-ceramic and zirconia with and without fatigue. Occlusal overlays (N=80; n=10 per group) were milled out of CAD/CAM materials, namely: a)LD:Lithium disilicate glass ceramic, b)LDS:Lithium-disilicate- strengthened aluminosilicate glass ceramic, c)ZLT:Zirconium dioxide ceramic and d)ZMT:Zirconium dioxide ceramic. The overlays were cemented on polymeric duplicates, randomly distributed to aging or non-aging conditions and loaded until fracture. Ultimate catastrophic failure strength(Fmax) and Initial crack formation load(Finitial) values were analysed using two-way ANOVA. For Finitial, material type and aging and their interaction resulted in significant values (p =⟨0.001). Finitial mean±SD values ranged from ZMTa (593 N ±205 N) to LDSb (118 N ±42 N). As for Fmax, the material type significantly affected the outcome (p⟨0.001), while aging type did not show an influence (p=0.795). The non-aged Fmax specimens values presented were: LDSa (877 N ±253 N)⟨LDa (2029 N ±412 N)⟨ZLTa (2049 N ±379 N)⟨ZMTa (2144 N ±333 N), LDSa being significantly lower (p⟨0.001). The aged Fmax values were: LDSb (1313 N ±599 N)⟨ ZLTb (1715 N ±453 N)⟨ZMTb (2018 N ±300 N)⟨LDb (2134 N ±289 N). LDS yielded significantly lower Fmax values without and non-significant less favourable results with aging. The mechanical properties following aging and lack of additional firing makes LDS an interesting restorative material for clinical application.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Desenho Assistido por Computador , Análise do Estresse Dentário , Teste de Materiais , Zircônio
13.
Dent Mater ; 36(6): 724-732, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32359850

RESUMO

OBJECTIVES: to evaluate the probability of survival and failure modes of lithium-disilicate, feldspathic-ceramic, and resin-nanoceramic anterior veneers cemented on dentin analog substrates after sliding-contact step-stress accelerated life testing (SSALT). METHODS: A virtual incisor tooth preparation was produced with a reduction of 1.5mm at the incisal edge and of 0.7mm buccally. A .STL file of the preparation was generated and CAD/CAM based G10 dentin-analog material was used for testing. Laminate veneers were milled in three different materials: lithium-disilicate (LDS, E.max CAD), resin-nanoceramic (RN, Lava Ultimate), and feldspathic-ceramic (FELDS, Vita Blocks). SSALT was employed where a spherical indenter contacted the veneer, slided along its interface with G10 to lift off and start a new cycle at 2Hz in water. Qualitative fractography was performed. The probability of survival (90% confidence-bounds) was calculated for several load/cycle missions. RESULTS: The probability of survival for a mission of 50,000 cycles decreased from 50 up to 150N equally for all groups and were not different between them. At 200N, the probability of survival was significantly lower for FELDS (10%) compared to RN veneers (41%), whereas LDS presented intermediate values (22%). The characteristic strength of RN (247N) was significantly higher than LDS (149N), and FELDS (151N). In FELDS and LDS, hackles, wake hackles and twist hackles indicated the direction of crack propagation. In RN, hackles were observed. CONCLUSIONS: Differences in probability of survival were observed only at 180 and 200N between groups. Failure modes were similar with veneer fracture down to the tooth-analog substrate.


Assuntos
Desenho Assistido por Computador , Porcelana Dentária , Cerâmica , Falha de Restauração Dentária , Análise do Estresse Dentário , Facetas Dentárias , Teste de Materiais , Reprodutibilidade dos Testes
14.
J Esthet Restor Dent ; 32(5): 487-495, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32452164

RESUMO

PURPOSE: A retrospective evaluation of extended anterior ceramic laminate veneers (EACVs) after a mean observational period of 10 years. METHODS: Thirty-one patients (20 females/11 males) underwent restoration with 101 adhesively luted, heat-pressed EACVs (maxilla, n = 65; mandible, n = 36). RESULTS: The 10 year survival rate was 91.8% (95% confidence interval [95%-CI]: 0.87;0.97). Eight ceramic fractures, one biological failure, and one change in treatment plan caused the observed failures. Seventy-seven of the 101 restorations remained intervention-free in service (success rate: 78.6% [95%-CI: 0.70;0.88]). Fourteen interventions were needed (nine recementations, two endodontic treatments, two composite fillings, and one fracture polishing). The jaw position (maxilla/mandible, survival P = .578/success P = .056) had no influence on the clinical performance. EACVs covering large areas of exposed dentin (>50%) were associated with a significantly increased risk (hazard ratio 2.98, P = .019) of needing a clinical intervention (success rate: 68.0% [95%-CI: 0.52; 0.84]). However, the degree of dentin exposure had no effect on the survival rate (P = .761). CONCLUSIONS: After a mean observational period of 10 years, mandibular and maxillary EACVs exhibited survival and success rates that were comparable. Significantly lower success rates were associated with large areas of exposed dentin (>50%). CLINICAL SIGNIFICANCE: Mandibular and maxillary EACV revealed 10-year survival rates comparable to those published for anterior metal-ceramic and glass-ceramic full-coverage crowns. Precaution should be taken not to expose dentin, and when large areas of dentin are exposed, different conditioning/luting strategies should be used.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Cimentos de Resina , Estudos Retrospectivos
15.
Int J Prosthodont ; 33(3): 307-314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32320184

RESUMO

PURPOSE: To analyze the impact of different veneering techniques on the fracture load of telescopic secondary crowns made of a high-performance polymer (Ultaire aryl ketone polymer [UAKP]). MATERIALS AND METHODS: Zirconia primary crown models (taper of 0 degrees) were prepared (N = 48), polished, scanned, and divided into four veneering groups (n = 12 each): premanufactured, digital, full anatomical, and vestibular. For all groups except vestibular, a standardized telescopic secondary crown (thickness: 0.6 mm, circular margin: 1 mm) was constructed, adapted to the corresponding primary crown, milled from UAKP, and veneered. The veneered master crown was developed based on the premanufactured group. After surface polishing, all specimens were artificially aged in a chewing simulator (1.2 million cycles, 50 N, 1.1 Hz, between 5°C and 55°C). Fracture load was tested in a universal testing machine with a piston (Ø = 6 mm, 1 mm/minute). Fracture patterns were analyzed. For statistical analysis, Kolmogorov-Smirnov test and descriptive statistics followed by one-way ANOVA with post hoc Scheffé test were conducted (P < .05). RESULTS: Significant differences in fracture load were found between different veneering techniques (P < .001), with the highest values for the vestibular and digital groups, followed by the premanufactured group. Full anatomical veneering showed the significantly lowest fracture load (1,885 ± 397 N). For all specimens, cohesive brittle fractures with similar fracture patterns occurred, irrespective of the veneering technique. CONCLUSION: The veneering technique of telescopic secondary crowns made of high-performance polymer affects overall stability. All veneering techniques provided sufficient fracture load values for telescopic secondary crowns made of UAKP. Digital veneers seem the most recommendable.


Assuntos
Porcelana Dentária , Facetas Dentárias , Coroas , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Análise do Estresse Dentário , Teste de Materiais , Polímeros , Zircônio
16.
J Prosthodont ; 29(8): 679-685, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32271486

RESUMO

PURPOSE: This study aimed to compare the load to failure and the probability of survival of porcelain fused to zirconia (PFZ) three-unit, implant-supported, fixed dental prostheses (FDPs) to those of indirect composites veneered to either zirconia (CVZ) or milled fiber-reinforced composite (FRC) frameworks under static and fatigue loading. MATERIALS AND METHODS: One-hundred and twenty posterior three-unit FDP (second premolar pontic) frameworks were fabricated via milling from a single Standard Tessellation Language (STL) file. The FDPs were divided into three groups. Each group (n = 40) was subjected to static (n = 20) and fatigue (n = 20) loading tests, as follows: (1) PFZ: zirconia framework layered with porcelain veneer; (2) CVZ: zirconia framework veneered with indirect composite resin; and (3) FRC: FRC framework veneered with indirect composite resin. After porcelain veneering onto sintered zirconia frameworks, or resin composite veneering onto zirconia or FRC frameworks, FDPs were cemented on their abutments using self-adhesive resin cement. After thermal cycling, half of the FDPs were subjected to an accelerated fatigue test. The other half of the FDPs were subjected to single load-to-failure (SLF) testing at a crosshead speed (1 mm/min). Lifetime analysis was conducted to determine the probability of survival, and fractographic analysis was performed. RESULTS: Significant differences were observed among the studied groups for SLF with the highest characteristic strength values observed for PFZ (2154 N), followed by 1905.47 N for CVZ and 1679.56 N for FRC. The probability of survival for 100,000 cycles at 500 N was the highest for FRC (98%) and CVZ (100%) and was significantly lower for PFZ (88%). Different fracture patterns were observed in the fractography. CONCLUSIONS: In fatigue testing, which simulates masticatory function better than static tests, a higher probability of survival was observed for FRC and CVZ than for PFZ. Framework fractures were not observed only for the FRC group, indicating that chairside repair with the addition of indirect composite could be performed for continued function.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Desenho Assistido por Computador , Materiais Dentários , Porcelana Dentária , Falha de Restauração Dentária , Análise do Estresse Dentário , Facetas Dentárias , Teste de Materiais , Zircônio
17.
Gen Dent ; 68(3): 34-39, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348241

RESUMO

This case report describes the treatment of a patient who had molar-incisor hypomineralization associated with dental fluorosis, a diagnosis established through a comprehensive review of the clinical record, an intraoral clinical examination, and assessment of photographic records. First, dental hypersensitivity was treated with fluoride varnish, which was applied separately to each dental quadrant. Subsequently, the functional and esthetic reconstruction of the permanent maxillary central incisors was completed in a single session through the placement of direct composite resin veneers. After the treatment, the patient was reexamined monthly for 12 months to evaluate the durability of the restorations. At the 12-month follow-up, no fractures or pigmentations were observed, and only a slight loss of brightness of the restorations was noted. The dental hypersensitivity had been eliminated. When an adhesive restorative technique with composite resin is well executed, it is possible to obtain satisfactory and long-lasting esthetics and relief of painful symptoms.


Assuntos
Hipoplasia do Esmalte Dentário , Fluorose Dentária/terapia , Resinas Compostas , Restauração Dentária Permanente , Facetas Dentárias , Estética Dentária , Humanos , Incisivo , Dente Molar
18.
J Esthet Restor Dent ; 32(4): 424-432, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32270920

RESUMO

OBJECTIVE: This in vitro study aims to evaluate load-to-failure of ceramic veneers with butt joint (BJ) and feathered edge (FE) incisal preparation designs, and to correlate these results to the failure mode of the restorations. MATERIALS AND METHODS: One hundred and forty-eight typodont teeth (customized Nissin A25A-UL19B) were divided into two different preparation configurations BJ and FE and two different loading angulations, 0° and 20°. Lithium disilicate ceramic veneers (IPS e.max CAD, Ivoclar Vivadent) were milled using computer-aided-design-and-computer-aided-manufacturing (CAD/CAM) techniques. Veneers were bonded to typodont teeth with resin cement (IPS Variolink Esthetic, Ivoclar Vivadent). Each group was loaded at the incisal edge using an Instron Universal Testing Machine at a crosshead speed of 0.01 mm/s till failure. RESULTS: Pairwise comparison showed veneers from the BJ groups had a significantly higher load-to-failure value compared to the FE groups. Veneers with a FE preparation design loaded at 20° angulation had the lowest load-to-failure value. CONCLUSIONS: Within the limitations of the present study, both incisal preparation designs and loading angulations have significant effects on the load-to-failure values of ceramic veneers. BJ group exhibits a significantly higher load-to-failure value compared to the FE group. CLINICAL SIGNIFICANCE: BJ incisal preparation is preferred over FE preparation design.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Desenho Assistido por Computador , Falha de Restauração Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina
19.
Oper Dent ; 45(5): 467-472, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32243254

RESUMO

This article describes an indirect composite restoration technique for diastema closure and tooth lengthening with a noninvasive approach using regularly available materials such as silicone, composite resin, and an adhesive system. The procedure resulted in occlusal and functional improvement, with diastema closure, protrusive guide adjustment, and an increase in central incisor length. The procedure provided an adequate proportion of the central incisors with an esthetically natural appearance. It also resulted in simple, fast, and accurate manufacturing with a noninvasive esthetic indirect rehabilitation compared with more invasive preparation of ceramic veneers.


Assuntos
Facetas Dentárias , Diastema , Resinas Compostas , Diastema/terapia , Estética Dentária , Humanos , Incisivo
20.
Braz Dent J ; 31(1): 69-77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159709

RESUMO

The objective was to evaluate the color stability of ceramic veneers luted with resin cements and pre-heated composite resins (60oC) for 12 months, and determine the degree of conversion (DC) of the luting agents. Two resin cements (AllCem Veneer, light-cured (LRC) and AllCem, dual-cured (DRC)] and three composite resins [Z100 (MNCR-minifilled), Herculite Classic (MHCR-micro-hybrid) and Durafill (MCCR-microfilled)] were used for cementing 0.8-mm-thick lithium-silicate glass-ceramic laminates (Suprinity, shade B2-HT, Vita) on bovine enamel (n=10). The specimens were stored at 37oC in distilled water. CIELab parameters were determined at 24h after luting (baseline), 7, 30, 90, 180 days and 12 months. Three specimens were prepared for DC evaluation, performed by micro-Raman spectroscopy. Data were analyzed by ANOVA and Tukey's test (a=5%). For ΔEab and ΔE00, there were significant differences for luting material (p<0.001), time (p<0.001), and double interaction (p<0.001). The groups cemented with MHCR (1 year), MCCR (90 days and 1 year) and MCCR-PH (1 year) were the ones with ΔE values greater than the acceptability threshold. All other groups maintained their ΔE lower than the acceptability threshold after 1 year in distilled water. Regarding DC, there were no significant differences (p=0.127) among the materials. Non-significant negative correlations were observed between the mean ΔEab and DC (R=-0.65) and ΔE00 and DC (R=-0.64). A significant positive correlation was observed mean ΔEab and ΔE00 (R=0.99). It was concluded that the different luting agents influenced the final color of the restorations. The heating of the composite resins did not affect their DC.


Assuntos
Cerâmica , Cimentos de Resina , Animais , Bovinos , Cor , Resinas Compostas , Porcelana Dentária , Facetas Dentárias , Seguimentos , Teste de Materiais
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