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1.
Clin Implant Dent Relat Res ; 20(2): 170-179, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29210181

RESUMO

OBJECTIVES: Implant supported single metal-ceramic crowns cemented either extraorally or intraorally were comparatively evaluated by clinical, radiologic, biomarker, and microbiological parameters. MATERIALS AND METHODS: Twelve patients with bilateral single tooth gap in the maxillary posterior region received two locking-taper implants; 4.5 mm width, 8 mm length. Selection of intraoral (IOC) or extraoral cementation (EOC) using screwless titanium abutments was done randomly. Peri-implant crevicular fluid (PICF), gingival crevicular fluid (GCF) samples were collected from the implants, adjacent teeth, and bleeding on probing, soft tissue thickness, keratinized tissue width were recorded before starting the prosthetic procedures (baseline) and 3, 6 months after implant loading. Crestal bone loss was measured on radiographs taken immediately and 6 months after cementation. Cytokine levels, amounts of bacteria were determined in PICF/GCF samples. Data were tested by appropriate statistical analyses. RESULTS: Clinical findings were similar in the crowns cemented extraorally or intraorally at all times (P < .05). PICF and GCF data were similar. At 3 month, interleukin-17E and osteoprotegerin levels were lower in the intraorally cemented crowns. CONCLUSION: Extraorally and intraorally cemented crowns exhibited similar crestal bone loss after loading. Higher amount of osteoprotegerin at 3 month at the EOC than the IOC sites might bode well for good osseointegration.


Assuntos
Cimentação/métodos , Coroas , Prótese Dentária Fixada por Implante , Perda do Osso Alveolar , Biomarcadores/análise , Coroas/microbiologia , Citocinas/análise , Líquido do Sulco Gengival/química , Líquido do Sulco Gengival/microbiologia , Humanos , Osteoprotegerina/análise , Ligante RANK/análise , Titânio
2.
Quintessence Int ; 47(6): 461-71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26949761

RESUMO

OBJECTIVES: The aims of this clinical study were to compare internal three-dimensional (3D) adaptation of porcelain laminate veneers (PLV) with minimal tooth preparation and without tooth preparation (prepless) and to evaluate the clinical outcomes at baseline and following 6, 12, and 24 months after luting. METHOD AND MATERIALS: Thirty-one prepless PLV and 31 PLV with minimal tooth preparation were fabricated using lithium disilicate glass-ceramic material and placed in 12 patients (8 women, 4 men; 18 to 40 years old). All PLV were luted with an adhesive luting system (Variolink veneer). A silicone replica was obtained to measure internal adaptation of each PLV using a low viscosity polyvinyl siloxane impression material just before luting. Silicone replicas were scanned in x-ray micro computerized tomography (micro CT). Clinical evaluations took place at baseline (2 days after luting) and following 6, 12, and 24 months after luting. Marginal integrity, marginal discoloration, secondary caries, tooth sensitivity, and fracture were evaluated following FDI criteria. Replica scores were analyzed using Mann-Whitney U and Student's t test (α = .05). Kaplan-Meier statistical analysis was done for the survival rate of PLV. FDI criteria scores were analyzed using Pearson's chi-square test (α = .05). RESULTS: The median marginal gaps for PLV-without-tooth-preparation and PLV-with-minimal-tooth-preparation groups were 100 µm and 140 µm respectively. There was a statistically significant difference between the two groups with respect to marginal gap (P = .04). The mean internal adaptation for the PLV-without-tooth-preparation group was 217.17 ± 54.72 µm, and was 170.67 ± 46.54 µm for the PLV-with-minimaltooth- preparation group. There was a statistically significant difference between the two groups (P = .001). Based on FDI criteria, 100% of the PLV were rated satisfactory during the 2-year period. CONCLUSIONS: In this in-vivo study, mean and median values of marginal gap and internal adaptation for PLV with minimal tooth preparation and PLVs without tooth preparation were within a clinically acceptable range. A 100% success rate was recorded for all PLV during the 2-year period.


Assuntos
Porcelana Dentária , Facetas Dentárias , Preparo Prostodôntico do Dente , Adolescente , Adulto , Colagem Dentária/métodos , Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Estética Dentária , Feminino , Humanos , Incisivo , Masculino , Maxila , Cimentos de Resina , Resultado do Tratamento , Microtomografia por Raio-X
3.
Quintessence Int ; 46(8): 691-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25988191

RESUMO

OBJECTIVE: A long-term clinical study previously stated that adhesively luted resin-bonded fixed partial dentures (RBFPDs) with two retainers exhibited two complications (loss of adhesion or fracture between retainer and pontic) when compared to RBFPDs with a single retainer. The reasons for these complications were not reported. The aim of this study was to evaluate the stress distribution of two-retainer and singleretainer zirconium dioxide RBFPDs by using three-dimensional finite element analysis (3D FEA). METHOD AND MATERIALS: Two different 3D finite element models were created. Each model contained cortical bone, cancellous bone, periodontal ligament, cement, and enamel. Additionally one of the models contained a two-retainer zirconium dioxide RBFPD while another contained a single-retainer zirconium dioxide RBFPD. A 100 N force was applied at 45 degrees 2 mm below the incisal edge of the palatal surface of the pontic. In each model, Von Mises stress distribution was evaluated. RESULTS: Maximum Von Mises stress values in RBFPD with a single retainer and two retainers were 1.13 MPa and 1.23 MPa, respectively. Von Mises stress was concentrated at the interface between pontic and retainer for RBFPD with two retainers. CONCLUSION: Zirconium dioxide RBFPD with a single retainer and two retainers exhibited similar stress concentrations between pontic and retainer. However, the use of a single retainer for RBFPDs prevented stress concentration at the interface between retainer and pontic.


Assuntos
Análise do Estresse Dentário/métodos , Prótese Adesiva , Cerâmica , Falha de Restauração Dentária , Planejamento de Dentadura , Retenção de Dentadura , Prótese Parcial Fixa , Análise de Elementos Finitos , Humanos , Teste de Materiais , Modelos Dentários , Software , Zircônio
4.
J Prosthodont ; 24(5): 345-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25220298

RESUMO

PURPOSE: The aims of this randomized-controlled clinical trial were to compare marginal and internal adaptation of all-ceramic crowns fabricated with CAD/CAM and heat-pressed (HP) techniques before luting and to evaluate the clinical outcomes at baseline and at 6, 12, and 24 months after luting. MATERIALS AND METHODS: Fifteen CAD/CAM (CC) and 15 HP all-ceramic crowns were placed in 15 patients. A silicone replica was obtained to measure marginal and internal adaptation of each all-ceramic crown before luting, and they were sectioned buccolingually and mesiodistally. Marginal and internal adaptations were measured using computerized light microscope at 40× magnification. Clinical evaluations took place at baseline (2 days after luting) and at 6, 12, and 24 months after luting. Replica scores were analyzed with Mann-Whitney U and Student's t-test (α = 0.05). Survival rate of crowns was determined using Kaplan-Meier statistical analysis. RESULTS: The median marginal gap for the CC group was 132.2 µm and was 130.2 µm for the HP group. The mean internal adaptation for the CC group was 220.3 ± 51.3 µm and 210.5 ± 31 µm for the HP group. There were no statistically significant differences with respect to marginal opening (Mann-Whitney U test; p = 0.95) and internal adaptation (Student's t-test; p = 0.535) between the 2 groups. Based on modified Ryge criteria, 100% of the crowns were rated satisfactory during the 2-year period. CONCLUSION: In this in vivo study, CAD/CAM and HP all-ceramic crowns exhibited similar marginal and internal adaptations. A 100% success rate was recorded for the 15 CAD/CAM and for the 15 HP all-ceramic crowns during the 2-year period.


Assuntos
Coroas , Desenho Assistido por Computador , Adaptação Marginal Dentária , Porcelana Dentária , Planejamento de Prótese Dentária , Humanos
5.
Quintessence Int ; 46(3): 189-97, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25529004

RESUMO

OBJECTIVE: The aim of this prospective clinical study was to evaluate the clinical performance of lithium disilicate allceramic crowns for a period from 12 to 156 months. METHOD AND MATERIALS: One hundred and twenty five lithium disilicate all-ceramic crowns were placed in 35 patients between 2001 and 2007. One patient who received four all-ceramic crowns was excluded from the study. The remaining 34 patients received 121 all-ceramic crowns and were recalled. Ninety-eight anterior and 23 posterior crowns were inserted. All crowns were applied on vital teeth except for 11 crowns which were placed on endodontically treated teeth. Follow-up appointments were performed 6 months after insertion, then annually. Replacement of a restoration was defined as failure. Marginal integrity, marginal discoloration, secondary caries, sensitivity, color match, and ceramic surface were evaluated following modified California Dental Association/Ryge criteria. The survival rate of the crowns was determined using Kaplan- Meier statistical analysis and log-rank test (P = .05). RESULTS: Ten crowns were fractured. The cumulative survival rate according to Kaplan-Meier was 87.1% after mean 104.6 months (range 12 to 156 months). Location (anterior vs posterior) of all-ceramic crown did not significantly affect the survival rate according to log-rank test (P = .89). Endodontically treated teeth without post-and-core restorations exhibited a higher failure rate after all-ceramic crown application according to log-rank test (P < .001). CONCLUSION: In this in vivo study, lithium disilicate all-ceramic crowns exhibited a satisfactory clinical performance with an estimated survival probability of 87.1% over 104.6 months and they can be used clinically in the anterior and posterior region. Restoring endodontically treated teeth with post-and-core restorations should be considered before all-ceramic crown application.


Assuntos
Coroas , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Adulto , Silicatos de Alumínio , Adaptação Marginal Dentária , Porcelana Dentária , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
6.
J Prosthet Dent ; 112(4): 909-13, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24819532

RESUMO

STATEMENT OF PROBLEM: Metal ceramic crowns are widely used in clinical practice, but comparisons of the clinical adaptation of restorations made with different processing techniques are lacking. PURPOSE: The purpose of this study was to compare the clinical marginal and internal adaptation of metal ceramic crowns fabricated with 3 different techniques: computer-aided design and computer-aided manufacturing (CAD/CAM) milling (CCM), direct metal laser sintering (DMLS), and traditional casting (TC). MATERIAL AND METHODS: Twenty CCM, 20 DMLS, and 20 TC metal ceramic crowns were fabricated for 42 patients. Before luting the crowns, silicone replicas were obtained to measure marginal gap and internal adaptation that was evaluated at 3 regions: axial wall, axio-occlusal angle, and occlusal surface. Measurements were made with a reflected light binocular stereomicroscope at 20× magnification and analyzed with 1-way analysis of variance (ANOVA) and the Bonferroni post hoc test (α=.05). RESULTS: The mean marginal gap values were 86.64 µm for CCM, 96.23 µm for DMLS, and 75.92 µm for TC. The means at the axial wall region were 117.5 µm for the CCM group, 139.02 µm for the DMLS group, and 121.38 µm for the TC group. One-way ANOVA revealed no statistically significant differences among the groups for measurements at the marginal gap (P=.082) and the axial wall region (P=.114). The means at the axio-occlusal region were 142.1 µm for CCM, 188.12 µm for DMLS, and 140.63 µm for TC, and those at the occlusal surface region were 265.73 µm for CCM, 290.39 µm for DMLS, and 201.09 µm for TC. The mean values of group DMLS were significantly higher at the axio-occlusal region and the occlusal surface region than those of other groups (P<.05). CONCLUSIONS: CCM, DMLS and TC metal ceramic crowns performed similarly in terms of clinical marginal and axial wall adaptation. The cement film thickness at the occlusal region and axio-occlusal region were higher for DMLS crowns.


Assuntos
Desenho Assistido por Computador , Coroas , Adaptação Marginal Dentária , Planejamento de Prótese Dentária , Lasers , Ligas Metalo-Cerâmicas/química , Adolescente , Adulto , Idoso , Ligas de Cromo/química , Técnica de Fundição Odontológica , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Fotografação/métodos , Cimento de Policarboxilato/química , Propriedades de Superfície , Adulto Jovem
7.
Int J Prosthodont ; 25(2): 135-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22371833

RESUMO

The aim of this study was to compare quantitatively the masticatory performance of patients with overdentures supported by two implants, conventional complete dentures, and natural dentitions. Each patient was asked to chew a gelatin cube. The collected remains of the test food (gelatine cube) were fractioned by a sieving procedure and weighed. Maximum mouth opening and masticatory area were measured using kinesiography. There were statistically significant differences among groups with respect to masticatory performance using a 3.15-mm-diameter sieve (P < .001) and 0.5-mm-diameter sieve (P < .001), masticatory area (P = .019), and maximum mouth opening (P < .001). Increasing retention of a mandibular complete denture with two implants improved masticatory performance.


Assuntos
Prótese Dentária Fixada por Implante , Dentição , Prótese Total , Revestimento de Dentadura , Mandíbula/fisiologia , Mastigação/fisiologia , Implantes Dentários , Retenção de Dentadura , Feminino , Gelatina , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Tamanho da Partícula , Amplitude de Movimento Articular/fisiologia
8.
J Appl Biomech ; 28(4): 394-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21904010

RESUMO

The purpose of this study was to compare the fracture resistance and fracture mode of single implant-zirconium coping combinations using zirconium and titanium abutments and to analyze the stress distribution pattern using three-dimensional finite elements analysis. Twenty implants with titanium and zirconium abutments were randomly divided into two groups (n = 10) and into resin blocks. Zirconium copings were cemented onto the abutments. The specimens were loaded with 135° angles to the long axis and the load values at the moment of failure were recorded using a universal test machine. Stress levels were calculated according to the maximum Von Mises criteria. The fracture resistances for titanium and zirconium abutment groups were 525.65 N and 514.05 N, respectively. No significant differences were observed between two groups regarding the fracture resistance levels. The maximum Von Mises equivalent stress concentrated on zirconium copings in both of the groups. Implant-abutment-ZrO2 coping combination has the potential to withstand physiological occlusal forces in the anterior region. Three-dimensional finite elements analysis results of the implant-abutment-ZrO2 coping combination is compatible with the results of fracture resistance.


Assuntos
Cerâmica/química , Implantes Dentários para Um Único Dente , Zircônio/química , Força Compressiva , Módulo de Elasticidade , Análise de Falha de Equipamento , Teste de Materiais , Desenho de Prótese , Estresse Mecânico , Resistência à Tração
9.
Eur J Prosthodont Restor Dent ; 18(1): 2-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20397495

RESUMO

The aim of this study was to investigate the effect of one particular brand of post and core system (ER Post) consisted of different post and core materials on the fracture resistance of endodontically treated teeth. Fifty caries-free maxillary central incisors were randomly assigned to five groups (n=10). All teeth were sectioned at the cemento-enamel junction except for the teeth in the control group. Four experimental groups consisted of cast gold post-and-core group (GG), Heraplat post/cast gold core group (HG), titanium post/composite core (TC), and titanium post/cast gold core (TG). The control group (ETT) consisted of endodontically treated teeth without posts. All posts were cemented in the roots with zinc phosphate cement. Following thermal cycling (5000 cycles between 5 degrees C and 55 degrees C with a dwell time of 30 seconds) a static load was applied to 2 mm below the incisal edge on the palatal surface of each specimen until they were fractured. Fracture data obtained and statistically analyzed with one-way ANOVA and a Tukey's test (p<0.05). Means of the fracture resistance during static loading were: 423.76 N (GG), 529.46 N (HG), 389.08 N (TC), 408.7 N (TG), 404.4 N (ETT, control). Heraplat post with cast gold core exhibited the highest fracture load than the other groups (p<0.05). Specimens in groups HG and ETT (control) showed the most repairable failure. Heraplat post with cast gold core had the highest fracture resistance of endodontically treated teeth.


Assuntos
Ligas Dentárias/química , Técnica para Retentor Intrarradicular , Fraturas dos Dentes/fisiopatologia , Dente não Vital/fisiopatologia , Cimentação , Resinas Compostas/química , Materiais Dentários/química , Ligas de Ouro/química , Humanos , Incisivo/fisiopatologia , Teste de Materiais , Metacrilatos/química , Técnica para Retentor Intrarradicular/instrumentação , Preparo de Canal Radicular/instrumentação , Estresse Mecânico , Temperatura , Fatores de Tempo , Titânio/química , Cimento de Fosfato de Zinco/química
10.
Eur J Prosthodont Restor Dent ; 18(1): 23-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20397499

RESUMO

This in vitro study evaluated the effects of the different endodontic posts and surface conditioning on the fracture resistance and fracture modes of endodontically treated teeth. The experimental groups consisted of zirconia ceramic post with a glasss-ceramic core [A], zirconia ceramic post with a composite core [B], glass fiber composite post (FRC) with a composite core [C], and titanium post with a composite core [D]. All posts in these groups were cemented with self-adhesive resin cement (Rely X Unicem Aplicap) combination with tribochemical silica coating (TSC). Groups E, F, G and H comprised the same post-and-core materials as the first 4 groups but cemented with the same resin cement without TSC. Specimens were subjected to thermal cycling between 5 degrees C and 55 degrees C for a total of 5000 cycles with 30s per cycle. Static load was applied to the palatal surface of each specimen until they were fractured. Statistical analysis was conducted using analysis of variance (ANOVA) followed by post-hoc comparisons (Tukey). The fracture resistance was significantly affected by the post material (P < 0.001) and surface conditioning (P < 0.001; two-way ANOVA). The application of TSC to post surface decreased the fracture resistance of zirconia ceramic post with composite core (p=0.002; Tukey) and glass FRC post with composite core (p=0.029; Tukey). No catastrophic failure was observed for groups B, C, D, E, F and G. Under the testing conditions used, the titanium post/composite core that had been silicoated exhibited the highest fracture resistance.


Assuntos
Materiais Dentários/química , Planejamento de Prótese Dentária , Técnica para Retentor Intrarradicular/instrumentação , Fraturas dos Dentes/fisiopatologia , Dente não Vital/fisiopatologia , Silicatos de Alumínio/química , Cimentação , Cerâmica/química , Resinas Compostas/química , Corrosão Dentária/instrumentação , Corrosão Dentária/métodos , Porcelana Dentária/química , Análise do Estresse Dentário/instrumentação , Adesivos Dentinários/química , Resinas Epóxi/química , Vidro/química , Humanos , Incisivo , Teste de Materiais , Cimentos de Resina/química , Preparo de Canal Radicular/instrumentação , Preparo de Canal Radicular/métodos , Silanos/química , Dióxido de Silício/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo , Titânio/química , Preparo do Dente/métodos , Zircônio/química
11.
J Adhes Dent ; 11(4): 299-303, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19701511

RESUMO

PURPOSE: The effect of three different bonding strategies on the shear bond strength of a resin composite to fluorotic enamel surfaces was investigated. MATERIALS AND METHODS: Thirty-six noncarious extracted human molars with fluorosis and 36 without fluorosis were scraped clean from any remaining tissue, and then were divided into three subgroups according to the tested dentin bonding systems. The resin composite was bonded to the teeth using three different adhesive systems: Peak LC Bond with an etch-and-rinse technique (Ultradent Products), Peak LC Bond with a self-etching technique using Peak SE Primer (Ultradent Products), and Xeno V (Dentsply Caulk) using a one-bottle self-etching technique. Following the photopolymerization of the resin composites, thermocycling was performed 5000 times. Shear bond strengths were tested using the Shimadzu Universal Testing Machine until failure. The analysis of the fractured enamel surfaces was performed using an optical microscope (Nikon ECLIPSE ME 600) at 10X and 1000X magnification, and the images were analyzed with an image analyzer (LUCIA 4.21). The data obtained were analyzed with two-way ANOVA and the Bonferroni test at a significance level of p < 0.05. RESULTS: Mean shear bond strengths in MPa of the groups were: Peak LC Bond, self-etching, on fluorotic enamel 13.23 +/- 2.58 and on nonfluorotic enamel 17.81 +/- 2.90; Peak LC Bond, etch-and-rinse, on fluorotic enamel 16.77 +/- 2.32 and on nonfluorotic enamel 21.13 +/- 2.74; one-bottle self-etching Xeno V on fluorotic enamel 10.79 +/- 2.14 and on nonfluorotic enamel 14.58 +/- 2.99. CONCLUSION: Fluorosis adversely affected the bonding performance of all the bonding systems to enamel. The use of the etch-and-rinse dentin bonding technique produced higher bond strengths of the resin composite tested to fluorotic and nonfluorotic enamel compared to both self-etching techniques.


Assuntos
Colagem Dentária/métodos , Cimentos Dentários/química , Esmalte Dentário/ultraestrutura , Adesivos Dentinários/química , Fluorose Dentária/patologia , Condicionamento Ácido do Dente , Compômeros/química , Resinas Compostas/química , Materiais Dentários/química , Análise do Estresse Dentário/instrumentação , Humanos , Processamento de Imagem Assistida por Computador , Teste de Materiais , Metacrilatos/química , Ácidos Fosfóricos/química , Polímeros/química , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo
12.
J Adhes Dent ; 10(5): 373-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19058683

RESUMO

PURPOSE: To examine the effect of different adhesive luting systems on the shear bond strength of all-ceramic restorations to dentin surfaces. MATERIALS AND METHODS: Forty-eight all-ceramic disks (2 x 3 mm; IPS e.max Press) were fabricated. Forty-eight noncarious extracted human molars were divided into 4 groups. in groups 1 to 4, IPS e.max Press disks were luted with Variolink 2/Excite DSC (etch-and-rinse), Clearfil Esthetic Cement/Clearfil Protect Bond (antibacterial and self-etching), Multilink/Multilink Primer (self-etching), or Multilink Sprint (self-adhesive). All specimens were subjected to 5000 thermocycles (5 degrees C to 55 degrees C, 30-s dwell time). Shear bond strengths were tested using a universal testing machine until failure. The analysis of the fractured dentin surfaces was performed using an optical microscope at 10X and 1000X magnification; the images were analyzed with an image analyzer. Data were analyzed with one-way ANOVA and Tukey's test at a significance level of p < 0.05. RESULTS: Mean shear bond strength data of the groups in MPa were: Variolink 2/Excite DSC: 25.89 +/- 3.71; Clearfil Esthetic Cement/Clearfil Protect Bond: 17.21 +/- 2.71; Multilink/Multilink Primer: 11.6 +/- 3.51; Multilink Sprint: 10.4 +/- 3.15. According to the one-way ANOVA, there were significant differences in shear bond strength (p < 0.001). According to Tukey's test, statistically significant differences were observed in shear bond strength between groups 1 and 2 (p < 0.001), groups 1 and 3 (p < 0.001), groups 1 and 4 (p < 0.001), groups 2 and 3 (p = 0.003), and groups 2 and 4 (p < 0.001). CONCLUSION: The etch-and-rinse dentin bonding system produced higher bond strengths of all-ceramics to dentin surfaces than did the self-etching bonding systems and self-adhesive luting system.


Assuntos
Colagem Dentária , Cimentos Dentários/química , Porcelana Dentária/química , Dentina/ultraestrutura , Adesivos Dentinários/química , Humanos , Processamento de Imagem Assistida por Computador , Teste de Materiais , Metacrilatos/química , Dente Molar , Cimentos de Resina/química , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo
13.
J Dent ; 36(4): 281-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18289768

RESUMO

OBJECTIVES: Effect of different adhesive luting systems on the shear bond strength of IPS Empress 2 ceramic restorations to fluorosed enamel surface was investigated. METHODS: Forty-eight ceramic discs (2 mm x 3 mm; IPS Empress 2) were fabricated. Twenty-four non-carious extracted human molar teeth with fluorosis and 24 without fluorosis were cleaned with pumice using a plastic brush and then they were divided into two main groups. The IPS Empress 2 ceramic discs were luted to the teeth of four subgroups with two different adhesive luting systems, Variolink 2/Excite DSC (etch-and-rinse) and Clearfil Esthetic Cement/ED Primer II (self-etch), thermocycling was performed 5000 times. Shear bond strengths were tested using Shimadzu Universal Testing Machine until failure. An optical microscope and image analyzer were used at 10x and 1000x magnification to analyze the surfaces for adhesive, cohesive and mixed failure percentages. Data was analyzed with one-way ANOVA and Tukey test at a significance level of p<0.05. RESULTS: Mean shear bond strength data of the groups in MPa were; Variolink 2/Excite DSC on fluorosed enamel: 18.3+/-3.08, Variolink 2/Excite DSC on non-fluorosed enamel: 18.79+/-2.65, Clearfil Esthetic Cement/ED Primer II on fluorosed enamel: 8.43+/-2.45, Clearfil Esthetic Cement/ED Primer II on non-fluorosed enamel: 13.53+/-1.68. Mixed failure was the most prevalent type of failure in moderate fluorosed and non-fluorosed teeth with etch-and-rinse dentin bonding system, and in fluorosed teeth with self-etch dentin bonding system. CONCLUSIONS: The use of an etch-and-rinse adhesive luting procedure produced higher bond strengths of glass-ceramics bonded to fluorosed and non-fluorosed enamel surfaces than the self-etch bonding system.


Assuntos
Colagem Dentária , Porcelana Dentária , Fluorose Dentária , Cimentos de Resina , Corrosão Dentária/métodos , Falha de Restauração Dentária , Restauração Dentária Permanente , Análise do Estresse Dentário , Humanos , Compostos de Lítio , Dente Molar , Resistência ao Cisalhamento
14.
J Adhes Dent ; 9(1): 39-47, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17432400

RESUMO

PURPOSE: In this in-vitro study, microleakage of all-ceramic crowns was evaluated at enamel and dentin margins. MATERIALS AND METHODS: Forty maxillary central incisors were randomly divided into 4 groups (n = 10). While buccal and palatal margins were placed on enamel, mesial and distal margins were placed below the cementoenamel junction. In groups 1 to 3, IPS Empress 2 crowns were luted with Variolink 2/Syntac Classic (group 1), Bifix DC/Solobond Plus (group 2) and Calibra/Prime & Bond NT combinations (group 3), respectively. In the control group (group 4), porcelain-fused-to-metal crowns were luted with a zinc-phosphate cement. All specimens were subjected to 5000 thermocycles (at 5 degrees C to 55 degrees C; 30-s dwell time). After immersion in India ink for 48 h at 37 degrees C, the specimens were sectioned both buccolingually and mesiodistally. Each section was evaluated for microleakage under a stereomicroscope at 24X magnification. RESULTS: According to the Krukal-Wallis test, in all groups, there were significant differences in microleakage at the enamel margins (p = 0.001). Nevertheless, the margins finished in dentin showed no significant differences (p = 0.163). According to the Mann-Whitney U-test, statistically significant differences were observed in microleakage between groups 1 and 3 (p = 0.049), groups 1 and 4 (p = 0.001), groups 2 and 4 (p = 0.002), and between groups 3 and 4 (p = 0.045) at the enamel margin. In group 1, significantly greater microleakage was observed at the dentin margin compared to the enamel margin (p = 0.007). CONCLUSION: The adhesive luting technique demonstrated an excellent ability to minimize microleakage of all-ceramic crowns at the enamel margins. Water-based dentin bonding systems showed less microleakage than the water-free acetone-based dentin bonding system at the enamel margin.


Assuntos
Coroas , Infiltração Dentária/classificação , Porcelana Dentária/química , Cimentos de Resina/química , Acetona/química , Carbono , Corantes , Resinas Compostas/química , Esmalte Dentário/ultraestrutura , Dentina/ultraestrutura , Humanos , Compostos de Lítio/química , Teste de Materiais , Ligas Metalo-Cerâmicas/química , Metacrilatos/química , Ácidos Polimetacrílicos/química , Solventes/química , Propriedades de Superfície , Temperatura , Fatores de Tempo , Colo do Dente/ultraestrutura , Água/química , Cimento de Fosfato de Zinco/química
15.
Int J Prosthodont ; 20(2): 168-72, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17455438

RESUMO

PURPOSE: The aim of this study was to evaluate the clinical performance of all-ceramic crowns made with the IPS Empress 2 system after an observation period of 12 to 60 months. MATERIALS AND METHODS: Seventy-nine IPS Empress 2 crowns were placed in 21 patients. The all-ceramic crowns were evaluated clinically, radiographically, and using clinical photographs. The evaluations took place at baseline (2 days after cementation) and at 6-month intervals for 12 to 60 months. Survival rate of the crowns was determined using Kaplan-Meier statistical analysis. RESULTS: Based on the US Public Health Service criteria, 95.24% of the crowns were rated satisfactory after a mean follow-up period of 58 months. Fracture was registered in only 1 crown. One endodontically treated tooth failed as a result of fracture at the cervical margin area. CONCLUSION: In this in vivo study, IPS Empress 2 crowns exhibited a satisfactory clinical performance during an observation period ranging from 12 to 60 months.


Assuntos
Coroas , Porcelana Dentária/química , Compostos de Lítio/química , Adolescente , Adulto , Cor , Resinas Compostas/química , Coroas/normas , Colagem Dentária , Materiais Dentários/química , Planejamento de Prótese Dentária , Falha de Restauração Dentária , Feminino , Seguimentos , Vidro/química , Humanos , Masculino , Pessoa de Meia-Idade , Técnica para Retentor Intrarradicular/instrumentação , Propriedades de Superfície , Análise de Sobrevida , Colo do Dente/lesões , Fraturas dos Dentes/etiologia , Preparo Prostodôntico do Dente , Dente não Vital/terapia
16.
J Dent ; 34(6): 372-80, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16288949

RESUMO

OBJECTIVES: Effect of a dentin adhesive system containing antibacterial monomer-MDPB (Clearfil Protect Bond) on the shear bond strength of all-ceramic-IPS Empress 2 restorations luted with three different dual-polymerizing systems (Variolink 2, RelyX ARC and Panavia F 2.0) to dentin was investigated. METHODS: One hundred and eight all-ceramic discs (2 x 3mm; IPS Empress 2) were fabricated and ultrasonically cleaned. The buccal surfaces of 108 non-carious extracted human premolars were flattened to expose dentin and subsequently polished with 600-grit wet silicon carbide paper. Three dual-polymerizing luting systems had test groups and control groups consisting of 18 samples each. For the test groups Clearfil Protect Bond was applied to the exposed dentin surfaces. Control groups received the original bonding procedures of each adhesive system. After the all-ceramic samples were luted to the teeth, thermocycling was performed 5000 times. Shear bond strengths were tested using Shimadzu Universal Testing Machine until failure. Analysis of fractured dentin surfaces were performed using Optical Microscope at x10 and x1000 magnifications and the images were analyzed with Image Analyzer. Data was analyzed with one-way ANOVA and Bonferroni test at a significance level of p<0.05. RESULTS: Mean shear bond strength data of the groups in MPa were; Variolink: 20.45+/-4.75, Variolink+Clearfil Protect Bond:29.32+/-2.37, RelyX ARC:18.82+/-3.19, RelyX ARC+Clearfil Protect Bond:25.58+/-4.05, Panavia F 2.0:17.11+/-2.98, Panavia F 2.0+Clearfil Protect Bond:24.40+/-7.46. Application of the antibacterial adhesive increased the shear bond strengths of all three dual-polymerizing systems to dentin (p=0.00). The surface analysis showed that most of the specimens showed the adhesive failure mode between the dentin and the composite luting agent interface. CONCLUSION: The antibacterial adhesive system Clearfil Protect Bond can be safely used to prevent the potential risk of complications resulting from bacterial activity regardless of affecting the bond strength of IPS Empress 2 restorations luted with the dual-polimerizing systems used in this study.


Assuntos
Antibacterianos/química , Resinas Compostas/química , Colagem Dentária , Adesivos Dentinários/química , Compostos de Piridínio/química , Cimentos de Resina/química , Bis-Fenol A-Glicidil Metacrilato/química , Porcelana Dentária/química , Análise do Estresse Dentário/instrumentação , Dentina/ultraestrutura , Humanos , Processamento de Imagem Assistida por Computador , Compostos de Lítio/química , Teste de Materiais , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície
17.
J Prosthet Dent ; 92(2): 116-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15295317

RESUMO

There has been an increase in the use of esthetic metal-free ceramic crowns in restoring endodontically treated teeth or teeth with severe coronal destruction. Tooth-colored dowels and cores are used to enhance the esthetic result. This report describes the treatment of a patient with bilateral maxillary supernumerary lateral incisors, a severe malocclusion, and maxillary anterior tooth discoloration. Treatment included heat-pressed, metal-free ceramic crowns supported by zirconia ceramic dowel-and-core foundations.


Assuntos
Cerâmica , Coroas , Materiais Dentários , Estética Dentária , Técnica para Retentor Intrarradicular/instrumentação , Zircônio , Adulto , Cerâmica/química , Materiais Dentários/química , Humanos , Incisivo/anormalidades , Masculino , Má Oclusão/terapia , Maxila , Descoloração de Dente/terapia , Dente não Vital/reabilitação , Dente Supranumerário/terapia , Zircônio/química
18.
Quintessence Int ; 35(3): 185-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15119675

RESUMO

The esthetic demands of patients have increased considerably during recent years. Due to this increasing interest in esthetics, as well as concerns about toxic and allergic reactions, the use of all-ceramic restorations has increased. One of the systems introduced for all-ceramic restorations is the IPS Empress system. This article examines one all-ceramic restoration system, IPS Empress, and presents patient cases in which all-ceramic crowns and fixed partial dentures have been utilized.


Assuntos
Silicatos de Alumínio , Coroas , Porcelana Dentária , Prótese Parcial Fixa , Adolescente , Adulto , Cimentação , Planejamento de Prótese Dentária , Humanos , Masculino , Ligas Metalo-Cerâmicas , Pessoa de Meia-Idade , Cimentos de Resina
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