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1.
Oper Dent ; 49(3): 253-261, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38632860

RESUMO

OBJECTIVE: The objective of this study was to compare the efficacy of Biosilicate and Duraphat in the treatment of dentin hypersensitivity (DH). METHODS AND MATERIALS: This clinical trial was conducted with young adults presenting DH. A visual analogue scale (VAS) was used to assess the level of pain, using volatile and tactile tests. Forty participants presenting two teeth with DH were included, and these teeth were divided into two groups according to the treatment: Biosilicate or Duraphat. Each product was randomly applied on one tooth per participant once a week for 4 weeks and evaluated every 15 days for 60 days after the last application. RESULTS: The mean and standard deviation (SD) of VAS values for the initial volatile sensitivity evaluation were 6.18 (1.99) and 6.08 (1.98) for the Biosilicate and Duraphat groups, respectively, and at the fourth week 0.48 (1.5) and 0.83 (1.58). After 60 days, the volatile sensitivity showed the following values: 0.63 (1.19) for Biosilicate and 1.03 (1.07) for Duraphat. The intragroup comparison showed a significant reduction of mean VAS values for DH-related pain assessed by volatile testing for both groups (p<0.001), and the assessment at the 60-day follow-up showed mean values statistically similar to those obtained at the end of treatment. Initial tactile sensitivity observed was 1.48 (2.39) for the Biosilicate and 1.4 (2.2) for the Duraphat group and at the 60-day follow-up 0.23 (0.73) and 0.15 (0.36), respectively, with significant statistical difference (p<0.002). When the reduction in tactile and volatile sensitivities between both groups was compared, no statistically significant difference was observed. CONCLUSION: This study indicated that both products were able to promote an important reduction in dentin hypersensitivity with similar results within a 60-day follow-up.


Assuntos
Cerâmica , Sensibilidade da Dentina , Fluoretos Tópicos , Humanos , Sensibilidade da Dentina/tratamento farmacológico , Feminino , Masculino , Cerâmica/uso terapêutico , Adulto Jovem , Adulto , Fluoretos Tópicos/uso terapêutico , Fluoretos Tópicos/administração & dosagem , Medição da Dor , Resultado do Tratamento , Dessensibilizantes Dentinários/uso terapêutico
2.
J Prosthodont ; 33(4): 389-395, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37201944

RESUMO

PURPOSE: This study evaluated the fatigue failure load (FFL) and the number of cycles for fatigue failure (CFF) of traditional (porcelain layer up) and reversed (zirconia layer up) designs of porcelain-veneered zirconia samples prepared with heat-pressing or file-splitting techniques. MATERIALS AND METHODS: Zirconia discs were prepared and veneered with heat-pressed or machined feldspathic ceramic. The bilayer discs were bonded onto a dentin-analog according to the bilayer technique and sample design: traditional heat-pressing (T-HP), reversed heat-pressing (R-HP), traditional file-splitting with fusion ceramic (T-FC), reversed file-splitting with fusion ceramic R-FC), traditional file-splitting with resin cement (T-RC), and reversed file-splitting with resin cement (R-RC). The fatigue tests were performed using the stepwise approach at 20 Hz, 10,000 cycles/step, step-size of 200 N starting at 600 N, and proceeding until failure detection or up to 2600 N if enduring. The failure modes (from radial and/or cone cracks) were analyzed in a stereomicroscope. RESULTS: The reversed design decreased the FFL and CFF of bilayers prepared with heat-pressing and file-splitting with fusion ceramic. The T-HP and T-FC reached the highest results, which were statistically similar between them. The bilayers prepared by the file-splitting with resin cement (T-RC and R-RC) were similar to the R-FC and R-HP groups regarding FFL and CFF. Almost all reverse layering samples failed by radial cracks. CONCLUSIONS: The reverse layering design did not improve the fatigue behavior of porcelain veneered zirconia samples. The three bilayer techniques behaved similarly when used in the reversed design.


Assuntos
Cerâmica , Porcelana Dentária , Cerâmica/uso terapêutico , Cerâmica/química , Porcelana Dentária/química , Coroas , Cimentos de Resina , Teste de Materiais , Propriedades de Superfície , Análise do Estresse Dentário , Zircônio/química , Falha de Restauração Dentária
3.
Eur J Prosthodont Restor Dent ; 31(4): 346-357, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37382351

RESUMO

PURPOSE: This study evaluated the effect of coating traditional and translucent Y-TZP with an industrial nanometric colloidal silica or glaze before or after sintering on the adhesion of zirconia with various ytrria concentration. MATERIALS AND METHODS: Specimens of Y-TZP with 3% and 5% yttria were subdivided into 5 groups (n=10), according to the coating applied and moment of application (before or after Y-TZP sintering): Control (no coating), Colloidal Silica/Sintering, Sintering/Colloidal Silica, Glaze/Sintering, Sintering/ Glaze. Lithium disilicate (LD) was used as positive control. Except for Y-TZP controls, groups were conditioned with silane before cementation with a self-adhesive resin cement. After 24 hours, the shear bond strength and failure analysis were performed. Also, analysis of specimens' surface was accomplished with SEM-EDX. Kruskal-Wallis and Dunn tests were applied to analyze differences between groups (p⟨0.05). RESULTS: Overall, the worst and best values of shear bond strength test were control and glaze after sintering groups. Different morphological and chemical aspects were observed in SEM-EDX analysis. CONCLUSIONS: Coating Y-TZP with colloidal silica showed unsatisfactory results. In 3Y-TZP, the surface treatment associated with the best adhesion values was the application of glaze after zirconia sintering. However, in 5Y-TZP, glaze application can be performed before or after the zirconia sintering to optimize clinical steps.


Assuntos
Colagem Dentária , Dióxido de Silício , Propriedades de Superfície , Dióxido de Silício/química , Cimentação , Zircônio/química , Cimentos de Resina , Teste de Materiais , Ítrio/química , Ítrio/uso terapêutico , Colagem Dentária/métodos , Cerâmica/uso terapêutico
4.
Oper Dent ; 48(4): 358-363, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37079913

RESUMO

OBJECTIVE: This case report describes a minimally invasive approach with tooth whitening and partial ceramic veneers in the esthetic zone with a 5-year follow-up. CLINICAL CONSIDERATIONS: The patient was initially concerned about the tooth color and previous direct resin composite restorations that chipped on the incisal edges of both maxillary central incisors. Tooth whitening and partial veneers for both central incisors were recommended after clinical evaluation. Two sessions of in-office tooth whitening, first with 35% hydrogen peroxide and later with 10% carbamide peroxide from first premolar to first premolar, were provided. Minimal tooth preparation that only removed the fractured composite restorations was performed followed by placement of feldspathic porcelain ultrathin partial ceramic veneers for both central incisors. We emphasize the benefits of minimal tooth preparation paired with partial ceramic veneers and the importance of masking discolored tooth structure with such thin veneers, including potential tooth whitening. CONCLUSIONS: Overall, we demonstrate a well-planned and executed restorative procedure combining tooth whitening and ultrathin partial ceramic veneers to achieve desired results in the esthetic zone that remained successful for five years.


Assuntos
Porcelana Dentária , Clareamento Dental , Humanos , Porcelana Dentária/uso terapêutico , Porcelana Dentária/química , Estética Dentária , Cerâmica/uso terapêutico , Resinas Compostas/química , Facetas Dentárias
5.
J Prosthet Dent ; 129(6): 931-937, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34482967

RESUMO

STATEMENT OF PROBLEM: The lack of standardization regarding the loading piston material used in fatigue tests could limit the interpretation of study findings. PURPOSE: The purpose of this in vitro study was to evaluate the effect of the piston material on the fatigue behavior of a lithium disilicate glass-ceramic. MATERIAL AND METHODS: Plate-shaped, 1.2-mm-thick, lithium disilicate glass-ceramic specimens were cemented onto a dentin analog substrate with resin cement. The specimens were divided into 4 groups according to the piston material used in the fatigue test (n=30): metal, glass fiber-reinforced epoxy resin, ceramic, and human tooth. The fatigue test was performed in a mechanical cycling machine by using the boundary technique at 2 Hz in distilled water at 37 °C. The fatigue data were analyzed by using the Weibull distribution and a lifetime-inverse power law relationship. Failures were evaluated with fractography and transillumination. RESULTS: The Weibull modulus (ß) was similar among groups. The exponent of crack growth (n) was significantly greater for glass fiber-reinforced epoxy resin and tooth groups than for metal and ceramic; therefore, the probability of failure (Pf) of glass-ceramic specimens loaded by resin and tooth pistons depended more on load amplitude. Specimens tested with tooth showed the highest value of K (characteristic lifetime), which is an indication of greater survival. Radial crack was the only failure mode observed for all experimental groups. CONCLUSIONS: The piston material influenced the fatigue survival of the lithium disilicate glass-ceramic. The glass fiber-reinforced epoxy resin piston closely simulated the fatigue behavior induced by the human tooth on the evaluated glass-ceramic.


Assuntos
Implantes Dentários , Resinas Epóxi , Humanos , Cerâmica/uso terapêutico , Porcelana Dentária , Cimentos de Resina , Teste de Materiais , Análise do Estresse Dentário , Propriedades de Superfície
6.
Prim Dent J ; 11(4): 78-85, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36533364

RESUMO

The influence of different surface treatments and ageing on the shear bond strength (SBS) of computer-aided design/computer-aided manufacturing (CAD/CAM) materials is still contentious. Therefore, this study evaluated the effect of surface treatments and ageing on the SBS of resin cement to polymer-infiltrated ceramic network (PICN) and zirconia-reinforced lithium silicate (ZLS) CAD/CAM materials. Specimens of PICN (n=10) and ZLS (n=10) were submitted to four surface treatment groups: 1) 5% hydrofluoric acid etching (HF) + silanisation (SI); 2) Air abrasion (AB)+HF+SI; 3) HF + universal adhesive (UA); 4) AB+HF+SI+UA. The treated specimens were bonded with resin cement cylinders and tested in SBS after 24 h and one year of water storage. Data were assessed by "analysis of variance" (ANOVA) and Tukey test (α=0.05) and failure modes were classified. No significant differences were observed among treatments at each evaluation time (p>0.05). SBS decreased after one year of storage, except for PICN treated with HF+UA (p=0.068). Air-abraded groups displayed a lower SBS reduction for ZLS. PICN and ZLS exhibited predominantly adhesive and mixed failures, but at one year, PICN cohesive failures increased. In conclusion, HF+UA is an effective surface treatment for PICN, while the combination AB+HF+SI+UA was more appropriate for ZLS. The water storage for one year reduced the SBS for most groups.


Assuntos
Colagem Dentária , Cimentos de Resina , Humanos , Cimentos de Resina/uso terapêutico , Abrasão Dental por Ar , Teste de Materiais , Propriedades de Superfície , Cerâmica/uso terapêutico , Cerâmica/química , Desenho Assistido por Computador , Água , Porcelana Dentária/química
7.
J Prosthet Dent ; 128(5): 1084.e1-1084.e8, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36460426

RESUMO

STATEMENT OF PROBLEM: When glass-ceramics are treated with hydrofluoric acid (HF), not only the area of application is affected but also other surfaces. Information regarding the correlation of the dissolution caused by HF and the flexural strength of the ceramic is lacking. PURPOSE: The purpose of this in vitro study was to investigate the effect of HF etching protocols on the flexural strength of 2 glass-ceramics, the correlation of their flexural strength with the internal and lateral dissolution, and the differences in Weibull characteristics concerning the etching protocols. MATERIAL AND METHODS: Specimens (4×12×0.3mm) of leucite-reinforced glass-ceramic-LEU (IPS Empress) and of lithium disilicate-reinforced glass-ceramic-LD (IPS e.max) were prepared. The specimens were divided into 5 groups (n=12) according to etching protocol: control-untreated; hydrofluoric acid (HF) 5% for 20 seconds (HF5%20s); HF5%60s; HF10%20s; and HF10%60s. Flexural strength was evaluated through 3-point bend testing. The fractured specimens were submitted to a morphological and metrical analysis of each pattern (LEU I-IV, LD I-III) on the lateral surface (LS) and of the dissolution areas (µm2) on the internal surface (IS) using a scanning electron microscopy (SEM) and a software program (FIJI). Flexural strength (MPa) values were analyzed by 1-way ANOVA, Bonferroni test, and Weibull and the correlation between flexural strength and dissolution by Pearson correlation coefficient (α=.05). RESULTS: ANOVA revealed that the HF etching protocol was significant (P<.001) for LEU ceramic. When HF10%60s was applied, LEU showed Weibull characteristic strength (σθ) values lower than those of the other protocols. LD showed no difference in σθ and reliability (m) among the groups. The internal dissolution areas concerning LEU had a significant high negative correlation with the flexural strength (r=-0.6; P<.001). LEU-IV on the LS was the only pattern to show a significant decrease in flexural strength (r=-0.3, P<.05). CONCLUSIONS: Special care should be taken when applying hydrofluoric acid on glass-ceramic restorations. Protocols with higher hydrofluoric acid concentrations and longer application times were more related to greater internal areas of dissolution which reduced the flexural strength of leucite ceramics.


Assuntos
Resistência à Flexão , Ácido Fluorídrico , Reprodutibilidade dos Testes , Solubilidade , Cerâmica/uso terapêutico
8.
Oper Dent ; 47(6): E264-E272, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36322401

RESUMO

OBJECTIVES: To evaluate the bond strength of a resin luting agent to a lithium disilicate glass-ceramic after the use of different fit-checking materials and cleaning protocols. METHODS AND MATERIALS: Two hundred and forty-two (242) ceramic specimens were etched with 5% hydrofluoric acid for 20 seconds and distributed into 22 groups (n=10), in total. Four (4) groups were created based on fit-checking material and that had no following cleaning protocol: no fit-checking material used (control group); articulating paper; articulating spray; and fit-checker liquid. For each fit-checking material (3), 6 cleaning protocols were tested creating an additional 18 groups (n=10): air/water spray; 70% alcohol (ethanol); acetone; 35% phosphoric acid; 5% hydrofluoric acid; and a commercially available cleaning paste (Ivoclean, Ivoclar Vivadent). Silane and bonding resin were applied to all ceramic surfaces. Resin luting agent cylinders (1 mm in diameter) were created using silicone matrices, light-cured, and specimens were stored in deionized water at 37°C for 24 hours. Microshear bond strength test (µSBS) was performed on a universal testing machine (DL 500, EMIC) at a crosshead speed of 1 mm/min until failure. Results were statistically analyzed using ANOVA and Tukey's test (α=0.05). RESULTS: Articulating paper and fit-checker liquid, when not properly removed, negatively affected the bond strength (p<0.05). None of the tested cleaning protocols were effective for articulating paper (p<0.05). There was no significant difference in bond strength after the cleaning protocols between articulating spray and fit-checker liquid when compared to the control group (no contamination) (p>0.05). CONCLUSION: The cleaning protocols tested can effectively restore the bond strength of resin luting agents to lithium disilicate ceramics that were exposed to articulating spray or fit-checker liquid. The use of articulating paper is not recommended for fit-checking indirect lithium disilicate restorations.


Assuntos
Colagem Dentária , Ácido Fluorídrico , Ácido Fluorídrico/química , Colagem Dentária/métodos , Análise do Estresse Dentário , Teste de Materiais , Porcelana Dentária/uso terapêutico , Porcelana Dentária/química , Cerâmica/uso terapêutico , Cerâmica/química , Cimentos de Resina/uso terapêutico , Cimentos de Resina/química , Silanos/química , Água/química , Propriedades de Superfície
9.
J Prosthet Dent ; 128(3): 496.e1-496.e8, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35985853

RESUMO

STATEMENT OF PROBLEM: Information regarding the masking ability of ceramic crowns over different implant abutment materials is scarce. PURPOSE: The purpose of this in vitro study was to evaluate the masking ability of different monolithic or bilayer ceramic materials with different thicknesses over substrates indicated for implant restorations by using opaque and translucent evaluation pastes. MATERIAL AND METHODS: Disk-shaped specimens, shade A1 (VITA Classic; Ø10×1.5 to 2.5 mm), of different ceramics (a bilayer system [yttria-stabilized zirconia infrastructure+porcelain veneer: Zir+Pc] and monolithic systems [lithium disilicate under low, medium, or high translucency: LtLD, MtLD, or HtLD, respectively, and a high-translucent yttria-stabilized zirconia: HtZir]) were made (n=4). The color difference (ΔE00) was assessed by using the CIEDE2000 formula and considering the different ceramic systems over 5 implant abutment materials (A1 shade Zir [Zir A1]; white Zir [White Zir]; A1 low-translucency lithium disilicate [LD]; polyetheretherketone [PEEK]; and titanium [Ti]) when using 2 different evaluation pastes (translucent or opaque). The control comparison was the restorative material positioned over the Zir A1 substrate with a translucent evaluation paste. Statistical analysis was made by using a 2-way ANOVA and Tukey post hoc tests (α=.05) for ΔE00 data considering the restorative material and luting agent factors as their association. Additionally, ΔE00 data were qualitatively analyzed considering the acceptability and perceptibility thresholds. The translucency parameter (TP00) of each restorative material was evaluated, and data were submitted to 1-way ANOVA and Tukey post hoc tests (α=.05). RESULTS: The most predictable masking ability was seen with Zir+Pc regardless of the evaluation paste used. Nevertheless, under 1.5-mm thickness, Zir+Pc did not adequately mask Ti (ΔE00>1.77). Most monolithic ceramics did not mask discolored substrates (PEEK or Ti, ΔE00>1.77). The exception was HtZir, which presented acceptable masking ability over PEEK at 2.5-mm thickness with both evaluation pastes (ΔE00<1.77). Regardless of the restorative material thickness, Zir+Pc showed the lowest (P<.05) TP00 values (TP00=3.45 at 1.5-mm thickness; TP00=2.00 at 2.5-mm thickness), and HtLD presented the highest (P<.05, TP00=23.50 at 1.5-mm thickness; TP00=13.36 at 2.5-mm thickness). HtZir showed similar TP00 to MtLD at 1.5-mm thickness and similar TP00 to Zir+Pc when used at 2.5-mm thickness (P>.05). CONCLUSIONS: Monolithic ceramics should be used with caution over discolored implant abutments. Bilayer systems (Zir+Pc) were the most predictable approach to adequately masking discolored substrates such as PEEK or Ti. An increased restoration thickness provided higher masking ability for all restorative materials tested.


Assuntos
Implantes Dentários , Porcelana Dentária , Benzofenonas , Cerâmica/uso terapêutico , Cor , Coroas , Cimentos Dentários , Materiais Dentários , Teste de Materiais , Polímeros , Propriedades de Superfície , Titânio , Ítrio , Zircônio
10.
Eur Spine J ; 31(9): 2262-2269, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35723748

RESUMO

PURPOSE OF THE STUDY: The objective of this prospective, parallel, randomized, single-center study is to evaluate the clinical success of a commercial ceramic bone graft substitute (CBGS) for autograft in eXtreme Lateral Interbody Fusion (XLIF) procedures. Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Cristiano Magalhães], Last name [Menezes]. Author 2 Given name: [Gabriel Carvalho], Last name [Lacerda]. Author 5 Given name: [Erica Godinho], Last name [Menezes]. Also, kindly confirm the details in the metadata are correct.yes METHODS: Forty-five adult subjects were consecutively enrolled and randomized into a single-level XLIF procedure using either CBGS or iliac crest bone graft autograft (30 and 15 subjects, respectively). The primary outcome was fusion rate at 12, 18, and 24 months. Secondary outcomes were pain and disability measured by HRQOL questionnaires. Kindly check and confirm whether the corresponding author and his corresponding affiliations is correctly identified.yes RESULTS: The fusion rates for both CBGS and autograft groups at the 24-month follow-up were 96.4% and 100%, respectively. For the CBGS group, mean ODI, mean back pain, and mean worst leg pain significantly improved at the 24-month follow-up by 76.7% (39.9-9.3), 77.6% (7.3-1.6), and 81.3% (5.1-1.0), respectively. For the autograft group, mean ODI, mean back pain, and mean worst leg pain significantly improved during the same time period by 77.1% (35.9-8.2), 75.6% (6.1-1.5), and 86.0% (6.6-0.9), respectively (all time points between groups, p < 0.05). CONCLUSION: The results of this prospective, randomized study support the use of CBGS as a standalone bone graft substitute for autograft in single-level XLIF surgery. The clinical performance and safety outcomes reported here are consistent with published evidence on CBGS. Improvements in patient-reported back pain, leg pain, and disability outcomes were comparable between the CBGS and autograft groups.


Assuntos
Substitutos Ósseos , Fusão Vertebral , Adulto , Autoenxertos , Substitutos Ósseos/uso terapêutico , Transplante Ósseo/métodos , Cerâmica/uso terapêutico , Humanos , Vértebras Lombares/cirurgia , Dor , Estudos Prospectivos , Fusão Vertebral/métodos , Resultado do Tratamento
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