Effect of Adhesive Resin Application on the Durability of Adhesion to CAD/CAM Glass-Ceramics after either Hydrofluoric Acid Etching or Self-etch Primer Application.

PURPOSE: To evaluate the effect of two surface conditioning methods, namely conventional hydrofluoric acid vs self-etching primer, and the application of adhesive on the bond strength of resin cement to CAD/CAM glass-ceramics. MATERIALS AND METHODS: Blocks (N = 96) (12 x 10 x 2.5 mm) were manufactured, 24 for each tested ceramic type: lithium silicate ceramic (LS), polymer-infiltrated ceramic (PIC), leucite-reinforced feldspathic ceramic (FD), and lithium-disilicate glass-ceramic (LD). For bond strength testing, 64 blocks were randomly divided into 16 groups (4 blocks per group) according to the following factors: ceramic: 4 levels; etching: 2 levels (HFS: hydrofluoric acid + silane or Monobond Etch & Prime [MEP]); and adhesive application: 2 levels, with (signified as A) and without. Then for each group, 15 resin cement cylinders (AllCem Dual, FGM) were built up. All specimens were subjected to thermocycling (10,000 cycles) and to shear bonding strength testing (SBS) (100 kgf, 0.5 mm/min). Mean shear stresses (MPa) were statistically analyzed by three-way ANOVA, Tukey's test, and Weibull analysis. RESULTS: The mean bond strength of group PIC-HFS-A (28.45 ± 7.6 MPa) was significantly higher than that of groups LS-HFS-A (12.11 ± 2.7MPa) and FDHFSA (20.86 ± 2.0MPa). Group PIC-HFS bond strength (25.02 ± 6.5 MPa) was significantly higher only when compared to group LS-HFS (15.82 ± 4.4 MPa). The LS group presented lower SBS compared to all other groups. No significant differences were found between HFS and MEP surface treatments. CONCLUSION: Surface treatment with MEP promotes adhesion similar to that of HFS. Additional application of adhesive after the surface treatments did not improve the bond strength.

Effect of different surface treatments on the micro tensile bond strength to dentin, biaxial flexural strength and roughness of CAD/CAM resin composite and polymer infiltrated ceramic.

OBJECTIVES: To evaluate the biaxial flexural strength (BFS), surface roughness (Ra) and micro tensile bond strength (µTBS) of two CAD/CAM materials after different surface treatments. MATERIALS AND METHODS: For µTBS, 64 human molars were used and 32 blocks of resin composite (RC-Lava Ultimate) and polymer-infiltrated ceramic (PIC -Vita Enamic). The blocks and teeth were distributed into 16 groups according to the factors "surface treatment" (HF: 10% hydrofluoric acid; APA: Al2O3 sandblasting; SC: silicate-Al2O3 sandblasting; MEP: Monobond Etch and Prime) and "thermal cycling" (TC). After cementation, the blocks were sectioned into 1 mm2 bars. Half of the specimens were thermocycled and submitted to µTBS test. For BFS, RC and PIC discs were made and distributed according to the surface treatments and after mechanical cycling, submitted to BFS test. Roughness, EDS, SEM, and Weibull analyses were also performed. Data were analyzed by (1 or 2-way) ANOVA and Tukey test (α = 0.05). RESULTS: For RC, SC and HF after TC showed significantly higher µTBS values. For PIC HF after TC showed higher µTBS than the other groups. For RC, the BFS was higher for MEP than Al2O3 and SC. For PIC, none of the surface treatments influenced BFS. CONCLUSION: The highest µTBS for RC was obtained with SC followed by silanization and for PIC, HF followed by silanization. The RC showed lower strength after Al2O3 blasting. For PIC all surface treatments resulted in similar BFS.

Effect of different surface treatments and multimode adhesive application on the Weibull characteristics, wettability, surface topography and adhesion to CAD/CAM lithium disilicate ceramic.

METHODOLOGY: This paper aims to evaluate the effect of different surface treatments on surface topography, wettability, and shear bond strength of resin cement to glass ceramic. For SBS test, 32 blocks (7x7x2 mm) of lithium disilicate were obtained and randomly divided into eight groups (four blocks per group) according to each surface treatment (HF 20 s, 60 s, 120 s + silanization/S or Scotch Bond Universal/ SBU) and the Monobond Etch & Prime - MEP application followed or not by SBU. On each treated surface ceramic block, up to four dual-curing resin cement cylinders were prepared and light-cured for 40s (N=120/n=15). The specimens were thermocycled (10,000 cycles, 5-55°C, 30 s) and the SBS test (50KgF, 0.5 mm/min) was performed. Furthermore, failure analysis, wettability, AFM, and SEM were carried out. SBS data (MPa) were analyzed using Student's t-test, two-way ANOVA, Tukey's test (5%) and Weibull's analysis. RESULTS: For HF experimental groups, two-way ANOVA presented the factors "etching time" and "bonding agent" as significant (p<0.05). After silane application, the HF groups presented similar bond strength. SBU application compromised the SBS, except for 120s etching time (HF120sS: 23.39ᵃ±6.48 MPa; HF120sSBU: 18.76ᵃ±8.81MPa). For MEP groups, SBU application did not significantly affect the results (p=0.41). The MEP group presented the highest Weibull modulus (4.08A) and they were statistically different exclusively from the HF20sSBU (0.58B). CONCLUSION: The HF 20s, 60s, 120 s followed by silane, promoted similar resin-bond strength to ceramic and the SBU application after HF or MEP did not increase the SBS.

Relationship between symptoms and imagenological signs of degenerative temporomandibular joint disorders using the Research Diagnostic Criteria for Temporomandibular Disorders and cone-beam computed tomography / Relação entre sintomas e sinais imagenológicos das disfunções degenerativas da articulação temporomandibular com o Research Diagnostic Criteria for Temporomandibular Disorders e a tomografia computadorizada de feixe cônico

ABSTRACT BAKGROUND AND OBJECTIVES: Arthralgia is a common complaint among patients with temporomandibular osteodegeneration, however, for the accurate diagnosis of osteodegeneration, it is suggested the adoption of imaging tests associated with standardized clinical diagnosis protocols. The objective of this study was to evaluate patients with degenerative changes in the temporomandibular joint previously visualized by cone beam computed tomography, relating these changes with the clinical diagnoses and symptoms of temporomandibular disorders, in order to conclude which of the degenerative changes develop more painful symptomatology. METHODS: A cross-sectional observational descriptive study. Thirty-eight patients who had previously done the cone beam computed tomography exam were evaluated. Subjects were grouped according to clinical diagnosis of temporomandibular joint changes using the Research Diagnostic Criteria for Temporomandibular Disorders questionnaire. The presence of pain was considered during lateral palpation; intra-articular palpation; excursive movements; and active mouth opening. RESULTS: Among the purely clinical diagnoses, only 10.5% were conclusive, classifying patients as suffering from osteoarthritis/osteoarthrosis. Painful joint symptoms were found in all groups, with no statistically significant difference. Similarly, the presence of degenerative disorders, including flattening, osteophytes, sclerosis, and erosion were found in similar proportions in all diagnosis groups. CONCLUSION: 89.5% of the degenerative changes were clinically underdiagnosed. There was a positive association between the presence of symptoms and the number of correct clinical diagnoses of osteoarthritis/osteoarthrosis obtained with the Research Diagnostic Criteria for Temporomandibular Disorders.

RESUMO JUSTIFICATIVA E OBJETIVOS: Entre os pacientes com osteodegeneração cortical temporomandibular, a artralgia é uma queixa comum, entretanto, para o diagnóstico preciso de osteodegeneração sugere-se a adoção de exames de imagem associados a protocolos de diagnóstico clínico padronizados. O objetivo deste estudo foi avaliar pacientes com alterações degenerativas da articulação temporomandibular previamente visualizados por tomografia computadorizada de feixe cônico, relacionando essas alterações com os diagnósticos e sintomas clínicos da disfunção temporomandibular, a fim de concluir quais das alterações degenerativas se associam ao sintoma álgico. MÉTODOS: Trata-se de um estudo observacional descritivo transversal. Foram avaliados 38 pacientes que já haviam realizado realizado a tomografia computadorizada de feixe cônico. Os indivíduos foram agrupados de acordo com o diagnóstico clínico de alterações na articulação temporomandibular, utilizando o questionário Research Diagnostic Criteria for Temporomandibular Disorders. A presença de dor foi considerada durante: palpação lateral; palpação intra-articular; movimentos excursivos; e abertura ativa da boca. RESULTADOS: Entre os diagnósticos puramente clínicos, apenas 10,5% foram conclusivos, classificando os pacientes como portadores de osteoartrite/osteoartrose. Sintomas articulares dolorosos foram encontrados em todos os grupos, sem diferença estatisticamente significante. Da mesma forma, a presença de distúrbios degenerativos, incluindo achatamento, osteófitos, esclerose e erosão, foi encontrada em proporções semelhantes em todos os grupos de diagnóstico. CONCLUSÃO: 89,5% das alterações degenerativas foram clinicamente subdiagnosticadas. Houve associação positiva entre a presença de sintomas e o número de diagnósticos clínicos corretos de osteoartrite/osteoartrose obtidos com o Research Diagnostic Criteria for Temporomandibular Disorders.

Effect of different surface treatments and multimode adhesive application on the Weibull characteristics, wettability, surface topography and adhesion to CAD/CAM lithium disilicate ceramic

Abstract This paper aims to evaluate the effect of different surface treatments on surface topography, wettability, and shear bond strength of resin cement to glass ceramic. Methodology: For SBS test, 32 blocks (7x7x2 mm) of lithium disilicate were obtained and randomly divided into eight groups (four blocks per group) according to each surface treatment (HF 20 s, 60 s, 120 s + silanization/S or Scotch Bond Universal/ SBU) and the Monobond Etch & Prime - MEP application followed or not by SBU. On each treated surface ceramic block, up to four dual-curing resin cement cylinders were prepared and light-cured for 40s (N=120/n=15). The specimens were thermocycled (10,000 cycles, 5-55°C, 30 s) and the SBS test (50KgF, 0.5 mm/min) was performed. Furthermore, failure analysis, wettability, AFM, and SEM were carried out. SBS data (MPa) were analyzed using Student's t-test, two-way ANOVA, Tukey's test (5%) and Weibull's analysis. Results: For HF experimental groups, two-way ANOVA presented the factors "etching time" and "bonding agent" as significant (p<0.05). After silane application, the HF groups presented similar bond strength. SBU application compromised the SBS, except for 120s etching time (HF120sS: 23.39ᵃ±6.48 MPa; HF120sSBU: 18.76ᵃ±8.81MPa). For MEP groups, SBU application did not significantly affect the results (p=0.41). The MEP group presented the highest Weibull modulus (4.08A) and they were statistically different exclusively from the HF20sSBU (0.58B). Conclusion: The HF 20s, 60s, 120 s followed by silane, promoted similar resin-bond strength to ceramic and the SBU application after HF or MEP did not increase the SBS.