Dimensional accuracy and detail reproduction of two hydrophilic vinyl polysiloxane impression materials tested under different conditions

Background and Objectives: A limitation of vinyl polysiloxane (VPS) impression materials is hydrophobicity, and manufacturers have added surfactants and labeled these new products as "hydrophilic." The purpose of this investigation was to evaluate and compare the dimensional accuracy and surface detail reproduction of two hydrophilic VPS impression materials under dry, moist, and wet conditions. Materials and Methods: Ten impressions were made under dry, moist, and wet conditions respectively, with monophase, and regular body VPS impression material using a stainless steel metal die similar to that described in American Dental Association (ADA) specification 19, with lines scribed on it. Dimensional accuracy was measured by comparing the average length of the middle horizontal line in each impression to the same line on the metal die, by using a measuring microscope. The surface detail was evaluated. A one-way analysis of variance and Student t-test were used to compare mean dimensional changes (α = 0.05). Results: Conditions (dry, moist, and wet) did not cause significant adverse effects on the dimensional accuracy of either material. The mean dimensional changes were 0.00084% (+0.00041%) for monophase and 0.00119% (+0.00033%) for regular body. Monophase material was satisfactory in detail reproduction 100% of the time in dry conditions, 90% in moist, and only 20% in wet conditions. The regular body showed 100% satisfactory impressions in dry, 80% in moist, and 10% in wet conditions. With the additional smooth surface evaluation, only under dry conditions impressions with clinically acceptable surface quality were produced. Conclusions: Dimensional changes for both materials were well within ADA standards of minimal shrinkage value of 0.5%

Association of edentulousness and removable prosthesis rehabilitation with severity of signs and symptoms of temporomandibular disorders

Context: There are very few studies concerning the role of denture status in temporomandibular disorders (TMDs) and those show conflicting results. Aim: To evaluate the association of edentulousness and removable prosthesis rehabilitation with severity of TMD signs and symptoms. Settings and Design: Data were collected from 2000 subjects reporting for dental treatment, above 30 years of age. Subjects and Methods: The subjects were interviewed with a questionnaire and clinically examined for TMD on basis of Helkimo's index. The number of existing teeth, wearing of removable dentures, need for denture repair, and age of dentures was recorded. Statistical Analysis: The association between the TMD findings and recorded variable outcomes was analyzed by means of Chi-square test. Results: Completely edentulous individuals associated more with TMD related findings in incidence and intensity than partially/fully dentate subjects. Complete denture wearers were more associated with TMD symptoms, limited mandibular mobility, muscle tenderness, and pain on mandibular movement. Partial denture wearers were more associated with severely impaired temporomandibular joint function and joint pain. Signs and symptoms of TMD were more prevalent and severe in patients who needed to get their dentures repaired, those wearing dentures more than 5-year-old, and in patients who had not got their dentures repaired during the past 5 years. Conclusions: Edentulousness, complete/partial denture wearing and poor condition of the dentures associate with greater incidence and intensity of TMD associated signs and symptoms

Alternative anterior esthetics: A case report

Due to the rise over the years in patient emphasis on better esthetic outcomes, veneering the metal base of a restoration with composite resin or porcelain is widely used in dentistry. For the preservation of the opposing natural dentition and the potential for repair, the use of composite veneering materials has been suggested because of their resilience, low abrasive properties, and superior repair potential. Composites are not as popular as porcelain, but they are still widely used to cover metal because of low cost and because the laboratorial procedures are faster and simpler

Shear Bond Strength of Composite Veneers and Acrylic Veneer Bonded to Ni–Cr Alloy: A Laboratory Study

A growing number of composite materials are being used as an alternative for veneering cast restorations. The objective of this investigation was to evaluate and compare the shear bond strength of UDMA based composite, restorative composite, and heat cure acrylic when veneered to Ni–Cr alloy and to evaluate the type of bond failure. Three different veneering materials were used: heat cure acrylic, UDMA based composite and a restorative composite. 10 samples were fabricated, each with heat cure acrylic and restorative composite and 20 samples were fabricated with UDMA based composite; thus, the total number of samples amounted to 40. All the samples were subject to shear bond stress fracture tests and observed for the type of bond failure. The greatest mean shear bond strength was recorded in relation to the UDMA based composite material when thermal conducting paste was used during the curing (10.51 MPa). The mean bond strength values of UDMA based composite without thermal conducting paste (8.92 MPa), heat cured acrylic veneering material (4.24 MPa) and restorative composite material (5.03 MPa) were significantly different from each other (p > 0.05). Samples veneered with heat cure acrylic veneering material and restorative composite material showed adhesive failure. Samples prepared with UDMA based composite veneering composite showed cohesive or predominantly cohesive failure. UDMA based composite veneering material when used with heat protection paste exceeds the shear bond strength requirement as suggested by Matsumura et al. (>10 MPa). A statistically significant association between the test groups and the type of failure was observed

Spleen tyrosine kinase/FMS-like tyrosine kinase-3 inhibition in relapsed/refractory B-cell lymphoma, including diffuse large B-cell lymphoma : updated data with mivavotinib (TAK-659/CB-659)

We report an updated analysis from a phase I study of the spleen tyrosine kinase (SYK) and FMS-like tyrosine kinase 3 inhibitor mivavotinib, presenting data for the overall cohort of lymphoma patients, and the subgroup of patients with diffuse large B-cell lymphoma (DLBCL; including an expanded cohort not included in the initial report). Patients with relapsed/refractory lymphoma for which no standard treatment was available received mivavotinib 60-120 mg once daily in 28-day cycles until disease progression/unacceptable toxicity. A total of 124 patients with lymphoma, including 89 with DLBCL, were enrolled. Overall response rates (ORR) in response-evaluable patients were 45% (43/95) and 38% (26/69), respectively. Median duration of response was 28.1 months overall and not reached in DLBCL responders. In subgroups with DLBCL of germinal center B-cell (GCB) and non-GCB origin, ORR was 28% (11/40) and 58% (7/12), respectively. Median progression free survival was 2.0 and 1.6 months in the lymphoma and DLBCL cohorts, respectively. Grade ≥3 treatment-emergent adverse events occurred in 96% of all lymphoma patients, many of which were limited to asymptomatic laboratory abnormalities; the most common were increased amylase (29%), neutropenia (27%), and hypophosphatemia (26%). These findings support SYK as a potential therapeutic target for the treatment of patients with B-cell lymphomas, including DLBCL. Trial registration: ClinicalTrials.gov number: NCT0200093