MDS PREP
What is the typical intensity range of a dental argon laser?
1) 1-10 mW.
2) 100-500 mW.
3) 500-1000 mW.
4) More than 1000 mW.
Dental argon lasers typically operate within the range of 100 to 500 mW, providing sufficient power for soft tissue procedures and some hard tissue interactions.
What is the primary difference between a glass ionomer and a resin-modified glass ionomer cement?
1) Setting time
2) Mechanism of bonding
3) Compressive strength
4) Fluoride release
The primary difference is the presence of resin in resin-modified glass ionomer, enhancing bonding and strength.
What is the general source of the substance used in irreversible hydrocolloid impression material?
1) Synthetic polymer
2) Plant resin
3) Brown seaweed
4) Petroleum by-product
The material is derived from the structural formula of anhydro-?-d-mannuronic acid, which is extracted from certain types of brown seaweed.
What is the role of camphorquinone in photocuring of resin composites?
1) It emits blue light for curing.
2) It absorbs blue light and initiates polymerization.
3) It enhances the color stability of the composite.
4) It is a filler material for increasing strength.
Camphorquinone is a photosensitizer that absorbs blue light and initiates the free radical polymerization of the resin when irradiated, leading to cross-linking and setting of the composite.
What is the primary mechanism of bonding for resin-modified glass ionomer cements?
1) Micromechanical retention
2) Chemical bonding to tooth structure
3) Ionic bonding
4) Physical adsorption
Resin-modified glass ionomer cements bond through micromechanical retention and chemical bonding.
What is the maximum allowable creep for a 1-day-old amalgam specimen under a 36 MPa stress at 37°C according to ANSI/ADA Specification No. 1 (ISO 24234)?
1) 0.5%
2) 1%
3) 2%
4) 3%
The maximum allowable creep is 1% for amalgam quality according to the specification.
What are Compomers more correctly termed?
1) Methacryloxy decyl pyridinium bromide-modified composite resins
2) Polyacid-modified composite resins
3) Polymethacrylate-based composite resins
4) Glass ionomer-modified composite resins
Compomers are more correctly termed Polyacrylic acid Modified Composite Resins (PMCRs). They are a blend of glass ionomer and composite resin properties, making them user-friendly and suitable for certain restorative procedures.
What is the minimum compressive strength required for lining materials?
1) 1.0 MPa
2) 3.0 MPa
3) 5.0 MPa
4) 10 MPa
Lining materials must have a minimum compressive strength of 5 MPa to withstand the forces in the oral cavity.