MDS PREP
What is the typical setting time for a high strength dental stone?
1) Less than 10 minutes.
2) 10-30 minutes.
3) 30-60 minutes.
4) More than 60 minutes.
High strength dental stones typically have a setting time of 30-60 minutes, which allows for sufficient working time while providing enhanced mechanical properties.
What is the primary function of a luting agent in the context of dental restorations?
1) To bond the restoration to the tooth
2) To provide a protective barrier against bacteria
3) To insulate the tooth from thermal changes
4) To fill in gaps caused by tooth decay
A luting agent's primary function is to bond the restoration to the tooth and enhance its retention.
What is the effect of trituration time on the dimensional change of spherical amalgam alloys?
1) It increases with increased trituration time.
2) It decreases with increased trituration time.
3) It is not affected by trituration time.
4) It is greatest at normal trituration time.
Compressive and tensile strengths of spherical alloys are greatest at normal trituration time.
What type of dental cement is used in cases of rampant caries and unhygienic oral conditions?
1) Zinc polyacrylate
2) Calcium sulfate
3) Zinc oxide-eugenol
4) Calcium hydroxide
Calcium hydroxide is used in cases of rampant caries and unhygienic oral conditions due to its antibacterial and tissue-dissolving properties.
What is the typical force applied with a condenser during restorative procedures?
1) 0.04-0.4 µm
2) 1-5 µm
3) 3.75 pounds
4) 8.43 pounds
The typical force applied with a condenser during restorative procedures is 3.75 pounds for a 0.5 mm diameter nib, 8.43 pounds for a 0.75 mm diameter, and 15 pounds for a 1 mm diameter nib. The force is applied parallel to the long axis of the instrument shaft.
What is the maximum allowable dimensional change for amalgams according to ANSI/ADA Specification No. 1?
1) Not more than 10 µm/cm.
2) Not more than 20 µm/cm.
3) Not more than 30 µm/cm.
4) Not more than 40 µm/cm.
The specification requires that amalgam neither contract nor expand more than 20 µm/cm.
What are the typical operating speeds for low-, medium-, and high-speed amalgamators?
1) 3000 to 3200 cpm for low-speed, 3500 to 3700 cpm for medium-speed, and 4000 to 4400 cpm for high-speed.
2) 3200 to 3400 cpm for low-speed, 3700 to 3800 cpm for medium-speed, and 4000 to 4400 cpm for high-speed.
3) 3000 to 3200 cpm for medium-speed, 3500 to 3700 cpm for high-speed, and 4000 to 4400 cpm for low-speed.
4) 3200 cpm for low-speed, 3700 cpm for medium-speed, and 4400 cpm for high-speed.
Low-speed amalgamators operate at 3200 to 3400 cpm, medium-speed at 3700 to 3800 cpm, and high-speed at 4000 to 4400 cpm.
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.