EFDA Dental Materials & Equipment Maintenance 4

Question 1

Which curing light intensity is considered the minimum for adequate polymerization of composite resin?

Accepted Answer

400 mW/cm²

Answer

A minimum irradiance of 400 mW/cm² is generally required to achieve adequate polymerization depth and degree of conversion in composite resins.

Question 2

What is the function of a matrix band during a Class II composite restoration?

Accepted Answer

Provide a temporary wall to replace the missing proximal surface during condensation

Answer

A matrix band recreates the proximal wall of the tooth, allowing the composite to be condensed against it and achieving proper contour and contact.

Question 3

Which solvent is recommended to clean composite resin that has not yet been light-cured from instruments?

Accepted Answer

Alcohol (isopropyl)

Answer

Isopropyl alcohol effectively dissolves uncured composite resin from instruments without damaging them.

Question 4

When using an ultrasonic scaler, the water spray serves which critical function?

Accepted Answer

Cool the tip and lavage the surgical site to prevent thermal damage

Answer

The water coolant prevents heat buildup from ultrasonic vibration that could damage the pulp, and flushes debris from the subgingival area.

Question 5

What is a key reason why dental impression materials should be poured promptly after removal from the mouth?

Accepted Answer

Syneresis or imbibition can alter the dimensional accuracy of the impression

Answer

Alginate and hydrocolloid impressions undergo syneresis (shrinkage) or imbibition (expansion) if not poured immediately, causing dimensional inaccuracies in the resulting model.

(EFDA) Expanded Function Dental Auxiliary Practice Test

(EFDA) Expanded Function Dental Auxiliary Practice Test

EFDA Dental Materials & Equipment Maintenance 4