Basic Operative Procedures: Amalgam and Composite Practice Questions
19 free Basic Operative Procedures: Amalgam and Composite practice questions for the CDA. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
What is the primary purpose of a matrix band during a Class II amalgam or composite restoration?
- A To protect the pulp
- B To provide a temporary interim restoration
- C To create proper contour and contact
- D To isolate the tooth from saliva
Correct answer: To create proper contour and contact
A matrix band forms the missing wall of the tooth and helps shape the final contour. It allows proper contact points to be restored.
Which instrument is used to condense amalgam into the prepared cavity?
- A Hollenback carver
- B Burnisher
- C Condenser
- D Explorer
Correct answer: Condenser
A condenser packs amalgam tightly to eliminate voids. Proper condensation strengthens the restoration.
Which step is required before placing composite material?
- A Trituration of the material
- B Etching and bonding
- C Carving and contouring
- D Burnishing the surface
Correct answer: Etching and bonding
Composite requires tooth surface etching and application of bonding agent. This ensures proper adhesion to enamel and dentin.
Which material is used to protect the pulp during deep cavity preparations?
- A Dental amalgam
- B Light-cured composite resin
- C Calcium hydroxide liner
- D Metal matrix band
Correct answer: Calcium hydroxide liner
Calcium hydroxide stimulates dentin formation and protects the pulp. It is placed under deep restorations.
What is the primary advantage of composite over amalgam?
- A Longer working time for placement
- B Superior esthetics and color match
- C Greater resistance to corrosion and tarnish
- D Higher compressive strength and load bearing
Correct answer: Superior esthetics and color match
Composite blends with tooth color and provides superior esthetics. It is preferred for visible anterior and posterior restorations.
Which instrument is used to shape and smooth composite before curing?
- A Composite placement instrument
- B Condenser
- C Amalgam carrier
- D Cleoid carver
Correct answer: Composite placement instrument
Composite instruments are coated or smooth to prevent sticking. They help shape the material before polymerization.
What occurs if composite is placed in increments that are too thick?
- A Composite placement instrument
- B Stainless steel condenser
- C Amalgam carrier
- D Cleoid-discoid carving instrument
Correct answer: Composite placement instrument
Thick increments prevent full curing and increase shrinkage. Layering improves bond strength and reduces stress.
What is the purpose of trituration in an amalgam procedure?
- A To remove all debris and contamination from the cavity
- B To harden the restorative material
- C To mix alloy and mercury for placement
- D To sterilize instruments before use
Correct answer: To mix alloy and mercury for placement
Trituration properly mixes mercury and alloy. Correct mixing ensures strength and reduces excess mercury.
Why is a rubber dam often recommended during composite procedures?
- A It prevents amalgam corrosion
- B Composite requires strict moisture control
- C It increases the strength of composite
- D It reduces postoperative sensitivity automatically
Correct answer: Composite requires strict moisture control
Composite bonding is highly sensitive to moisture. Isolation ensures optimal adhesion and restoration longevity.
Which bur is commonly used to refine the internal walls of a cavity preparation?
- A Football bur
- B Round bur
- C Straight fissure bur
- D Inverted cone bur
Correct answer: Inverted cone bur
Inverted cone burs create undercuts and refine cavity walls. They are frequently used in operative dentistry.
Which step occurs immediately after placing the matrix and wedge for a Class II composite?
- A Curing the composite
- B Etching the preparation
- C Polishing the restoration
- D Checking occlusion
Correct answer: Etching the preparation
Etching prepares the enamel and dentin for bonding. It must be done before applying adhesive and composite.
What is the purpose of using wedges in Class II restorations?
- A To increase retention of the restorative material
- B To prevent overhang and adapt the band
- C To speed up curing
- D To protect the pulp
Correct answer: To prevent overhang and adapt the band
Wedges secure the matrix band and prevent excess material at the gingival margin. This helps create a smooth contour.
Which instrument is used to carve anatomical detail in amalgam restorations?
- A Composite placement instrument
- B Hollenback carver
- C Amalgam carrier
- D High-speed bur
Correct answer: Hollenback carver
Carvers create grooves and anatomy in the amalgam before it sets. Proper carving restores natural contours and function.
What is a common cause of postoperative sensitivity in composite restorations?
- A Overcarving
- B Moisture contamination during bonding
- C Using a wedge
- D Excessive polishing
Correct answer: Moisture contamination during bonding
Moisture interferes with bonding and causes microleakage. Proper isolation is essential for composite success.
What should be done after finishing and polishing a composite restoration?
- A Apply fluoride varnish if indicated
- B Place a temporary filling
- C Remove all enamel
- D Place amalgam over the composite
Correct answer: Apply fluoride varnish if indicated
Fluoride helps remineralize adjacent enamel. It is beneficial after etching and bonding procedures.
Which material is used to fill the cavity in amalgam procedures?
- A Flowable resin
- B Powdered glass
- C Metal alloy mixed with mercury
- D Porcelain
Correct answer: Metal alloy mixed with mercury
Amalgam is composed of silver alloy and mercury. Proper mixing forms a durable restorative material.
Which curing light is most commonly used for polymerizing composite?
- A Heat lamp
- B LED curing light
- C Halogen oven
- D Laser curing system
Correct answer: LED curing light
LED lights are efficient and widely used for curing composite. They offer consistent output and reduced heat generation.
Which step should be done before polishing amalgam?
- A Allow the material to fully set, often after 24 hours
- B Cure with a blue light
- C Etch with phosphoric acid
- D Place a varnish layer
Correct answer: Allow the material to fully set, often after 24 hours
Amalgam requires time to harden fully before polishing. Early polishing can distort the surface.
Which factor improves composite bonding strength?
- A Placing composite in one large increment
- B Air-drying dentin completely
- C Using incremental layering
- D Skipping the bonding agent
Correct answer: Using incremental layering
Incremental layering reduces shrinkage stress and improves curing. It enhances overall bond strength and longevity.