Preventive Materials and Techniques Practice Questions
20 free Preventive Materials and Techniques 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 fluoride varnish in preventive dentistry?
- A To whiten the enamel surface cosmetically
- B To strengthen enamel and reduce caries
- C To remove plaque and calculus deposits
- D To polish existing composite restorations
Correct answer: To strengthen enamel and reduce caries
Fluoride varnish enhances remineralization and strengthens enamel. It is especially effective for high-risk patients.
Which type of professional fluoride treatment is most commonly used for young children?
- A Fluoride gel in trays
- B Fluoride foam
- C Fluoride varnish
- D Silver diamine fluoride
Correct answer: Fluoride varnish
Fluoride varnish adheres well and reduces ingestion risk. It is safe and effective for pediatric patients.
What is the main purpose of pit and fissure sealants?
- A To smooth exposed root surfaces after scaling
- B To prevent decay in deep grooves of molars
- C To strengthen and support periodontal ligaments
- D To protect crowns and fixed bridges from wear
Correct answer: To prevent decay in deep grooves of molars
Sealants block bacteria and food from entering pits and fissures. They are highly effective in preventing occlusal caries.
Which polishing agent is most appropriate for patients with composite restorations?
- A Coarse pumice
- B Non-abrasive polishing paste
- C Tin oxide
- D Prophy jet powder
Correct answer: Non-abrasive polishing paste
Non-abrasive pastes prevent scratching of composite surfaces. This maintains esthetics and longevity.
What is the purpose of using disclosing agents during preventive appointments?
- A To measure periodontal pockets
- B To stain plaque for patient education
- C To clean stain from enamel
- D To harden enamel
Correct answer: To stain plaque for patient education
Disclosing solutions highlight areas of plaque accumulation. They are useful for instruction and improving oral hygiene habits.
Which ingredient in toothpaste helps reduce tooth sensitivity?
- A Stannous fluoride
- B Calcium hydroxide
- C Potassium nitrate
- D Carbamide peroxide
Correct answer: Potassium nitrate
Potassium nitrate reduces nerve excitability. It is commonly used to treat dentinal hypersensitivity.
Which preventive material is used to arrest active caries in high-risk patients?
- A Silver diamine fluoride (SDF)
- B Zinc oxide eugenol
- C Glass ionomer cement
- D Sealant resin
Correct answer: Silver diamine fluoride (SDF)
SDF has strong antimicrobial properties and stops the progression of caries. It is often used when traditional treatment is not possible.
Which instrument is most commonly used to polish teeth during a prophylaxis?
- A High-speed handpiece
- B Ultrasonic scaler
- C Slow-speed handpiece with prophy cup
- D Sickle scaler
Correct answer: Slow-speed handpiece with prophy cup
A slow-speed handpiece with a rubber prophy cup is standard for polishing. It effectively removes stains and soft deposits.
What is the function of a desensitizing agent applied to exposed dentin?
- A To improve bonding
- B To occlude dentinal tubules
- C To disinfect the tooth
- D To stimulate enamel growth
Correct answer: To occlude dentinal tubules
Desensitizing agents block tubules that transmit fluid movement causing sensitivity. This reduces patient discomfort.
Which preventive technique is essential for managing patients with high caries risk?
- A Annual radiographs only
- B Dietary counseling and fluoride therapy
- C Extraction of primary teeth
- D Daily rinsing with water
Correct answer: Dietary counseling and fluoride therapy
Diet counseling reduces sugar intake while fluoride strengthens enamel. Together they effectively reduce caries activity.
What is the purpose of air-polishing systems during prophylaxis?
- A To remove deep caries from posterior molar teeth surfaces
- B To remove plaque and extrinsic stains via powder spray
- C To shape and finish restorative composite materials neatly
- D To clean interdental spaces exclusively and nowhere else
Correct answer: To remove plaque and extrinsic stains via powder spray
Air polishing gently removes stains using abrasive powders. It is often more comfortable than mechanical polishing.
Which fluoride concentration is typically found in over-the-counter toothpastes?
- A 0.02%
- B 0.24%
- C 1.1%
- D 5%
Correct answer: 0.24%
Most OTC toothpastes contain about 0.24% sodium fluoride (1100 ppm). This level provides daily preventive benefit.
Which material slowly releases fluoride over time to help prevent recurrent decay?
- A Composite resin
- B Amalgam
- C Glass ionomer cement
- D Gold alloy
Correct answer: Glass ionomer cement
Glass ionomer cements release fluoride, offering long-term caries prevention. They are useful near the gingival margin.
Which technique improves plaque removal for patients with limited dexterity?
- A Manual flossing only
- B Non-fluoride toothpaste
- C Powered toothbrush
- D Avoiding brushing for sensitivity
Correct answer: Powered toothbrush
Powered toothbrushes provide consistent motion and improve cleaning efficiency. They are ideal for patients with dexterity challenges.
What is the purpose of remineralization therapy?
- A To extract decayed teeth
- B To reverse early enamel demineralization
- C To harden calculus deposits
- D To whiten discolored enamel
Correct answer: To reverse early enamel demineralization
Fluoride and calcium-phosphate products help rebuild weakened enamel. This prevents progression to cavities.
Why are sealants recommended primarily for children and adolescents?
- A Their teeth are naturally far easier to clean and polish
- B Pits and fissures are most susceptible after eruption
- C Sealants are known to bond far more reliably to primary dentition
- D Adult permanent teeth simply cannot be effectively sealed
Correct answer: Pits and fissures are most susceptible after eruption
Newly erupted molars have deep grooves that are highly prone to caries. Sealants protect these vulnerable surfaces.
Which step must occur before applying a resin-based sealant?
- A Etching the enamel
- B Applying fluoride gel
- C Using coarse pumice
- D Checking occlusion
Correct answer: Etching the enamel
Etching creates a roughened surface for micromechanical retention. This is essential for resin sealant bonding.
Which preventive measure helps reduce gingivitis?
- A Sealant placement
- B Routine mechanical plaque removal
- C Fluoride varnish
- D Air polishing only
Correct answer: Routine mechanical plaque removal
Brushing and flossing remove plaque, the primary cause of gingivitis. Regular hygiene appointments reinforce this.
Which material is used to help remineralize white spot lesions?
- A Calcium-phosphate products
- B Temporary cement
- C Alginate impression material
- D Sodium hypochlorite
Correct answer: Calcium-phosphate products
Calcium-phosphate systems provide minerals needed to repair early enamel lesions. They work synergistically with fluoride.
Which preventive technique is useful for patients with orthodontic appliances?
- A Use of fluoride mouthrinse
- B Avoid brushing around brackets
- C Using only a soft diet
- D Skipping regular hygiene visits
Correct answer: Use of fluoride mouthrinse
Fluoride rinses help protect enamel around brackets where plaque accumulates. This reduces risk of white spot lesions.