Finishing and Polishing Restorations Practice Questions
21 free Finishing and Polishing Restorations 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 goal of the “finishing” step in restoration finishing and polishing procedures?
- A To bond the restoration permanently to the underlying tooth structure
- B To shape it, remove excess material and smooth margins
- C To apply a high-gloss shine to the restoration surface
- D To disinfect the restoration surface
Correct answer: To shape it, remove excess material and smooth margins
Finishing involves contouring the restoration, removing excess material and creating smooth margins and proper occlusal anatomy before polishing. It does not include bonding, gloss application, or disinfection.
What does the “polishing” step accomplish after finishing a restoration?
- A It restores the layer of natural enamel underneath the restoration
- B It creates a smooth, glossy surface that reduces roughness
- C It etches the restoration to improve adhesion
- D It applies fluoride to protect the restoration
Correct answer: It creates a smooth, glossy surface that reduces roughness
Polishing smooths microscopic irregularities and produces a lustrous, enamel-like surface that improves appearance and resists plaque accumulation.
Why is it critical to finish and polish composite restorations instead of leaving the surface as light-cured?
- A Because the light-cured surface is far too hard for comfortable chewing
- B Because the outer resin-rich layer is prone to stain and wear
- C Because polishing helps the composite bond more strongly to enamel
- D Because finishing stops polymerization
Correct answer: Because the outer resin-rich layer is prone to stain and wear
After curing, the outer resin-rich layer tends to attract stains and wear over time if left unpolished, so polishing improves stain resistance and longevity.
Which sequence best describes the standard order of steps for finishing and polishing a composite restoration?
- A Polishing, then finishing, then carving away excessive material, then a final check
- B Gross reduction, contouring, fine finishing, polishing
- C Curing, polishing, checking occlusion, finishing
- D Etching, finishing, polishing, bonding
Correct answer: Gross reduction, contouring, fine finishing, polishing
The correct workflow for restorations is gross removal of excess, contouring to correct shape, fine finishing to smooth margins, followed by polishing for surface luster.
Which type of bur is most commonly recommended for the gross finishing step of composite restorations?
- A Multi-fluted tungsten carbide finishing burs
- B Fine diamond burs used exclusively for this initial step
- C Prophy cup with polishing paste
- D Scaler
Correct answer: Multi-fluted tungsten carbide finishing burs
Tungsten carbide burs with multiple flutes are standard for gross finishing and contouring composite restorations before finer finishing and polishing.
What is a key risk of performing polishing at high speed without water cooling during composite restoration finishing?
- A A slower procedure overall
- B Insufficient surface gloss on the finished restoration
- C Excessive heat that may damage the resin and tooth
- D Immediate loss of restoration
Correct answer: Excessive heat that may damage the resin and tooth
High speed without water cooling can produce heat that compromises the resin and tooth, potentially causing damage or impaired marginal seal.
Why are multiple abrasive grits used progressively from coarse to fine during finishing and polishing?
- A To reduce the total chairside working time
- B To gradually remove irregularities for a smoother surface
- C To make the surface more porous
- D To deliberately create a macro-texture on the restoration surface
Correct answer: To gradually remove irregularities for a smoother surface
Using abrasives from coarse to fine progressively removes deeper scratches and refines the surface, leading to minimal final roughness and better polish.
Which of the following is NOT an objective of finishing and polishing dental restorations?
- A Minimizing plaque accumulation at the restoration margins
- B Enhancing aesthetic appearance and surface luster
- C Maximal electrical conductivity
- D Reducing wear on opposing teeth and restorative material
Correct answer: Maximal electrical conductivity
Finishing and polishing aim for smoothness, hygiene, aesthetics, and reduced wear; electrical conductivity is not relevant in restorative dentistry.
For posterior composite restorations, which instrument or tool is often used to finish and polish occlusal surfaces effectively?
- A A prophy cup used with pumice as the only instrument
- B Flexible aluminum-oxide discs and polishing points
- C Scissors
- D Stainless steel explorer
Correct answer: Flexible aluminum-oxide discs and polishing points
Flexible abrasive discs and polishing points/cups allow contouring and smoothing of complex occlusal anatomy in posterior composites. Prophy cups alone are insufficient; scissors and explorers are inappropriate.
When should finishing and polishing ideally be done after composite polymerization?
- A Immediately after the light curing step ends completely
- B About 10-15 minutes later, once fully polymerized
- C After 24 hours only
- D Only during a second appointment
Correct answer: About 10-15 minutes later, once fully polymerized
Delaying finishing/polishing for 10–15 minutes after curing allows the composite to reach more complete polymerization, reducing risk of surface damage and improving final surface quality.
What is the likely consequence of inadequate finishing and polishing of a restoration?
- A Enhanced bonding strength between the material and the tooth structure
- B Markedly reduced susceptibility to surface staining over time
- C Increased plaque accumulation, staining and gingival irritation
- D Improved occlusal performance
Correct answer: Increased plaque accumulation, staining and gingival irritation
Rough or irregular surfaces encourage plaque retention and staining, leading to gingival irritation and possible secondary caries; proper polishing prevents this.
Which polishing medium is commonly used as a final step to achieve high luster on composite restorations?
- A Aluminum-oxide polishing paste with a soft rubber cup
- B A coarse diamond bur run at high speed for final gloss
- C Carbon steel bur
- D Sandblasting particles
Correct answer: Aluminum-oxide polishing paste with a soft rubber cup
Aluminum-oxide polishing pastes applied with a soft rubber cup are standard for final surface gloss and smoothness on restorations. Diamond or steel burs are too abrasive for final polish; sandblasting isn’t used clinically for final polish.
For interproximal surfaces of a restoration, what finishing/polishing aid is typically used?
- A A rigid carbide bur used as the only instrument
- B Flexible abrasive finishing strips
- C High-speed diamond bur
- D Prophy cup with abrasive paste
Correct answer: Flexible abrasive finishing strips
Flexible abrasive strips adapt well to proximal contours and are used to smooth and polish interproximal areas without damaging adjacent tooth structure.
Which statement best describes the difference between finishing and polishing in restorative dentistry?
- A Finishing is optional, polishing is mandatory
- B Finishing shapes and smooths; polishing refines to a lustre
- C Polishing is done before finishing
- D Finishing increases roughness, and polishing then increases roughness further
Correct answer: Finishing shapes and smooths; polishing refines to a lustre
Finishing addresses gross shape and margin smoothness; polishing refines the surface to a smooth, shiny finish resembling enamel. The two steps differ in intent and outcome.
Why is it important to maintain minimal surface roughness (< 0.2 µm) on composite restorations after polishing?
- A Because the tongue cannot detect any surface smoother than this
- B To reduce plaque, staining, and improve longevity
- C Because rough surfaces are stronger
- D To increase wear on opposing teeth
Correct answer: To reduce plaque, staining, and improve longevity
A smoother surface reduces plaque accumulation, resists staining, is easier to clean, and thus enhances the restoration’s longevity and oral health.
Which factor can influence the effectiveness of a finishing and polishing procedure on composite restorations?
- A Polishing with a dry high-speed handpiece only
- B High-vacuum suction with water coolant or wet finishing
- C Not using suction to avoid contamination
- D Finishing in a separate room that has no ventilation at all
Correct answer: High-vacuum suction with water coolant or wet finishing
The composite’s filler composition and the choice of instruments and polishing system significantly affect surface roughness and polishability. Materials and technique matter more than patient-related factors.
What is a recommended practice to reduce aerosol and vapour exposure during finishing and polishing of restorations?
- A Polish with a dry high-speed handpiece only
- B Use high-vacuum suction and water coolant or wet finishing
- C Do not use any suction at all in order to avoid cross-contamination
- D Finish in a separate room without ventilation
Correct answer: Use high-vacuum suction and water coolant or wet finishing
Using suction and water coolant or wet finishing minimizes aerosol and vapour, reducing risk of contamination and inhalation hazards for patient and operator.
Which restoration type also requires finishing and polishing similarly to composite restorations, though technique may differ?
- A Direct pulp cap
- B Glass-ionomer cement restorations
- C Orthodontic brackets bonded to enamel
- D Surgical sutures
Correct answer: Glass-ionomer cement restorations
Glass-ionomer cement restorations need finishing and polishing to smooth margins and surfaces, similar to composites, although protocols and abrasives may differ.
Which of the following is true regarding the effect of filler particles on composite polishability during finishing and polishing?
- A Softer fillers reliably lead to a better final polish
- B Harder fillers can protrude as the matrix wears, raising roughness
- C Filler particles have no measurable effect on the polish outcome at all
- D Filler composition only affects color, and never the polish
Correct answer: Harder fillers can protrude as the matrix wears, raising roughness
During polishing, the softer resin matrix may abrade faster than harder filler particles, which can protrude and increase roughness if not properly polished. Good technique balances this effect.
For ceramic or porcelain restorations, why might special polishing systems be needed compared to composite resin restorations?
- A Because ceramic is softer than composite and therefore polishes far too easily
- B Because ceramic needs diamond or specialized abrasives for a smooth finish
- C Because ceramic restorations do not require any polishing at all
- D Because ceramic surfaces are always perfectly smooth right after firing
Correct answer: Because ceramic needs diamond or specialized abrasives for a smooth finish
Ceramic restorations are harder and require special abrasive polishing systems (e.g., diamond-impregnated tools) to produce smooth, enamel-like surfaces and resist staining and plaque.
Which outcome is least likely if a restoration is properly finished and polished?
- A Reduced plaque retention at the restoration margins
- B Improved esthetic integration with the natural teeth
- C Increased marginal chipping right after placement
- D Lower risk of surface staining
Correct answer: Increased marginal chipping right after placement
Proper finishing and polishing reduces roughness and marginal irregularities, thus lowering risk of chipping or marginal failure, and improving hygiene and aesthetics — not increasing chipping.