pohc II exam 1

How does fluoride contribute to enamel strength at the molecular level?

It forms fluorapatite, which is more acid-resistant than hydroxyapatite.

Besides strengthening enamel, what are the two other primary mechanisms by which fluoride prevents caries?

Enhancing remineralization and inhibiting bacterial metabolism.

At what stage of tooth development is systemic fluoride incorporated into teeth?

Pre-eruption (during development).

Which mode of fluoride delivery is considered the most important for continuous caries prevention after teeth have erupted?

Topical fluoride.

What is the most economical method of fluoride delivery for a large population?

Community water fluoridation.

What is a primary advantage of water fluoridation over methods like supplements or professional treatments?

It requires no patient compliance.

Under what condition does fluoride overexposure cause dental fluorosis?

Systemic overexposure while teeth are still unerupted.

What are the common professional topical fluoride application formats found in dental offices?

Varnish, foam, and gel.

Why is topical fluoride particularly indicated for patients with xerostomia?

Dry mouth increases caries risk, and fluoride aids in remineralization.

How does topical fluoride benefit patients with exposed root surfaces?

It helps desensitize the root surfaces.

Why is Acidulated Phosphate Fluoride (APF) contraindicated for patients with composite or porcelain restorations?

The acid in APF can etch or damage the surface of esthetic materials.

Which type of professional fluoride is recommended for patients with esthetic restorations like glass ceramics?

Neutral sodium fluoride.

What is the safety status of fluoride intake for fetal development during pregnancy?

Maternal fluoride intake does not harm fetal development.

What is the typical concentration of fluoride in human breast milk?

0.02ppm

What is the recommended amount of fluoride toothpaste for a child under the age of 3?

A smear or rice-sized amount.

What is the recommended amount of fluoride toothpaste for a child between 3 and 6 years old?

A pea-sized amount.

According to the pediatric supplement schedule, what is the daily dose for a 5-year-old child in an area with <0.3 ppm fluoride?

0.5 mg

According to the pediatric supplement schedule, what is the daily dose for a $10$-year-old child in an area with $0.4$ ppm fluoride?

$0.5$ mg

According to the pediatric supplement schedule, what is the daily dose for a child of any age in an area with $>0.6$ ppm fluoride?

$0$ mg

Which topical fluoride product is known for its antimicrobial properties but may cause staining on restorations?

Stannous fluoride (SnF₂)

Which fluoride delivery system is considered the safest and most effective for children due to its high concentration and adherence?

Fluoride varnish.

What is the primary purpose of dental sealants?

To act as a physical barrier preventing bacteria and food from entering pits and fissures.

Which teeth benefit the most from the early placement of sealants?

Newly erupted molars.

How do unfilled sealants differ from filled sealants in terms of clinical performance?

Unfilled sealants offer better penetration into pits but have lower wear resistance.

Why might a clinician need to check the occlusion of a filled sealant more carefully than an unfilled one?

Filled sealants are more durable and may require occlusal adjustment if overfilled.

What is the purpose of using isolation (e.g., cotton rolls or rubber dams) during sealant placement?

To prevent saliva contamination, which interferes with the bond.

What type and concentration of acid is typically used for tooth conditioning before sealant placement?

37% phosphoric acid.

What is the specific visual indicator that a tooth has been successfully etched and dried for a sealant?

A chalky or matte white appearance.

What is the primary advantage of light-cured (photopolymerized) sealants over self-cured systems?

They provide a controlled working time.

After curing a sealant, what tool should be used to check for voids or soft areas?

An explorer.

What should the clinician use to check for high spots or occlusal interference after sealant placement?

Articulation paper.

Why is flossing the interproximal spaces necessary after sealant placement?

To check for and remove any sealant overhangs.

In what clinical scenario are sealants contraindicated for a fully erupted tooth?

When there are existing caries or no deep pits and fissures.

What is a major limitation of prophylaxis polishing pastes regarding oral health?

They are purely aesthetic and do not prevent caries or periodontal disease.

What is the role of humectants in prophylaxis polishing pastes?

To prevent the paste from drying out.

What is the general rule for selecting the grit of a polishing agent?

Always use the least abrasive paste necessary for the task.

Which air-powder polishing material is safest for subgingival biofilm removal?

Glycine.

Why is sodium bicarbonate air-powder contraindicated for patients with uncontrolled diabetes?

Because of its salt content.

Which air-powder material has a Mohs hardness that makes it unsafe for use on teeth or restorative materials?

Calcium sodium phosphosilicate (Novamin).

What was the first material used for air-powder polishing, characterized by a Mohs hardness of $4$?

Aluminum trihydroxide.

Why should clinicians avoid air-powder polishing on patients with sodium-restricted diets, such as those on diuretics?

Risk of sodium absorption from certain powders (like sodium bicarbonate).

Why is respiratory disease (e.g., asthma or COPD) a contraindication for air-powder polishing?

Risk of inhaling aerosols produced during the procedure.

On which restorative materials is air-powder polishing generally considered unsafe?

Porcelain, gold, and some ceramics.

What is the primary purpose of power-driven (ultrasonic) scaling?

To efficiently remove calculus and biofilm.

What are the three common stroke patterns used during ultrasonic scaling?

Vertical, horizontal, and oblique.

What technique prevents the ultrasonic scaling tip from overheating and damaging the tooth?

Maintaining adequate water flow and keeping the tip moving.

What level of pressure should be applied when using an ultrasonic scaler?

Light pressure.

What is the recommended daily fluoride supplement for a $2$-year-old child living in an area with $<0.3$ ppm fluoride?

$0.25$ mg

In sealant tooth preparation, what must be removed before etching?

Debris and calculus.

How long should the tooth be dried after rinsing the etch during a sealant procedure?

$20-30$ seconds.

What is the specific safety requirement for both the patient and clinician when using a curing light?

UV eye protection.

Which air-powder agent is described as gentle and suitable for subgingival biofilm removal similar to glycine?

Erythritol.

How long must a clinician wait for a self-cured sealant to fully polymerize?

$20-30$ seconds.

What visual cue indicates a successful outcome after ultrasonic scaling?

A clean tooth surface and smooth root surface.

Why is renal disease considered a precaution for air-powder polishing?

The body may struggle to process the bicarbonate or other minerals absorbed.