Dental Whitening, Stains, and Fluoride: Key Concepts for Students

What is the primary purpose of fluoride in dentistry?

Fluoride is used to prevent tooth decay.

What are the two main types of stains on teeth?

Extrinsic stains and intrinsic stains.

What is the difference between extrinsic and intrinsic stains?

Extrinsic stains are on the surface and can be removed, while intrinsic stains are within the tooth structure and are harder to whiten.

What are the typical concentrations of hydrogen peroxide used in whitening?

Hydrogen peroxide is used in concentrations of 5-35%.

What is carbamide peroxide and how does it relate to hydrogen peroxide?

Carbamide peroxide is a weaker oxidizing agent that breaks down into hydrogen peroxide and is used in concentrations of 10-20%.

What is the purpose of custom-made whitening trays?

They are used to apply whitening agents effectively at home.

What is non-vital bleaching?

performed on teeth that have undergone root canal treatment to whiten them.

What is the technique called 'walking bleach'?

involves using sodium perborate mixed with hydrogen peroxide in non-vital teeth for whitening.

What are the steps involved in treating a discolored tooth?

Determine the cause of discoloration, assess the extent of staining, and decide on a restoration vs. whitening procedure.

What is fluorosis and how does it affect tooth appearance?

Fluorosis results from excessive fluoride during tooth formation and can cause white or brown spots and pitting.

What are the characteristics of tetracycline staining?

appears as grey or brown stains and is difficult to whiten.

What is the relationship between intrinsic stains and endodontic therapy?

Endodontic therapy can lead to intrinsic stains as the tooth may darken after treatment.

What are the effects of trauma on tooth color?

Trauma can cause blood from the pulp chamber to extravasate, leading to discoloration.

What is the primary concern when using high concentrations of hydrogen peroxide?

High concentrations can cause reversible pulpitis.

What is the effect of restorative materials on tooth discoloration?

Restorative materials can contribute to tooth staining over time.

What are the two types of peroxide used in at-home whitening products?

Hydrogen peroxide and carbamide peroxide.

What is the range of hydrogen peroxide gel strength for at-home whitening?

2% to 10% for 30 minutes per day.

How long can carbamide peroxide gel be worn for whitening?

From 2 hours up to overnight, depending on the gel's strength.

What is the active ingredient in Crest Whitestrips?

Hydrogen peroxide gel.

What is the primary mechanism of whitening toothpastes?

Mechanical removal of extrinsic stains using abrasive particles.

What are the two main side effects of whitening treatments?

Tooth sensitivity and gingival or mucosal irritation.

How can tooth sensitivity from whitening be managed?

By applying neutral sodium fluoride or potassium nitrate, or using desensitizing toothpaste like Sensodyne.

What are contraindications for tooth whitening?

Anterior restorations, cracked or hypoplastic enamel, carious lesions, cervical abrasions, and light sensitivities.

What bacteria are primarily responsible for carious lesions?

Streptococcus mutans and lactobacilli.

What effect does lactic acid have on enamel?

It lowers the pH in the oral cavity, leading to demineralization of enamel at pH levels below 5.5.

How does fluoride help in tooth remineralization?

Fluoride replaces OH- ions during tooth formation, forming fluorapatite which is harder and less prone to breakdown.

What is the purpose of pit and fissure sealants?

To eliminate vulnerable grooves and pits in teeth before they can break down.

What materials are commonly used for fabricating oral appliances?

Thermoplastic materials, primarily polyethylene.

What is a potential long-term risk associated with excessive bleaching?

The production of free radicals linked to cancers.