chapter 19: teeth whitening materials and procedures

what are the types of stains?

1. extrinsic stains 

2. intrinsic stains 

3. developmental color related stains 

4. medication related tooth discoloration 

what is an extrinsic stain?

on the outside of the tooth 

how do you remove extrinsic stains?

with toothbrush/tooth paste, whitening products

what is important for extrinsic stains?

oral hygiene - chromogenic/pigment producing bacteria

what are intrinsic stains?

stains internally in the tooth structure

what are some causes of intrinsic stains?

1. medication (tetracycline drugs)

2. aging

3. illness with high fevers

4. excessive intake of fluoride

5. trauma to teeth 

6. hereditary conditions 

7. hard to remove stains (amalgam, decay) 

what are some examples of hereditary conditions that can cause intrinsic stains?

1. amelogenesis imperfecta 

2. dentinogenesis imperfecta 

what was peroxide whitening historically used for?

decrease gingival inflammation

when was the first commercially available tooth whitening?

1988

how does whitening work?

1. spaces between enamel rods lead to dentin

2. whitening materials travel through to get to dentin

3. oxidation occurs

4. low/high intensity light can accelerate

what do you need to be careful of when whitening teeth?

carious lesions and leaking restorations

what should you not do before whitening teeth?

acid etching

what materials are used to whiten teeth?

1. hydrogen peroxide (5-40%)

2. carbamide peroxide (10-44%)

what does 10% carbamide peroxide break down to?

3.35% hydrogen peroxide and 6.65% urea 

what does carbamide peroxide contain?

carbopol or glycine

what is carbopol?

a thickening agent

what does glycine do?

slows release

what do you need to do to start the whitening process?

1. initial evaluation 

2. restorative work 

3. check for gingival recession 

what kind of gel is used in an in office whitening procedure?

35% carbamide peroxide gel

what kind of light is used in an office whitening procedure?

high intensity light

what is whitening varnish?

a one time, 30 minute procedure

what is used in whitening varnish?

20% hydrogen peroxide whitening varnish 

what is walking bleach?

in-office mixture of sodium perborate monohydrate and 30% hydrogen peroxide 

what happens when blood seeps into dentinal tubules?

causes intrinsic staining

what needs to be done when blood seeps into dentinal tubules?

endodontic procedure - remove restoration to reveal access canal

what is at risk when whitening teeth?

root resorption risk

what do you check for to avoid root resoprtion?

check if a seal is established

what does ACP stand for?

amorphous calcium phosphate

what are at home whitening procedures made of?

10-45% carbamide peroxide or 6-15% hydrogen peroxide

when are teeth whitening procedures not advised?

1. allergy to products

2. pregnant/nursing

3. open carious lesions

4. cracked enamel

5. sensitive teeth

6. use of medications causing photosensitivity

what percent of hydrogen peroxide are in whitening strips?

10% 

what do whitening rinses contain?

hydrogen peroxide

what do whitening toothpastes contain?

abrasive (hydrated silica or calcium carbonate)

what are side effects of whitening teeth?

1. sensitivity

2. reversible pulpitis

3. may cause clenching/grinding if worn over night

what is reversible pulpitis?

a mild inflammation of the dental pulp

how can one heal from reversible pulpitis?

only once the irritant is removed 

what does reversible pulpitis often cause?

sensitivity to hot/cold stimuli

what needs to be done before beginning whitening procedure?

non-composite dental work

what will not change color?

existing restorations

what is enamel microabrasion?

the removal of non-carious discolorations in the enamel 

what causes enamel microabrasions?

mild fluorosis, hyper-mineralized spots that occurred during enamel development, previous carious white spot lesions

what do enamel microabrasions need to be cleaned with?

pumice

what is the acid slurry used for enamel microabrasions made of?

pumice and 6% hydrochloric acid

how long should a patient use the acid slurry for?

1 minute, up to 2 times