Tx of intrinsic discolouration Flashcards
What is intrinsic discolouration
occurs beneath the surface of the tooth and occurs when stain causing-particles are able to work their way through the outer layer of your tooth and accumulate within enamel/dentine
What is extrinsic staining
lies on the tooth surface usually caused by tannings
What is required prior to commencing treatment
diagnosis
specialist led treatment plan
informed consent
pre-operative records
What should patient be told to gain informed consent
diagnosis
treatment plan
risk of treatment (including risk of no success)
What pre-operative records do we require
photos
shade sheet
What is on the shade sheet
tooth to be treated
shade of defect
sensibility EPT
sensibility ethyl chloride
What are the treatment options for intrinsic discolouration
- enamel microabrasion
- bleaching
- resin infiltration (ICON)
- localised composite restoration
- veneers
- crowns
- do nothing
What is microabrasion
o Removal of the surface layer of stained opaque enamel to reveal less stained enamel
What are the advantages of microabrasion
Easy
Conservative
Inexpensive
Teeth need minimal subsequent maintenance other than taking care with staining food and drink
Fast acting
Removes yellow/brown, white and multicoloured stain
Effective
Permanent result
Can use before or after bleaching
What are the disadvantages of microabrasion
Removes enamel - sensitivity and prone to stianing
HCL acid - soft tissue damage
Prediction of treatment outcome can be difficult as teeth may appear more yellow as the normal dentine shows through the opaque enamel
Must be done in the dental surgery
Cannot be delegated
100 micron of enamel loss with microabrasion
What is the clinical technique for microabrasion
PPE worn by patient and team
Teeth cleaned with pumice and water
Soft tissue protected using Vaseline
Rubber dam placed
Sodium bicarbonate guard used for gingival protection
HCL pumice slurry used in slowly rotating rubber cup
Should be washed off after every 5 second application, review the colour and the shape
To aid remineralisation, fluoride varnish should be applied
Teeth should be polished with finest sandpaper disc
Polish with toothpaste
Review
How long should the HCl be in contact with the tooth
microabrasion
5 seconds
What is the maximum amount of applications of HCl to the tooth surface
10
What is the name of the fluoride varnish used post-microabrasion
profluorid NOT duraphat
Why is duraphat not used as the varnish of choice
microabrasion
it is yellow
tooth is more prone to stain post microabrasion
profluorid is white
What is the benefit of polishing teeth with finest sandpaper disc
post microabrasion
it helps in changing the optical properties of enamel so that the area of intrinsic discolouration becomes less perceptible (prismless layer of surface enamel created)
What should the patient be warned of (POI microabrasion)
- Teeth are dehydrated after the procedure
- Warn the patient to avoid highly coloured food and drinks for at least 24h, if not longer (avoid food/drinks that would stain a white shirt)
When should the patient be reviewed
- Review patient 4-6 weeks after microabrasion and take post-op photographs
Can a second cycle of microabrasion be taken
Yes but only if maximum result hasn’t been achieved
if no change, second cycle should not be undertaken
Can a third cycle of microabrasion be undertaken
no
second cycle is maximum
What are the 2 microabrasion kits
ultradent
prema kit
What does the GDC state in regards to children + bleaching
GDC stated that tooth whitening products exceeding 0.1-6% hydrogen peroxide shouldn’t be used on under 18s except for when used for the purpose of treating/preventing disease
fluorosis, AI, trauma ect all come under treatment of disease
What is the legal % of hydrogen peroxide that can be used by a dentist
6% unless for treatment/prevention of disease
What is the difference between carbamide peroxide and hydrogen peroxide
Carbamide peroxide breaks down into hydrogen peroxide and urea in an aqueous solution
10% carbamide peroxide turns into 3% hydrogen peroxide
Eventually the hydrogen peroxide turns into water, ammonia and carbon dioxide
What are the 2 types of bleaching
vital and non-vital
What is vital bleaching
it is external bleaching
can still be used on non-vital teeth (if for extrinsic staining)
What are the two types of vital staining
chairside
home
What is chairside bleaching
o Uses unstable, rapidly reacting hydrogen peroxide usually 15-38% which is equivalent to 75% carbamide peroxide
o It poses a greater risk of soft tissues and eyes
What is home bleaching
o Nightguard vital bleaching with 10% carbamide peroxide gel
o Tray designed for bleaching, windows should be cut in the tray over any teeth that you do not want to use
What are the patient instructions for home bleaching
Brush teeth
Apply gel to tray
Wear tray and remove excess
Rinse gently
Wear overnight
Brush teeth day
Keep going for 3-6 weeks until colour achieved
What are the side effects of bleaching
tooth sensitivity
gingival irritation
Why is tooth sensitivity a less common side effects for younger patients
probably due to increased enamel quantity + quality and also larger pulp complexes in adolescent patients teeth which allows faster recovery from acute inflammation experienced
How does bleach cause tooth sensitivity
Due to passage of hydrogen peroxide through intact enamel and dentine, reaching the pulp
What is non vital bleaching
internal bleaching
What are the advantages of internal bleaching
o Simple
o Tooth conserving
o Original tooth morphology
o Gingival tissues not irritated by restoration
o Adolescent gingival level not a restorative consideration
o No lab assistance (only for walking bleach method)
What should we consider when deeming if a tooth is suitable for non vital bleaching
o Requires adequate root filling with no clinical/radiological disease
o Anterior teeth without large restorations
o Not intrinsic staining from amalgam
o Not fluorosis or tetracycline discolouration
What are the 2 non vital bleaching methods
walking bleach
inside out (combination)
What is the walking bleach technique
non vital bleaching
The oxidising process is allowed to proceed gradually over days
What is the technique for the walking bleach technique
- remove root filling 1-2mm below CEJ
- seal root filling with GIC
- place etch to open dentinal tubules for penetration
- sodium perborate placed in pulp chamber
- review patient every 3-4 days for replacement of bleach
- calcium hydroxide dressing placed in pulp chamber for 2 weeks in the interim post bleaching
- final definitive restoraiton placed
When should you stop replacing the bleach
for walking bleach technique
after 3/4 time if no change
up to 6-10 times if change seen
What is the inside out technique
access cavity created
10% carbamide peroxide gel used
Describe the technique for the inside out technique (combination)
- Access cavity created
- Access cleaned with ultrasonic
- 10% carbamide peroxide gel placed within access
- Appropriate part of bleaching tray covering outside of tooth filled with the gel and fitted into mouth
- Should be changed every 2 hours and kept in overnight
- Remove tray when eating and clean out access
What should the definitive restoration be
post nonvital bleaching
White GP and composite resin placed to facilitate rebleaching
OR
Incrementally cured composite which does not leave room for rebleaching but allows for a stronger tooth
OR
Veneer or crown prep if regression
What are the complications of non vital bleaching
- external cervical resorption
- spillage of bleaching agents
- failure to beach
- overbleach
- brittleness of tooth crown
*
How do we try and prevent external crevical resorption
prevent leakage of bleach to surrounding periodontium/external root surface by ensuring sealing material reaches ACJ (walking bleach technique)
calcium hydroxide placement post-bleaching to reverser acidity + prevent bacterial penetration
What is resin infiltration’s brand name
ICON
What is resin infiltration
o The surface layer is eroded, lesions are desiccated and a low viscosity resin infiltrant is applied
o The resin penetrates the lesion by capillary forces
o Infiltrated lesions lose their discoloured appearance and look similar to sound enamel
What should you consider when deciding if a veneer requires enamel preparation
Aesthetic
Relative tooth position (instanding or outstanding)
Masking dark stain
Age
Psyche
Plaque removal
