teeth whitening lecture

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teeth whitening lecture

Transcript of teeth whitening lecture

Restorative Dentistry

MANAGEMENT OF TOOTH DISCOLOURATION

COLOUR

Teeth made of many colours, with natural gradation from the darker cervical to the lighter incisal third

Variation affected by thickness of enamel and dentine, and reflectance of different colours

Blue, green and pink tints in enamel, yellow through to brown shades of dentine beneath

Canine teeth darker than lateral incisors Teeth become darker with age

(secondary/tertiary dentine, tooth wear/dentine exposure)

COLOUR

Tooth colour affected by:

individual interpretation time of day patient positioning/ angle tooth is viewed at hydration of tooth (always take shade at start

of appointment) skin tone (make-up) surrounding conditions (e.g. lighting in clinic)

CLASSIFICATION OF TOOTH DISCOLOURATION

Extrinsic discolouration

Intrinsic discolouration

AETIOLOGY OF DISCOLOURATION

Extrinsic Discolouration: Stains (chromogens) that lies on/attach to the

tooth surface or in the acquired pellicle, or The incorporation of extrinsic stain within the

tooth substance following dental development. It occurs in enamel defects and in the porous surface of exposed dentine (‘stain internalisation’).

Extrinsic Discolouration:

E.g.•Plaque, chromogenenic bacteria•Mouthwashes (chlorhexidine)

•Smoking / chewing tobacco•Beverages (tea, coffee, red wine, cola)•Foods (curry, cooking oils and fried foods, foods with colorings, berries, beetroot)

• Antibiotics (erythromycin, amoxicillin-clavulanic acid)• Iron supplements

AETIOLOGY OF DISCOLOURATION

AETIOLOGY OF DISCOLOURATION

Intrinsic Discolouration: Intrinsic discolouration occurs following a change to the structural composition or thickness of the dental hard tissues.

Pre-eruptive:

Disease:•Haematological diseases•Liver diseases•Diseases of enamel and dentine (e.g. Amelogenesis/ Dentinogenesis imperfecta)

Medication:•Tetracycline, other antibiotic s

Fluorosis stains (excess F)Enamel hypoplasia (trauma or infection)

Post-eruptive:Trauma (e.g. pulpal haemorrhagic products)Primary and secondary cariesTooth wearDental restorative materialsAgeingChemicalsAntibiotics

Minocycline (used to treat acne)

Intrinsic Discolouration:

AETIOLOGY OF DISCOLOURATION

Types of Discoloration Colour Produced

Extrinsic (Direct stains)

Tea, coffee and other foods

Cigarettes/cigars

Plaque/poor oral hygiene

Brown to black

Yellow/brown to black

Yellow/brown

Extrinsic (Indirect stains)

Polyvalent metal salts and cationic antiseptics

e.g. Chlorhexidine

Black and brown

Intrinsic

(Metabolic causes)

e.g. Congenital erythropoietic porphyria

(Inherited causes)

e.g. Amelogenesis Imperfecta

e.g. Dentinogenesis Imperfecta

(Iatrogenic causes)

Tetracycline

Minocycline

Fluorosis

(Traumatic causes)

Enamel hypoplasia

Pulpal haemorrhage products

Root resorption

(Ageing causes)

Purple/brown

Brown or black

Blue-brown (opalescent)

Banding appearance:

classically yellow, brown, blue, black or grey

Grey

White, yellow, grey or black

Brown

Grey black

Pink spot

Yellow

Internalized

Caries

Restorations

Orange to brown

Brown, grey, black

MANAGEMENT OF DISCOLOURED TEETH

Treatment options:

1.No treatment

2.Removal of surface stain

3.Bleaching techniques

4.Operative techniques to mask underlying discolouration Veneers Crowns

Treatment option Indications Advantages Disadvantages

No treatment Patient with poor oral hygiene/ caries/ PA pathology, large ant restorations/crowns

Non invasive, no cost Will not address patients aesthetic concerns

Removal of surface stain

-Scale and polish

-Microabrasion-Extrinsic staining

-Fluorosis, white spot demineralisation, enamel hypoplasia

Non/minimally invasive May not improve aesthetics significantly, may require further Rx

Microabrasion- soft tissue irritation/ excessive tooth prep (technique sensitive)

Bleaching

-Home bleaching, Walking bleach

-See later slides

Non/minimally invasive Cost, limitation on shade improvement (a few shade lighter only), may fail/ need repeating, compliance (home bleaching)

Restorative treatment

-Veneers, crowns

Severely discoloured teeth, e.g. tetracycline staining (may bleach 1st)

Unaesthetic tooth morphology (e.g. AI/DI)

Heavily restored teeth

May achieve a more aesthetic result

Destructive, irreversible (tooth tissue removal), changes natural shape of teeth, cost, maintenance, oral hygiene compliance (interdental cleaning)

To bleach or not to bleach?

GENERAL INDICATIONS

Generalised staining Ageing Extrinsic stain - Smoking and dietary stains

(tea/coffee etc) Fluorosis Tetracycline staining (? in combination with

restorative techniques) Traumatic pulpal changes White spots Brown spots (not as good response)

CONTRAINDICATIONS

Patients with high/unrealistic expectations

Decay and active peri-apical pathology (must be resolved first)

Pregnancy/Breastfeeding

Sensitivity/cracks/exposed dentine

Existing crowns / large restorations (anteriorly)

Elderly patients with visible recession and yellow roots (roots don’t bleach as readily as crowns)

If patients cannot afford changing existing restorations post-bleaching

Effects on

Soft tissues

Cervical resorption

Pulp

Hardness of teeth

Tooth coloured restorations

Adhesive bond strength

-changes composition of enamel and dentine, therefore defer definitive adhesive restorations until 2 weeks (at least 10 days) after bleaching completed

BLEACHING

Definition “any treatment procedure or method a dental professional might prescribe to whiten the color and brighten your teeth”

10-15% carbamide peroxide used as a oral disinfectant since late 1960s – LONG CLINICAL HISTORY

BLEACHING TECHNIQUES

Vital bleaching : • Home use of 10 % (15%, 20% ALSO)

carbamide peroxide in a dental tray• “In office bleaching” (~30% carbamide

peroxide) carried out in single visit (photo initiation) plus additional home use of carbamide peroxide 10% to “top up”

Non-vital bleaching : • (A.k.a Walking bleaching)• The ‘Inside/Outside’ method using 10 %

carbamide peroxide

MATERIALS

1. Hydrogen peroxide (HP): H2O2

2. Carbamide peroxide: CH6N2O3 much more stable than hydrogen peroxide, hence it’s preferred use

• Urea stabilises and buffers HP – shelf life!

• A 10% Carbamide peroxide solution contains 3% HP, 7% Urea

3. Tetrahydrate sodium perborate: NaBO3 (Borax) mixed with water- decomposes to HP.

MATERIALS

Why 10% CP most widely used?

• 10% is the only bleaching concentration approved by the FDI

• Majority of clinical data on 10%, if a lawsuit ensued – could be criticized for using something less well “tested”

• Higher concentrations= increased sensitivity and harmful effects

MODE OF ACTION

Thought to be due to the ingress of oxidisers and oxygenating molecules through enamel micropores.

Break/cleave pigment bonds and allow molecules to diffuse through the tooth

&/or become smaller and absorb less light and hence appear lighter

MODE OF ACTION 2

When bleach is applied to the tooth it passes from the incisal edge to the apex of the tooth through the enamel, dentin & pulp chamber within 5- 15 minutes.

Hydrogen Peroxide breaks down very rapidly to water, an oxygen ion and oxygen free radicals. The 3 or 4 most active free radical species are OH- 95%, OOH- 2.3% & O- 2.3%.

H2O

OOH-

O-

OH-H2o2

O2

MODE OF ACTION 3

The oxygen molecules then

attach to the double carbon

bonds (colour stain molecules) and break them down into

single carbon bonds, thus disfiguring their internal colors.

The Single carbon bonds reflect light and therefore make teeth appear brighter and whiter. The changed molecules are now translucent.

The molecules may also now diffuse through the pores more readily because of their reduced size

OH-

OOH-

O-

DCB

DCB

SCB SCB

BREAK DOWN THE STAIN MOLECULES

Before and after

LEGAL SITUATION

The situation at present is that it is illegal in the UK to supply a product for the purpose of tooth whitening, if that product contains or releases more than 0.1% Hydrogen Peroxide.

Companies are able to supply as a “chemical” only i.e. without instructions for use in bleaching

10% CARBAMIDE PEROXIDE RELEASES ~3% HYDROGEN PEROXIDE

SO ESSENTIALLY IT’S ILLEGAL PRACTICE...

LEGAL SITUATION

However

Chief Dental Officer Statement 2000:

“The Department of Health would not

seek to interfere with a dentist’s

therapeutic decision to utilize a

bleaching technique where a dentist

considers this to be in the best interests

of the patient’s overall oral health care”

LEGAL SITUATION

Tooth whitening update (September 2011)- Dental Protection:

• New European Directive allowing dentists to legally supply products for tooth whitening, which release or contain up to 6% hydrogen peroxide , provided that the patient has been examined by a dentist and the first treatment has been performed by the dentist or under his or her direct supervision.

• Once in place (due for publication in October 2011), the UK Government is obliged to amend the Regulations to reflect this within 12 months.

• 6% HP limit will allow dentists to use 18% CP

GENERAL DENTAL COUNCIL

GDC The GDC believes that it is illegal for non-dental

professionals to be offering tooth whitening treatment.

We advise any member of the public wanting tooth whitening to speak to their dentist.

In our view tooth whitening amounts to the practice of dentistry. The carrying out of dentistry by non-registrants is a criminal offence. We are committed to protecting the public by investigating and prosecuting people who are not registered with us and who perform, or provide clinical advice about, tooth whitening

BEWARE

http://www.smilestudiowirral.co.uk/procedure.html

http://www.circlesmk.co.uk/pages/teeth.html

ETHICAL CONSIDERATIONS

The end point is fixed for all teeth and this must be explained fully to the patient.

The Professional should explain the various treatment options, incuding bleaching alternatives such as toothpastes, OTC, at home tray and in-office so that an informed decision can be made.

You must not lead a patient to believe that in-office bleaching will yield better results than home bleaching.

LIVERPOOL UNIVERSITY DENTAL HOSPITAL

At the LUDH, our bleaching protocol states:

“tooth bleaching should only be done if there is a real, clearly-defined clinical need to provide this form of treatment and not merely for the cosmetic aspirations of a patient”.

Bleaching: Part II

Walking Bleach/ Non-Vital Bleaching

NON-VITAL BLEACHING

Spasser (1961) - sodium perborate sealed within canal (walking bleach)

Nutting and Poe (1963, 1967) – combination walking bleach (perborate and HP)

Now carbamide peroxide 10% used widely Known as walking bleaching

Indications:

To whiten endodontically treated, discolored teeth.

NON-VITAL BLEACHING- RISK:

• External (cervical) resorption, especially when used with thermocatalytic activation (heated instrument within pulp chamber)

• Heithersay found incidence increased when associated with trauma (3.9-9.7%) and orthodontic treatment (24%)

CLINICAL RELEVANCE:

Pre-operative radiograph• ensure no pathology (external resorption)

prior to commencing procedure• medico-legal

Warn patient if previous orthodontic treatment or trauma- higher risk

Sealing GP with a 2mm RMGIC (minimum 2mm to prevent ingress of bleach into pulp chamber

BEFORE AND AFTER:

EXAMPLE NON-VITAL BLEACHING

EXAMPLE NON-VITAL

EXAMPLE NON-VITAL

NON-VITAL BLEACHING

NON-VITAL BLEACHING

WARNINGS

Warn patient:• May not improve shade• May reverse, and patient may need to repeat

procedure in future at own cost• May require other treatment: veneer/crown• Tooth is hollow whilst carrying out bleaching and

patient must be careful, do not bit into hard foods, tooth may fracture!

• Cervical resorption? Previous trauma/ortho• If temp filling lost must see dentist urgently

(walking bleach)

NON-VITAL BLEACHING

1. History taking & examination

2. Examine the radiograph to establish adequate RCF

3. Take shade and photograph

4. Rubber dam isolation- single tooth

5. Remove all filling material and gutta percha 2-3mm apical to CEJ (Williams/PCP 2 probe used).

6. All restorative material must be removed to allow bleaching agent to contact the internal tooth structure.

7. Mix RMGIC and place 2mm thickness to assure a seal. Light cure for 20s.

8. Express Carbamide Peroxide into the cavity (use a small tip, e.g. the tips used for acid etch).

NON-VITAL BLEACHING

9. Place tiny cotton pellet into gel. Leave 1.0 to 1.5mm of space to accommodate the provisional restoration.

10.Place a GIC provisional restorative material to seal the access opening, check occlusion.

11.Repeat the procedure every 3 to 7 days until the desired color change is achieved.

12.Remove provisional restorative material and bleaching material to level of GI sealing material. Rinse and clean access opening. Place a temp restoration.

13.A definitive resin composite restoration of a light colour should not be placed before 14 days after the bleaching process.

“INSIDE-OUTSIDE” BLEACHING

Essentially same technique as Non vital bleaching

1. Pre-op radiograph (assess endo)

2. Re-open access cavity

3. Ensure chamber free of GP

4. Seal off the root filling with resin-modified GIC

5. Place the 10% gel (may be higher) into a single tooth tray with labial and lingual reservoirs.

6. Insert tray into the mouth. Remove excess as necessary. This should be kept in position for at least 2 to 3 hours and preferably overnight.

7. Clean the access cavities out with a toothbrush or interproximal brush.

“INSIDE-OUTSIDE” BLEACHING

8. No limit to how many times the material can be changed and changing the material every 2 to 3 hours will probably speed up the process.

9. The access cavity should ideally left open for no longer than necessary (suggested 3 days?)

10. The chamber should be cleaned out thoroughly and temporised.

11. A definitive resin composite restoration of a light colour should not be placed until 14 days after the bleaching process.

Part III

Home Bleaching

LUDH- PROTOCOL 1- Home Bleaching (aka Night Guard Vital Bleaching)

Make a diagnosis of the cause(s) of discolouration and record this in the notes.

Treatment plan: Discuss the various alternative treatment options to bleaching teeth, e.g. no treatment, veneers, crowns.

Check that the patient is not allergic to peroxide or plastic.

Identify the teeth for bleaching **check their periapical status on radiograph.

PROTOCOL 2

• Record the shade of the discoloured teeth and write that in the notes.

• Photograph if possible (with shade tab)

• Obtain patient consent• Warn restorations will not

change colour*• Take alginate impressions for

tray- lab prescription*• Fit bleaching trays, ensure

good fit and comfortable• Advise patient on procedure-

demo use, give leaflets

PATIENT INFORMATION

PATIENT INFORMATION

Using the 10% CP

(Home Bleaching )

1. Brush teeth and floss as normal before each use.

2. Advise the patient to remove the tip from the syringe containing the 10% carbamide gel and to extrude a little (~1mm) of the gel into the deeper and front parts of the tray. (No more than ½ a syringe). Place gel in the tray on the cheek and the tongue side of the back teeth.

3. Seat the tray over the teeth and press down firmly.

4. A finger, a tissue, or a soft toothbrush should be used to remove excess gel that will flow beyond the edge of the tray.

PATIENT INFORMATION

5. Rinse gently and do not swallow. The tray is usually worn whilst sleeping or a minimum of 2 hours.

6. In the morning, remove the tray and brush the residual gel from the teeth. Rinse out the tray and brush it. Store it in a safe container.

The patient should not eat, drink or smoke while bleaching trays in mouth.

10% CP should not be exposed to heat (decomposes), sunlight or extreme cold. Store in a fridge and keep away from reach of children.

PATIENT INFO 2

• Advise the patient that it will probably take about 2-6 weeks to achieve satisfactory result• Nicotine stain 1-3 months

• Tetracycline stain 2-6 months, sometimes 12

• Further restorations

may be required

POST WHITENING INSTRUCTIONS

The Next 24 – 48 hours are important in enhancing & maximizing whitening results.

Avoid substances which may stain teeth Such as: Red wine, coca cola, coffee, tea

Sensitivity: Teeth can be sensitive for 24-48 hours (esp after in office bleaching). It can range from a dull ache in the teeth to sharp pains various teeth. Take Panadol or Nurofen as required.

SENSITIVITY

55% to 75% of patients experience sensitivity

Cause: •Passage of hydrogen peroxide through enamel and dentine to the pulp•Manipulation of teeth

SENSITIVITY

At risk patients:

Large pulp chambers Exposed root surfaces Abfraction, attrition,

erosion, abrasion lesions Over wearing of trays Improper fit of trays High concentrations of

bleaching agent No long-term effects in

the literature

•Decrease wearing time/concentration

•Desensitizing toothpaste–Potassium nitrate

• works on the nerve of the tooth•10 - 30 mins in a tray

–Neutral Sodium Fluoride •occludes the dentinal tubules ( 4-6 weeks)

•Relief gel, Tooth mousse–Amorphous Calcium Phosphate

TREATMENT OF SENSITIVITY

MAKING THE TRAY

• Take alginate impressions of arch(es) to be bleached

• Technician to cast up and block-out the labial aspects of the teeth to be bleached if using reservoirs- recommended (lab technicians add flowable composite onto labial aspects of teeth)

• Make a thin vacuum-formed soft tray from a thermoplastic material

• Check this carefully on the model to ensure there are no sharp areas of the tray that might irritate the gingival margins.

TRAY DESIGN

TRAY DESIGN

LABORATORY PRESCRIPTION:

Please:

1. Pour study models in dental stone

2. Place composite resin on labial surfaces on e.g. UR5-UL5, LR5-LL5 (+/- palatal surfaces), kept short of gingival margins

3. Make upper and lower full arch, 1mm thickness, soft pull down bleaching trays which are well adapted and trim to the level of the gingival margins

REFERENCES

DENTAL PROTECTION POSITION STATEMENT ON WHITENING

Dr Van Haywood and Dr Harald Heymann published the original technique, called Nightguard Vital Bleaching, in an article in 1989

http://www.dentalprotection.org/United_Kingdom/News_And_Information/Position_Statements/20061014_ps_whitening.aspx

School of Dental Sciences - Liverpool University Dental Hospital

Protocols for Tooth Bleaching/Whitening (AJP)

Suliman 2004 - Dental Update papers (links on vital)

FURTHER READING

1. Greenwall, Linda. Bleaching techniques in restorative dentistry : an illustrated guide

2. Haywood, Van B. TitleTooth whitening : indications and outcomes of nightguard vital bleaching / Van B. Haywood; Quintessence Publishing, 2007.

3. Van Haywood’s article: Frequently Asked Questions About Bleaching; Compendium / April 2003

4. GOLDSTEIN, Ronald E Complete dental bleaching; 1995; Quintessence

5. Sulieman M. An Overview of Bleaching Techniques: 1. History, Chemsitry, Safety and Legal Aspects. Dent Update 2004; 31:608-616

6. Sulieman M. An Overview of Bleaching Techniques: 2. Night Guard Vital Bleaching and Non-Vital Bleaching. Dent Update 2005; 32: 39-46

LUDH- PROTOCOL 1

Make a diagnosis of the cause(s) of discolouration and record this in the notes.

Discuss the various alternative options to bleaching teeth, for instance, veneers, crowns and post crowns.

Check that the patient is not allergic to peroxide or plastic.

Identify the teeth for bleaching **check their periapical status on radiograph.

PROTOCOL 2

• Record the shade of the discoloured teeth and write that in the notes.

• Photograph if possible (with shade tab)

• Record that in the notes and obtain patient consent• Warn restorations will not

change colour*• Take alginate impressions for

tray- lab prescription*• Fit bleaching trays, ensure

good fit and comfortable• Advise patient on procedure-

give leaflets

PROTOCOL 3

• Check for the presence of composites, veneers, crowns at adjacent and opposite teeth and warn patients that these will not change colour with bleaching and may need to be redone if bleaching is undertaken as the colour mismatch may become much more apparent following bleaching.

• If possible draw a diagram to remind the patient of the presence of such restorations and keep a copy in the notes.

• The teeth will change colour with bleaching but the existing composites, veneers, or bridges will not change colour.

• If it is subsequently necessary to make these the same colour as the bleached teeth, significant numbers of restorations may need to be redone.

• White spots will become whiter in initial stages, but almost always revert.

• Record in the notes that this has been discussed

PROTOCOL 4

Advise the patient that the necks of the teeth may take longer to lighten.

If there is a lot of recession – must inform pt root surfaces may not bleach

Temporise carious teeth and leaking restorations. Very old amalgam fillings may leave a dark purple colour on the bleaching tray. It is prudent to polish these restorations with conventional multibladed tungsten carbide burs before commencing.

Bleaching should not be undertaken whilst patients are known to be pregnant or breast-feeding.

HISTORY (adapted from data in Haywood)

 Year Authors Innovation1799 Macintosh Chloride of lime is invented - Called bleaching powder1884 Harlan 1st Hydrogen peroxide use

1958 PearsonUsed 35% HP inside tooth and suggested 25%HP with heated lamp

1961 Spasser Perborate sealed within tooth - "walking bleach"

1965 StewartThermocatalytic Technique - pellet saturated with suoperoxyl and heated with an instrument inside pulp chamber.

1987 FeinmannIn office bleaching using 30% H2O2 and heat from bleaching light

1989 Croll Microabrasion technique1989 Haywood and Heyman 10% CP used in trays overnight "Nightguard Vital Bleaching"1990 Bleaching products available OTC - contraversial !

1991 Bleaching materials were investigated and the FDA called for safety studies. Ban was lifted after 6months

1991 Numerous authors Power bleaching using 30% HP and light activiation1996 Rayto Laser tooth whitening1997 Settembrini et al Inside-Outside bleaching technique1998 Carrilo et al Open pulp chamber with CP inside