Tooth Discoloration
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)
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 DISCOLORATION
- Extrinsic discoloration
- Intrinsic discoloration
AETIOLOGY OF DISCOLORATION
Extrinsic Discoloration:
- 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 Discoloration – 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
Intrinsic Discoloration:
- Intrinsic Discoloration 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 caries
- Tooth wear
- Dental restorative materials
- Ageing
- Chemicals
- Antibiotics
- Minocycline (used to treat acne)
| 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:
- No treatment
- Removal of surface stain
- Bleaching techniques
- Operative techniques to mask underlying Discoloration
- 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 RxMicroabrasion- 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) |
