• Pigmented deposits found on the tooth
surface is dental stains or extrinsic stains.
• In some conditions the stains will be
incooperated in the tooth structure known
as intrinsic stains.
Cause of dental stains
• Oral cavity is subjected to many exogenous
and endogenous substances that stains the
• Also the oral flora contains many type of
chromogenic deposits which also causes stain
• Intrinsic stains are seen in porphyria,
erythroblastosis fetalis and tetracycline
Types of dental stains
Dental stains are mainly of two types:
• Extrinsic stains.
• Intrinsic stains.
• Extrinsic stains are defined as stains located on
the outer surface of the tooth structure and
caused by topical or extrinsic agents.
• Extrinsic dental stains are caused by predisposing
factors and other factors such as dental plaque
and calculus, foods and beverages, tobacco,
chromogenic bacteria, metallic compounds, and
• Certain factors predispose children and adults to extrinsic
stains, include enamel defects, salivary dysfunction, and
poor oral hygiene.
• Microscopic pits, fissures, and defects in the outer surface
of the enamel are susceptible to the accumulation of stain-
producing food, beverages, tobacco, and other topical
• As saliva plays a major role in the physical removal of food
debris and dental plaque from the outer and interproximal
tooth surfaces, diminished salivary output contributes to
extrinsic discoloration. Decrease in saliva may be caused
due to any disease.
• The most common cause of extrinsic stains is poor oral
• Accumulations of dental plaque, calculus, and food particles cause
brown or black stains .
• Deposition of tannins found in tea, coffee, and other beverages
cause brown stains .
• Tobacco stains from cigarettes, cigars, pipes, and chewing tobacco
cause dark brown and black stains that cover the cervical one third
to one half of the tooth.
• Pan chewing results in a red-black stain on the teeth, gingiva, and
oral mucosal surfaces.
• Metallic compounds are also implicated in dental discolorations
because of the interaction of the metals with dental plaque to
produce surface stains.Industrial exposure to iron, manganese, and
silver may stain the teeth black. Mercury and lead dust can cause a
• Chromogenic bacteria cause stains, typically at the gingival margin of the
tooth. The most common is a black stain caused by Actinomyces species.
The stain is composed of ferric sulfide and is formed by the reaction
between hydrogen sulfide produced by bacterial action and iron in the
saliva and gingival exudates.Green stains are attributed to fluorescent
bacteria and fungi such as Penicillium and Aspergillus species. Orange
stain is less common than green or brown stains and is caused by
chromogenic bacteria such as Flavobacterium lutescens.
• Topical medications cause staining. Such as Chlorhexidine rinse causes
brown staining after several weeks of use, particularly on acrylic and
porcelain restorations.Iron-containing oral solutions used for treatment of
iron deficiency anaemia cause black stains. Potassium permanganate
mouthwash (violet-black stain), silver nitrate (black stain), and stannous
fluoride (brown stain) also can induce dental discolorations. Some
systemic medications (e.g. minocycline, doxycycline) can also cause
Red extrinsic stain at gingival margin and interproximal
and incisal region-habit of chewing pan.
• Intrinsic dental stains are caused by certain
dental materials, dental conditions like caries,
trauma, infections, medications, nutritional
deficiencies, genetic defects and hereditary
diseases (e.g. those affecting enamel and
dentin development or maturation).
Causes of intrinsic dental stains
• Numerous causes for intrinsic tooth discoloration
• Stain distribution varies from localized (e.g. 1 or 2
teeth) to a regional or generalized involvement of
primary and secondary teeth.
• Following are some of the causes of intrinsic
1. Dental materials
• Dental restorations most commonly cause
intrinsic discoloration. Amalgam restorations can
generate corrosion products leaving a gray-black
colour in the tooth, especially in large cavity
preparations with undermined enamel.
• Composites, and glass ionomer and acrylic
restorations gradually can leave a gray hue in the
tooth adjacent to the material.
• Other dental materials that cause intrinsic
discoloration include eugenol, root canal sealers,
and polyantimicrobial pastes.
2. Dental conditions and caries
• The erosion of enamel caused by frequent ingestion of acidic foods
and beverages and from the regurgitation of acid from the stomach
can lead to a yellow tooth discoloration. In patients with anorexia, a
yellow discoloration develops on lingual tooth surfaces where the
acid reflux material makes contact with the teeth.
• Patients with orthodontic brackets are at great risk for caries
because of suboptimal plaque removal. As caries progresses into
the dentin, the overlying translucent enamel reveals the color of
the underlying caries and appears yellowish brown. Extensive caries
that involve destruction of both enamel and dentin produce a color
that ranges from light brown, to dark brown or almost black
• The brown colour is attributed to the formation of Maillard
pigments (reaction between proteins and small aldehydes
produced by cariogenic bacteria), melanin, lipofuscins, and uptake
of various food colours and bacterial pigments.7
In some patients,
the caries process can self-arrest, and remineralisation may occur;
however, the brown discolorations usually remain.
• Trauma to developing/yet unerupted, teeth can disturb
enamel formation and may result in enamel hypoplasia,
which is visualized as a localized opacity on the erupted
tooth. Unerupted permanent incisors commonly are
affected after intrusion injuries to primary incisors in young
children who fall on their faces.
• Trauma that occurs to erupted teeth also causes
discoloration. This discoloration frequently occurs in teeth
that have fully formed roots and have sustained
irreversible pulpal injury caused by avulsions, intrusions, or
fractures involving the pulp chamber. Trauma can cause
intrapulpal hemorrhagic and iron sulfide deposition along
the dentinal tubules, producing a bluish black cast.
Intrinsic dental discoloration caused by trauma to the
mandibular incisors that led to pulpal necrosis.
• Periapical odontogenic infections of the primary teeth can
disrupt normal amelogenesis of the underlying permanent
successors and involve a potential for localized enamel
• Rarely maternal rubella or cytomegalovirus infection and
toxaemia of pregnancy can lead to tooth discoloration.
• Crown formation of the secondary dentition occurs until
the child is aged approximately 8 years. Systemic postnatal
infections (e.g. measles, chicken pox, streptococcal
infections, scarlet fever) can also cause enamel hypoplasia.
The band like discolorations on the tooth are visualized
where the enamel layer has variable thickness and
becomes extrinsically stained after tooth eruption.
• Tetracyclines diffuse through dentin to the enamel interface,
chelating calcium ions and incorporating into hydroxyapatite as a
stable orthophosphate complex. The amount of drug incorporation
is determined by the distribution of tooth discoloration and is
equivalent to serum blood levels and the duration of exposure.
When the affected teeth first erupt, they have a bright-yellow band
like appearance that fluoresces under ultraviolet light, although
upon exposure to sunlight, the color gradually changes to gray or
• Minocycline is a second-generation derivative of tetracycline. The
ingestion of minocycline can lead to a green-gray or blue-gray
intrinsic staining of teeth. Staining occurs during and after the
complete formation and eruption.Minocycline was prescribed for
long-term acne therapy in adolescents and adults, although it is
being replaced by other medications.
• Doxycycline has recently been reported to cause
extrinsic staining of teeth,possibly by binding to
glycoproteins in the dental pellicle in patients
with poor oral hygiene in whom oxidation occurs.
• Dental fluorosis is characterized by enamel
discoloration resulting from subsurface
hypomineralization due to the excessive
ingestion of fluoride during the early maturation
stage of enamel formation.Fluorosis affects
primary and secondary dentitions
Tetracycline staining of mandibular teeth caused by the
ingestion of tetracycline when the patient was aged 3 years.
6. Genetic defects and hereditary
• Genetic defects in enamel or dentin formation include
amelogenesis imperfecta , dentinogenesis imperfecta ,
and dentinal dysplasia . These are hereditary diseases
with a propensity for intrinsic tooth discoloration.
• Amelogenesis imperfecta affects both primary and
• Dentinal Dysplasia occurs in 2 types. Teeth with type 2
DD have a blue, amber, or brown translucence.
• Other hereditary diseases include erythropoietic
porphyria and epidermolysis bullosa (EB).
Erythropoietic porphyria is a rare disease of porphyrin
• Extrinsic stains:
Discoloration include brown, black, gray, green, orange,
and yellow. The scratch test is usually used to distinguish
between extrinsic and intrinsic discoloration.
• Intrinsic stains:
Discoloration colours include brown, black, gray, green,
orange, and yellow. Unlike extrinsic discoloration, teeth
with intrinsic discoloration may be red or pink. Under
ultraviolet light, teeth with tetracycline staining and
congenital porphyria may fluoresce yellow or red,
respectively. Intrinsic discoloration cannot be removed by
using the scratch test.
• Dental treatment of tooth discoloration involves identifying the
etiology and implementing therapy.
• Diet and habits: Extrinsic staining caused by foods, beverages, or
habits (eg, smoking, chewing tobacco) is treated with a thorough
dental prophylaxis and cessation of dietary or other contributory
habits to prevent further staining.
• Tooth brushing: Effective tooth brushing twice a day with a
dentifrice helps to prevent extrinsic staining.
• Professional tooth cleaning: Some extrinsic stains may be removed
with ultrasonic cleaning, rotary polishing with an abrasive
prophylactic paste, or air-jet polishing with an abrasive powder.
However, these modalities can lead to enamel removal; therefore,
their repeated use is undesirable.
• Bleaching (tooth whitening): Early bleaching techniques were
developed almost a century ago, and all of the techniques involved
a process of oxidation. Today, with proper patient selection,
bleaching is a safe, easy, and inexpensive modality that is used to
treat many types of tooth discoloration. Usually, bleaching is not
indicated for the treatment of discoloration of the primary teeth.
Bleaching includes 2 types of techniques: vital and non vital.
– Vital bleaching
• Bleaching of vital teeth is indicated primarily for patients with generalized
yellow, orange, or light brown extrinsic discoloration (including chlorhexidine
staining), it may be helpful in mild cases of tetracycline-induced intrinsic
discoloration and fluorosis.
– Nonvital bleaching
• Nonvital bleaching is indicated for the treatment of teeth with discoloration
secondary to pulpal degeneration. This technique involves placing a mixture
of 30% hydrogen peroxide and sodium perborate into the pulp chamber for as
long as 1 week.
• Consultations with the appropriate medical providers may be
required if the underlying etiology of tooth discoloration is
related to a systemic disease (eg, porphyria, AI).
• Endodontists, prosthodontists, periodontists, and oral and
maxillofacial surgeons and/or dental specialists may assist
• Dentists trained in aesthetic dentistry may provide expert
consultation for cosmetic dental procedures.
• Provide counselling to the patient if the
source of the extrinsic dental staining is the
result of diet or habits (e.g. eating blueberries,
using chewing tobacco).
• Removal of the extrinsic source is critical for
• Recommend all patients to perform daily oral
hygiene by using a toothbrush, a dentifrice
containing, and use dental floss.
• Individuals who wear dentures should brush
the prostheses after each meal to keep the
prostheses free of plaque, calculus, and stains.
Partial and complete removable prostheses
(dentures) should always be removed during