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Why are the back of my teeth Brown?

Quick Answers

There are a few common reasons why the backs of teeth may turn brown:

  • Poor oral hygiene leading to buildup of plaque and tartar
  • Consumption of staining foods and drinks like coffee, tea, red wine, etc.
  • Use of certain medications like tetracycline
  • Smoking
  • Trauma or injury to the teeth
  • Tooth decay

While brown stains on the back of teeth may seem like just a cosmetic issue, they can indicate more serious dental problems. It’s important to see your dentist if you notice brown stains so the cause can be determined and properly treated if needed.

What Causes Brown Staining on Teeth?

There are several potential causes of brown discoloration on the backs of teeth:

Plaque and Tartar Buildup

One of the most common reasons for brown staining on teeth is a buildup of plaque and tartar. Plaque is a sticky film of bacteria that forms on the teeth. When plaque accumulates, it hardens into tartar which adheres firmly to the tooth surface.

Both plaque and tartar can become stained over time as pigments from food and drinks that you consume get trapped in them. This leads to the development of brown discoloration, usually first appearing on the back surfaces of teeth where plaque and tartar naturally tend to build up more readily.

Poor oral hygiene that allows excessive plaque and tartar accumulation is usually the root cause. Not brushing and flossing thoroughly on a daily basis allows plaque to thrive.

Staining Foods and Drinks

Certain foods, drinks and tobacco products can also lead to brown staining on teeth:

  • Coffee and tea – Contain pigments that can deeply penetrate tooth enamel and dentin, leaving behind stubborn brown stains.
  • Red wine – The pigments in red wine stick to plaque on the teeth and cause brown discoloration.
  • Cola and dark sodas – The caramel coloring contains tannins that can stain teeth.
  • Berries – The anthocyanins that give berries their color can discolor teeth.
  • Soy sauce – The dark pigments can permeate into dental plaque.
  • Tobacco – Tar and nicotine in tobacco sticks to teeth, leaving behind brown stains.

These staining substances make their way into the microscopic holes and ridges on the tooth surfaces and bind to plaque, causing stubborn brown discoloration over time.


Certain prescription medications are associated with brown tooth stains, including:

  • Tetracycline antibiotics – Can cause intrinsic staining of developing teeth in children.
  • Antihistamines – Like Benadryl can have anticholinergic side effects leading to reduced saliva and staining.
  • High blood pressure medications – Like hydrochlorothiazide affect mineralization of teeth.
  • Chemotherapy drugs – Heavy metals in these drugs get deposited on tooth surfaces.

Always tell your dentist about any medications you are taking to discuss potential oral side effects like tooth staining.

Tooth Decay

Untreated tooth decay can also lead to brown discoloration on the backs of teeth. Cavities allow stains to penetrate the porous decayed area more readily. The longer decay goes untreated, the darker the tooth staining becomes from food debris trapped within the cavity.

Dental Trauma

Injury to the teeth from a blow or accident can result in brown staining. Cracks and fractures in the tooth enamel allow stains to seep into the inner layers of the teeth more easily. Chipped and broken teeth are therefore more susceptible to discoloration.


As you get older, the outer enamel layer of your teeth naturally becomes thinner, allowing stains to become more visible and adhere in the tiny holes in enamel. The dentin layer underneath also darkens with age as the tubules widen and pick up more stains.

Moreover, gums recede over time, exposing more of the yellow-brown dentin at the tooth roots and along the backs of teeth.

Which Teeth are Most Affected?

The back teeth, especially molars and premolars, tend to be most affected by brown staining. This is because:

  • Plaque builds up more easily in the harder to reach back areas of the mouth
  • It’s difficult to brush and floss the backs of back teeth thoroughly
  • Grooves and depressions on chewing surfaces collect more food debris
  • Back teeth sustain more wear as they handle most of the chewing force

The upper back teeth tend to be more prone to staining than lower back teeth since saliva does not cleanse them as readily.

As staining progresses with poor oral hygiene, the discoloration can start to appear also on the front and more visible teeth.

Is Brown Tooth Staining Harmful?

While brown stains may seem like just a cosmetic problem, they can potentially indicate:

  • Poor oral hygiene
  • Tooth decay
  • Leaking fillings
  • Excessive plaque and tartar buildup

Visible brown stains on the back of teeth warrant an evaluation by your dentist. The dentist will be able to diagnose the specific cause of staining and provide proper treatment if necessary.

For example, brown stains caused by tooth decay may necessitate filling or crown replacement. Staining due to excessive plaque will require professional cleaning and better at-home oral hygiene.

Allowing brown staining to persist long-term without treatment can potentially lead to more severe consequences like:

  • Tooth decay under plaque deposits
  • Gum disease from tartar building up under the gumline
  • Tooth sensitivity as enamel wears away
  • Tooth loss

How to Prevent Brown Staining on Teeth

You can help prevent brown staining on the backs of teeth by:

  • Brushing thoroughly twice a day – Brush all surfaces for 2 minutes, especially the backs of teeth.
  • Flossing once daily – Make sure to floss behind back teeth where plaque hides.
  • Using antibacterial mouthwash – Helps reduce plaque bacteria between brushing.
  • Seeing your dentist regularly – For professional cleanings and early detection of problems.
  • Limiting staining foods/drinks – Drink dark liquids through a straw to bypass teeth.
  • Quitting tobacco – Avoid smoking and chewing tobacco.

Practicing diligent oral hygiene and seeing your dentist at least twice a year are the best ways to avoid unsightly brown stains on your teeth.

How to Remove Brown Stains on Teeth

If you already have brown stains on your teeth, these methods can help remove them:

  • Professional dental cleaning – Deep cleaning to remove tartar above and below the gumline.
  • Teeth whitening – In-office bleaching or custom take-home trays with whitening gel.
  • Scaling and polishing – Removes external stains from tooth surfaces.
  • Air abrasion – Fine particles sprayed onto teeth to scrub away stains.
  • White filling restoration – Replaces any old fillings that have become stained at the edges.

For significant brown staining, your dentist may recommend a multi-step approach combining deep cleaning, whitening treatments, restorations, and home care. Persistent intrinsic stains may be impossible to remove fully without more aggressive treatments like dental veneers or crowns.

When to See a Dentist

You should make an appointment with your dentist if you notice any of the following:

  • New brown stains appearing on the backs or edges of teeth
  • Stains getting darker or more widespread
  • Existing restorations like fillings or crowns becoming discolored
  • Sensitivity or pain around stained teeth
  • Visible pitting, chipping, or other tooth defects

The dentist can identify what is causing the brown stains and provide appropriate treatment. Prompt action for tooth staining can prevent more extensive dental work being required down the road.


  • Brown stains on the backs of teeth have several potential causes like poor hygiene, staining foods, medications, trauma, tooth decay, and aging.
  • Staining tends to appear first on the back molars and premolars where plaque accumulation is greatest.
  • While mainly a cosmetic issue, brown stains may indicate dental problems needing treatment.
  • Practicing good oral hygiene and avoiding staining substances helps prevent discoloration.
  • See your dentist promptly if you notice new or spreading brown stains.
Cause Contributing Factors Who’s At Risk?
Plaque & Tartar Buildup Poor oral hygiene, inadequate brushing & flossing Anyone with suboptimal oral care habits
Staining Foods & Drinks Coffee, tea, tobacco, red wine, colas, berries, soy sauce Frequent consumers of staining beverages & foods
Medications Tetracycline, antihistamines, blood pressure drugs, chemotherapy Anyone taking medicines with staining side effects
Tooth Decay Destruction of tooth enamel allows stains to penetrate Those with cavities, especially untreated
Trauma Cracks, fractures, chips make tooth vulnerable to stains Those with dental injury from blows, accidents, etc.
Aging Thinning enamel, receding gums, exposed yellowish dentin Older adults as teeth naturally wear

This table summarizes the main causes, contributing factors and those most at risk for brown tooth staining.


Brown stains on the backs of teeth can arise for diverse reasons, but most commonly form due to inadequate oral hygiene allowing buildup of plaque, tartar and debris. Staining foods, medications, dental trauma, tooth decay and aging can also contribute to unsightly discoloration.

While mainly a cosmetic nuisance, brown stains may be a red flag for underlying dental issues needing treatment. Practicing effective daily brushing and flossing and avoiding habits like smoking and frequent coffee drinking can curb staining.

See your dentist right away if you spot brown stains so the cause can be addressed. Surface stains may be removable through professional cleaning and whitening, while intrinsic stains may require restorations or other solutions.