Brief Answer:
possibly due to tobacco plus changes in tongue bacteria

Detailed Answer:
Hello and welcome,

Tongue discoloration, brown or black can be due to a number of things. From the history you provided, it may be due to tobacco use and possibly difficulty keeping up with oral hygiene due to dentures.

When the small bumps (papillae) on the tongue do not properly shed, it can start to have a black appearance. The changes in appearance to the tongue usually begin toward the back of the tongue and progresses forward toward the front of the tongue.

Inadequate oral hygiene can sometimes cause this as bacteria grow between the papillae. Consider brushing twice a day and replace your toothbrush every 3 to 4 months if you don't already do so.

Heavy tobacco use also changes the chemistry of the tongue and allows bacteria to grow which can make the tongue look black.

Other causes include antibiotics (which changes the normal levels of yeast or bacteria in the mouth); mouth breathing (again - the increased growth of bacteria)

Mouthwashes that contain peroxide or other oxidizing agents can cause black tongue. Also, mouthwashes that contain witch XXXXXXX menthol or other astringents can cause black tongue. Medications that contain bismuth (Pepto Bismol) can stain the tongue.

If at all possible, consider trying to quit smoking cigarettes. It greatly increases your risks of mouth and other head and neck cancers. It is one of the hardest things to quit, but there is help if you are interested. I've had good success with folks who wanted to quit by prescribing Wellbutrin or Zyban. It helps take away the urges for wanting to smoke, and also provides some pick me up that cigarettes normally do. Also, if you smoke more than 1 pack per day, a tapering dose of nicotine patches can help with the physical withdrawal. And there are support groups for helping too.

I hope this information helps. Please let me know if I can provide further information.

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