The roof of the mouth often turns yellow when a patient is suffering from oral thrush, according to Allison DiMatteo for the Consumer Guide to Dentistry. Fungal infections, such as oral thrush, cause white, yellow or cream-colored curd-like growths on the roof of the mouth.
Oral thrush not only causes a yellow discoloration but can also cause patients to experience a burning sensation in the mouth, unpleasant tastes, bad breath and sensitivity to spicy and acidic foods, explains DiMatteo. When the lesions are scraped from the roof of the mouth, a painful sensation and bleeding typically follow.
Oral thrush is primarily caused by an overgrowth of yeast present in the mouth that is not properly balanced by helpful bacteria within the body, notes DiMatteo. High blood sugar levels associated with diabetes, dry mouth and prolonged use of asthma inhalers and certain antibiotics can also promote ideal conditions for oral thrush and a yellow discoloration in the roof of the mouth. Tobacco users and smokers are especially prone to this condition. Natural remedies are typically used to treat oral thrush, such as flushing the body with acidic juices to rebalance natural bacteria and yeast. Other remedies include antifungal mouth rinses, creams, oral tablets and lozenges.