<human>: I have a brown area in my mouth on my left cheek. No pain or odor & it has been there for at least two years. I had braces for 3 years and have had then off for 4 years, i wear a removable retainee at nifht that is metal. What is causing the color there?
<bot>: Hello, Thanks for your query. Pigmented entities may arise from intrinsic and extrinsic sources. The color may range from light brown to blue-black. The color depends on the source of the pigment and the depth of the pigment from which the color is derived. Visit the dentist and get it examined. I do hope that you have found something helpful, and I will be glad to answer any further query. Take care