Spots and discolorations under the tongue are very common. If the spots are rechecked after a few weeks, they may resolve on their own. If they haven't, and don't look suspicious, simply observing them to rule out any change in shape or size would be prudent. A biopsy of the area is simple and not very painful, if indicated. Oral cancer can present as a red and or white lesion, though the ventral tongue is not the most likeloy location.
you dentist may not know. if you are concerned, and the dentist does not know, see an oral surgeon for a diagnosis.
Thank you. If it is worth checking out, why at least couldn't the dentist have offered an informed opinion about it? What could be the options? He has two or three spots, one of which is right in the center of the sublingual area. Thanks.
I think this is very normal but it never hurts to get it checked out.