My wife has a breathing problem, she faces it when she does not get air from fan specifically and starts breathing from mouth, is this a serious problem and what is the cure.

Dear lybrate-user, the problem of breathing from mouth can occur due to a variety of reasons. First you get her examined from an ent doctor for any obstruction in her throat. Second, you can do is get an oral screen fabricated from a dentist to break this habit, if ent problem is not there. Oral screen is a device made by taking the impression of patient's teeth and oral tissues, and patient needs to wear this on while sleeping. But don't forget, first investigation and'go ahead is needed from ent doctor. All the best.