The cause for this open mouth could be the pre-existing habit that he had.
It is very important to normalise the habit for a healthy well being.
See a nearby dentist
A proper checkup can help in planning better.
Aid of habit breaking appliance can be taken
Actual treatment lies in identifying the cause...which could be some underlying disease... Nasal blockage etc.
Answered2019-01-30 19:16:43
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