I have a open sinus in my upper jaw i had a upper rear tooth removed on my right side last monday one of the roots went thru my sinus it is now open if i gargle water runs out my left nostril. how dangerous it this

You : You need to contact your dentist immediately and be seen by an oral surgeon for possible closure of this oronasal communication. It cannot be left alone.

Sinus : Sinus perforations, called oro-antral perforations, are not uncommon after the extraction of posterior teeth because the roots of these teeth project into the sinus. The perforation typically occurs because an infection has destroyed the bone at the tip of the root or the thin bone was fractured. Typically, the oro-antral is identified at the time of extraction and an attempt is made to close it at that time. If the fistula develops later, or is not immediately identified, it may be closed at a later time. The important thing is for you to be placed on an antibiotic to prevent an infection and an antihistamine to reduce mucus build up in the sinus. Both of these medications will prevent problems from developing and make it easier to close the fistula. Secondary closure will take place after the extraction site has has a chance to heal, in order to reduce the size of the defect, and will typically involve transfer of tissue into the area to cover the fistula. You should contact you dentist for a referral to a board certified oral and maxillofacial surgeon for evaluation and management of this problem.