Dental Abnormality?

My grandson who is 16 years old has an infection in his mouth in the area of his right molar near his sinus. There is pus in the area and it causes a foul smell. His doctor performed a CT scan and advised that his molar may be causing the infection and referred him back to his dentist for surgery, however the doctor advised that surgery may have to be performed by cutting into the face underneath his eye, not through the mouth.  His doctor also prescribed antibiotics for the infection (amoxicillin/clavulanic acid 500 mg).  Is this the correct protocol?  Should he be referred to another specialist, oral/craniofacial doctor perhaps?  I am also very concerned about the infection this molar/sinus is causing as I understand an infection can get into the bloodstream and cause heart damage.  He has seen several; dentists as well and they have all told him they have never seen anything like it.  Any guidance you can provide on this abnormality would be very helpful

[scottma]

Seeing an oral surgeon is advised.