Yes, a sinus infection can certainly effect any part of the mouth. The sinus cavities and the oral cavities are all openly connected. If you have ever had a sinus infection and then you have had a bad taste in your mouth, this connection is the reason for it.
Yes sinus infections affects the three parts such as ear,nose and throat. The sinus problems
are several such as headache, throat pain and sneezing. Every parts are included in our head
i. e. eyes, nose, ear and neck is attached to the head. The sinus problems affects to this parts