<s>[INST] I suffer from chronic sinus problems - swollen eyes and pain in jaw and teeth on left side.  My dentist says I have fluid under my back molar and need a root canal.  Could the sinus drainage cause this fluid?  I am hesitant to have a root canal done if it is not needed.  I haven't had any pain in the last few months. [/INST] Thanks for your query, I have gone through your query. The pain can be reffered from the sinus to your teeth. Consult a oral physician and get a radiograph done to rule out tooth infection. if the tooth is infected then it has to be root canal treated and cap should be placed. for the pain you can take a course of antibiotics and analgesics. it is better to get the tooth Root canal treated if it is infected, otherwise it has to be removed. i hope my answer will help you, take care. </s>