perforated furcation

I had a root canal done close to 2 years ago. I later had to have the tooth removed and was told it was perforated. I have since still had considerable pain on and off that extends into the sinus. Is that normal and is it possible the bone has not closed or what?

[Jerome Tsang, DDS]

When was the extraction done?  

There could be several possibilities.  It could be a sinus perforation during the extraction that has resulted in a sinus infection.  The pain could be due to a sinus infection initially.  It could be a recent extraction and may take time to heal at this point.