Dental cyst found in 3D x-ray

[ladyjumbles]

Recently I have been to root canal specialist to do root canals for my two upper back molar tooth.
But during an 3D x-ray he found out a hole like in the lower left last molar tooth gums and that tooth area.
Suspected is an cyst, he ask me to look for another expert to confirm whether is a cyst or not.
How many types of cyst are there by the way? How bio scope is done to see the cyst is cancerous or not?
Do the expert in that area need to take a sample of my cells from that suspected area to examine what kind of cyst?
What kind of x-ray needed for checking again whether is a hole shown up in x-ray? Thanks.
Hope my question will be reply soon as October 2nd I will need to visit the expert at National Dental Centre in Singapore.
Meanwhile I feel lost and scare.

 

[honestdoc]

Can you provide images? The only way to diagnose is to biopsy it (remove it and look under a microscope). Chances are in your favor.