“Do I need to remove the cyst under molar?”

YES. This could be one of several dangerous variants of a lesion, and the only way to determine what it is would be to remove it, send it to a pathologist to look at under a microscope, and get a firm diagnosis. It may lead to the need for further treatment, depending on what it is.

Absolutely should have it biopsied. You don’t know it is a cyst or no dentist can tell you this without prior biopsy to confirm histopathologic diagnosis. Could be something else.

Yes the cyst below the molar May be infected and may expand the jaw bone so it should be removed and biopsied and sent for microscopic pathology evaluation

Depends on what type of cyst, sometimes it is asymptomatic but can turn to something serious. You should have it evaluated by an Oral & maxillofacial Surgeon to rule out any potential serious disease. He/she may able to tell you if you need surgery or not

A cyst under a molar is concerning as one can only make a definitive diagnosis by removing it and having an oral pathologist examine the tissue to arrive at a specific diagnosis. Most cysts are benign, but will in time enlarge to such an extent that damage to the structural integrity of the jaw takes place, damage to adjacent teeth, or extension outside the bone. There are certainly lesions in bone that may appear to be a cyst, but are actually tumors. Discomfort is not the issue with lesions such as this. See an Oral and Maxillofacial Surgeon for appropriate imaging and specific recommendations.