Necessary tests/equipment to know if you really need a rootcanal.i do not want to be misdiagnosed my tooth aches the dds didn't know what was wrong ?

Several choices: Only a dentist can truly diagnose your tooth and what it may need. If a tooth aches spontaneously without any stimulus such as cold, pressure, etc., then it may be infected and need root canal therapy. However, there can be other causes for your pain, such as tooth grinding at night, a gum issue, and too many to speculate here. A few very good x-rays will tell a lot to a very trained eye.

RCT Diagnosis: There are times when an x-ray, pulp test, or symptoms will make the diagnosis obvious regarding the need to do rct on a tooth. There are times when it is the experience and knowledge of the dentist that will dictate the right diagnosis. There are times when waiting until severe pain and swelling will confirm it. It is your choice. Personally, i would trust a qualified endodontist.