Hi. To know the condition of the different anatomical structures in a joint, u will have to go for something more advanced like a CBCT or even more advanced imaging like MRI (to know the status of your joint cartilage).
I would suggest your to consult a senior Orthodontist, who specialises in TMJ problem first. Let the specialist clinically check and then advise you the appropriate diagnostic imaging modality. TMJ disorders can be treated with removable splints, but you need a permanent solution as splint is a temporary one. One cause of TMJ problems may be the eruption of wisdom teeth also that caused occlusal disturbances (your age suggests that your wisdom teeth would have erupted).
Next Steps
Kindly consult an orthodontist who is specialised in treating TMJ problems.