Brief Answer:
Probably a temporomandibular disorder, follow the advice below

Detailed Answer:

Hello,

Your symptoms seem to be related to temporomandibular disorder.
One of the common causes of this diagnosis at your age is rheumatoid arthritis.
Some advice that I can give to you are:     
-Eat a soft diet and cut food into small pieces.
-avoid excessive opening of the mouth
-you can apply cold compresses on the area
-avoid stress and anxiety
-practice exercises of the jaw, especially stretching exercises.
-I also suggest a visit at your dentist for further evaluations.

If the cracking is not associated with pain it does not require any treatment with medication.

Hope my answer was helpful.
If you have any other question Ill be glad to help.
Regards,     
Dr. Dorina Gurabardhi
General &Family Physician

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