What’s the cause of pain in my jaws?

Doctor, I am a 65- year-old man. Every morning, I wake up with pain in my jaws and it gets worse  when I chew while having  breakfast. However, later  on during the day I get better.  Strangely, I experience headaches on the same side where chewing gives me pain.  What is bugging me?  Sincerely, Jones Kakoma 

Bruxism is excessive teeth grinding or jaw clenching which can happen at night or during day. Bruxism inevitably leads to sensitive teeth, aching jaw muscles, headaches and tooth wear.

The pain in the muscles of chewing caused by bruxism can be likened to muscle pain after exercise and hence can be worse during early morning and improve by end of the day.

The pain may be felt over the angle of the jaw or in the same side of the face and may be described as a headache.

 Many times, the joint between the lower and upper jaws (temporomandibular joint) may also become painful, with pain being usually felt just in front of the ear, or inside the ear itself. 

That said, a hole in the upper tooth, a temporomandibular joint age-related arthritis, a sinusitis or even a healed or aborted herpes zoster infection of the facial skin have to be ruled out by your doctor. Many times bruxism is due to teeth that do not come together during chewing (malocclusion), stress, genetic susceptibility, medications or may be associated disease conditions such as parkinsonism which may require addressing where possible.