Retainers are an essential part of orthodontic treatment, including Invisalign. They are required to maintain the alignment and stability of the teeth after the primary orthodontic treatment is completed.

There are several potential reasons why you may be experiencing jaw muscle pain:

1. Bruxism: Bruxism is a condition in which you grind or clench your teeth, often during sleep. This can put significant strain on your jaw muscles, leading to pain and discomfort.

2. TMJ Disorder: The temporomandibular joint (TMJ) connects the jawbone to the skull. TMJ disorders can cause pain in the jaw muscles, as well as in the joint itself. This can be caused by injury, arthritis, or other factors.

Dental cavities, also known as caries or tooth decay, are damaged areas in the hard surface of your teeth that develop into tiny openings or holes. Cavities are caused by a combination of factors, including bacteria in your mouth, frequent snacking, sipping sugary drinks, and not cleaning your teeth well.