How long does it take to fix a 1cm overjet with braces?

Orthodontic: It is hard to say without a exam. Many times the patient only see's 1 cm, but other areas need to be adressed. Generally i would presume about 1 1/2 years estimated, maybe sooner.Contact a orthodontist for a consult.

Braces: Did you actually mean 1 cm? I'm afraid that if you meant 1 cm then braces alone will not fix your overjet. You most likely will need jaw surgery in conjunction with your braces. This type of treatment will take time. Best to consult with an orthodontist and oral surgeon to discuss your options.

Overjet: In a 47 year old non-growing adult a 1cm overjet usually signifies extensive skeletal as well as Dental malrelationships. The extent of your malocclusion indicates that you require the services of a fully qualified Orthodontic Specialist and perhaps also an Oral Surgeon. See a Orthodontist for Initial Examination (usually free) and discussion of treatment options and timing.