If you have a 1cm over jet and 6-7mm overbite, how long would you have to wear braces?

Depends: 1 cm or 10mm is a large overjet, but this cannot be answered on the net. Age? Angle of the teeth? How compliant will you be with oral hygiene and rubber bands. Too many variables to tell you by computer. A good orthodontist can do this in a reasonable clinical amount of time. Best of luck!

It depends: Its hard to treatment plan without full records, it's better to see and orthodontist and he/she will be able to advice you on treatment time.

Not enough info: What's your jaw relationship, molar and canine relationships, are any teeth missing, crowded, spaced, tipped or twisted? Need more information...See an orthodontist for a thorough examination. Orthodontist. Average time in treatment for adults is 18-24 months.

Depends on treatment: Despite your specific measurements, there is no way to determine an accurate method of treatment without a physical examination and diagnostic records. Certainly, average orthodontic treatments have been demonstrated to be from 2-3 years. Seek an opinion with an orthodontic specialist for more specifics.

Depends: Sorry, i know its not the answer you wanted, but there are so many factors that determine trement time. Oral hygene (healthy gums help teeth move faster), compliance of rubber band wear, otther issues the orthodontist may be trying to address (rotations, crossbites, etc.). While most cases are typically 18-24 months, your orthodontist is the best to provide an estimate for your case.