I have traditional braces to correct my 4mm overjet, midline misalignment and malocclusion on both sides. (Photo)

It is highly unlikely that a 4 mm overjet can be corrected using elastics. You could correct the overjet by extracting your upper bicuspids and retracting your upper incisors but you would NEVER FORGIVE yourself for this outdated and barbaric treatment option. If you extract upper bicuspids and retract your upper incisors you will have either excess space (leaving gaps between your teeth) or overly retracted incisors that will make your upper front teeth look short. You will also lose upper lip support making your upper lip look smaller and causing creases in the corners of your mouth. It will also make your nose look longer, your face look narrow and long and your smile will also be narrower and create black corridors in your smile.PLEASE DO NOT extract any upper teeth!A Herbst appliance is a great option to bring your lower jaw forward and eliminate the 4 mm overjet. As an added benefit, you will have a prettier profile and you will also increase the volume of your airway and increase your TMJ joint space making your joint much healthier.You are FAR better off leaving the 4 mm overjet than extracting upper bicuspid teeth.Good luck!