How much vertical length can a sliding genioplasty add to my chin?

A 10 to 12mm vertical increase would be common in many cases of vertical chin lengthening. The vertical bony gap created is filled with an interpositional allogeneic bone graft. If you want to aesthetically know how much vertical chin lengthening you need, open your mouth and set the chin where its length looks good to you…and then measure the distance between your front teeth. That distance will be how much your chin needs to be vertically lengthened to achieve you aesthetic goals.

I am expert and regular practitioner of osseous genioplasties, and they can be grouped as follows:
1. Sliding genioplasty: ONLY adds anterior projection; does not reduce or add any size; one variation is the overlapping modality, only feasible when maximum advancement is required and a slight vertical shortening is wished; oblique sliding genioplasties may also shorten vertically as well as add projection, but they pinch the labiomental fold ending with very much undesireable results, so not recommended; simple or overlapped (if indicated) sliding genioplasties are very safe, stable and awesome procedures in the right hands; however... they DO NOT add any volume, size or increase vertically or horizontally
2. Multidimensional genioplasties: you can perform one, two or three dimensional works to increase or reduce one, two or all the three dimensions of the chin, and also perform hybrid combinations of, as example, vertical increase and horizontal narrowing, and many others; they are extremely versatile and one of the most amazing fields of facial plastic surgery, notwithstanding practiced by few surgeons; if vertical increase is required you need, as minimum, one dimensional osseous augmentation geniplasty, with as much bone supply as vertical heigth increase is agreed with the surgeon, with bone supply from the elbow or, in large augmentations, from the hip
I have done huge vertical augmentations of 10, 15 and even 20 mm in vertical, normally tall males as you can imagine, and other more subtle in women about 4-8 mm vertical.
If associated to the vertical increase any other feature has to be changed it is compatible, for example anterior augmentation / re-projection or a bit of horizontal narrowing or widening.Do not accept under any circumstances fillers, chin implants or other creative solutions.
If you wish better grounded opinion well lit, focused and standard images have to be assessed: frontal, both lateral and both oblique views.
Feel free to request any additional information from me.