Chin Implant Possible Without Getting Rid of Chin Dimple?

The central dimple is created because of the soft tissue of the chin pad, and not because of the underlying bone. The fibrofatty tissue that creates the central chin pad is more fibrous and condensed in the midline, which creates the central depression or dimple.
Placing a chin implant in the plane deep to this tissue is the norm, described as the sub periosteal pocket. So logically, you can see that it should not have a major influence on the depth of the dimple. I will add, however, that extra volume in this deep plane will make is subtly less evident, similar to blowing up a partially inflated balloon and noticing the outer skin of the balloon is more smooth. This should be a very small change.
The shape of the implant can be selected (and later shaped depending on the type of implant) to maintain the dimple, or the more square contour of the masculine jaw. My preference is for an external approach from an incision hidden under the chin, and a silastic implant.

It's difficult to say without the benefit of a formal evaluation. This is my expertise and a huge portion of my practice. Asymmetry is normal and expected. See an expert who does facial shaping with surgical and non surgical methods to get a comprehensive option. Best, Dr. Emer.

A chin implant should not affect your dimple – if you don't want it to. The dimple is caused by an indentation in the fibrous tissue of the chin. The implant is placed underneath this area and thus may smooth out the dimple slightly. If you tell your facial plastic surgeon that you want to keep the dimple, he or she can add a stitch, if necessary, to maintain the cleft. I hope this helps.

In most instances this the dimple is created by the attachments of the skin to the underlying muscle/bone. These commonly originate from the outer covering of the bone called the periosteum. Most implants are placed under the periosteum. Depending on the technique used for chin enlargement, you have specified an implant, these attachments may be disrupted. The can either be recreated or the implant can be shaped to minimize the effect on the dimple.. Most implants are placed under the outer covering of the bone (periosteum).

Chin implant without affecting the cleft can certainly be done especially if you ask your surgeon about placing an anatomical chin implant that sits directly on the bone. While there may be some initial swelling it should not alter your naturally occurring cleft especially if they use an external approach below the chin rather than going through the mouth. If you get too large of an implant it can also distort the cleft. In any case, I would make sure that you discuss your concerns with your surgeon. I hope this information helps.

As the other surgeons have pointed out, it is most certainly possible to place a chin implant without affecting a dimple. You will notice a change immediatly after surgery because of swelling but as this resolves there should not be any change to your dimple.

The chin implant operation itself will not affect the dimple that is present on the chin because the implant is placed over the bone and is not in the skin or subdermal area where the actual dimple or cleft is located. The patient should be able to keep their dimple or cleft after an implant surgery.

If you use a chin implant to augment the chin then you WILL lose some or all of the dimple.
The only way to keep your dimple is to do an advancement osteotomy. Where the bone of the chin is cut the advanced  and the bone is secured with plates and screws

A chin dimple is nothing more than the attachment of that area of the skin to deeper underlying structures, even as deep as the jaw itself.
A chin implant can be placed either through the mouth OR through the crease on the underside of the chin. Even if it is placed through the underside of the chin, IF the dimple attachment is to the area of the chin where the implant needs to sit, the surgery will result in some smoothing of the ORIGINAL dimple. However, if you convey your wishes to your Plastic surgeon, he / she could recreate the dimple with a few well placed stitches from under the skin to the implant giving you a deeper NEW dimple.
Dr. P. Aldea

It is possible to maintain a chin dimple with a chin augmentation; however, it is not guaranteed, and even if you don't lose the dimple, it may become less noticeable. Make sure you tell the surgeon what you want when you have your consultation so you can discuss the possibilities.