Any Completely Scarless Transplant Techniques?

Are there any hair transplant techniques available that allows you to completely shave your head? Or do all of them leave a visible scar of some kind? If they do, how closely cropped does the hair have to be to hide the scar?

The closest thing available is minimal punctate scars that are produced with follicular unit extraction (FUE). The smaller the punch, the less obvious is the scar, but the missing hair follicles become evident if the density is low. In individuals with high density, the use of a 0.7mm – 0.8mm punch will produce an almost scarless appearance, but if you shave your head, you might see it. The hair should be about 1/8th inch long to hide most FUE scars made with small punches.