Is it possible to transplant hairs through/between existing hairs? (Photos)

i have thinned areas.currently i am on finasteride for 6 months with very good results.hairloss almost completely stopped and thickens all of my miniauturised hairs.i have thick hair now.but my overall density is very low.is it possible to transplant hairs between existing hairs to improve density without permanent damage to the existing follicles?