You typically want 2mm all the way around your implant b/c implants require much more bone and biology around them than teeth do. If less than try to favor the buccal bone more (i.e. more bone to buccal of implant than lingual). 1mm only all the way around will not be successful consistently so try to have more bone especially for overdentures b/c crestal bone maintenance can be a little tougher over time for a wide variety of patients.

One tool to keep in mind is mini implants. People love to hate them–but they are great for situations in which you have minimal bone and it may not be feasible or practical to undergo significant grafting.

for example, 80 year old woman that just wants her dentures to not move around. I wouldnt recommend a hip graft. Instead i would use a couple mini’s.