The first category of basal implants is the BCS implants it’s a polished smooth surface implant and can be used in all the cases where you want to immediate loading there is infection in the socket, there is resorbed bone or you require a massive change in the angulation by bending. There is zero risk of peri implantitis. The second category of implants is the KOS implant or compressive implants as the name suggests these implants are placed in the mouth by under preparation. The drilling is made lesser than the size of implants. This is preferred where there is good available bone. This implant threads is totally roughened.