At this point the dentist will use a series of bone drills, each of increasing diameter, to enlarge the pilot hole to a final diameter that is capable of accommodating the tooth implant that has been selected for placement.
{ The diameter of the implant chosen for placement is dependent upon the dimensions of the bone at the implant site. In general, the dentist will want to use as large a diameter tooth implant as is reasonably possible. This is because larger diameter implants are stronger and distribute their loads to the surrounding bone more favorably than comparative smaller ones.
Most dental implants that are placed are approximately 4mm in diameter. Some dentists consider 3.25mm diameter dental implants to be the minimum size that can insure adequate implant strength. Tooth implants greater than 4mm are available but are not widely used because sufficient bone width for these implants is less frequently available. }
At the end of the drilling process an alignment pin will be placed so the dentist can confirm that the hole that has been created meets the needed alignment and depth requirements for the dental implant being placed.
The dentist will now need to use a thread forming tool (a screw tap) to create threads in the bone that correspond with the threads on the implant being placed.
{ Some brands of dental implants have a self-tapping feature. These implants utilize a design where the lower portion of the implant has one or more cutting grooves. As the implant is screwed into place, these cutting surfaces create the needed grooves in the jawbone for the implant's threads. No separate thread tapping step is required. }
Now that the hole has been properly prepared, the dentist can insert the dental implant in the bone. This can be accomplished by either placing the dental implant (via a special adapter) into the dentist's dental drill and letting it slowly screw the implant into place, or else by using a hand wrench and screwing it in place manually.