[The values of torque and primary stability of different types of dental implants depending on drill design]

To investigate the values of torque and implant stability quotient of implants with non-aggressive and «active» threads placed using standard spiral and stepped drills.

As the experimental model was used pig's breastbone. Forty implants were divided in two groups which included 10 implants of each type according to thread design. In the first group bone site preparation was conducted with spiral drills, in the second one - using stepped drill. Peek torque values were measured with surgical motor and dynamometric key and to assess implant stability quotient was used Osstell device with Smartpeg and Multipeg pins.

In the first group, there was no significant difference using any type of implant. In the second group, there was a significant increase in the studied parameters during the use of implants with «active» threads with a stepped drill. Torque values increased in 1.7 times. The increase in stability quotient for both Smartpeg and Multipeg pins in average was 8% and 7% respectively. When comparing cylindrical implants with non-aggressive threads with standard drills and conical implants with «active» threads with a stepped drill, the increase of maximum torque and stability quotient was 80%, 8% and 7% respectively.

The use of cylindrical implants with non-aggressive threads when working in low density bone both when using spiral or stepped drills, is characterized by low values of torque and stability quotient. In low density bone the placement of conical implants with «active» threads using a stepped drill is effective.