**3. Torque at implant placement**

Studies and anecdotal evidence have shown that 30 N/cm is the value considered to be sufficient for primary stability. Below this level, an implant has always been considered highly susceptible to failure by lack of stability. There are two types of torque that we see when placing an implant — insertion torque and seating torque. When immediately loading dental implants, it is the final insertion torque that is the key to successful treatment. In order to follow an immediate load protocol, a minimum seating torque value of 45 N/cm-50 N/cm is necessary [2].

*Webster's Dictionary* defines *torque* as a force to rotate an object about an axis. By Newton's Third law of Motion, we can confidently deduce that the torque value a practitioner gets when placing an implant is equal to the resistance to the original rotational force. Basically, you can turn the implant, which is a screw, until it either cannot move axially in a downward direction anymore or the bone around the implant exceeds its deformational limit and can no longer resist the axial rotation (stripping). This deformational limit will vary from a high value in D1 cortical bone to a lower value in D4 medullary bone.

*RFA and Its Use in Implant Dentistry DOI: http://dx.doi.org/10.5772/intechopen.99054*

The limitation of just looking at torque is that it does not take into account the stability of the implant in lateral directions (**Figure 1**). It is this lateral stability, or resistance to sliding motion between the implant and the osteotomy, that is crucial to success. Therefore, it is possible to have a low torque value with high lateral stability or the opposite situation where you have high rotational stability (torque) and low lateral stability (ISQ) [3].
