Relationship Between Insertion Torque and Resonance Frequency Measurements, Performed by Resonance Frequency Analysis, in Micromobility of Dental Implants

Abstract

There is an inverse relationship between both ISQ and insertion torque values and implant micromotion under a load of 100 N.

Influence of cortical bone and implant design in the primary stability of dental implants measured by two different devices of resonance frequency analysis: An in vitro study

“…The results of this study also demonstrate significant influence of the implant design on the primary stability of the implant. Upon using implants of the same diameter and length placed following exactly the same milling protocol, Essential Cone implants (Group A) obtained greater primary stability in the block with cortical bone in terms of both insertion torque (32, (18), these levels of torque reduce micromotion, and therefore, the odds of success of the osseointegration process are not increased. Excessive torque can also cause strong compression of the coronal cortical bone, which would result in the appearance of microfractures in and subsequent resorption of the bony trabeculae around the implant (41).…”

“…It is a dynamic parameter that can vary throughout the functional life of the implant, unlike primary, or mechanical, stability, which is a static parameter obtained in a single moment of time on the day of its placement (3,16,17). Primary stability is a purely mechanical concept that results from the friction or resistance between the bone and the implant upon insertion (18,19). Over the years, different methods have been used for the measurement of stability (15).…”

“…Although it has been shown to maintain an inverse relationship with micromotion, statistically it is not linearly but exponentially maintained. Thus, at low torque values, small increases in torque generate large reductions in micromotion, while for high torque values, large increases in torque barely reduce the degree of micromotion (18). Insertion torque can only be measured once, at the time of implant placement.…”

The functional loading of implants increases their stability: A retrospective clinical study

“…The device returns a value expressed as a quotient, in which the value 0 would be the maximum vibration and 100 the lowest possible and which is called the implant stability quotient (ISQ). The ISQ has been demonstrated to be a valid clinical value to monitor the evolution of implant stability, expressing the rigidity of the contact with peri‐implant bone and having a direct linear correlation with implant micromotion before functional loading . It can be explained that as the process of integration of the implant takes place, bone apposition on the titanium surface will change the contour of the implant and thus its natural frequency of vibration.…”

“…The ISQ has been demonstrated to be a valid clinical value to monitor the evolution of implant stability, expressing the rigidity of the contact with periimplant bone 18 and having a direct linear correlation with implant micromotion before functional loading. 19 It can be explained that as the process of integration of the implant takes place, bone apposition on the titanium surface will change the contour of the implant and thus its natural frequency of vibration. Not only that but also the histological modifications (the shift from woven bone to lamellar bone-a result of the adaptation to load) should also be taken as changes in vibration and ultimately in ISQ values, on the basis that they will necessarily determine modifications of the elastic response or even bone mass around the implant.…”