Examination of Factor to Influence Dental Implant Stability Quotient Change

The success rate of dental implants depends largely on osseointegration of the implant. One method for evaluating osseointegration that has garnered attention is measurement of the implant safety quotient (ISQ) using resonance frequency analysis, but there have been few studies that have observed chronological changes in ISQ in the same implant type. Here, we observed chronological changes in ISQ in high-temperature acid-etched implants. The implants that were studied were 43 Swiss Precision and Innovation implants (SPI (R) implant, Thommen Medical, Grenchen, Switzerland) with a diameter of 4.0 mm that were placed at our clinic in 2017-2018 by the same technician. ISQ was measured at primary and secondary surgery using an Osstell IDx tooth contact analysis device (Osstell AB, Gothenburg, Sweden). Secondary surgery was carried out 6 months after placement in the maxilla and 3 months after placement in the mandible. The ISQ and change in ISQ thus obtained were investigated by placement site. ISQ at primary surgery was significantly higher in the mandible than the maxilla (p<0.001). Change in ISQ from primary to secondary surgery tended to be greater in the maxillary anterior tooth region and the maxillary molar region than the mandibular anterior tooth region and the mandibular molar region. By comparing ISQ from primary to secondary surgery using a single implant type, it was observed that ISQ and change in ISQ varied according to placement site.