Resonance frequency analysis in immediate loading of dental implants

Immediate loading of dental implants aims to shorten treatment time. Stability at implant insertion is critical to success. The aim of this prospective study is to compare primary implant stability, measured by insertion torque (IT) with resonance frequency analysis (RFA) expressed as ISQ. Patients requiring implant therapy were treated by teeth extractions, placement of 1-9 MIS implants, bone augmentation as needed and fixed provisional restorations. We measured IT and ISQ for non-submerged loaded (NSL), non-submerged non loaded (NSNL) and submerged (S) implants. 14 patients, aged 34-79 years, were recruited. 53 implants were inserted (38 maxillary & 15 mandibular). 30 implants, 18 in fresh extraction sites, were immediately loaded. ISQ was 63.3 +/- 2.8 (S.E.), 67.2 +/- 3.5 (S.E.) and 58.8 +/- 2.7 for the NSL, NSNL and S groups, respectively (p = 0.0459). IT was 40.4 +/- 1.8 Ncm, 46 +/- 4.0 and 35.3 +/- 2.1 (p = 0.0646). ISQ and IT were not statistically different between extraction vs. non-extraction and augmented vs. non-augmented sites. We found a significant difference in IT between maxillary & mandibular sites, and a significant correlation between ISQ & IT and between ISQ & implant diameter. These data suggest that ISQ is correlated to IT and is influenced mainly by implant diameter and not by implant length, location or bone level. Finally, a case including immediate implants, bone augmentation and immediate provisional restoration is presented.