A Retrospective Study on Insertion Torque and Implant Stability Quotient (ISQ) as Stability Parameters for Immediate Loading of Implants in Fresh Extraction Sockets

Biomed Res Int. 2019 Nov 3:2019:9720419. doi: 10.1155/2019/9720419. eCollection 2019.


Background: To date, insertion torque value (ITV) and implant stability quotient (ISQ) obtained by the Osstell instrument are common clinical methods to assess the initial stability of an implant for a predictable loading procedure. The aim of this current study is to evaluate the ITV and ISQ as stability parameters as part of the decision-making protocol in the adoption of immediate loading in fresh extraction sockets.

Materials and methods: A total of 41 tapered implants were allocated into two groups: the test group (n = 11; 3 males and 8 females; mean age: 62.8 ± 10.7) which received 18 implants as type 1 fresh extraction sockets after teeth removal and the control group (n = 7; 4 males and 3 females; mean age: 65.4 ± 9.7) which received 23 implants placed in healed sockets for a period of at least 3 months. Both the ITV and ISQ data were recorded at the time of insertion (t 0). Since ITV (test group) and ITV/ISQ (control group) values were useful for the immediate loading protocol, a screw-retained temporary crown was immediately loaded. ISQ values were recorded after a healing period of 4 months (t 1).

Results: ITV mean values at t 0 in test and control groups were, respectively, 48.61 ± 15.39 and 70.47 ± 14.71, whereas ISQ mean values were 57.55 ± 1.93 and 72.86 ± 5.25, respectively, showing a statistically significant difference (p value < 0.001). ISQ mean values at t 1 in either the test or the control group were 68.68 ± 4.20 and 74.54 ± 4.17, not showing a statistical difference. The implant survival rate was 100% in both groups, and no surgical and prosthetic complications were reported during the study.

Conclusion: In conclusion, this study remarked the presence of a residual gap that influenced the ISQ during implant insertion in fresh extraction sockets making this parameter not sufficient for a conclusive decision in the immediate loading, whereas the ITV alone showed to be the best parameter for a final substantial decision.

MeSH terms

  • Adult
  • Aged
  • Dental Implantation, Endosseous*
  • Dental Implants, Single-Tooth*
  • Female
  • Humans
  • Immediate Dental Implant Loading*
  • Male
  • Middle Aged
  • Retrospective Studies
  • Tooth Extraction
  • Tooth Socket / diagnostic imaging
  • Tooth Socket / surgery
  • Torque