Modeling the effect of osseointegration on dental implant pullout and torque removal tests

Clin Implant Dent Relat Res. 2018 Oct;20(5):683-691. doi: 10.1111/cid.12645. Epub 2018 Jul 27.

Abstract

Background: Osseointegration of dental implants is a key factor for their success. It can be assessed either by destructive (eg, pullout or torque extraction), or nondestructive methods (eg, resonant frequency analysis). However, as of today there is a scarcity of models that can relate the outcome of destructive tests to the level of osseointegration.

Purpose: To study various percentages of bone to implant bonding (tie) using finite element simulations. While evolutions of the bone mechanical properties are not explicitly taken into account, emphasis is put on the 3-dimensional variable extent of the bone-implant bonding, its statistical distribution, and its influence on the measurable extraction and torque loads, seeking to obtain a quantitative relationship.

Materials and methods: We performed numerical simulations of randomly tied implants and calculated the evolution of the pullout force as well as that of the extraction torque.

Conclusion: Within simplifying assumptions for the osseointegration represented by a tie (as opposed to frictional) constraint, the results of this work indicate that the torque test is more discriminant than the extraction one, while both cannot really discriminate osseointegration levels below a relative variation of 20%.

Keywords: dental implants; finite element; osseointegration; pullout; torque.

MeSH terms

  • Dental Implantation, Endosseous*
  • Dental Implants
  • Dental Restoration Failure
  • Dental Stress Analysis* / methods
  • Humans
  • Models, Statistical
  • Osseointegration
  • Titanium
  • Torque

Substances

  • Dental Implants
  • Titanium