Reports & Studies

Peri-implant disease risk assessment

The ‘spider web diagram’ devised by Bern University is intended to help clinicians assess the individual risk profile of patients with periodontitis. You can find more information about this in a previous article (Periodontal maintenance therapy – how often do I need it?). But does such a thing also exist for implant patients? As of this year, the answer is: yes, it does – the Implant Disease Risk Assessment.

This risk assessment tool is available at and was designed by Lisa Heitz-Mayfield and Niklaus Lang. The tool takes the following parameters into account when calculating an individual’s risk:

  • History of periodontal disease, including diagnosis
  • Extent of alveolar bone loss around the teeth as a percentage and in relation to the patient’s age
  • Number of bleeding sites
  • Number of sites with increased probing pocket depth
  • Previous compliance with regard to maintenance therapy
  • Fit and cleanability of implant prosthesis

Based on these parameters, the patient is classified as having a low, moderate or high risk of peri-implant disease. It is also possible to see which items/parameters can be tackled to reduce the patient’s risk.

The reference paper that accompanies this tool contains three examples of a 50-year-old patient with a low, moderate and high risk of peri-implant disease.

Future studies still need to determine the true validity* of this tool. This means they will need to precisely record the extent to which the indicated risk actually corresponds with what is seen in clinics.

*Validity: Validity is a criterion for determining the quality of quantitative research. A measurement is valid if it actually measures what it is meant to measure and thus provides reliable results.


  1. Heitz-Mayfield LJA, Heitz F, Lang NP. Implant Disease Risk Assessment IDRA–a tool for preventing peri-implant disease. Clin Oral Impl Res. 2020;31:397–403.