Lack of evidence on the failure rate of dental implants

A dental implant

Clinical question:

In people with diabetes receiving dental implants, is poor glycaemic control associated with a higher failure rate?

Diabetes is associated with an increased risk of dental implant failure.  This systematic review collated the observational evidence to see whether there is an association with glycaemic control.

The evidence

The reviewers found 14 studies.  The studies were too variable in size, quality and scope to permit combination of the data.  They reported implant failure rates for diabetic patients from 0% to 14.3%.

Appraisal hints

  • The reviewers only looked for evidence in PubMed.  It seems likely that they may have missed important research
  • It’s not clear whether glycaemic control was specified in advance as an important subgroup analysis.
  • Individual study quality was low.
  • What would be the expected failure rate of dental implants.


Oates TW, Huynh-Ba G et al. A critical review of diabetes, glycemic control, and dental implant therapy. Clin Oral Implants Res. 2011 Nov 24. doi: 10.1111/j.1600-0501.2011.02374.x. [Epub ahead of print]