Reports & Studies

Smoking and increased probing depths are early warning signs

PD Dr. Kristina Bertl, PhD MSc MBA

The prevention and early detection of periodontitis could save our patients lots of treatment time and, most importantly, treatment costs too. In light of this, it may make a lot of sense to make patients aware of obvious risk factors for later occurrence of periodontitis at a young age. But how can we identify when young patients have an increased risk of being affected by periodontitis?

Smoking and increased probing depths are early warning signs
Smoking and increased probing depths are early warning signs

A research group from Sweden recently looked at precisely this question (Trullenque‐Eriksson et al. 2023). The study examined a cohort of 345 19-year-old Swedes (195 women and 150 men) to see how many were diagnosed with periodontitis over a 12-year observation period and what factors increased this risk. Periodontitis was defined in the study as the presence of probing depths of ≥ 6 mm on at least two teeth.

The statistical evaluation revealed the following results:

  • The incidence, i.e. new cases, of periodontitis stood at almost 10%! This in turn means that periodontitis was diagnosed in 33 participants between the ages of 24 and 31 years of age alone!
  • Smoking significantly increased the risk of periodontitis occurring.
  • A higher number of probing depths of 4–5 mm at the age of 19 significantly increased the risk of early occurrence of periodontitis.
  • Interestingly, the following factors had no significant impact on the early occurrence of periodontitis: plaque and bleeding indices, gender, snuff.

Smoking was thus once again revealed to be a clear risk factor for the occurrence of periodontitis. But this is a well-known fact. A more interesting fact revealed by the results of this study is that it was primarily the first signs of increased probing depths at a young age (i.e. < 20 years of age) that were associated with early onset of periodontitis. We should therefore pay particular attention to young patients who are already showing initial signs of disease in the periodontal tissue (= increased probing depths), provide the appropriate treatment, check them more regularly and, above all, provide all patients concerned with adequate explanations and information.


  1. Trullenque‐Eriksson A, Derks J, Skoogh Andersson J. Onset of periodontitis — a registry‐based cohort study. Clinical Oral Investigations (2023) 27:2187–2195.