Reports & Studies

Successful treatment – does it make a difference? Part 2

PD Dr. Kristina Bertl, PhD MSc MBA

A while ago, we reported on a study investigating whether the definition of a successfully treated periodontitis patient really does have an impact on the long-term outcome of supportive periodontal treatment („Successful treatment – does it make a difference?''). This study established that the definition of a successfully treated periodontitis patient is extremely strict and not achievable for every patient. Nonetheless, an optimal treatment result has an extremely positive effect on tooth retention in the long term.

Successful treatment – does it make a difference? Part 2
Successful treatment – does it make a difference? Part 2

Several studies on this subject have since been published, and one particular research group from England embarked on a mission to summarise all the literature available on this in a systematic review (Rattu et al. 2023). This project took an in-depth look at the probability of a periodontitis patient being treated successfully and the influence of successful treatment on the rate of tooth loss over the course of the supportive periodontal treatment.

Specifically, different treatment objectives were defined for the start of the supportive periodontal treatment:

  1. Stable treatment outcome (probing depth of ≤ 4 mm, bleeding after probing at < 10%, no bleeding exhibited after probing at a depth of 4 mm)
  2. Periodontal treatment endpoints (no bleeding exhibited after probing at a depth of > 4 mm, no probing depth of ≥ 6 mm)
  3. Disease control (≤ 4 places with a probing depth of ≥ 5 mm)

Looking at these findings, it is immediately clear that there are naturally certain differences and that the first objective is the hardest to achieve, while the third is the easiest. In total, data from 15 studies involving just under 13,000 patients and approximately 323,000 teeth was analysed. What was surprising, however, was that these three objectives were only achieved in a very small percentage of cases:

  1. Stable treatment outcome: 1,4%
  2. Periodontal treatment endpoints: 11%
  3. Disease control: 35%

Around 2,000 of the patients involved underwent supportive periodontal treatment lasting at least five years as a follow-up. Roughly a third of these patients lost one or more teeth over the course of their supportive periodontal treatment, and approximately 3% of all the teeth were lost overall. However, there was a strong correlation between the tooth loss rate and a poorer outcome at the end of the active periodontal treatment. Nevertheless, it is important to bear in mind that this low tooth loss rate relates to a specific pool of patients who all regularly attended their supportive periodontal treatment sessions.

In summary, we can conclude that this review once again demonstrates that commonly used definitions for successful periodontal treatment are extremely difficult to achieve in practice. Nonetheless, the rate of tooth loss is lower when the treatment outcome is better. It is also worth remembering that tooth loss is generally very low in patients who regularly attend supportive periodontal treatment sessions.


  1. Rattu, V., Raindi, D., Antonoglou, G., & Nibali, L. (2023). Prevalence of stable and successfully treated periodontitis subjects and incidence of subsequent tooth loss within supportive periodontal care: A systematic review with meta-analyses. Journal of Clinical Periodontology, 1–19.