Tooth loss after periodontal treatment-Mining an insurance database.

Objectives: The aim of this study was to evaluate tooth loss after periodontal treatment.

Methods: The data was collected from the digital database of a major German national health insurance company. Periodontal treatment was the intervention in the treatment group. Kaplan-Meier survival analyses on the patient level with the primary outcome extraction were carried out over four years. A control group without treatment was matched and analysed. Differences were tested with the Log-Rank-test. Extraction incidences were calculated over a matched observation period six years before and four years after treatment for both treatment and control group.

Results: A total of 415,718 periodontal treatments could be traced. Focussing on the outcome "extraction", the cumulative four-year survival rate was 63.8% after periodontal treatment. The matched control group without periodontal treatment showed a survival rate of 72.5%. These differences were significant (p < 0.0001). The extraction incidence over time was higher in a four-year period after periodontal treatment compared to a six-year period before periodontal treatment.

Conclusions: The outcome of periodontal treatment was acceptable. In about two thirds of the patients, extractions could be completely avoided within a four year period after treatment.

Clinical Significance Statement: This study within the German national health insurance system shows that extractions were not observed after periodontal treatment in the majority of cases. Although periodontitis is a chronic disease, patients suffering from periodontitis have a considerable chance to prevent further tooth loss.