Pretzl B, El Sayed S, Weber D, Eickholz P, Bäumer A. J Clin Periodontol 2018; 45: 1356–1364.

This study assessed tooth loss in periodontally compromised patients 20 years after active periodontal therapy and detected potential influencing factors for tooth loss on a patient level. From the 100 patients who were re-evaluated ten years after active periodontal therapy, 70 could be re-examined 20 years ± 12 months after active periodontal therapy. Tooth loss during 20 years was detected and based on regression analyses the impact of patient-levelled factors was estimated. Of the 1639 teeth, 201 were lost, resulting in a mean tooth loss rate of 0.14 teeth/patient/year during the 20 years. Mean tooth loss per patient was higher during the second ten years of supportive periodontal therapy compared to the first (1.20 vs. 1.67 teeth/patient). When considering influencing factors: smoking, non-compliance to supportive therapy, age, living as a single person and systemic diseases like diabetes or cardiovascular diseases negatively influenced tooth loss in the long-term.