Objective: To assess tooth loss (TL) in initially periodontally healthy/gingivitis (PHG) and periodontally compromised (PC) individuals during a 15-to 25-year follow-up in a specialist practice and to identify the factors influencing TL.Materials and methods: Patients were re-examined 240 ± 60 months after active periodontal therapy (PC) or initial examination (PHG). PHG patients were periodontally healthy or had gingivitis, and PC patients exhibited at least stage II periodontitis. TL, patient-related outcomes, and risk factors for TL were assessed at the patient level (group-relation, gender, age, smoking, bleeding on probing, educational status, mean number of visits/year).Results: Fifty-six PC patients receiving regular supportive periodontal care (12 female, mean age 49.1 ± 10.9 years, stage II: 10, stage III/IV: 46) lost 38 teeth (0.03 ± 0.05 teeth/year). Fifty-one PHG patients (23 female, mean age 34.5 ± 12.4 years) following regular oral prevention lost 39 teeth (0.04 ± 0.05 teeth/year) (p = .631).Both PC and PHG groups did not show any significant differences regarding visual analogue scale measurements [aesthetics (p = .309), chewing function (p = .362), hygiene (p = .989)] and overall Oral Health Impact Profile (p = .484). Age at the start of follow-up was identified as a risk factor for TL (p < .0001). Conclusion:PC and PHG patients exhibited similarly small TL rates over 240 ± 60 months, which should, however, be interpreted with caution in view of the group heterogeneity.Clinical trial number: DRKS00018840 (URL: https://drks.de).