Objective: Planning and evaluation of oral healthcare systems rely on monitoring of care patterns. Monitoring periodontal care patterns provide information on the burden and occurrence of periodontitis in the population and on the direct financial cost. The aims of the study were to describe patterns in periodontal care among dental care attenders that might incite subsequent investigation and revised treatment guidelines. Secondly, to estimate the direct societal costs of periodontal care. Material and methods: A retrospective register-based study utilising data from the Danish Public Health Insurance which includes all dental care attenders in 2012–2016, three years before and one year after a national risk-based recall maintenance program was rolled out in Denmark. Results: The 2.7 million yearly dental care attenders corresponded to ∼60% of the eligible population and in the range of 20–24% received periodontal care. Total expenditure for periodontal care in Denmark increased by 13% from 2012 to 2016, from €78 to €88 million. The proportion of total healthcare funding spent on periodontal care was 0.61% in 2016. Conclusions: Patients with periodontitis have large out-of-pocket yearly expenses for periodontal care. Despite small changes in periodontal clinical practice that may indicate improved targeting of patients in need of periodontal care, challenges of reaching non-attenders and non-adherence to care are unsolved. More research into outcomes from periodontal therapy in daily practice, seen from both normative and patient perspectives, would help establish knowledge of the efficiency of existing periodontal care systems and help identify barriers and facilitators for attending care in Denmark.