Supportive periodontal therapy for high- and low-risk patients.

Aim: The validity of the risk assessment in predicting tooth loss due to periodontitis or disease progression was explored.

Methods: Systemic factors, smoking status, bleeding on probing (BoP) percentage, number of residual pockets (probing pocket depth ≥6 mm), tooth loss, and alveolar bone loss in relation to age were the variables of the risk assessment. Based on an improving or deteriorating risk assessment in 2005 compared with 1999, 89 patients were divided into either a high- or low-risk group. Findings were compared with the 2008 outcome.

Results:   Using BoP≤20% as the cut-off, the relationship between BoP and interleukin-1 genotype status was neither significant in 2005 nor in 2008. Neither the high- nor low-risk group was predictive for tooth loss. Patients displayed similar proportions of probing pocket depths ≥6mm in 2005 and in 2008. Linear stepwise regression analysis demonstrated that only the number of supportive periodontal therapy visits explained the number of teeth lost due to periodontitis (P<0.01).

Conclusions:   The categorization of patients into high- and low-risk groups, according to the periodontal risk assessment model applied within a supportive periodontal therapy period of 3 years, had limitations in predicting future tooth loss.