RESUMEN
Periodontitis is a chronic, multifactorial inflammatory disease characterized by progressive destruction of the tooth-supporting apparatus. Determining tooth prognosis is of central importance in clinical practice to help both the clinician and patient understand the risks and benefits of treatment while shedding light on the patient's long-term periodontal prognosis and aiding in the development of an individualized treatment plan. Several indexing-type systems have been proposed for determining the prognosis of periodontally involved teeth. The periodontal risk score (PRS) is a simple, evidence-based, motivational tool that can be used in daily clinical practice in both healthy and periodontally involved patients. The PRS incorporates systemic and lifestyle prognostic factors to achieve superior predictive accuracy. With the PRS, patients are encouraged to achieve a target score (representing an "excellent" prognosis) that can be realistically attained through compliance with a periodontal maintenance plan. The purpose of this article is to present to clinicians how to implement this evidence-based tool into their daily practices and thus help patients improve their long-term periodontal prognosis.