The Periodontal Screening and Recording (PSR) system is a standardized method used by dental professionals to assess the health of gums and supporting structures. It is an efficient screening tool designed to detect early signs of periodontal disease, a condition involving inflammation and infection. The PSR provides a numerical snapshot of inflammation and pocket depth, helping determine if a comprehensive full-mouth examination is necessary. This screening monitors inflammation levels, offering important clues about both dental health and overall physiological state.
The PSR Scoring System
The PSR examination divides the mouth into six sections, known as sextants, assigning a single code to each. A dental professional uses a specialized periodontal probe with a colored band marked between 3.5 and 5.5 millimeters. The probe is gently placed into the gingival sulcus to measure depth and check for bleeding, calculus, or plaque buildup. Only the highest score found within that sextant is recorded.
Code 0 represents a healthy state: the colored band is fully visible, with no bleeding, calculus, or defective restorative margins detected. Code 1 is assigned when the colored band is visible, but bleeding occurs after probing. Code 2 indicates the colored band remains visible, but calculus (tartar) or faulty dental restorations are present. These lower codes suggest a need for routine cleaning and improved oral hygiene.
Scores of Code 3 and Code 4 signify deeper problems requiring comprehensive treatment. Code 3 is recorded when the colored band is only partially visible, indicating a pocket depth between 3.5 and 5.5 millimeters. Code 4 is given when the colored band completely disappears into the gum pocket, meaning the probing depth is greater than 5.5 millimeters. An asterisk () can be added to note additional issues, such as tooth mobility, gum recession, or furcation involvement.
Periodontal Disease: Causes and Stages
High PSR scores (Code 3 or Code 4) indicate periodontal disease, initiated by the accumulation of bacterial biofilms, or plaque, on the teeth and gum line. If plaque is not removed, it hardens into calculus (tartar), a rough surface where more bacteria thrive. These bacteria release toxins that trigger a chronic inflammatory response in the gum tissue.
The earliest stage is gingivitis, corresponding to PSR Code 1 or Code 2. Gingivitis is characterized by red, swollen gums that bleed easily, but typically involves no irreversible damage to the bone or connective tissue supporting the teeth. This mild inflammation is reversible with professional dental cleaning and diligent at-home oral hygiene.
If gingivitis is untreated, the inflammation progresses into periodontitis, the destructive form of gum disease. The persistent bacterial infection destroys the soft tissue and the alveolar bone anchoring the teeth. As tissue pulls away, deep periodontal pockets form, leading to further bacterial accumulation. This bone destruction defines periodontitis, reflected in Code 3 and Code 4 readings, and can lead to tooth loss.
Connections to Overall Body Health
The inflammation detected by a high PSR score establishes chronic, low-grade inflammation throughout the body. This occurs through the systemic spread of inflammatory mediators and the dissemination of oral bacteria into the bloodstream. The highly vascularized gum tissue provides a direct pathway for infection products to enter systemic circulation.
Once in the bloodstream, inflammatory markers like C-reactive protein contribute to the overall inflammatory burden and are associated with chronic health conditions. Cardiovascular disease is a major link, as chronic inflammation promotes the formation of atherosclerotic plaques (fatty deposits in the arteries). Oral bacteria can also enter the bloodstream (bacteremia) and have been detected in arterial plaque.
The relationship with diabetes is bidirectional. Chronic periodontitis impairs insulin utilization, worsening blood sugar control. Conversely, elevated blood sugar levels make individuals more susceptible to severe gum disease. Periodontitis has also been linked to adverse pregnancy outcomes, including increased risk of preterm birth and low birth weight.