When visiting the dentist for a routine exam, patients often hear a series of numbers called out. These measurements represent a detailed, tooth-by-tooth report on the health of the tissues supporting your teeth. The numerical charting procedure is a standard and precise method for tracking even small changes in your mouth over time. Understanding this specialized language is the first step toward taking a more active role in your oral health maintenance. The numbers recorded are the primary indicators dentists use to diagnose and monitor conditions related to the gums and bone structure.
Understanding Periodontal Pocket Depths
The most frequently cited numbers refer to the depth of the gingival sulcus, the shallow, V-shaped space between the tooth and the surrounding gum tissue. A periodontal probe is used to measure this depth in millimeters (mm). The probe is gently inserted to measure the distance from the gum line down to the point where the tissue attaches to the root surface. The measurement is taken at six distinct points around every tooth.
The purpose is to distinguish between a healthy gingival sulcus and a diseased periodontal pocket. When inflammation and disease are present, the attachment point detaches, creating a deeper periodontal pocket that traps bacteria and signals active disease.
The numbers called out are the direct readings recorded into a digital chart. These pocket depths are the primary metric for assessing gum health and are checked regularly to track stability or progression of gum disease. Because a single tooth has six recorded measurements, a patient will hear a long string of numbers, such as “three-two-two, three-three-four,” indicating the depths around that specific tooth.
Interpreting Gum Health Scores
The pocket depth numbers correlate directly to the severity of any underlying gum condition.
Healthy Range (1–3 mm)
A measurement of one to three millimeters (1–3 mm) is generally considered healthy. This indicates the gum tissue is firmly attached to the tooth and the underlying bone fully supports the tooth structure.
Borderline Scores (4 mm)
A measurement of four millimeters (4 mm) signals the need for increased attention and improved home care. A four-millimeter reading can suggest gingivitis (inflammation of the gums) or the beginning stages of periodontitis. At this depth, the pocket can become difficult to clean effectively, allowing bacteria to accumulate.
Diseased Pockets (5 mm or greater)
When measurements reach five millimeters (5 mm) or greater, it indicates periodontitis, a disease involving the loss of supporting bone. The deepening pocket is a direct result of the destructive process below the gum line. Pockets of six millimeters or more often require intensive professional treatment, such as scaling and root planing, to stop the progression of the disease.
Additional Numerical Measurements
Other scores provide additional information about the health of the teeth and gums beyond pocket depths.
Gingival Recession
Gingival recession is measured in millimeters. Recession is the measurement of how far the gum line has pulled away from the tooth’s crown, exposing the root surface. This measurement indicates the distance from the cemento-enamel junction (CEJ)—where the enamel meets the root—to the gum margin. For example, a reading of “2” means the gum has receded two millimeters. This number is tracked because recession exposes the softer root surface, making it vulnerable to decay and sensitivity.
Tooth Mobility
Tooth mobility measures how loose a tooth is, graded on a scale from zero to three. Grade 0 is normal. Grade 1 indicates slight horizontal movement, while Grade 2 signifies a more noticeable horizontal movement. Grade 3 is the most severe, indicating the tooth is loose in both the horizontal and vertical directions, suggesting significant bone loss.
The presence of bleeding upon probing is also tracked, often noted with the letter “B” or a red dot. Bleeding is a sign of inflammation and indicates active gum disease.
How Dentists Identify Specific Teeth
The numerical jargon also includes the method used to identify which tooth is being discussed. Dentists in the United States primarily rely on the Universal Numbering System to label each permanent tooth from one to thirty-two. This system ensures that all dental professionals can clearly and consistently communicate about a specific tooth.
The numbering sequence begins with the upper right third molar, designated as Tooth #1. The numbers proceed sequentially along the upper arch to the left side, ending with Tooth #16. The count then drops to the lower arch, starting with the lower left third molar, Tooth #17, and continues across to the lower right third molar, Tooth #32.
This standardized system means that when a dentist calls out “Number 14,” they are referring to the upper left first molar, or when they mention “Number 25,” they mean the lower right central incisor. While other systems are used internationally, the Universal Numbering System is the standard in American dental offices. By using this consistent numerical identification, dental teams can accurately record all findings, from pocket depths to fillings and crowns, in the patient’s permanent record.