How to handle sextants with missing posterior tooth?

• A. Ignore the sextant entirely.
• B. Assess the remaining teeth in the sextant; if there are insufficient teeth to score, note as not assessable for that sextant and proceed with others.
• C. Score as zero.
• D. Replace missing posterior teeth before scoring.

Answer: (C)

In periodontal screening, each sextant is scored based on the most clinically significant finding among the teeth present in that sextant. A missing posterior tooth does not automatically raise or lower the code by itself; the score should reflect what is observed on the teeth that remain. If the remaining teeth in that sextant show no signs of periodontal problems—no bleeding on probing, no calculus, and pocket depths within normal limits—the code for that sextant can be zero, indicating a healthy status for that sextant as far as the data allow. The other options would either ignore the sextant, mark it as not assessable, or attempt to replace teeth before scoring, none of which align with applying the recorded clinical findings to that sextant. The key idea is that absence of a tooth doesn't imply disease, so a zero code is appropriate when the available teeth show no periodontal issues.