Perio Maintenance Interval Calculator

For a patient with a periodontitis history, the every-3-month interval is the typical default for supportive periodontal therapy (SPT), not the exception -- this calculator only extends to 6 months for the low-risk category (composite score under 4 out of a possible ~16), when bleeding on probing is low, residual pocketing is minimal or absent, and there are no significant systemic risk factors like smoking or uncontrolled diabetes. Once the score crosses into moderate or high risk, the interval shortens back to 4 or 3 months because more frequent professional debridement and monitoring reduces the chance that residual inflammation progresses to further attachment loss between visits.

Not by itself -- smoking adds 3 points to the composite score, which alone is not enough to reach the 8-point high-risk threshold from a baseline of zero. It does combine with other factors, though: a smoker who also has several residual deep pockets or uncontrolled diabetes can cross into high risk where a nonsmoker with the same other findings would not.

Both are derived from the same risk category, but they answer different questions. The recall interval tells you how often to schedule visits going forward; the tooth loss estimate (3%, 8%, or 15% for low, moderate, and high risk respectively) is an illustrative, order-of-magnitude figure this calculator assigns to its own risk tiers -- it is not a number published in the Lang & Tonetti PRA paper, which defines the risk categories and recall intervals but not tooth-loss outcome rates, so treat it as a rough directional signal rather than a citation-backed statistic for any individual patient.

Compliance history contributes up to 2 points at its worst rating, while residual pockets 5mm or deeper can contribute up to 4 -- reflecting that objective clinical findings (measured pocket depth, measured bleeding) carry more weight in this adaptation than a subjective compliance rating, even though poor compliance still meaningfully raises the score when combined with other factors.