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Orthodontic Treatment Time Calculator

Work out orthodontic treatment time instantly with clear inputs, formula shown and shareable results.

About Orthodontic Treatment Time Calculator

Divides the total required tooth movement by the achievable monthly rate and adds a finishing phase, using the well-established figure of about 1 mm of movement per month.

Formula

Treatment duration

Active months = total movement (mm) / rate (mm/month); total = active months + finishing months

Worked example

With the default values below, Orthodontic Treatment Time Calculator returns Estimated treatment time of 12.0. Change any input above and every figure here is recalculated in your browser.

Inputs used

Total tooth movement requiredaccepts 0.5–20 mm
6 mm
Achievable movement rateaccepts 0.3–2 mm/month
1 mm/month
Finishing and detailing phaseaccepts 1–18 months
6 months

Results

Estimated treatment time
12.0 months
Active alignment phase
6.0 months
Treatment time
1.00 years
Appointments at 6-week intervals
8

Step by step

  1. 1Values used
  2. 2Treatment duration
  3. 3Estimated treatment time= 12.0 months
  4. 4Active alignment phase= 6.0 months
  5. 5Treatment time= 1.00 years
  6. 6Appointments at 6-week intervals= 8

Assumptions and limits

  • The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
  • Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.
  • This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

Frequently Asked Questions

Why about 1 mm a month?

Orthodontic tooth movement is limited by bone remodelling, which proceeds at roughly 1 mm per month regardless of force beyond an optimum.

Do clear aligners take longer?

Comparable for mild to moderate cases; complex cases with extractions generally still favour fixed appliances.

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