MAGENT

Modified Mallampati class: the four classes explained

The modified Mallampati scale puts the view of the back of the mouth into one of four classes. Class 1 shows the soft palate, fauces, uvula and pillars; class 4 shows no soft palate at all. Magent's calculator takes the class you assign, 1 to 4, and returns it with a stable label.

Not a medical device. Not a diagnosis or dosing recommendation.

Use this calculator via API

What is the modified Mallampati class?

It's a four-step description of how much of the throat can be seen when a person opens the mouth. The calculator follows G. L. T. Samsoon and J. R. B. Young, who published the modified four-class version in Anaesthesia in 1987. Their abstract describes a link between how hard intubation had been and the anatomy of the oropharynx in the same patient.

The original Mallampati scale from 1985 had three classes. Samsoon and Young added class 4. Magent's calculator uses the four-class version.

This page explains what the four classes describe and what the calculator returns. The calculator doesn't give an intubation-failure probability or a difficult-airway cutoff, and neither does this page.

The Mallampati formula

There's no arithmetic. The class is chosen by the person who looked in the mouth:

class 1 → soft palate, fauces, uvula and pillars visible
class 2 → soft palate, fauces and uvula visible
class 3 → soft palate and base of the uvula visible
class 4 → soft palate not visible at all
maximum = 4

Exact expression the calculator uses:

Modified Mallampati = caller-assigned integer class 1-4 (Samsoon 1987). Max 4

What each class means

ClassWhat can be seenLabel returned
1Soft palate, fauces, uvula, pillarsclass_1
2Soft palate, fauces, uvulaclass_2
3Soft palate, base of uvulaclass_3
4Soft palate not visible at allclass_4

How the class works

  1. Look. Someone examines the open mouth. Magent doesn't look in the mouth.
  2. Pick the class. Match what's visible to one of the four descriptions.
  3. Enter it. The calculator accepts the whole number 1, 2, 3 or 4.
  4. Read it back. It returns the class, the maximum of 4 and the matching label.

The input comes from the user

There's one input, mallampati. Any value other than 1, 2, 3 or 4 is rejected with an error. The calculator doesn't grade the view itself, and it doesn't convert a three-class or Cormack-Lehane result into this scale.

Worked examples

These use Magent's own expected values for the calculator.

Example 1: class 1

  1. Soft palate, fauces, uvula and pillars are all visible.
  2. Input 1 → class 1, label class_1, maximum 4.

Example 2: class 2

  1. Soft palate, fauces and uvula are visible; the pillars aren't.
  2. Input 2 → class 2, label class_2.

Example 3: class 3

  1. Soft palate and the base of the uvula are visible.
  2. Input 3 → class 3, label class_3.

Example 4: class 4

  1. The soft palate can't be seen at all.
  2. Input 4 → class 4, label class_4, the maximum.

History of the modified Mallampati class

The calculator cites Samsoon GLT and Young JRB, Difficult tracheal intubation: a retrospective study, Anaesthesia, 1987 (volume 42, issue 5, pages 487–490). The abstract says the study looked back at patients whose tracheas had been impossible to intubate on an earlier occasion. It began with obstetric patients and was extended to surgical patients outside obstetrics.

When it's used

The 1987 paper looked back at obstetric and surgical patients whose tracheas had been impossible to intubate on an earlier occasion. The class describes the anatomy seen in the mouth; it doesn't measure anything else about the airway.

Where it's used

The class comes from looking into the open mouth at the bedside. The calculator needs no lab values or measurements.

Who uses it

The person who examines the mouth picks the class. The calculator records it and returns a fixed label, which keeps the class in the same format across records.

Limits of the calculation

  • It returns the class you entered. It doesn't examine the airway.
  • It's the modified four-class scale from Samsoon 1987, not the original three-class scale from 1985.
  • It isn't a Cormack-Lehane grade, which describes a different view.
  • It doesn't give a probability of failed intubation or a difficult-airway cutoff.
  • This page doesn't say what to do with a class.

Clinical decisions belong to a qualified clinician who knows the patient.

  • Original Mallampati scale: the earlier three-class version. Magent's calculator doesn't accept it.
  • Cormack-Lehane grade: a separate grading of a different view. It isn't interchangeable with a Mallampati class.
  • Surgical Apgar score is a separate score taken during an operation, from estimated blood loss, the lowest mean arterial pressure and the lowest heart rate.

Glossary

  • Soft palate: the soft back part of the roof of the mouth.
  • Uvula: the small piece of tissue hanging from the soft palate.
  • Fauces: the opening from the mouth into the throat.
  • Pillars: the folds of tissue at each side of the fauces.
  • Oropharynx: the part of the throat behind the mouth.

Common mistakes

  • Entering a three-class result. This calculator uses the four-class modified scale.
  • Entering a Cormack-Lehane grade. It's a different scale.
  • Entering a number outside 1 to 4. It is rejected with an error.
  • Expecting a probability. The calculator returns the class and its label, nothing more.

Source

Samsoon GLT, Young JRB. Difficult tracheal intubation: a retrospective study. Anaesthesia. 1987;42(5):487-490. DOI: 10.1111/j.1365-2044.1987.tb04039.x. PMID: 3592174

Frequently asked questions

What are the Mallampati classes?

Class 1: soft palate, fauces, uvula and pillars visible. Class 2: soft palate, fauces and uvula. Class 3: soft palate and base of the uvula. Class 4: soft palate not visible.

What is the modified Mallampati?

It's the four-class version from Samsoon and Young, 1987, which added class 4 to the original three classes.

Does the calculator work out the class?

No. You assign the class. The calculator returns it with its label and the maximum of 4.

Is the Mallampati class the same as the Cormack-Lehane grade?

No. They're separate scales that describe different views, and the calculator doesn't convert between them.