3213: Dental Formulas

2026-04-04T15:36:33Z

82.132.185.62: /* Explanation */ No you couldn't dental formulae are used for mammals

{{comic
| number = 3213
| date = February 27, 2026
| title = Dental Formulas
| image = dental_formulas_2x.png
| imagesize = 212x337px
| noexpand = true
| titletext = I mean, half of these are undefined. And your multiplication dots are too low; they look like decimal points.
}}

==Explanation==
A {{w|dental formula}} specifies the typical number and location of teeth of each type for a given species. There are two rows, representing the upper and lower jaw, separated by a horizontal line. On each row, the number of each type of tooth is given for one side of the jaw, with dots separating the numbers. The number of {{w|incisors}} is indicated first, {{w|canine teeth|canines}} second, {{w|premolars}} third, and finally {{w|molars}}. The formula in the comic would represent 3 incisors, 1 canine, 3 premolars, and 1 molar on each side of the upper jaw, and equal numbers in the lower jaw, with the exception that there are only 2 premolars; this is the dental formula for the {{w|Felidae|cat family}}. The adult human dental formula is 2.1.2.3 for both the upper and lower jaw.

Cueball is mistakenly treating a dental formula as an arithmetic expression, with the line indicating division and the dots indicating multiplication: 3⋅1⋅3⋅1 divided by 3⋅1⋅2⋅1, giving 9/6 = 3/2. Since the numbers involved are always small natural numbers, calculating the results when treating them this way would be fairly trivial, which is why he is surprised at the effort given to studying them.

In the title text, his statement that half the formulae are undefined refers to animals that lack one of the four types of teeth in the lower jaw, leading to a zero in the lower part of the dental formula. Cueball is attempting to multiply all terms in that lower part, giving a result of zero, and then treat that as a mathematical denominator, resulting in an {{w|Division_by_zero|undefined division expression}}. He also notes that the "dots are too low", as the dots in a dental formula are {{w|Full stop|period characters}}, whereas multiplication in mathematical formulae uses {{w|Interpunct#In_mathematics_and_science|middle dot}} characters (except in the Commonwealth, where this is sometimes reversed).

The word '{{wiktionary|mammologist}}' is an alternate spelling of '{{wiktionary|mammalogist}}', meaning one who studies {{w|mammals}} (or, in some cases, specifically studying the mammaries (i.e. breasts) which mark out mammals in general). Unlike odontology (dentistry, not to be confused with {{w|odonatology}}), which studies the ''health'' of a patient's teeth, mammalogy studies teeth as a means to identify species and what they eat.

The comic's number, 3213, could also be interpreted as (part of) a dental formula, due to having 4 digits, like the four tooth types in the mouth, and having low digits, like a reasonable amount of teeth to find in a mouth. It is missing the lower row though, making it only like half a dental formula.

==Transcript==
:[Cueball and Megan are standing in front of a whiteboard, on which is written
::<u>3.1.3.1</u><br>3.1.2.1
:along with a drawing of a tooth and some other scribbles, two of which look like the letters 'h' & 'j', respectively.]

:Cueball: Do mammologists think these are hard?
:Cueball: I mean, this one just evaluates to 3/2.

:[Caption below the panel:]
:Mathematicians encounter dental formulas

{{comic discussion}}<noinclude>

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Biology]]
[[Category:Math]]

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3213: Dental Formulas