How do you Classify Caries?

We have special dental names for where the caries occurs. This is useful to know and understand because we diagnose and treat them slightly differently.

They are:

  • Smooth surface caries. This means decay on the easily seen and cleaned fronts and backs of the front teeth and the sides and insides of back teeth.
  • Approximal or interporximal caries. This means in between the teeth i.e. where the teeth touch the one next door The decay forms just below where the two teeth contact and is why flossing is so important.
  • Pit and fissure caries. This means in thepatterns on top of your back teeth i.e. the grooves and valleysthat can be difficult areas for the bristles of your toothbrush to get into effectively. Caries is difficult to diagnose at the early stage because it forms deep down at the base of the fissure and cannot be easily seen. Another reason why regular visits to the dentist are so important.
  • Root caries. As the name suggests this affects the root surfaces of your teeth and thus they must be exposed to be susceptible e.g. through gum recession from periodontal disease or tooth brush abrasion.

Caries can also be categorized by the site at which it occurs . When the dentist writes up your chart- if you have caries on your teeth- these are the names you are most likely to hear called. They will also call out the tooth number which it relates to:

  • Buccal caries (B)- caries on the outside surface of the tooth, the one facing the cheek
  • Distal caries(D)- caries on the back ‘interproximal’ surface of a tooth
  • Mesial caries (M)- caries on the front of ‘interproximal’ surface of a tooth
  • Palatal Caries (P)- caries on the inside of the tooth on the top teeth; the side facing your palate (roof of your mouth)
  • Lingual caries (L)- caries on the inside surface of the tooth on the bottom teeth; the side facing your tongue and floor of your mouth.
  • Occlusal caries (O)- caries on the biting surface of your back teeth.

Often dental caries doesn’t just affect the single surfaces listed above it goes onto more than one surface; the most common combinations are:

(i) Mesial occlusal caries- abbreviated to MO

(ii) Distal occlusal caries- abbreviated to DO

(iii) Mesial distal occlusal caries- abbreviated to MOD

But could involve any combination such as

Mesial distal occlusal palatal caries abbreviated to MODP

Just to clarify; if you get caries in between your back teeth e.g. mesial (M) caries, the dentist will call out MO because in order to access the caries they must drill through the occlusal (O) surface making the filling an MO- it is impossible to fill this area otherwise. If the tooth next to it however was missing, then the dentist may be able to remove the caries directly in which case it would just be a mesial. I hope that makes sense.

The previous chapter on where you can get caries is also useful reading if you just skipped ahead to this one.