Table 1.

Description of CAST codes

Characteristics	Code	Description	Concept of health
Sound	0	No visible evidence of a distinct carious lesion is present	Healthy
Sealed	1	Pits and/or fissures are at least partially sealed with a sealant material
Restored	2	A cavity is restored with a (in)direct restorative material
Enamel	3	Distinct visual change in enamel only. A clear caries discolouration is visible with or without localised enamel breakdown	Reversible premorbidity
Dentin	4	Internal caries-related discolouration in dentine. The discoloured dentine is visible through enamel which may or may not exhibit a visible localised breakdown of enamel	Morbidity
	5	Distinct cavitation into dentine. The pulp chamber is intact
Pulp	6	Involvement of pulp chamber. Distinct cavitation reaching the pulp chamber or only root fragments are present	Serious morbidity
Abscess/Fistula	7	A pus containing swelling or a pus releasing sinus tract related to a tooth with pulpal involvement
Lost	8	The tooth has been removed because of dental caries	Mortality
Other	9	Does not correspond to any of the other categories