There are 4 types

I.According to location

i. Pit-and-fissure caries: A caries lesion on a pit-and-fissure area ii. Smooth-surface caries A caries lesion on a smooth tooth surface iii.proximal caries iv. Root caries A caries lesion in the root surface

II. According to clinical management strategy

i. Initial Caries Lesion/Non-cavitated caries lesion/White Spot Lesion: A caries lesion that has not been cavitated. In enamel caries, non-cavitated lesions are also referred to as ‘white spot’ lesions. (Clinically, the distinction between a cavitated and a non-cavitated caries lesion is not as simple as it may seem. Although historically any roughness detectable with a sharp explorer has been considered a cavitated lesion, more recent caries detection guidelines establish that only lesions in which a blunt probe (e.g. WHO [World Health Organization]/ CPI [Community Periodonatal Index]/PSR [Periodontal Screening and Recording] probe) penetrates are to be considered cavitated. This distinction has important implications on lesion management because most initial caries lesions can be arrested or remineralized without any restorative intervention ii. Cavitated caries lesion: A caries lesion that results in the breaking of the integrity of the tooth, or a cavitation. All cavitated lesions would require restorative intervention

III. According to rate of activity

i. Active caries lesion: A caries lesion that is considered to be biologically active, that is, lesion in which tooth demineralization is in frank activity at the time of examination a. Moderate caries lesion: An active caries lesion that may or may not have cavitated but that has not reached the inner one-third of dentin is considered as a moderate caries lesion. This can be observed clinically by microcavitations in the enamel or a grey shadow b. Advanced (deep) caries lesion: A definitely cavitated active caries lesion exposing dentin and that has reached the inner one-third of dentin will be considered an advanced (deep) caries lesion. ii. Inactive caries lesion: A caries lesion that is considered to be biologically inactive at the time of examination, that is, in which tooth demineralization caused by caries may have happened in the past but has stopped and is currently stalled. Also referred to as arrested caries, meaning that the caries process has been arrested but that the clinical signs of the lesion itself are still present iii. Rampant caries: Term used to describe the presence of extensive and multiple cavitated and active caries lesions in the same person. Typically used in association with ‘baby bottle caries’, ‘radiation therapy caries’ or ‘meth-mouth caries’. These terms refer to the etiology of the condition.

IV. According to occurrence

i. Primary caries: A caries lesion not adjacent to an existing restoration or crown ii. Secondary caries: A caries lesion adjacent to an existing restoration, crown or sealant. Other term used is caries adjacent to restorations and sealants (CARS). Also referred to as recurrent caries, implying that a primary caries lesion was restored but that the lesion reoccurred iii. Residual caries: Refers to carious tissue that was not completely excavated prior to placing a restoration. Sometimes residual caries can be difficult to differentiate from secondary caries

V. According to depth of lesion

i. Enamel caries: A caries lesion in enamel, typically indicating that the lesion has not penetrated into dentin. (Note that many lesions detected clinically as enamel caries may very well have extended into dentin histologically.) ii. Dentin caries: A caries lesion extending into dentin

According to cavity treatment

Posterior - pit and fissure => class 1 - proximal => class 2 Anterior - non-incisal => class 3 - incisal => class 4 Both - root caries => class 5 - cuspal attrition=> class 6

Location

Class 1 - conservative - conventional Class 2 - Mesio-occlusal-disto - mesio-occlusal - disto-occlusal - mesial - distal Class 3 - labial - mesial - distal - lingual

Class 4 - Mesio-incisial - Disto-incisial Class 5 - Class 6 - cusp => crowns

Class 1 and class 2 =>amalgam restoration

Reference - strudvents ch 2 pg 37