Today, caries remains one of the most common diseases throughout the world.

Dental caries, also known as tooth decay or a cavity, is an infection, bacterial in origin, that causes demineralization and destruction of the hard tissues of the teeth (enamel, dentin and cementum). It is a result of the production of acids by bacterial fermentation of food debris accumulated on the tooth surface. If demineralization exceeds saliva and other remineralization factors such as from calcium and fluoridated toothpastes, these once hard tissues progressively break down, producing dental caries.



G.V. Black’s Classification of dental caries is the standard method used in identification of carious lesions according to its location on the tooth surface. Black originally devised five classifications, but a sixth was later added.  These cavity classifications are used when recording on the patient’s chart the type of caries found on the teeth.



CLASS I LESIONS:  All pit-and-fissure restorations are Class I, and they involve the following 3 location groups:

– the occlusal surfaces of molars and premolars

– the occlusal two thirds of the buccal and lingual surfaces of molars

– the lingual surfaces of anterior teeth

Class 1 Caries Lesions


CLASS II LESIONS: Involve the proximal surfaces (mesial and distal) of posterior teeth with access established from the occlusal tooth surface. Class 2 Caries Lesions


CLASS III LESIONS: Involve the proximal surfaces of the anterior teeth which may or may not involve the lingual extension but DO NOT involve the incisal line angle. class 3


CLASS IV LESIONS: Involve all proximal surfaces of anterior teeth which also INVOLVE the incisal line angle. class 4


CLASS V LESIONS: Involve the CERVICAL THIRD of all teeth, including the proximal surface of posterior teeth where the marginal ridge is not included in the cavity preparation (Do not involve pit & fissure areas) kk


CLASS VI LESIONS: Involve the incisal edges of all anterior teeth and the cusp tips of all posterior teeth.

Class 6