1	DENTAL CARIES its pathology Enamel caries Dentinal caries Root caries BY: DR. KHURRAM ZAFAR www.thedentalclinicpk.com
2	Dental Caries ENAMEL CARIES The early lesion is a white spot which appears on the surface of the enamel the extension of caries is cone shaped with the base towards the outer enamel surface and the apex towards the amelodentinal junction. Caries spreads in zones which are as follows. Translucent zone Dark zone Body of the lesion Surface zone
3	Zones of Enamel Caries
4	Zones of Enamel Caries
5	TRANSLUCENT ZONE Zone of Intial demineralization More porous than the normal enamel. contains 1% by volume space These pores are larger than the normal enamel. Chemical analysis show that there is a fall in the magnesium and carbonate content as compared to the normal enamel
6	Dark zone This zone contains 2-4% by volume pores Some pores are large and some are smaller than the translucent zone suggesting that some remineralization has occurred. In rapidly advancing lesion the dark zone narrow. In this zone previously liberated salts are redeposited
7	Body of the Lesion This zone has pore volume of 5-25% It contains appetite crystals larger than the normal enamel. The is more of an effort for the remineralization but by the further attack there is further dissolution of the mineral Thus this is the zone of maximum demineralization.
8	Surface zone This is about 40 micrometer thick This part is relatively normal because in this area there is maximum remineraization from the inorganic components of both the plaque and saliva.
9	DENTINAL CARIES This differs from the enamel caries as it is a living tissue it responds in a unique way Dentine has a high organic component which consists of predominantly of collagen So there is also a defense mechanism that is activated in the dentine caries by pulp-predentin complex. Caries spreads much faster in this zone because it is much porous and has dentinal tubules. The bacterial stains are capable of releasing large amount of proteolytic enzymes causing damage to dentin.
10	DENTINAL CARIES The events of the dentinal caries are as follows: Defense reaction of the pulpodentinal complex Seclerosis Reactionary dentine formation Sealing of the dead tracts Carious destruction Demineralization proteolysis
11	DENTINAL CARIES
12	DENTINAL CARIES seclerosis and liquefaction
13	ROOT CARIES primary tissue that is effected in the root caries is the cementum. This starts when the root is exposed to the oral environment as a result of the periodontal disease this is followed by the bacterial colonization. There is subsurface demineralization of the cementum and the chain of events is similar in the dentine as it is in the crown portion.
14	ROOT CARIES