Prof. Asaad Javaid BDS,MCPS,MDS Dept of Restorative Dental Sciences College of Dentistry, Zulfi Majma University

Basics of Dental caries

Learning Objectives Define Caries Define Dental Plaque Describe remineralization / demineralization of hard tooth tissue Name the main causative microorganism of caries Mention various terms used in describing caries Differentiate between incipient and cavitated caries Define rampant caries

Learning Objectives Mention consequences of untreated caries Describe general principle of treating caries Describe the procedure of mechanically removing caries

Definition Dental caries is an infectious disease that results in localized dissolution and destruction of hard tooth tissues Moreover, caries is episodic with alternating phases of demineralization & remineralization

Caries occurrence Dental Plaque consisting of bacteria, is formed on the tooth surface Some bacteria are ACIDOGENIC & produce acid The acid lowers pH

Dental Plaque The diverse community of microbes found on tooth surface as biofilm embedded in an extracellular matrix of polymers of host and microbial origin

Demineralization Loss of mineral content from mineralized tissues of the tooth occurs due to drop in pH The enamel becomes unsupported and crumbles leading to cavitation

Remineralization Due to buffering of saliva, pH become normal in minutes and the tooth tissues absorb Ca and other minerals from saliva and get remineralized

Role of diet in caries Diet plays a significant role in the carious process because the bacteria in the plaque are capable of fermenting a suitable dietary carbohydrate substrate (such as sucrose and glucose) to produce acid, causing the plaque pH to fall within 1–3 minutes

Fermentation التخمير

Main causative organism Streptococcus mutans Streptococcus sobrinus Lactobacilli

Classification Caries can be described according to Virginity of tooth Location Extent Rate

Virginity of tooth Primary caries Secondary caries

Primary caries Primary caries is the original carious lesion of the tooth

Secondary caries The carious lesion that occurs around the margins of an existing restoration and progresses under the restoration it is also known as RECURRENT CAREIS

Location In enamel pits & fissures On enamel smooth surfaces On root surfaces

Pit fissure caries The caries forms a small area of penetration in the enamel at the bottom of a pit or fissure and does not spread laterally to a great extent until the DEJ is reached

Pit fissure caries Once reaches DEJ disintegration spreads along the junction and begins to penetrate the dentin toward the pulp via the dentinal tubules and appear as cone

Smooth surface caries Smooth-surface caries does not begin in an enamel defect, but rather in a smooth area of the enamel surface that is habitually unclean, and is thereby continually covered by plaque

Smooth Surface The disintegration in the enamel in smooth- surface caries also may be pictured as a cone, but with its base on the enamel surface and the apex directed to DEJ

Backward caries When the spread of caries along DEJ exceeds the caries in the contiguous enamel caries extends into this enamel from the junction and is termed backward caries

Forward caries Forward caries is wherever caries cone in enamel is larger or at least the same size as that in dentin

Residual caries Residual caries is caries that remains in a completed tooth preparation, whether by operator intention or by accident. Such caries is not acceptable if at the DEJ or on the prepared enamel tooth wall

Root caries Root caries occurs on the root that has been both exposed to the oral environment and habitually covered with plaque It is usually more rapid than other forms of caries and thus should be detected and treated early

Root caries

Extent of caries Incipient caries Cavitated caries

Incipient caries It is the first evidence of caries activity in the enamel. On smooth surface enamel, the lesion appears opaque white when air-dried, and will seem to disappear (not be distinguishable from contiguous unaffected enamel) if wetted

Incipient caries This lesion of demineralized enamel has not extended to the DEJ and the enamel surface is fairly hard and still intact (smooth to the touch)

Cavitated caries In cavitated caries, enamel is broken and usually the lesion has advanced into dentin Remineralization is not possible and treatment by tooth preparation & restoration is often indicated

Rate Acute Chronic

Acute caries Acute caries, often termed rampant caries, is when the disease is rapid in damaging the tooth It is usually in the form of many, soft light-colored lesions in a mouth and is infectious Less time for extrinsic pigmentation explains the lighter coloration

Rampant caries

Chronic caries Chronic caries is slow, or it may be arrested following several active Phases The slow rate results from periods when demineralized tooth structure is almost remineralized (the disease is episodic over time because of changes in the oral environment) The slow rate of caries allows time for extrinsic pigmentation An arrested enamel lesion is brown-to-black, hard, and as a result of fluoride, may be more caries-resistant than contiguous,unaffected enamel

Arrested caries

Minimizing caries risk

Reducing plaque By reducing the amount of plaque in mouth by Brushing Flossing Mouth rinsing

No between – meal snacks One can reduce the amount of tooth-damaging acid in mouth by eating sugary or starchy foods less often during the day Mouth remains acidic for several hours after eating. Therefore, one is more likely to prevent caries if he avoids between-meal snacks

Use of Dairy product/nuts Use of following items maintains alkalinity of saliva Unsugared milk Cheese Nuts

Chewing gums Chewing gum that contains xylitol helps to decrease bacterial growth. The bacteria cannot use the xylitol as a food source, like sugar

Fluoridated dentifrice Use of fluoride containing tooth paste and mouth washes also helps in controlling caries

Fissure sealing Use of sealants in molar and premolar can save them from plaque accumulation; thus prevents caries

Untreated caries If remained untreated, caries involves the pulp of the tooth which initially becomes reversibly inflamed and finally irreversible condition of pulp takes place. This cause pain, difficulty in chewing and abscess formation

Removal of caries Caries is mechanically removed using hand and rotary instruments and a retentive cavity is prepared to retain restorative material

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