Histological and Clinical Features of Dental Caries

Remineralization

Non-cavitated enamel lesions retain most of the original crystalline framework of the enamel rods and they serve as nucleating agents for ???

Remineralized (Arrested) Lesions

Should not be restored unless they are esthetically objectionable

Apex to base

Smooth surface caries in the dentin likewise spreads laterally at the DEJ and narrows down at it reaches the pulp. It has an ???? relationship with the enamel caries

Very Soft

Surface Hardness of Active Caries

Hard

Surface Hardness of Hypocalcified Enamel

Hard

Surface Hardness of Inactive Caries

Softened

Surface Hardness of Noncavitated Caries

Hard

Surface Hardness of Normal Enamel

Cavitated

Surface Texture of Active Caries

Smooth

Surface Texture of Hypocalcified Enamel

Roughened

Surface Texture of Inactive Caries

Smooth

Surface Texture of Noncavitated Caries

Smooth

Surface texture of Normal Enamel

Macdevant

Also named the Five Zones of Dentin and we usually use this one in practice

Remineralization

As long as the pulp tissue is vital, the dentin-pulp complex reacts to caries attack by attempting to initiate ???? and blocking off the open dentinal tubules

Remineralized (Arrested) Lesions

Clinically, ???? can be observed as intact, but discolored, usually brown or black, spots.

Brown or black

Clinically, remineralized (arrested) lesions can be observed as intact, but discolored, usually ????, spots.

Cementum Caries

Clinically, the lesion appears as saucer-shaped cavities and U-shaped in cross sections and progress rapidly because of the lack of enamel covering

Opaque

Hydrated Active Caries looks ?????

Translucent

Hydrated Enamel looks ???

Opaque

Hydrated Hypocalcified Enamel looks ???

Opaque and Dark

Hydrated Inactive Caries looks ???

Translucent

Hydrated Noncavitated Caries looks ????

Odontoblasts

Infected dentin contains a wide-variety of pathogenic materials or irritants, these materials cause the degeneration and death of the ????? and their tubular extensions, and mild inflammation of the pulp

Outer carious dentin

Infected dentin is also known as ????

Remineralize

It has been shown experimentally and clinically that non-cavitated caries of enamel can ????

Pulp

Rapidly advancing caries bringing high acid levels overpowers the dentinal defenses and results in infection, abscess, and death of the ???/

Near Gingiva or are under Proximal Contacts

SMOOTH SURFACE CARIES If cariogenic biofilm attached it is usually ????, which are protected sites for mechanical cleaning from the tongue, cheek movement and toothbrushing.

Cementum Caries

This is usually seen where there is gingival recession and the oral hygiene is poor

Clinical Appearance of Cemental Caries

a. Active root caries b.Arrested root caries lesion

Different Clinical Site for Caries Initiation

>Developmental pits and fissures of enamel, which are the most susceptible sites >Smooth enamel surfaces that shelter cariogenic biofilm >Root surfaces

Basic Structures of Enamel

>Enamel prism or enamel rods, >Prism borders >Striation >Incremental growth bands (Striae of Retzius) >Surface zone

Five Zones of Dentin Caries (Ekstrand)

>Reactive Dentin >Sclerotic Dentin >Zone of Demineralization >Zone of Bacterial Invasion >Peripheral Rod Direction

4 Zones of Caries of Enamel

>Translucent Zone >Dark Zone >Body of Lesion >Surface Zone

Cavitated Enamel Lesions

????? can be initially detected as subtle breakdown of enamel surface

Calcium and Phosphate Ions

????? from saliva can penetrate the enamel surface and precipitate on the highly reactive crystalline surfaces of the enamel lesion

Affected dentin

It has demineralization of the intertubular dentin and initial formation of fine crystals in the tubule lumen. There is damage to the odontoblastic process; no bacteria found (subtransparent zone)

Affected dentin

It is also known as carious inner dentin

False

(TRUE OR FALSE) Usually, caries in pits and fissures spreads in triangular pattern with apex towards DEJ and base towards surface

True

(TRUE OR FALSE) Usually, caries in pits and fissures spreads in triangular pattern with base towards DEJ and apex towards surface

3 Levels of Dentinal reaction to Caries

1. Reaction to long-term, low-level acid demineralization associated with a slowly advancing lesion. 2. Reaction to a moderate-intensity attack 3. Reaction to severe, rapidly advancing caries characterized by very high acid levels

Vital Pulp

3 LEVELS OF DENTINAL REACTION TO CARIES In slowly advancing caries, the ???? can repair demineralized dentin by remineralization of the intertubular dentin and apposition of peritubular dentin

Surface of the lesion

CAVITATED ENAMEL LESIONS Approximately 20-100 um thick; thinner in active lesion and thicker in inactive ones. There is partial demineralization 10% mineral loss. The characteristic feature is the broadening of the prism sheaths.

Dark zone

CAVITATED ENAMEL LESIONS Is immediately above the translucent zone, appears dark exhibits approx. 6% mineral loss per volume of enamel. Shows positive birefringence in polarized light (normal enamel negative birefringence).

Translucent zone

CAVITATED ENAMEL LESIONS Is the advancing front of the caries, the innermost zone

Body of the Lesion

CAVITATED ENAMEL LESIONS Occupies the major portion of the lesion. It is the area of maximum demineralization. It is positively birefringent. This is the largest zone which exhibits enhanced striae of Retzius

Saucer-shaped cavities

CEMENTUM CARRIES Clinically, the lesion appears as ???? and U-shaped in cross sections and progress rapidly because of the lack of enamel covering

U-shaped

CEMENTUM CARRIES Clinically, the lesion appears as saucer-shaped cavities and ???? in cross sections and progress rapidly because of the lack of enamel covering

Infected dentin

Consists of decomposed dentin teeming with bacteria; no recognizable dentin structure and collagen and minerals seem to be absent. Great number of bacteria are dispersed in this granular material and should be removed to prevent spreading the infection zone of destruction

Dentin

Contains much less mineral and possesses microscopic tubules that provide a pathway for the ingress of bacteria and egress of minerals, and so less resistance to acid attack

Normal Dentin

Deepest area which has tubules with ondotoblastic processes and no crystals are in the lumen

Opaque

Desiccated/Dried Active Caries looks ?????

Opaque

Desiccated/Dried Hypocalcified Enamel looks ???

Opaque and Dark

Desiccated/Dried Inactive Caries looks ???

Opaque

Desiccated/Dried Noncavitated Caries looks ????

Translucent

Desiccated/Dried Normal Enamel looks ???

Affected dentin

It is softer than normal dentin; there is further loss of minerals from intertubular dentin, many large crystals are present in the tubule lumen, stimulation produces pain; no bacteria present (translucent zone) capable of self-repair provided the pulp remains vital

Enamel Rods

Lesions starting on smooth surfaces have a broad area of origin and a conical, or pointed extension toward the DEJ. The 'V-shaped" pattern follows the direction of the ???? and are wide on enamel side tapering as it goes into the portion of the dentin, then spreads rapidly laterally and pulpally.

Ekstrand

Named the five zones of dentin caries

White Spot

On a clean, dry teeth, the earliest evidence of caries on the smooth enamel surface of a crown is a ????

Infected Dentin

Outermost zone; Consists of decomposed dentin that is teaming with bacteria. Great number of bacteria is present.

V-shaped lesion

PITS AND FISSURE CARIES (WHAT SHAPE ) The carious lesion follows the path of the enamel rod; hence a characteristic angular ????

Gram positive cocci and S. sanguis

PITS AND FISSURE CARIES ????? are commonly found in pits and fissures of newly erupted teeth. While S. mutans are found in carious pits and fissures.

S. mutans

PITS AND FISSURE CARIES Gram positive cocci, S. sanguis are commonly found in pits and fissures of newly erupted teeth. While ???? are found in carious pits and fissures.

Base to base

Pit and fissure caries rapidly spreads at it reaches the DEJ. It has a ????? relationship with the enamel caries

Smooth Surfaces

Present a less favorable site for cariogenic biofilm attachment

Structural differences

Progression of caries in dentin is different from that of enamel because of the ?????? of dentin

Pits and Fissure Caries

The carious lesion starts on the lateral walls of the fissures that eventually flare laterally at the bottom of the pit.

Lesion

The changes in the structures of Enamel determines the ??????

Normal Dentin

The deepest area of the zone where the tubules with odontoblastic processes are smooth and no crystals are present in the lumens. No bacteria

Actinomyces

The microorganisms involved in root caries are chiefly ????? and they appear to invade the cementum either along Sharpey's fibers or between bundles of fibers comparable to invasion along dentinal tubules.

Sharpey's fibers

The microorganisms involved in root caries are chiefly actinomyces and they appear to invade the cementum either along ???? or between bundles of fibers comparable to invasion along dentinal tubules.

More resistant

The presence of trace amounts of fluoride ions during this remineralization process greatly enhances the precipitation of calcium and phosphate, resulting in the remineralized enamel becoming ?????? to subsequent caries attack because of the incorporation of the more acid-resistant fluorapatite.

Pulp

These materials cause the degeneration and death of the odontoblasts and their tubular extensions, and mild inflammation of the pulp. The ????? then produces replacement odontoblasts and these cells produce reparative dentin on the affected portion of the pulp chamber wall.

Dentin

These materials cause the degeneration and death of the odontoblasts and their tubular extensions, and mild inflammation of the pulp. The pulp then produces replacement odontoblasts and these cells produce reparative ???? on the affected portion of the pulp chamber wall.

Cavitated Enamel Lesions

They are very sensitive to probing and can easily be enlarged by using sharp explorers and excessive probing force.

Inverted V-shape or triangular

WHAT SHAPE Pit and fissure caries on enamel is an ????

Triangle or v-shaped

WHAT SHAPE Smooth surface caries on enamel is ????

Dentino enamel junction (DEJ)

When the carious lesion has penetrated the dentin, it spreads laterally along the ????, undermining the enamel.

V-Shaped

When the carious lesion has penetrated the dentin, it spreads laterally along the dentino enamel junction (DEJ), undermining the enamel. The pattern of invasion is a ???? in cross section with a wide base at the DEJ and the apex directed pulpally.

Dentin

Where caries advances more rapidly

Infected dentin

Zone of bacterial invasion marked by widening and distortion of the dentinal tubules, which are filled with bacteria. cannot remineralize

Turbid Dentin

Zone of bacterial invasion widening and distortion of dentinal tubules, which are filled with bacteria. Very little mineral present and collagen in this zone is irreversibly denatured

Transparent Dentin

Zone of carious dentin that is softer than normal dentin, further loss of minerals from intertubular dentin, many large crystals are present in tubule lumen. Stimulation of this region produces pain. No bacteria present.

Sub-transparent Dentin

Zone of demineralization of intertubular dentin initial formation of very fine crystals, damage to odotoblast process is evident, no bacteria found.