PULPITIS

Pulpitis “ The pulp lives for the dentin and the dentin

lives by the grace of the pulp. Few marriages in nature are marked by a greater affinity.”

Alfred L. Ogilvie

PULP DENTIN COMPLEXThe dental pulp is a soft tissue of

mesenchymal orgin located in the center of a

tooth.

Specialized cells called odontoblasts are

arranged peripherally in direct contact with

the dental matrix.

This close relationship between

ododntoblasts and dentin – pulp dentin

complex.

Odontoblast the multifunctional cell

Pulp is a microcirculatory system containing arterioles and venules

Pulp is unique Surrounded by rigid wallsSusceptible to changes in pressureMinimal collateral blood supplyComposed of simple connective tissueLacks prioprioceptionHighly sensitive

Immune response in pulp

Dendritic cells and macrophages bind to antigen

T and B cells respond to antigens Immune response occurs

Pulp tissue is presented with new antigen

Innate response initiated Followed by specific response

Bacteria enter

Limited blood supply of pulp

Low compliance chamber of pulp

Immune defense

Primarily two mechanisms account for this effect:

(i) The peripherally directed flow of dentinal fluid

(ii) The absorbance of bacteria and bacterial

macromolecules to the inner walls of the tubules

Thereby, dentin is able to temper exposures of

noxious elements to the pulp, allowing it to

adapt and organize an effective immune

defense response.

Non specific immune response

Acids and enzymes of bacteria dissolve enamel and dentin

Permeability increases

Toxins diffuse in to dentinal tubules

Macrophages and neutrophils are activated

Odontoblasts are first cells to be contacted by toxic bacterial broth

Haemodynamic changes of pulp in caries

Blood flow increased in few experiments

Interstitial fluid pressure increases by the movement of fluid from the capillaries to the interstitial space

Neural changes in pulpitisSympathetic activity inhibits odontoclastsAfferent fibers release neuropeptides- substance P, calcitonin gene related peptideVasodilatation and capillary permeability increases with these neuropeptides In injured pulps – Nerve growth factor increasesSprouting of sensory nerve fibers occurs within next day of injury

Neuropeptides are transported via axonal blood flow to nerve terminals in the pulp

Etiology of pulpitisDental cariesTraumatic exposureThermal changesFracture of crown Chemical irritationCracked tooth syndrome

Abott etal 2007

Diseases of pulp( grossman)

PulpitisAcute seriousAcute suppurativeChronic ulcerativeChronic hypertrophicPulp degenerationCalcificFibrousAtrophicfatty

Necrosis or gangrene of pulp

Pulpitis- response to injuryThe severity of the caries determines the fate of the

pulp. (Smith, 2002)  Mild injury such as slowly progressing caries in the

dentin, mild abrasion and erosion, fracture of the enamel and dentin, chemical irritation. (D. Tziafas, 2004)

Up regulation of biosynthetic activity of primary odontoblasts to form tertiary dentin

Extent Of Injury To Pulp

Severe dentinal injury with no exposure of

pulp 

Cases with Rapidly progressive caries

During Cavity preparation

Cytotoxic injury in pulpal cells during restoration. 

Dead tracts form

Severe injuryA. Odontoblasts under injury site are destroyed

(forming dead tracts).B. Inflammatory-healing cascade occurs.C. Proliferation of pulpal cells into the dentin

surrounding the pulp.D. Fibroblast cells laid down as fibrodentin on

dentin-pulp border.E. If cariogenic environment is removed, new

generation odontoblast-like cells (dentin forming cells) differentiate from pulp to form tubular tertiary dentin.

Symptoms of pulpitisAcute pulpitis Chronic pulpitisNoticeable painWorsened by lying downAcute sensitivity to hot

and coldSeen commonly in

adolscents and children

Less noticeable painFound in adults

REVERSIBLE PULPITIS

The pain is of very short duration and does not linger after the stimulus has been removed.

The tooth is not tender to percussion.The pain may be difficult to localize.The tooth may give an exaggerated responseto vitality tests.The radiographs present with a normal

appearance, and there is no apparent widening of the periodontal ligaments.

IRREVERSIBLE PULPITISThere is often a history of spontaneous bouts of pain

which may last from a few seconds up to several hours.When hot or cold fluids are applied, the pain elicited

will be prolonged. In the later stages, heat will be more significant; cold may relieve the pain.

Pain may radiate initially, but once the peri- odontal ligament has become involved, the patient will be able to locate the tooth.

The tooth becomes tender to percussion once inflammation has spread to the periodontal ligament.

A widened periodontal ligament may be seen on the radiographs in the later stages.

DIFFERENCES Reversible pulpitis Irreversible pulpitisMild- moderate

inflammationNo lingering painSharp pain especially to

coldNo spontaneous painReverses upon removal

of etiology A delta fiber stimulation

Persistent inflammatory condition- noxious stimulus

Rapid onset of painPain is spontaneousExacerbated on bending

or lying downReferred painBoring, throbbing,

severe in later stages