Pathology of the Pulp Tissues

Vocabulary practice flashcards covering the etiology, pathophysiology, diagnostic criteria, classification, clinical symptoms, and histopathology of pulp diseases and inflammation.

Dental pulp

The vascular connective tissue occupying the center of the tooth, composed of living connective tissue and specialized cells called odontoblasts, whose primary function is to form dentin.

Odontoblasts

Specialized pulpal cells situated at the periphery of the pulp adjacent to predentin that form primary, secondary, and reparative dentin, and on whose activity pulp vitality mainly depends.

Pulpitis

Inflammation of the dental pulp tissue, recognized as the most common reason for dental pain.

Five cardinal signs of inflammation

The classic indicators of an acute tissue response—pain, hotness (warmth), redness, swelling, and loss of function—which do not typically manifest in dental pulp due to its containment within rigid dentin walls.

Normal thermal threshold of the pulp

The physiologic temperature range extending from $20\,^{\circ}\text{C}$ to $45\,^{\circ}\text{C}$ within which the pulp responds normally without triggering an inflammatory response.

Thermal pulp hyperemia

An inflammatory pulpal response (pulpitis) provoked by sudden temperature changes that exceed $45\,^{\circ}\text{C}$ (excessive heat) or fall below $20\,^{\circ}\text{C}$ (excessive cold).

Free nerve endings (pulpal pain transmission)

The exclusive sensory receptor type present in the dental pulp; due to the complete lack of proprioceptors and lack of discrete cortical representation, pulpal pain is poorly localized and cannot be pinpointed to the offending tooth.

Anachoresis

The phenomenon whereby bacteria circulating within the bloodstream in systemic infectious diseases (e.g., tonsillitis) tend to localize in areas of inflamed pulp tissue, producing anachoretic pulpitis.

Odonto-iatrogenic pulpitis

Inflammation of the dental pulp caused by operative procedures performed by a dentist (dentist-induced pulpitis, derived from the Greek iatro- meaning physician).

Galvanism (galvanic shock)

An intermittent electrical current that irritates the pulp, generated when two dissimilar metal restorations of differing electromotive potentials (such as gold opposing amalgam) make contact in the oral cavity.

Aerodontalgia

Toothache occurring in aircrew personnel at high altitudes or in decompression chambers where reduced atmospheric pressure below $1\,\text{ATM}$ ($14.7\,\text{lbs/in}^2$) causes trapped gases beneath restorations or fractures to expand.

Electric pulp tester (EPT)

A diagnostic electrical instrument whose tip is applied to sound tooth structure to evaluate sensory pulpal nerve responsiveness and establish vitality thresholds.

Focal reversible pulpitis (pulp hyperemia)

The earliest form of pulpitis, characterized by vascular congestion, engorged capillaries, intact odontoblasts, low-threshold EPT response, and brief, sharp shooting pain triggered by cold that subsides immediately upon stimulus removal.

Acute pulpitis

A persistent, irreversible acute pulpal inflammation characterized by severe, throbbing, lancinating pain exacerbated by heat or lying down, persistent pain after stimulus removal, and pulpal abscess formation.

Partial suppurative pulpitis

An initial stage of acute pulpitis characterized by localized liquefaction necrosis and micro-abscess formation confined to a single pulpal horn.

Total suppurative pulpitis

The end stage of acute suppurative pulpitis wherein multiple liquefactive abscesses coalesce throughout the chamber, converting the entire pulp into necrotic purulent debris.

Chronic closed pulpitis

A chronic pulpal inflammation occurring without open pulp exposure, presenting with dull aching pain, delayed EPT response, reparative dentin formation, and pulpal infiltration by lymphocytes, plasma cells, and granulation tissue.

Granulation tissue

Vascularized connective tissue formed during chronic inflammation and repair, consisting of newly formed fibroblasts, proliferating collagen fibrils, and budding blood vessels.

Sclerotic dentin

Dentin formed by the calcification and progressive obliteration of dentinal tubules in response to low-grade, long-standing irritants such as slow-progressing caries.

Reparative dentin

Tertiary dentin deposited by surviving or replacement odontoblasts at the pulp-dentin junction to seal and protect the pulp from external irritants.

Chronic open ulcerative pulpitis

A chronic inflammatory pulpal condition presenting as an ulcerated surface in a carious tooth with an exposed pulp chamber, showing minimal pain because inflammatory edema drains freely through the open defect.

Chronic open hyperplastic pulpitis (pulp polyp)

An exuberant chronic inflammatory condition in children or young adults with high tissue resistance and wide apices, appearing as a pink or dark red fleshy globular mass of granulation tissue protruding into a large carious cavity.

Epithelialized pulp polyp

A mature chronic hyperplastic pulp polyp surfaced by hyperplastic stratified squamous epithelium derived from desquamated salivary cells or oral mucosa friction, resulting in a pedunculated lesion that bleeds less readily.

Gingival polyp

A hyperplastic overgrowth originating from adjacent interdental gingival papilla growing into a cavity defect, distinguished from a pulp polyp by its gingival attachment, extreme tenderness on probing, and marked bleeding.

Pulp necrosis (pulp gangrene)

The complete death of pulp tissue, leading to an asymptomatic non-vital tooth with no response to electric pulp testing and possible dark crown discoloration from extravasated red blood cells and tissue breakdown.