Oral Pathology - Dental Caries and Plaque

Vocabulary flashcards covering core concepts of dental caries, etiology, microbiology, saliva and fluoride roles, and dental plaque formation based on HPT202 Oral Pathology notes.

Dental Caries

A localized, multifactorial, infectious microbial disease that begins after tooth eruption, resulting in the demineralization of inorganic tooth structure, breakdown of the organic matrix, and cavity formation.

Pit and Fissure Caries

A primary type of dental caries that develops within the deep structural pits and fissures of teeth where food debris and microorganisms readily accumulate.

Smooth Surface Caries

A type of dental caries occurring on the smooth enamel surfaces of teeth, particularly proximal regions below contact areas and cervical margins.

Cemental (Root) Caries

A type of dental caries that develops on exposed root surfaces or cementum, commonly associated with gingival recession and aging.

Recurrent Caries

Dental caries that forms at the margin or beneath existing dental restorations.

Etiological Factors of Dental Caries

The four primary interacting factors required for caries formation: susceptible tooth structure, dental biofilm (microorganisms), fermentable substrate (diet), and sufficient time.

Secretory Immunoglobulin A (sIgA)

An antibody synthesized by plasma cells in salivary glands and secreted in saliva that protects against caries by killing bacteria, inhibiting bacterial metabolic activity, and preventing bacterial adherence to tooth surfaces.

Fluoroapatite

An acid-resistant mineral component formed in enamel when fluoride substitutes for hydroxyl groups in hydroxyapatite crystals.

Dental Fluorosis

Enamel hypoplasia and mottling caused by ingesting water with fluoride concentrations exceeding $1.5\,\text{PPM}$ during tooth mineralization due to its toxic effect on ameloblasts.

Streptococcus mutans

A key acidogenic and aciduric oral bacterium that ferments dietary sucrose into lactic acid and synthesizes extracellular polysaccharides (glucan and fructan) and intracellular amylopectin.

Dextran

A water-insoluble, highly adhesive glucose polymer synthesized from sucrose by Streptococcus mutans using glucosyltransferase, contributing to bulky dental plaque formation.

Levan

A water-soluble, less adhesive fructose polymer synthesized from sucrose by Streptococcus mutans using fructosyltransferase, functioning primarily as a carbohydrate storage matrix.

Pioneer Bacteria

Initial bacterial colonizers of the acquired pellicle within the first 8 hours, predominantly consisting of Streptococcus sanguis, Streptococcus mitis, and Actinomyces viscosus.

Lactobacilli

Weakly cariogenic bacteria that participate in the progression of deep enamel carious lesions and act as pioneer organisms in the advancing caries front of dentin.

Actinomyces viscosus

An oral bacterial species specifically associated with the development of root surface (cemental) caries.

Acquired Enamel Pellicle

A cell-free, structureless film composed of salivary glycoproteins that rapidly deposits onto clean tooth enamel, serving as the foundation for bacterial colonization.

Dental Plaque (Biofilm)

A tenaciously adherent biofilm consisting of dense bacterial communities embedded in an extracellular organic and inorganic matrix on the tooth surface.

Stages of Dental Plaque Formation

The sequential process of biofilm development consisting of acquired enamel pellicle formation, initial community (colonization and growth), intermediate community, mature community, and dispersion phase.

Corn Cobs Aggregation

A distinctive microscopic bacterial pattern found in mature plaque, consisting of a central bacterial filament coated by a dense outer layer of coccal forms.

Plaque Matrix

An extracellular matrix surrounding plaque bacteria that functions as a diffusion limiting membrane, retaining high concentrations of lactic acid while delaying the penetration of salivary buffers.

Stephan's Curve

A graphical representation depicting the rapid drop in dental plaque pH following exposure to fermentable carbohydrates and its subsequent slow recovery toward resting levels.