Periodontal Biology and Histology Practice Cards

A comprehensive set of vocabulary flashcards covering the histology, biology, and development of periodontal structures, including bone, collagen, gingiva, PDL, and cementum, based on lecture notes.

Osteoclasts

Large multinucleated giant cells derived from monocytes or hematopoietic stem cells.

Canaliculi

Fine channels through which the dendritic processes of osteocytes communicate.

Mature Osteoclast

A bone-resorbing cell characterized by having multiple nuclei and a clear zone.

Fenestrations

Bone defects most often found on the maxillary first molars.

Reversal Phase

The phase of bone resorption/remodeling during which osteoblast precursors appear.

Haversian System

The functional unit of bone made up of concentric layers of lamellae.

Volkmann's Canals

Channels that connect haversian systems with each other.

Osteoblasts

Cells derived from mesoderm or pericytes that are responsible for bone synthesis.

Ruffled Border

An interface with acid hydrolases formed by an actively resorbing osteoclast.

Lacunae

Small cavities in which osteocytes reside.

Bundle Bone

Bone containing Sharpey's fibers, radiographically corresponding to the lamina dura.

Alveolar Bone Extracellular Matrix

Consists of approximately $65\%$ inorganic material.

Chondroitin-4-sulfate

The predominant glycosaminoglycan found in human alveolar bone.

Hydroxyproline

The amino acid used to determine the amount of collagen in a tissue and which plays a key role in stabilizing the collagen triple helix.

Glycine

The amino acid that constitutes approximately one third ($\frac{1}{3}$) of all amino acids present in collagen.

Type VII Collagen

A non-fibrillar collagen that forms anchoring fibrils linking the basal surface of epithelial cells to type I and III collagen.

Type IV Collagen

A non-fibrillar collagen type that is the main constituent of the basement membrane and lamina densa.

Lysyl Oxidase

The enzyme that catalyzes the crosslinking of multiple collagen strands.

Dental Follicle

The ectomesenchymal tissue that serves as the formative organ for the supporting structures of the tooth.

Hertwig's Epithelial Root Sheath

A structure derived from the inner and outer enamel epithelium that directs root formation.

Cell Rests of Malassez

Discrete clusters of epithelial cells remaining after the fragmentation of Hertwig's epithelial root sheath.

Lamina Propria

The primary component of a "thick" free gingival graft (FGG).

Keratinocyte

The principal cell type of the gingival oral epithelium.

Langerhans Cell

A gingival cell characterized by the presence of Birbeck's granules.

Krause-type End Bulbs

Nerve endings responsible for temperature sensation in the gingiva.

Dermatan Sulfate

The major glycosaminoglycan (GAG) found in gingival connective tissue.

Junctional Epithelium

A stratified squamous non-keratinized epithelium derived from the reduced enamel epithelium.

Hemidesmosomes

Cell junctions that anchor the junctional epithelium to the tooth surface or epithelial intermediate filaments to the basal lamina.

Stratum Basale

The epithelial cell layer where proliferation of gingival cells occurs and where melanocytes are located.

Odland Bodies

Granules whose function is associated with the process of keratinization.

Macula Adherens

The most common intercellular junction in the gingiva, also known as a desmosome.

Ectomesenchyme

The tissue from which periodontal ligament (PDL) fibroblasts originate.

Ruffini Corpuscles

Slowly adapting mechanoreceptors in the PDL that detect low-frequency vibration.

Oxytalan Fibers

The most abundant elastic fibers found in the periodontal ligament, located between collagen fiber bundles.

Cementum Hydroxyapatite

The principal inorganic component of cementum, making up approximately $50\%$ of its content.

Acellular Extrinsic Fiber Cementum

The first type of cementum to form during root development, playing a major role in tooth anchorage.