PMDC NLE Dental key terms

The hardest, most mineralized tissue of the body, forming the outer protective layer of the tooth crown. It is acellular, cannot regenerate, and consists mainly of hydroxyapatite crystals arranged in rods called prisms.

The yellowish, tubular hard tissue beneath enamel and cementum that makes up most of the tooth. It is less mineralized than enamel, contains odontoblast processes in tubules, and remains sensitive to stimuli when exposed.

The soft connective tissue occupying the pulp chamber and root canals, containing blood vessels, nerves, and odontoblasts. It nourishes the tooth, forms dentin, and mediates pain sensation through its rich innervation.

A thin, bone-like mineralized tissue covering the tooth root surface. It anchors periodontal ligament fibers and thickens with age or function, contributing to tooth support.

The fibrous connective tissue occupying the space between the tooth root and alveolar bone. It attaches the tooth to bone, absorbs occlusal forces, and provides proprioceptive feedback during chewing.

The part of the maxilla or mandible that surrounds and supports the tooth roots. It forms the tooth socket and undergoes resorption when teeth are lost or when periodontal inflammation persists.

A multifactorial, biofilm-mediated disease in which acid from bacterial fermentation of sugars demineralizes tooth hard tissues, producing cavities. It progresses from enamel to dentin and may reach the pulp.

A cariogenic oral bacterium that adheres to tooth surfaces, produces acid from dietary sugars, and synthesizes glucans from sucrose, promoting dental plaque formation and caries initiation.

A structured biofilm of bacteria, salivary proteins, and extracellular polysaccharides adhering to tooth surfaces and restorations. Maturation of plaque increases cariogenic and periodontal pathogenicity.

Mineralized dental plaque that forms hard deposits on teeth and restorations, especially near salivary duct openings. Its rough surface retains plaque and complicates oral hygiene, contributing to periodontal disease.

Reversible inflammation of the gingiva caused by plaque accumulation, characterized by redness, swelling, and bleeding on probing without attachment loss. It can be resolved by removing the bacterial deposits.

A chronic inflammatory disease of the tooth-supporting tissues initiated by plaque bacteria, causing progressive attachment loss, periodontal pocket formation, and alveolar bone destruction that may lead to tooth loss.

A pathologically deepened gingival sulcus caused by apical migration of the junctional epithelium and attachment loss. Its depth and bleeding on probing are key indicators of periodontal disease severity.

Inflammation of the dental pulp, often due to caries or trauma. It may be reversible, with sharp pain to stimuli, or irreversible, with spontaneous or lingering pain that usually requires root canal treatment.

A procedure that removes inflamed or infected pulp tissue, cleans and shapes the root canal system, and seals it with filling material to retain a tooth that would otherwise require extraction.

Inflammation around the root apex, usually caused by infection spreading from a necrotic pulp through the root canal system. It may present as a periapical radiolucency and cause pain on biting.

A collection of pus at the root apex resulting from pulpal infection extending into periapical tissues. It causes severe pain, tenderness, swelling, and sometimes systemic signs requiring drainage and antibiotic therapy.

A mineral that strengthens enamel by forming fluorapatite, promotes remineralization, and inhibits bacterial acid production. It is delivered through water, toothpaste, varnish, and professional applications to prevent caries.

The principal calcium phosphate mineral of enamel, dentin, and bone. Its dissolution by bacterial acid is the chemical basis of dental caries, and its replacement by fluorapatite increases acid resistance.

Sharp, brief pain from exposed dentin in response to thermal, evaporative, tactile, or osmotic stimuli that cannot be explained by another dental defect. It is explained largely by fluid movement within dentinal tubules.

A deviation from normal occlusion involving misalignment of teeth or improper relationship of the dental arches. It is classified by Angle's system and may require orthodontic treatment.

A system that classifies occlusion by the relationship of the first molars, defining Class I as normal, Class II as mandibular retrusion, and Class III as mandibular protrusion. It guides orthodontic diagnosis and treatment planning.

The horizontal distance between the incisal edges of the maxillary and mandibular central incisors. Increased overjet may increase trauma risk and is a key measurement in orthodontic assessment.

The vertical overlap of the maxillary incisors over the mandibular incisors. Deep overbite may cause palatal trauma or temporomandibular problems and is corrected during orthodontic treatment.

A tooth that fails to erupt into its normal position within the expected time, often due to lack of space, obstruction, or abnormal angulation. Third molars and canines are most commonly affected.

The removal of a tooth from its socket, indicated for severe caries, periodontal disease, trauma, impaction, or orthodontic reasons. It requires adequate anesthesia and attention to hemostasis and socket healing.

Alveolar osteitis occurring after extraction when the blood clot is lost or disintegrates, exposing bone. It causes severe throbbing pain a few days after extraction and is managed by socket irrigation and dressing.

Reversible loss of sensation in a specific region produced by drugs such as lidocaine, used to control pain during dental procedures. It may be delivered by infiltration or nerve block techniques.

The use of X-rays to image teeth and supporting structures, including periapical, bitewing, and panoramic views. It aids diagnosis of caries, periodontal bone loss, and impacted teeth while requiring radiation protection.

A clinical examination using a calibrated probe to measure sulcus or pocket depth and detect bleeding and attachment loss. It is essential for diagnosing and monitoring periodontal disease.

The removal of plaque and calculus from tooth surfaces, especially below the gumline, using hand instruments or ultrasonic devices. It is a cornerstone of periodontal therapy and prevention.

Patient education on brushing, flossing, and other self-care methods to remove plaque and prevent caries and periodontal disease. It is tailored to individual needs and reinforced at each visit.

A restorative material made by mixing silver alloy powder with mercury, used for posterior restorations. It is strong and durable but requires sound tooth structure and careful handling of mercury.

A tooth-colored restorative material of resin matrix and filler particles, bonded to enamel and dentin. It is used for esthetic restorations and requires isolation and proper light curing.

A titanium fixture surgically placed in the jawbone to support a crown, bridge, or denture through osseointegration. Success depends on adequate bone volume and good oral hygiene.

The direct structural and functional connection between living bone and the surface of a load-bearing implant without intervening soft tissue. It is the biological basis for implant stability and success.

A malignant neoplasm of the oral cavity, most often squamous cell carcinoma, associated with tobacco, alcohol, and betel quid use. Early detection through oral examination greatly improves outcomes.

Measures such as hand hygiene, personal protective equipment, sterilization, and safe sharps handling that prevent transmission of pathogens in dental practice. It protects both patients and dental staff.