Dental and Restorative Materials Review

Vocabulary practice flashcards covering dental restorative materials including composite resins, varnishes, liners, bases, and dental amalgam based on study notes.

Nanohybrid Composite

A composite restorative material consisting of a combination of conventional/hybrid-sized filler particles with nanosized filler particles, typically called a universal composite.

Polymerization Shrinkage

The reduction in volume that occurs as resin matrix cures, which is minimized by increasing filler particle content.

Nanocomposite

A composite material consisting of nanoscale filler particles and/or nanoclusters dispersed throughout the resin matrix, providing polishability and esthetics.

Abfraction

A wedge-shaped cervical tooth defect associated with stress and flexure from occlusal forces.

Toothbrush Abrasion

Mechanical wear on tooth structure caused by repeated brushing, especially with excessive force and/or abrasive toothpaste.

Pit and Fissure Sealants

Materials designed to flow into and seal pits and fissures on susceptible tooth surfaces, blocking plaque and bacteria to help prevent occlusal caries.

Incremental Placement

The technique of placing composite in small layers and curing each increment to ensure adequate curing and reduce polymerization shrinkage and shrinkage stress.

Resin Matrix

The organic polymer phase that surrounds and binds filler particles in a composite restoration, providing workable consistency before curing.

Filler Particles

Inorganic particles such as silica, quartz, glass, or ceramic added to the resin matrix to improve strength, wear resistance, stiffness, radiopacity, and reduce shrinkage.

BPA (Bisphenol A)

A compound in resin materials that raises health concerns due to its endocrine-disrupting activity and potential temporary leaching of unreacted monomers.

Chemical-cure Composite

A self-cured composite that sets through a chemical reaction after mixing, providing limited working time for the operator.

Light-cured Composite

The most common type of composite, which provides essentially unlimited working time until the material is exposed to a curing light.

Dual-cured Composite

A composite that utilizes both a chemical curing reaction and a curing light, allowing initial light set and self-curing in areas light cannot penetrate.

Cavity Varnish (Copalite)

A thin protective and sealing layer painted onto prepared dentin under an amalgam filling to reduce dentinal fluid movement, postoperative sensitivity, and microleakage.

Microleakage

The microscopic passage of fluids, bacteria, ions, or other substances between the tooth structure and the restorative material.

Calcium Hydroxide (Dycal)

A liner material near the pulp with a high alkaline pH and antibacterial properties that stimulates reparative dentin formation.

Indirect Pulp Cap

A pulp protection procedure used when the pulp is not exposed, placing a protective material over very deep or remaining affected dentin.

Direct Pulp Cap

A pulp protection procedure used when the pulp is exposed, placing material directly over the exposure to encourage healing and hard-tissue formation.

Base

A thicker material placed in deep cavity preparations to replace missing dentin and provide thermal and chemical insulation under a final restoration.

Eugenol

A soothing agent found in zinc-oxide eugenol materials that has a sedative effect on the pulp but can inhibit the polymerization of resin-based composites and adhesives.

Post and Core

A restorative structure where a post is placed inside the root canal space and a core is built around it to replace missing coronal structure and provide support for a crown.

Dental Amalgam

A restorative material made by combining liquid elemental mercury with an alloy powder composed mainly of silver and tin, alongside copper and sometimes zinc.

Copper (in Amalgam)

An alloy component added to amalgam to increase strength, lessen brittleness, and reduce the weak, corrosion-prone gamma-2 phase.

Zinc (in Amalgam)

An alloy element added to amalgam to inhibit oxidation and corrosion, which can cause delayed expansion if contaminated with moisture during placement.

Amalgamation

The reaction and mixing process of combining powdered alloy with liquid elemental mercury to form dental amalgam.

Tarnish

Surface discoloration or loss of luster on a restoration that does not involve deterioration of the underlying material.

Corrosion

Chemical or electrochemical deterioration of a material that weakens the restoration and contributes to marginal breakdown.

Undertrituration

Inadequate mixing of amalgam that produces a dry, dull, crumbly mix with poor physical properties and a weak structure.

Overtrituration

Excessive mixing of amalgam that produces a hot, shiny, soupy, or sticky mix with shortened working time and higher contraction.

Tofflemire Matrix and Wedge

A combination where the matrix replaces a missing proximal wall to hold setting material, and the wedge seals the gingival margin to avoid overhangs while creating space for a contact.

Amalgam Tattoo

A localized blue-gray or black discoloration of the oral mucosa resulting from the implantation of amalgam particles into soft tissue.

Ultimate Strength of Amalgam

The state of physical setting that requires approximately $24\,\text{hours}$ to develop most of the clinically important strength of the material.