Dental Materials NBDHE Exam | Actual Questions and Answers
Latest Updated 2026/2027 (Graded A+)
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Adhesion
- ✔✔The chemical attraction between unlike molecules
•
Cohesion
- ✔✔The chemical attraction between like molecules
•
Coefficient of thermal expansion
- ✔✔An index which indicated how one material reacts to temperature extremes in relation
to another
•
Compressive Strength
- ✔✔The force at which a material breaks under pressure
•
Creep
- ✔✔Slow dimensional change caused by compression
•
Ductility
- ✔✔The ability to undergo change of form without breaking
•
Elasticity
- ✔✔Material's ability to recover its initial shape after undergoing a force
•
Galvanism
- ✔✔An electrical current generated by dissimilar metals in an acidic environment
•
Gelation
- ✔✔The process of gelling (solidification by cold)
•
Imbibition
- ✔✔Absorption of a solvent by a gel
•
Malleability
, - ✔✔A material's capacity to be shaped by force or pressure
•
Microleakage (percolation)
- ✔✔Passage of oral fluids/bacteria into and out of tooth structure due to marginal gap or
failure of marginal (restorative) seal
•
Polymerization
- ✔✔The linking, branching, or cross-linking of smaller molecules
•
Proportional limit
- ✔✔The force at which a material cannot return to its original shape
•
Syneresis
- ✔✔Contraction of a gel due to the loss of a solvent
•
Tensile strength
- ✔✔The force needed to stretch a material to the point of fracture
•
Viscocity
- ✔✔Resistance to flow
•
Amalgam
i. - ✔✔By definition: an alloy of mercury
ii. In dentistry: an alloy of mercury with silver, copper, tin, and zinc
iii. Silver, a base metal, susceptible to corrosion
iv. Copper added to minimize the corrosion (gamma II phase eliminated)
•
Amalgam desirable features
i. - ✔✔Durable
ii. Similar compressive strength to enamel
iii. Relatively inexpensive
•
Amalgam undesirable features
i. - ✔✔Unattractive
ii. High thermal conductivity
iii. Dimensionally unstable (creep)
Latest Updated 2026/2027 (Graded A+)
•
Adhesion
- ✔✔The chemical attraction between unlike molecules
•
Cohesion
- ✔✔The chemical attraction between like molecules
•
Coefficient of thermal expansion
- ✔✔An index which indicated how one material reacts to temperature extremes in relation
to another
•
Compressive Strength
- ✔✔The force at which a material breaks under pressure
•
Creep
- ✔✔Slow dimensional change caused by compression
•
Ductility
- ✔✔The ability to undergo change of form without breaking
•
Elasticity
- ✔✔Material's ability to recover its initial shape after undergoing a force
•
Galvanism
- ✔✔An electrical current generated by dissimilar metals in an acidic environment
•
Gelation
- ✔✔The process of gelling (solidification by cold)
•
Imbibition
- ✔✔Absorption of a solvent by a gel
•
Malleability
, - ✔✔A material's capacity to be shaped by force or pressure
•
Microleakage (percolation)
- ✔✔Passage of oral fluids/bacteria into and out of tooth structure due to marginal gap or
failure of marginal (restorative) seal
•
Polymerization
- ✔✔The linking, branching, or cross-linking of smaller molecules
•
Proportional limit
- ✔✔The force at which a material cannot return to its original shape
•
Syneresis
- ✔✔Contraction of a gel due to the loss of a solvent
•
Tensile strength
- ✔✔The force needed to stretch a material to the point of fracture
•
Viscocity
- ✔✔Resistance to flow
•
Amalgam
i. - ✔✔By definition: an alloy of mercury
ii. In dentistry: an alloy of mercury with silver, copper, tin, and zinc
iii. Silver, a base metal, susceptible to corrosion
iv. Copper added to minimize the corrosion (gamma II phase eliminated)
•
Amalgam desirable features
i. - ✔✔Durable
ii. Similar compressive strength to enamel
iii. Relatively inexpensive
•
Amalgam undesirable features
i. - ✔✔Unattractive
ii. High thermal conductivity
iii. Dimensionally unstable (creep)
