A. Introduction to Dental Biomaterials

A01    Explain why biocompatibility, mechanical properties, handling characteristics, esthetics and economy must be considered when a dental material is selected.

A02    Describe how matter and energy interact to form different states and structures, and how that interaction affects thermal expansion and stiffness of solids.

A03    Identify the three types of primary bonds, and explain the differences among these three types regarding bond strength, bond direction, and ability to reestablish a broken bond.

A04    Explain the way secondary bonds work, and discuss their ability to reform broken bonds.

A05    Explain why there is a specific interatomic bond distance.

A06    Demonstrate your understanding of the bonding energy curve as a function of the bond distance.

A07    By use of the bonding energy curve, explain phenomena such as thermal expansion and melting point.

A08    Discuss the packing density of the simple cubic, the body-centered cubic, and the face-centered cubic structure, and identify the maximal packing density of these three structures.

A09    Discuss whether a metal can be a "glass."

A10    Discuss the effect of surrounding structure density and charge density on the diffusion properties of a molecule diffusing through the surrounding structure.

A11    If possible, differentiate mechanical and chemical bonding and relate it to an atomic level, and suggest methods to be used to differentiate them.

A12    Discuss the relationship between surface energy, wettability, and contact angle and the effect of these relationships on the bonding between an adhesive and another material.

A13    Discuss and identify three potential problems in bonding a restorative material to tooth structure.

A14    Differentiate chemical and physical properties.

A15    Identify at least one wear mechanism.

A16    Discuss the meaning of a Newtonian fluid.

A17    Dental constructions (e.g., dentures) sometime warp or distort. Explain why they do so.

A18    The terms creep and flow are often used in dentistry. Identify similarities as well as differences between these two terms.

A19    Demonstrate your understanding of value, hue and chroma by discussing the color of a tooth and how it changes under different lighting conditions.

A20    Differentiate between thermal conductivity and thermal diffusivity, and explain why thermal diffusivity may be more important to consider from a dental point of view.

A21    Identify the key mechanical properties that relate to elastic, plastic and a combination of elastic-plastic properties.

A22    Define stress and strain. Identify the main differences regarding how forces are oriented relative to the area in which tensile stress or shear stresses develop.

A23    Demonstrate your understanding of a stress versus strain curve by:

a) identifying elastic limit, proportional limit, yield strength, and modulus of elasticity and

b) defining Hooke’s law and applying it to that portion of the curve where it is valid.

A24    Discriminate between the definitions of the following terms: flexibility, resilience, impact force, permanent deformation, strength, flexure strength, fatigue, impact strength, toughness, brittleness, ductility, malleability, hardness, abrasion resistance, and relaxation.

A25    Compare and contrast the tensile strength, compressive strength, and modulus of elasticity of enamel and dentin.

A26    Discuss the magnitude of loads generated in the oral cavity and how the loads and the surface area over which they are applied are related to the stress generated.

A27    Discuss how a flaw, present in a brittle material, affects tensile and compressive strength of that material.

A28    Discuss the clinical significance of properties such as modulus of elasticity, tensile strength, compressive strength and flexural strength.