Chapter 5

Question 1

Definition of bond or bonding

Answer 1

to connect or fasten; to bind. Items are jointed together at the surface in three main ways: mechanical adhesion, chemical adhesion, combination of the two

Question 2

Definition of adhesion

Answer 2

the act of sticking two things together; describe the bonding or cementation process.

Question 3

Definition of chemical adhesion

Answer 3

atoms or molecules of dissimilar substances bond together

Question 4

Definition of cohesion

Answer 4

attraction among atoms and molecules of like (similar) materials holds them together

Question 5

Definition of etching or conditioning

Answer 5

terms used interchangeably to describe the process of preparing the surface of a tooth or restoration for bonding. most common etching material (etchant) is phosphoric acid

Question 6

Definition of cure or polymerization

Answer 6

a reaction that links low molecular weight resin molecules (monomers) together into high molecular weight chains (polymers) that harden or set.
can be initiated by strictly a chemical reaction (self-cure), light in the blue wave spectrum (light cure), or by a combination of two (dual cure), or heat

Question 7

Definition of wetting

Answer 7

ability of a liquid to wet or intimately contact a solid surface.

Question 8

Definition of wet dentin bonding

Answer 8

bonding to dentin that is kept moist after acid etching to facilitate penetration of bonding resins into etched dentin

Question 9

Definition of smear layer

Answer 9

tenacious layer of debris on the dentin surface resulting from cutting the tooth during cavity preparation

Question 10

Definition of bonding agent

Answer 10

low-viscosity resin that penetrates porosities and irregularities in the surface of the tooth or restoration created by acid etching for the purpose of facilitating bonding

Question 11

Definition of hydrophilic

Answer 11

allows a material to tolerate the presence of moisture

Question 12

Definition of hydrophobic

Answer 12

does not allow a material to tolerate or perform well in the presence of moisture

Question 13

Definition of total etch system

Answer 13

bonding system that includes etching of both enamel and dentin as a separate step from the application of binding agents

Question 14

Definition of self-etch system

Answer 14

bonding system that does not use a separate etching procedure with phosphoric acid. no rinsing needed

Question 15

Definition of hybrid layer

Answer 15

resin/dentin layer formed by intermixing of the dentin bonding agent with collagen fibrils exposed by acid etching. serves as an excellent resin-rich layer onto which the restorative material can be bonded

Question 16

Definition of microleakage

Answer 16

leakage of fluid in the microscopic gap of the restoration margin as a result of differences in expansion and contraction rates of the tooth and the restoration with temperature changes

Question 17

Definition of percolation

Answer 17

movement of fluid in the microscopic gap of the restoration margin as a result of differences in expansion and contraction rates of the tooth and the restoration with temperature changes

Question 18

Definition of hydrodynamic theory of tooth sensitivity

Answer 18

pain caused by movement of pulpal fluid in open (unsealed) dentinal tubules.

Question 19

Definition of contamination

Answer 19

contact with a substance that changes the chemical or mechanical properties

Question 20

What is preparation of the tooth surface?

Answer 20

removing plaque and debris, then etching or conditioning the enamel or dentin with an acid

Question 21

What is the most commonly used acid?

Answer 21

phosphoric acid ranging from 10% - 38%

Question 22

What does acid do?

Answer 22

removes mineral from the surface to create roughness or microscopic porosity

Question 23

What happens when a resin bonding agent or primer is hardened?

Answer 23

cures or polymerizes which creates projections called resin tags that lock into the tooth creating a mechanical bond called micro mechanical retention

Question 24

True or False

The chemical bond is stronger than a physical bond

Answer 24

True (physical bond called a secondary bond which is a weak interaction between two surfaces )

Question 25

True or False

acid etch increases the ability of liquids to wet the surface of the tooth by creating high surface energy

Answer 25

True (however, high surface can also attract contaminates, so good isolation is important)

Question 26

True or False

Surfaces that are poorly wet will cause beading of liquid

Answer 26

True

Question 27

True or False

Bonding agents are usually not very viscous (thick) so they will flow readily and wet the etch surface

Answer 27

True

Question 28

Most bond tests pull the bonded materials apart (tensile strength) or apply forces at approximately 90 degrees to the interface, until the bond fails (sheer bond strength)

Answer 28

True

Question 29

What is the value for the bond strength?

Answer 29

megaPascals (1 mPa = 150 psi)

Question 30

Bonding to enamel usually achieves how many mPa?

Answer 30

30 (4500 psi)

Question 31

How long is the enamel of permeant teeth usually etched for?

Answer 31

20 - 30 seconds with 37% phosphoric acid

Question 32

What is the mineral component of enamel?

Answer 32

hydroxyapatite

Question 33

What is the smear layer composed of?

Answer 33

cut tooth structure, plaque, bacteria, pellicle, saliva, blood
2 micrometers thick

Question 34

True or False

Over-etching will expose too much collagen matrix, causing it to act as a thick barrier and making it more difficult to coat the dentin with bonding agents

Answer 34

True

Question 35

True or False

The dentin surface must be kept moist to keep collagen fibrils fluffed up

Answer 35

True (if over-dried collagen fibrils collapse and form a dense surface that occludes tubules and blocks dentin bonding resins)

Question 36

If enamel becomes contaminated after etching, how long must it be re-etched for?

Answer 36

10-15 seconds before bonding process is continued

Question 37

What are solvents primarily made of?

Answer 37

acetone, ethanol, combination of ethanol and water