dental waxes

Question 1

Thermoplastic materials that are composed of a mixture of components from natural and synthetic sources

Answer 1

DENTAL WAXES

Question 2

Composition of dental waxes
Primary components:

Answer 2

1. Synthetic waxes
2. Natural waxes

Question 3

*40% -60%
*derived from high-boiling fractions of petroleum
*__ wax is likely to flake when it is trimmed, and it does not produce a smooth, glossy surface.

Answer 3

Paraffin wax

Question 4

Natural resin
Added to the paraffin to improve the smoothness and luster, increases toughness and resistance to cracking and flaking.

Answer 4

Gum dammar / dammar resin

Question 5

derived from the fronds of carnauba palm trees
very hard and it has a relatively high melting point
combined with the paraffin to decrease flow at mouth temperature
contributes greater glossiness to the wax surface than dammar resin

Answer 5

Carnauba wax

Question 6

added partially or entirely replace carnauba wax
provides the same general qualities as carnauba wax but its melting point is lower and it is not as hard as carnauba wax

Answer 6

Candelilla wax

Question 7

White wax extracted from ozokerite mineral (colorless or white when pure, but it has a somewhat unpleasant odor)
may replace part of the paraffin to modify the toughness and carving characteristics of the wax.

Answer 7

Ceresin

Question 8

Derived from secretions that bees use to build honeycombs
Reduces brittleness

Answer 8

Beeswax

Question 9

Gums – harden in air and form sticky, viscous liquid with water
Fats – tasteless, odorless and colorless. Increase melting range and hardness
Oils – soften and improve polishability
Natural resin – Rosin (tree/plant exudates), Shellac (produce by insects) – Harden
natural waxes

Answer 9

Gums, fats, resins

Question 10

Important Properties of Waxes(M.F.E.T.)

Answer 10

Melting Range
Flow
Excess Residue
Thermal Expansion

Question 11

→range of temperatures at which each component of wax will start to soften and then flow
❖Usually, the operator does not want the wax to flow but only to soften
❖wax is unstable →operator must be careful to prevent its distortion
❖to prevent distortion →melting range must be higher than the temperature of the environment (especially in hot climates)

Answer 11

Melting Range

Question 12

❖Movement of wax as molecules slip over each other
❖Dependent on temperature and time
❖as temperature increases, the viscosity of the wax decreases until wax becomes a liquid →flow
❖wax capable of flowing at room temperature →difficult to control

Answer 12

FLOW

Question 13

❖It is important that all wax be removed from the object into which it is melted
❖If __ remains after wax is removed, this may result in inaccuracies in the object being produced

Answer 13

EXCESS RESIDUE

Question 14

➢Waxes expand when heated and contract when cooled

The _____ of waxes is greater than that of any other dental material

→If heated above melting range or heated unevenly →expansion above acceptable standards will result

Answer 14

THERMAL EXPANSION

Question 15

Classification of Waxes

Answer 15

1.Pattern waxes
2.Processing waxes
3.Impression waxes

Question 16

are used to create a model of a dental restoration such as a crown or partial denture that eventually is cast using the lost-wax technique
→important properties: low thermal expansion, complete removal of excess residue and appropriate melting ranges
3 types: ?

Answer 16

PATTERN WAXES
1.Inlay Wax
2.Casting Wax
3.Baseplate Wax

Question 17

→Used to produce patterns for metal casting through
the lost wax technique
→Labeled hard, medium and soft (melting range)
→Red, yellow, blue, green
→paraffin, carnauba, ceresin, beeswax

Answer 17

INLAY WAX

Question 18

→Used to construct the metal framework of partial and complete dentures
→Physical properties similar to inlay waxes with the exception of melting range because not softened in the mouth(lab procedures only)

Answer 18

CASTING WAX

Question 19

→Sheets of wax that are generally pink in color
→7.5 cm wide x 15 cm long
→usually layered to produce the contours of the denture and hold the position on which denture teeth are set
→Wax must not distort at mouth temperatures

Answer 19

BASEPLATE WAX

Question 20

→Used primarily to aid in dental procedures both clinically and in the laboratory
3 types:

Answer 20

PROCESSING WAXES
1.Boxing wax
2.Utility wax
3.Sticky wax

Question 21

→Used to form the base portion of a gypsum model
→4-5cm wide red strip of boxing wax is wrapped around an impression to produce a form into which gypsum is poured
→Easily manipulated at room temperature

Answer 21

BOXING WAX

Question 22

→Periphery wax
→Comes in long ropes that are easily manipulated at room temperature
→Used to adapt the periphery of the impression tray to customize the tray and aid in patient comfort
→Given to orthodontic patients to cover sharp brackets and wires

Answer 22

UTILITY WAX

Question 23

→Thermoplastic materials used to obtain impressions of the oral structures
2 types?

Answer 23

. IMPRESSION WAXES
1.Corrective Impression Wax
2.Bite Registration Wax

Question 24

*used as a wax veneer over an original impression to register the detail of soft tissues in a functional state
*Correct errors of impression from lab

Answer 24

CORRECTIVE IMPRESSION WAX