This document summarizes different types of dental restorative materials including direct esthetic materials like composite and dental amalgam. It discusses the composition, advantages, and disadvantages of each. Composite is generally used for anterior teeth and has replaced silicate cement and acrylic resin due to its tooth-colored appearance. Dental amalgam is an alloy of silver, tin, and mercury that is durable but gray colored. It has been used for over 150 years but there are concerns about possible mercury toxicity, especially with larger fillings. Glass ionomer filling is recommended for children's teeth.

1. Lecture 1
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DENTAL RESTORATIVE MATERIAL
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2. Dental restorative material
*Direct esthetic restorative material
“composite”.
*Dental amalgam.
*Glass ionomer filling. “for children”
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3. Direct esthetic restorative materials
Historically:
1-Silicate cement. 2-Acrylic resin.
3-composite. 4-glass ionomers.
1- Silicate cement:
*Rarely used as a restorative material today.
*Silicate cement powder is composed of acid-
soluble glass, and liquid contains phosphoric acid,
water, and buffering agents.
*The material did not adhere to the tooth structure
and cause pulp irritation.
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4. 2-Acrylic resin:
*Self-curing for anterior restorations.
*The material was disappointing because:
-poor activator system. -high polymerization
shrinkage. -high coefficient of thermal
expansion. -pulp injury. -color change.
-excessive were.
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5. 3- Composite restorations:
*Generally for anterior teeth, also for posterior
teeth but amalgam is still preferred.
*Are presently the most popular tooth colored
materials having completely replaced silicate
cement and acrylic resin.
Composition of composite:
-Organic__ resin matrix “bis-GMA”.
-Inorganic__ filler “silica, quartz, ceramic”.
-Coupling agents___ “silan coupling agent”.
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7. Classification of composite:
*Macrofilled composite:
_Difficult to polish.
_Stronger than composites with smaller particles.
*Microfilled composite:
_Volume of filler is 35-50%
_Lower physical properties, better polish ability.
*Hybrid composite:
_Mixture of macro and microfillers, 75-80%.
_High polish ability and strength can be used for
anterior and posterior restoration.
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8. *Micro-hybrid composite:
_The most polished and with time the surface will
be more polished.
_Weak and cannot use in stress area.
*Packable composite:
_Highly viscous.
_Has low shrinkage.
*Flowable composite:
_Low viscosity. _Delivered into cavity using a syring
_Weaker and wear more compared to hybrids.
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9. Polymerization techniques
*chemical cure “self-cure”:
2-paste system: Base and catalyst.
*light cure:
_Started with UV light to create free radicals, it
cause burns and eye damage.
_Blue light (400-500 nm) is used instead.
_Protection is needed for eye.
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11. *Dual cure:
Light starts the polymerization and the chemical reaction
continues in areas were light cannot reach them.
Clinical steeps
_The etching-acid (liquid or gel) is applied to the
appropriate surfaces to be bond for 15-30 seconds
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12. _The area is then rinsed with water for 5 seconds.
_The area should be dried with air-water syringe.
_Dried etched enamel should exhibit lightly
frosted appearance.
_Bonding procedure___ bonding material applied
to etched surface with specific brush and use light
cure for 20-40 seconds, this step to make the
composite adhere to the tooth surface.
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13. _select the match color of composite and do layer
by layer to full the cavity, the layer not more than
2mm and light curing for each layer.
_finally finishing and polishing the restoration.
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14. DENTAL AMALGAM
Amalgam restoration:
Is an alloy made by mixing mercury with a silver-
tin dental amalgam alloy (Ag-Sn) used as
restoration for more than 150 years.
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15. Amalgam capsule:
*Powdered amalgam alloy
_ Silver and small amount of copper, tin, and zinc.
*Liquid mercury 50%.
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16. Mixing (Triturating)the amalgam material:
Mixed powder and liquid components to achieve
adaptable mass.
The mixing done by amalgamator times vary from
5- 20 seconds.
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17. Types of dental amalgam:
_Copper amalgam ( no longer used ).
_Conventional amalgam ( low-copper )
formulation standardized in 1890.
_High copper amalgam>> first developed in the
1960.
*ADVANTAGES:
_Durable: long lasting.
_Wears well: holds up well to the forces of biting.
_Relatively inexpensive.
_Self-sealing: minimal-to-no shrinkage and resist
leakage.
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18. _Resistance to further decay is high but can be
difficult to find in early stage.
_Frequency of repair and replacement is low.
*DISADVANTAGE:
_Gray colored , not tooth colored.
_May darken, may stain teeth over time.
_Requires removal of some healthy teeth.
_In larger amalgam filling the remaining tooth
may weaken and fracture.
_Because metal can conduct hot and cold
temperature may cause sensitivity to hot and
cold.
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19. _Contact with other metal may cause occasionally
minute electrical flow.
_Concern about possible mercury toxicity.
Mercury toxicity:
The research chow there is no dangerous of
amalgam restoration and in patient mouth don’t
exceed 5 teeth restored by amalgam.
In some cases may cause sensitivity from
mercury.
Is important to condense the amalgam to
express excess mercury-rich matrix.
(right) (left)
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20. Lower lip.
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