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By
Prof.Dr/Mona Hussein
The science of dental biomaterials
involves the study of the composition
and properties of materials and the way
in which they interact with the oral
environment in which they are placed.
Dental biomaterials may be classified
according to nature into, ceramics,
metals, polymers and composites or
according to use into restorative and
auxiliary materials
WHAT is the THIRD CLASSIFICATION?
I- Metals
Metals are used for making restorations of
the lost tooth structure, prosthetic devices,
orthodontic appliances, and many other
applications where strength and elasticity
are required.
A mixture of two or more metallic elements is
called alloy (Gold alloy &Cobalt chromium
alloy)
Metallic restoration
II- Ceramics
Ceramics include a wide variety of
substances such as glass, cement,
refractory (high temp), and many
other materials.
Types of dental ceramics:
 Dental porcelain.
 Dental cements.
 Gypsum products.
 Casting investment
Ceramic restoration
Ceramo-metal system
Bridge
III- Polymers
Polymers are synthetic resins.
Types of dental polymers:
 Polymeric impression materials.
 Denture base materials.
 Tooth colored restorative materials.
Polymeric denture base
Esthetic restoration
(dental composite)
1-Enamel.
2-Dentine.
3-Gingiva (Gum).
4-Gingival Sulcus.
5-Periodontal
Ligaments.
6-Pulp Chamber.
7-Root Canal.
8-Apical Foramen.
9-Bone.
10-Cementum.
1. Enamel:
Is the hardest structure in the human
body.
It forms the outer layer of the crown
It’s the only visible portion of the
crown.
2. Dentine:
Is the main substance of the
crown & the root.
Is yellowish-white in color.
Is sensitive.
Saliva
Contents:
1- Water.
2- Electrolytes.
3- Mucus.
4- Enzymes.
Functions:
1. Helps in creating the bolus of the food.
2. Amylase enzyme that converts starch into
dextrin.
3. Prevent tooth decay& tooth erosion due to
its buffering properties.
4. Saliva carries ions as calcium,fluoride….
That helps in remineralization.
5. Antibacterial.
The restorative material present in the
oral environment is subjected to:
1. Changes in temperature.(Thermal
properties)
2. Variation in pH.(Corrosion)
3. Occlusal stresses.
4. Solubility and disintegration.
5. Change in color(Optical properties)
Tempromandibular Joint
Functions:
1. The
first
function
is
rotation
around a horizontal axis.
2. The
second
function
is
translation where the condyle &
the disc move together anteriorly
beneath the articular eminence.
DENTAL BIOMATERIALS
I -Basic science of biomaterials
• Physical properties
Thermal properties
Optical properties
Surface chemistry
Corrosion
• Mechanical properties
• Basic structure of metals.
• Basic structure of polymers.
• Basic structure of ceramics.
II APPLIED BIOMATERIALS