Dentalni Biomaterijali PPT

8/4/2019 Dentalni Biomaterijali PPT

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By

Prof.Dr/Mona Hussein



The science of dental biomaterials involves

the study of the composition and properties

o ma er a s an e way n w c ey

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



Materials used in dentistry are confined

within the three known groups:

metals, ceramics and polymers.



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.

ypsum pro ucts.

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

.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

e roo .

Is yellowish-white in color.

Is sensitive.



3. Gingiva(Gum):

Is the soft tissue covering the bone

enc rc ng e oo near e

junction of the crown & the root.



4. Gingival sulcus:

Surrounds the tooth.

. .



5. Periodontal ligaments:

Attaches the tooth to the bone by means of

thin fibers.

Act as a shock absorber for the tooth.



6. Pulp chamber:

This cavity contains bloods vessels for

nutrition&nerves for the sensitivity of the

tooth.

Is extremely sensitive.



7. Root canals:

Are small canals through which blood

vessels& nerves pass through the roots

on their way to the pulp chamber.



8. Apical foramen:

Is the only normal opening of the root

canal.

The nerves & the blood vessels pass

from it to the root canal.



9. Bone:

The tooth is anchored in the bone.



10. Cementum:

A thin layer covering the root.

The ligaments attaches to this.



SalivaContents:

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

.

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.

3. Occlusal stresses.

4. Solubility and disintegration.



TMJ

Functions:

1. The first function is rotation around ahorizontal axis.

2. The second function is translation where

the condyle & the disc move together

anteriorly beneath the articular eminence.









DENTAL BIOMATERIALSI -Basic science of biomaterials

• Physical properties

Thermal properties

Optical propertiesSurface chemistry

Corrosion

• Mechanical properties



• Basic structure of metals.

• Basic structure of polymers.

• Basic structure of ceramics.

II APPLIED BIOMATERIALS



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Dentalni Biomaterijali PPT