by dr khawaja rashid hassan head science of dental materials department w.m.d.c abbottabad

Post on 23-Dec-2015

217 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

TRANSCRIPT

MISCELLANEOUS DENTAL MATERIALS

BYDR KHAWAJA RASHID HASSAN

HEAD SCIENCE OF DENTAL MATERIALS DEPARTMENT

W.M.D.CABBOTTABAD

MISCELLANEOUS DENTAL MATERIALS

Materials used in MAXILLOFACIAL SURGERY.

Materials used in ENDODONTICS. Materials used in PERIODONTICS.

Maxillofacial materials

INTRODUCTION Maxillofacial materials are used to correct

facial defects.CAUSES OF FACIAL DEFECTS

Cancer surgeries. Accidents. Congenital deformities.

NOSES, EARS, EYES, ORBITS & OTHER PARTS OF HEAD AND NECK REGION

ARE REPLACED BY THESE PROSTHESES

MAXILLOFACIAL PROSTHESES

PROSTHETIC EYE PROSTHETIC EAR

MAXILLOFACIAL PROSTHESESPROSTHETIC NOSE

Maxillofacial materials

Following materials are used for the fabrication of maxillofacial prostheses.

1) POLYMETHYLMETHACRYLATE.2) POLYURETHANE.3) ROOM TEMPERATURE-VALCUNIZED

SILICONES.4) OTHER ELASTOMERS.

Maxillofacial materials

1) POLYMETHYLMETHACRYLATE: P.M.M.A was once commonly used for

maxillofacial prostheses. Still used occasionally to make artificial

facial parts. Look quiet realistic once properly

pigmented.Hardness & stiffness of P.M.M.A is

the main disadvantage.

Maxillofacial materials

2) POLYURETHANE:

a) Used as maxillofacial materials.b) Formed by the reaction of

diisocyanate & polyol in the presence of an initiator.

c) Reaction must be carried out in a dry atmosphere or carbon dioxide will result.

d) Processing temperature of 100 ̊C is reasonable.

Maxillofacial materials

3) ROOM TEMPERATURE VALCUNISED SILICONES:

a) Because of good physical & mechanical properties & favorable processing characteristics RTV-Silicones have become popular maxillofacial materials.

b) Used more often than any other material for fabrication of maxillofacial prosthesis.

c) They are easy to color.

Maxillofacial materials

4) OTHER ELASTOMERS:a) Several elastomers have been

investigated for use as maxillofacial materials, including

b) Aliphatic polyurethanes.c) Chlorinated polyurethane.d) Organophosphazenes.e) Silicone poly(methyl meth acrylate)

block polymers.

ENDODONTIC MATERIALS

Endodontics is concerned with the physiology,

morphology & pathology of the human dental pulp &

periradicular tissuesTreatments include:a) Capping of exposed vital

pulp.b) Sealing of root canal space

after removal of infected pulp.

c) Reconstruction with endodontic post & core systems in case of badly broken down tooth.

ENDODONTIC MATERIALS

a) Vital pulp capping:Two types

Indirect pulp cappingDirect pulp capping

PULP CAPPING MATERIALS:1) Calcium hydroxide cement.2) Dentin bonding agents.

ENDODONTIC MATERIALS

b) ROOT FILLING MATERIALS:Most widely used root canal filling materials

are basically a combination of I. Obturating points

&II. Canal sealer cements.I) OBTURATING POINTSA) Gutta percha points.B) Metal points.

ENDODONTIC MATERIALS(OBTURATING POINTS)

A) GUTTA PERCHA POINTS:

Gutta percha is a rubber obtained from the trees in Malaysia.

Was introduced in U.K IN 1843.

Thermoplastic material. Softens at 60-65 ̊C &

melts at about 100 ̊C. Cannot be heat

sterilized but can be disinfected.

Gutta percha when cooled rapidly forms a crystalline β phase whereas when cooled slowly a denser crystalline α phase is formed.α phase gutta percha has better thermoplastic characteristics and hence preferred to be used in hot gutta percha systems

ENDODONTIC MATERIALS(OBTURATING POINTS)

OBTURA II OBTURA III

ENDODONTIC MATERIALS(OBTURATING POINTS)

COMPOSITION OF GUTTA PERCHA POINTS

CONSTITUANT AMOUNT (%) PURPOSE

GUTTA PERCHA

19-22 RUBBER

ZINC OXIDE 59-75 FILLER

HEAVY METAL SALTS

1-17 RADIO-OPACIFIER

WAX or RESINS

1-4 PLASTICIZER

ENDODONTIC MATERIALS(OBTURATING POINTS)

B) METAL POINTS: Metals including gold, tin, lead &

silver had been used as root canal filling materials.

Silver points were used mostly because of bactericidal effect.

Rigidity & ability to get corroded easily were the 2 main disadvantages of silver obturating points.

ENDODONTIC MATERIALS(ROOT CANAL SEALER MATERIALS)

IDEAL PROPERTIES OF ROOT CANAL SEALER CEMENTS

Should be biocompatible. Should be bacteriocidal or atleast bacteriostatic. Easy to use. Should be insoluble. Should be free of air bubbles when mixed. Floe to thin film thickness. Should adapt to the canal walls & obturating points. Should be radiopaque. Should be easily removed in case of failure.

ENDODONTIC MATERIALS(ROOT CANAL SEALER MATERIALS)

ROOT CANAL SEALER MATERIALS: ZINC OXIDE EUGENOL. GLASS IONOMER CEMENT. CALCIUM HYDROXIDE CEMENT. POLY DI METHYSILOXANE.

ENDODONTIC MATERIALS(POST & CORE SYSTEMS)

PREFABRICATED POSTS: Metal posts

1) Non threaded parallel sided posts.2) Threaded parallel sided posts.3) Non threaded tapered posts.4) Threaded tapered posts.

Fibre reinforced resin posts1) Carbon fibre reinforced posts.2) Glass fibre reinforced posts.

Ceramic posts1) Cosmopost.2) Biopost.3) Cetapost.

PERIODONTAL MATERIALS

1) Zinc oxide eugenol formulation.2) Zinc oxide fatty acid formulation.3) Formulation including polyacrylic acid,

poly ethyl methacrylate, zinc oxide, n-butylphthalate & alcohol.

This Ends Your Science of Dental Materials Course

GOOD LUCK FOR YOUR

PROFESSIONAL EXAMZ

top related