PRESENTED BYREKHA KUMARI

ROLL NO 03

AMALGAM BONDING

CONTENTS /ROUTE MAP

IntroductionTypes of bondingTypes of bonding systemsDentin bonding systemsIndicationsAdvantages / disadvantagesTechniqueLiterature support

DENTAL AMALGAM

Most commonly used dental restorative materialFirst introduced in France in the early 1800s*Contains a mixture of mercury with at least one

other metal.Restorative method of choice for many years due

to  a.Low cost b.Ease of application c.Strength d.Durability e.Bacteriostatic effects*Ferracane, Jack L. (2001). Materials in Dentistry: Principles and Applications. Lippincott Williams & Wilkins. pp.

Factors that have led to recent decline in use are a lingering concern about 

  a.Detrimental health effects b.Aesthetics c.Environmental pollution.

INTRODUCTION TO BONDED AMALGAM

Amalgam-bonding resins were introduced in the 1980s,for and since then, the use of adhesives for amalgam has become a popular but not universal procedure.The introduction of newer resin Systems help overcoming the inevitable marginal leakage problem and thus providing improved marginal integrity.

Staninec M, Torii Y, Watanabe LG, Kawakami M, Tonn EM. Tensile adhesion evaluation in a new universal test. Am J Dent 1992;5:187–191. .

TYPES OF BONDING

MECHANICAL

ADSORPTION

DIFFUSION

COMBINED

BONDING OBSERVED IN AMALGAM

MECHANICAL BONDING:

The attachment mechanism between adhesive & Amalgam is not fully understood , but it may be

micromechanical entanglement of uncured adhesive with the setting amalgam mix during

condensation of the amalgam.

ENAMEL orDENTIN

DENTALAMALGAM

AMALGAMBONDING SYSTEM

Amalgam ReactionProduct MatrixResidualAmalgam Alloy

AMALGAM BONDINGMechanical Interlocking

Interfacial Interlocking of phases

Amalgambond Plus(Parkell)

TYPES OF BONDING SYSTEMS

ON THE BASIS OF SUBSTRATE

ENAMEL BSDENTINE

ENAMEL-DENTINE BS

Intertubular dentin

Peritubular dentin

Dentinal tubule

Residual smearlayer particles

Residual smearplug particles

Macrotag Microtag

Conditioning

Priming

Bonding

COMPOSITE

HYBRID LAYER: resin microtags that are withinintertubular dentin and surround collagen fibers.

Collagen fibers

B. “Smear layer removal” and “hybrid layers”

DENTIN BONDING SYSTEMSIntroduction

A. Classification of bonding systems:1. Type of substrate (enamel, dentin)2. Generation number3. Number of components

E + nP + B or nEP + B E + nPB nEPBSelf-Etching Primer

Self-Etching Adh

nP =HEMA, … , (Polymers),Alcohol, H2O, Acet

E =H3PO4, H2O

B =Bis-GMA, TEGDMAAcetone or Alcohol

E =H3PO4, H2O

nPB =HEMA, … , TEGDMA (Polymers),Alcohol, H2O, Acet

B =MMA, Bis-GMA, TEGDMA,(Polymers),Acetone or Alcohol

Acid Monomer,HEMA,H2O

nEP =Acid Monomer,HEMA, Polymer,(TEGDMA), H2O, Alcohol

nEP =

E+nP+B E+nPB nEP+BSelf-Etching

Primer

nEPBSelf-Etching

Adhesive

Total-Etch Systems Self-Etch Systems

Reliable Bonding No Postoperative Sensitivity

HybridLayer

HybridLayer

HybridLayer

HybridLayer

hydrophilic

hydrophobic

Designing Bonding Systems

BONDING AGENT

PRIMER

ETCHANT

E+nP+B

US Companies

2 =

1 =

E+nPB

Japanese Companies

= 2

= 1

or nEP+BSelf-Etching

Primer

???

nEPBSelf-Etching

Adhesive

hydrophilic tooth structure

hydrophobic “restorative material”

Total Etch Systems

BONDING SYSTEMS2-COMPONENT SYSTEMS (nEP + B)• Clearfil SE Bond & LinerBond 2v (Kuraray)• Optibond Solo SE Plus (Kerr)• UniFil Bond (GC)• NanoBond (Pentron)

1-COMPONENT SYSTEMS (nEPB)• AQBond (Sun Medical)• Adper Prompt or LP3 (3M-ESPE)• iBond (Hereaus-Kulzer)• Xeno III (Dentsply)

3-COMPONENT SYSTEMS (E + nP + B)

• Scotchbond Multipurpose Plus (3M)• Permaquick (Ultradent)• Bond-It (Jeneric / Pentron)• All-Bond 2 (BISCO)• ProBond (Dentsply)

2-COMPONENT SYSTEMS (E + nPB)• Bond-1 (Jeneric / Pentron)• Easy Bond (Parkell)• Prime&Bond NT (Dentsply)• Single-Bond (3M)• Optibond Solo and Solo Plus (Kerr)• OSB Bonding System (ESPE)

INDICATIONS

Badly broken down tooth(when amalgam is used as core material for Provision of crown )

MOD cavities

To repair fractured amalgam restoration

To repair fractured cusps

Why bonded Amalgam?

Tooth reinforcement 

Increase fracture resistance of tooth structure(1)

Conservation of tooth structure

 Decrease short term microleakage(2)

1. Eakle WS,staninec Malay AM.Effect of bonded amalgamon the fracture resistance of teeth.J Prostho Dent1992; 68:257-260

2. Setcos JC, Staninec M, Wilson NH. Bonding of amalgam restorations: Existing knowledge and future prospects. Oper Dent 2000;25:121–129

3. Hadavi F,Hey JH,Ambrose ER,Elbadrawy HE.effect of different adhesive systems on microleakage at the amalgam composite resin interface.Oper Dent 1993 ; 18 :2-7.

• Less post-operative sensitivity(3)

• Less secondary caries(3)

DISADVANTAGES

Costly comparative to conventional amalgamTechnique sensitiveTime consumingPoor performance in strengthening of old

amalgam restorations(1 )

Hadavi F,Hey JH,Ambrose ER,Elbadrawy HE. The influence of an adhesive system on shear bond strength of repaired high copper amalgams. Oper Dent 1991;16:175–180

LITERATURE SUPPORT

OBJECTIVE:

To compare and contrast the longevity of conventionally placed dental amalgam

restorations with those placed using bonding techniques.

CONCLUSIONS:

Within the limitations of the study, bonding amalgams, compared to placing them conventionally, afforded no significant benefit upon restoration longevity. This, coupled with the emerging trend of an accelerating decline in longevity of bonded amalgams from 1,000 days onwards and with the greater cost, challenges the justification for routine bonding of amalgams.

REFERENCE :Br.Dent.J 2009 jan 24;(206) :E3; discussion88-9. Epub2009 jan 16