The document discusses the history and generations of dentin bonding agents. It describes the challenges of bonding to dentin due to its composition and structure. Early bonding agents bonded weakly to the smear layer rather than dentin. Current bonding agents condition and prime the dentin surface to allow resin infiltration and strong bonding. They are classified based on their treatment of the smear layer and number of clinical steps.

1. Presented by: Anuradha Roy
Collected by- Aziz Ikbal
Final year BDS
Dept. Of Conservative and Endodontics

2.  INTRODUCTION
 ROLE OF ADHESIVE DENTISTRY
 CONCEPT OF ADHESION
ENAMEL ADHESION
DENTINE ADHESION
CHALLENGES IN DENTINE ADHESION
 ENAMEL BONDING
STEPS FOR ENAMEL BONDING
MECHANISM INVOLVED
 DENTINE BONDING
CONDITIONING OF DENTINE
PRIMING OF DENTINE

3.  DENTINE BONDING AGENTS
CLASSIFICATION
GENERATIONS OF BONDING AGENTS
FIRST GENERATION
SECOND GENERATION
THIRD GENERATIONS
FOURTH GENERATION
FIFTH GENERATION
SIXTH GENERATION
SEVENTH GENERATION
 SUMMARY
 BIBLIOGRAPHY

4.  There is much interest and activity in dentistry today with dentin bonding agents.
 In the modern society, aesthetics has become a major concern for every individual .Thus most
of us desire for a perfect set of teeth.
 Therefore, teeth that have been deformed or ravaged by dental diseases need to be restored
to their natural form and colour.
 Moreover, the classic concepts of tooth preparation advocated in the early 1900s have
changed dramatically.
 Now more focus is laid upon conservative approach to the tooth preparation.
 Therefore the introduction of adhesive restorative materials has reduced the need
for an extensive tooth preparation.
 In order to successfully accomplish this, dentin bonding systems have been
introduced which bond the composite resin to the tooth structure.

5.  In 1955,Michael Buonocore described a clinical technique that used a
diluted phosphoric acid to etch the enamel surface to provide
retention of unfilled, self-cured acrylic resins.
 The resin would mechanically lock to the microscopically roughened
enamel surface, forming small "tags" as it flowed into the 10-µm to
40-µm deep enamel microporosities and then polymerized.
 The first clinical use of this technique was the placement of pit and
fissure sealants.
 The formation of resin micro tags within the enamel surface is the
basis of RESIN-ENAMEL ADHESION.
 The steps involved are:

6.  Acid etching transforms smooth enamel into an irregular
surface & increases its free surface energy
 Application of a fluid resin based material to the irregular
etched surface , facilitates penetration of the resin into the
surface aided by capillary action
 Monomers in the material are polymerised and the material
becomes interlocked with the enamel surface.

7.  Enamel etching leads to the following types of micro
morphological patterns:
 TYPE 1 ETCH PATTERN-dissolution of prism cores without
involvement of prism peripheries.
 TYPE 2 ETCH PATTERN-PERIPHERAL ENAMEL IS DISSOLVED ,
but the cores are left intact.
 TYPE 3 ETCH PATTERN-it is less distinct than the other two
patterns.

8.  Buonocore used 30-40% phosphoric acid.
 Currently,37% phosphoric acid in gel form is used.
 Silverstone found that the application of 30-40% phosphoric
acid resulted in a very retentive enamel surface.
 >40% - Calcium salts are less dissolved - ETCH pattern with
poorer definition.
 <27% - Formation of dicalcium phosphate dihydrate - cannot
be easily removed by rinsing.

9.  Currently, an etching time of 15 seconds is
used.
 An etching time of 60 seconds originally
was recommended for permanent enamel
using 30-40% phosphoric acid.
 However , studies show that a 15 second etch resulted in a
similar surface roughness as that provided by a 60 second etch.

11. Phosphoric acid is said to be a more aggressive acid,so
alternative etchants have been suggested:
 EDTA (24%; ph=7)
 Citric acid
 Tannic acid
 Maleic acid
 Polyacrylic acid
ALTERNATE ETCHANT SYSTEMS:
 Lasers
 Air abrasion-Al2O3 particles

12. LASERS
 Adhesion to dental hard tissues after Er:YAG laser etching is
inferior to that obtained after conventional acid etching.
 Enamel and dentin surfaces prepared by Er:YAG laser etching
show extensive subsurface fissuring that is unfavorable to
adhesion.
(J Prosthet Dent 2000.)
 Adhesion to laser-ablated or laser-etched dentin and enamel
was inferior to that of conventional rotary preparation and
acid etching.
( Dental Materials (2005) )

14.  Bonding to dentin is challenging & difficult.
 Adhesion to dentin occurs by mechanical method,chemical or both.
 But the main method is by penetration of adhesive monomers into
collagen fibrils which are exposed post acid etching.
 Structural differences exist between enamel & dentin.
 Therefore the following reasons account for challenges faced in
dentin adhesion:
 STRUCTURE OF DENTIN
 SMEAR LAYER
 STRESSES AT RESIN-DENTIN INTERFACE

15.  Enamel contains 90% of hydroxyapatite crystals whereas
dentin has only 50% and the rest is constituted by water(25%)
and type I collagen(25% by volume).
 Dentinal tubules exert pressure of 25-30mmHg, thus creating
decreased stability of bond between composite resin and
dentin.
 The number of dentinal tubules decreases from about 45000
near the pulp to 20000 near DEJ

17.  It is the residual organic or inorganic components formed
when a tooth is prepared using a bur or other instrument.
(Sturdevant’s Art & Science of operative dentistry,4th edition)
 It is 1-10 µm thick .

18. COMPOSITION OF SMEAR LAYER:
 According to SEM studies done by Shulien TM(1988),it
consists of:
 Small particles of mineralized collagen matrix
 Inorganic tooth preparation
 Saliva
 Blood
 Bacteria
 According to branstroem,the organic component
consisted of coagulated proteins from collagen
denatured by frictional heat of cutting.

19.  Therefore optimal bonding can occur by:
1.Removal of smear layer by using etch and rinse adhesives.
2.Incorporation of smear layer into bonding layer by self-
etch adhesives
Complete removal of smear
layer increases the dentin
permeability by 90%.

20.  It is defined as ”a thin layer of resin applied between conditioned
dentin and resin matrix of a composite.”
 The term dentine bonding agents is no longer relevant as current bond
agents bond to enamel and dentine.
 Due to acid –etching ,micro leakage or loss of retention is not a hazard
at the resin-enamel interface but its encountered at the resin-dentine
interface.
 Due to the differences in the composition of enamel and
dentine,developing agents that will adhere to dentine was challenging
due to the following reasons:
 The high water content interferes with bonding.
 Presence of a smear layer on the dentine surface.

21.  Therefore the bonding agent should be hydrophilic to
displace the water ,permitting it to penetrate the
porosities in dentine and react with the inorganic/organic
components.
 But, restorative resins are hydrophobic, therefore the
bonding agent should contain both hydrophilic and
hydrophobic components.
 The hydrophilic part bonds with either calcium or
collagen whereas the hydrophobic part bonds with the
restorative resin.

22.  It is the etching of dentin surface with acids or
calcium chelators.
 So, when acid is applied to it, dissolution of
hydroxyapatite crystals in intertubular dentin
and outer surface of peritubular dentin occurs
 Ultimately, the smear layer gets removed and
collagen fibrils are exposed.
 Materials used are: 1. 37% phoshporic acid
2. nitric acid
3. citric acid
4. EDTA
(ethylene diamine tetra-acetic acid)

23. Ideal duration is 15-20 seconds.
Increased duration: greater collapse
of collagen due to denaturation.
Decreased monomer infiltration.
Decreased duration: insufficient
depth of etching.

24.  It is the process of applying primers to the etched/conditioned
dentin surface to improve the diffusion of the adhesive resin
into moist and demineralized dentin
 Primer solution is a mixture of monomers with hydrophilic and
hydrophobic components dissolved in organic solvent
 Priming agents are HEMA(hydroxyethyl methacrylate) and 4-
META(4-methacryloxyethyl trimellitae anhydride)

25. Acid washing / rinsing
Removes smear layer
Dissolves HA
Drying shrinks remaining
Collagen polymer molecules
Rehydration / priming
Swells collagen
Mechanism of dentine bonding

26. Monomer penetration
Mechanism of dentine bonding
Monomer polymerisation
And collagen entanglement

27. 1. HISTORICAL STRATEGIES
 FIRST GENERATION(1965)
 SECOND GENERATION(1978)
 THIRD GENERATION(1984)
2. CURRENT STRATEGIES
 ETCH & RINSE ADESIVES
i. THREE STEP-ETCH &RINSE ADHESIVE(FOURTH GENERATION)
ii. TWO STEP –ETCH & RINSE ADHESIVE(FIFTH GENERATION)
 SELF ETCH ADHESIVES
 TWO COMPONENT –SELF ETCH ADHESIVE(SIXTH GENERATION)
o TWO STEP-TWO COMPONENT –SELF ETCH ADHESIVE
o ONE STEP –TWO COMPONENT - SELF ETCH ADHESIVE
 SINGLE COMPONENT-ONE STEP-SELF ETCH ADHESIVE(SEVENTH
GENERATION)

28. Current strategies
ETCH & RINSE ADESIVES SELF- ETCH ADHESIVES
THREE STEP-ETCH & RINSE ADHESIVE TWO STEP –ETCH & RINSE ADHESIVE
(FOURTH GENERATION) (FIFTH GENERATION)
TWO COMPONENT –SELF ETCH ADHESIVE SINGLE COMPONENT - ADHESIVE
( SIXTH GENERATION ) ( SEVENTH GENERATION)
TWO STEP-TWO COMPONENT –SELF ETCH ADHESIVE
ONE STEP –TWO COMPONENT - SELF ETCH ADHESIVE

29. BASED ON MODERN ADHESION STRATEGY:
Van Meerbek et al(2001) suggested a classification based on adhesion
strategy.
TYPE OF ADHESIVE STEPS INVOLVED
ETCH AND RINSE ADHESIVES
THREE STEP ADHESIVE:FOURTH GENERATION
TWO STEP ADHESIVE:FIFTH GENERATION
SELF ETCH ADHESIVES
TWO STEP ADHESIVE:SIXTH GENERATION
ONE STEP ADHESIVE:SEVENTH GENERATION

30.  BASED ON THE TREATMENT OF SMEAR LAYER:
 Smear layer modifying
 Smear layer removal
 Smear layer dissolving

31. DECADE BONDING AGENT FEATURES
1960s
1970s
FIRST GENERATION
SECOND GENERATION
• DENTIN ETCHING WAS CONTRAINDICATED
• ADHESION WAS TO SMEAR LAYER
• WEAK BOND STRENGTH
1980s THIRD GENERATION • ETCHING ENAMEL & DENTIN
• PRIMING-A SECOND STEP WAS DONE
• BETTER BOND STRENGTH
EARLY 1990s FOURTH GENERATION • TOTAL ETCH CONCEPT WAS INTRODUCED
• WET BONDING & HYBRID LAYER CONCEPTS INTRODUCED
• MULTIPLE TECHNIQUE SENSITIVE CLINICAL STEPS
MID 1990s FIFTH GENERATION • PRIMER & ADHESIVE COMBINED IN ONE BOTTLE
• HIGHER BOND STRENGTHS
LATE 1990s SIXTH GENERATION • INTRODUCTION OF SELF-ETCHING PRIMERS
• POST OPERATIVE SENSITIVITY WAS REDUCED
• LOWER BOND STRENGTHS
EARLY 2000s SEVENTH GENERATION • ALL IN ONE/ONE STEP BOND CONCEPT INTRODUCED
• BOND STRENGTH LOWER THAN 4TH & 5TH GENERATIONS

32.  Most products use a three-component system consisting
of a conditioner, primer, and adhesive.
1. CONDITIONER (CLEANSER, ETCHANT) –
 weak organic acid (e.g., maleic acid),
 a low concentration of a stronger inorganic acid (e.g.,
phosphoric or nitric acid)
 a chelating agent (e.g., EDTA).

33.  MAIN ACTIONS:
 Alters or removes the smear layer.
 demineralizes peritubular and intertubular dentin
 exposes collagen fibrils --demineralizes up to a depth of
7.5 microns.
 peritubular dentin is etched more deeply than the
intertubular dentin increases dentin permeability.

34.  PRIMER
 bifunctional monomer in a volatile solvent such as acetone or
alcohol
 examples of HEMA (hydroxyethyl methacrylate),
NMSA (N-methacryloyl-5- aminosalicylic acid),
NPG (N-phenylglycine),
PMDM (pyromellitic diethylmethacrylate), and
4-META (4- methacryloxyethyl trimellitate
anhydride).

35.  MAIN ACTIONS:
 Links the hydrophilic dentin to the hydrophobic adhesive
resin
 Promotes infiltration of demineralized peritubular and
intertubular dentin
 increases wettability of the conditioned dentin surface

36.  ADHESIVE (BONDING RESIN):
 It is an unfilled or partially-filled resin; may contain some
component of the primer (e.g., HEMA) in an attempt to
promote increased bond strength.
 MAIN ACTIONS:
 Combines with the primer s monomers to form a resin-
reinforced hybrid layer ( resin-dentin interdiffusion zone ) 1
to 5 microns thick.
 Forms resin tags to seal the dentin tubules

37.  It consisted of surface active co-monomer NPG-GMA(N-
phenylglycine glycidyl methacrylate)
 MECHANISM OF ACTION:
 This co-monomer could chelate with calcium on the tooth
surface to generate chemical bonds of resin to calcium.
 Example:
 Cervident(S S White burs,Lakewood)

38.  Clinical result:
 It had poor bond strength of 2-3MPa.
 Therefore when used to restore noncarious cervical lesions
without mechanical retention.

39. SECOND GENERATION DENTIN BONDING
AGENT:
 Introduced in 1978.
 They were based on phosphorous esters of methacrylate derivatives.
MECHANISM OF ACTION:
 Adhesion was by means of ionic interaction between the negatively charged
phosphate groups & positively charged calcium in the smear layer.
 Advantage:
 Bond strength was 3 times higher than the earlier ones.
 Disadvantage:
 Bond strength was still lower around 5-6 Mpa.
 Clinical failure due to the bonding instability in the wet oral environment &
their primary bonding to the smear layer and not the dentin.

40.  ADVANTAGE:
 Bond strength was 3 times higher than the earlier ones.
 DISADVANTAGE:
 Bond strength was still lower around 5-6 Mpa.
 Clinical failure due to the bonding instability in the wet
oral environment & their primary bonding to the smear
layer and not the dentin.

41.  EXAMPLES:
 Clearfil Bond System(Kuraray,Japan)
 Scotchbond(3M ESPE)
 Bondlite(Kerr Corporation.CA)
 Prisma Universal Bond(Dentsply)

42.  It was a phosphate based material containing HEMA and a 10-
carbon molecule 10-MDP(10-methacryloyloxy decyl
dihydrogen phosphate)
 These were introduced with Clearfil New Bond in 1984.
MECHANISM OF ACTION:
 The concept of phosphoric acid etching of dentin before the
application of a phosphate ester type of bonding agent was
put forward by FUSAYAMA et al in 1979

43.  Most of the other III generation bonding agents were designed
not to remove the smear layer but only to modify it and
therefore allow the penetration of acidic monomers like
pheny-P or PENTA(dipentaerythritol penta-acrylate
monophosphate)
 EXAMPLES:
 Clearfil New Bond(Kuraray)
 Scotchbond 2(3M ESPE)

44. Adhesive
system
Etchant Primer Adhesive Bond strength
Scotch Bond 2 2.5% maleic
acid + 55%
HEMA
HEMA Bis GMA 8.8 Mpa
Tenure
Oxalate bonding
system
aluminium
oxalate in 2.5%
nitric acid
NPG-GMA. BisGMA,
TEGDMA
15 Mpa
This generation attempted to deal with both the smear layer and dentinal fluid,
with following 2 approaches:
i. Smear layer modification to improve its properties.
ii. Remove s.layer without disturbing the smear plugs that occlude dentinal tubules.

45. 1. ETCH AND RINSE ADHESIVE:
The smear layer is considered to be an obstacle that must
be removed to permit resin bonding to dentin.
The next generation of dentin adhesives was introduced for use
on acid –etched dentin.
The clinical technique involves simultaneous application of an
acid to enamel & dentin.This was called as total-etch
technique.

46. MECHANISM OF ACTION:
application of acid to dentin results in complete or partial removal of
smear layer and demineralization of dentin
Intertubular & peritubular dentin are demineralised,thus exposing collagen
fibres & increasing microporosity of intertubular dentin
7.5µm of dentin is demineralised
Primer increases the free surface energy of dentin
Formation of resin tags and hybrid layer.

47. IT CONSISTS OF
ETCHANT PRIMER ADHESIVE

48.  Here three components came into being:
 Phosphoric acid etchant(in gel form)
 Primer –it consisted of hydrophilic monomers in ethanol ,
acetone or water.
 Primer is a bifunctional molecule having a hydrophilic
and a hydrophobic part.the former attaches to tooth
whereas the latter attaches to composite resin.
 Examples: HEMA
NTG-GMA
PENTA

49.  Bonding agent:
 It consists of unfilled or filled resin which may be
BisGMA(Bisphenol glycidyl methacrylate),UDMA(urethane
dimethacrylate) with TEGDMA & HEMA(2-hydroxyethyl
methacrylate).
 Thus after the application of primer and bonding agent to
etched surface aids in their penetration into intertubular
dentin to form a resin-dentin inter diffusion zone called
HYBRID LAYER which was introduced by Nakabayashi in 1982.

50.  ADVANTAGES:
 Higher bond strength of 17-24MPa.
 They show reliable and consistent results.
 DISADVANTAGES:
 Technique sensitive
 Time consuming procedure
 Over wetting or over drying of dentin may occur

51. • BRAND NAMES-
• All Bond 2 & All Bond 3
• Optibond FL(Kerr Corporation)
• Adper Scotchbond Multi-purpose(3M
ESPE)
• BOND STRENGTH-
• 17-30 Mpa.

52.  CLINICAL STEPS INVOLVED:
 STEP1:application of etchant gel(37% phosphoric acid) for
15 seconds .
 STEP2:rinse the etchant thoroughly and blot dry the
substrate
(moist bonding technique)
 STEP3:application of primer (bottle 1) on the substrate.
 STEP4:application of adhesive(bottle 2)on the tooth
substrate.
 STEP5: light cure .

53. 1st step:
-Total etching(removal of smear layer)
Leaving free minerals on surface
-Rinse surface
-Without drying of surface (residual water
left)
2nd step :
adding primer
3rd step:
Adding adhesive resin &
then composite
Composite
Smear layer
Residual
water
Primer
Adhesive resin

54.  DEFINITION
 “The structure formed in the dental hard tissue by
demineralization of the surface and the sub-surface followed
by infiltration of monomers & subsequent polymerization.”
( Nakabayashi,1982)
 It is a hybrid combination of the above two. It is a process
which creates a molecular level interfacebetween dentin and
composite resin.

55. ZONES
TOP LAYER MIDDLE LAYER BASE
TOP LAYER :loosely arranged collagen fibrils directed towards
adhesive resin.
MIDDLE LAYER: collagen fibrils separated by electron lucent spaces(10-
20nm) represent areas in which HA crystals have been replaced by resin
due to hybridization.
BASE : partially demineralized dentin.

56.  This was developed to simplify the procedures involved in
bonding.
 Therefore , the primer and the bonding agent is present in a
single bottle.
 COMPONENTS:
 ETCHANT GEL + PRIMER & ADHESIVE

57. It consists of
BOTTLE I BOTTLE II
(Etchant+Primer) (Adhesive)

58.  STEPS INVOLED ARE:
 STEP1:application of etchant gel.
 STEP2:rinse the etchant thoroughly and blot dry the
substrate
(moist bonding technique)
 STEP3:application of primer and adhesive (single
bottle)
 STEP4:light cure .
 BRAND NAMES:
 Prime & Bond NT(Dentsply)
 Adper single bond2
 ExciTE(Ivoclar,Vivadent)
 One coat Bond
 XP Bond

59.  They are defined as “bonding systems which dissolve the
smear layer and create porosities in the underlying
dental substrates without needing an extra conditioning
agent(eg:phosphoric acid) to be applied in a single step.
(Quintessence International,vol(8), nov-dec2013)
 No separate etching step is needed.
 ADVANTAGES:
 Decrease in the number of steps
 Less technique sensitive.

60.  The self-etching approach has been proposed in an effort to
simplify the dentin/enamel bonding systems.
 These materials combine tooth surface etching and priming
steps into one single procedure.
 The elimination of separate etching and rinsing steps
simplified the bonding technique and has been responsible
for the increased popularity of these systems in daily
practice.

61.  Based on the acidity of self-etch primers & adhesives, they
are classified as:
 Weak- pH-2
 Medium pH-1.5
 Strong pH≤1
 Most commonly pH ranges from1.3-2.7

62. SELF-ETCH ADHESIVES
2 COMPONENT SELF-ETCH ADHESIVES 1 COMPONENT SELF-ETCH ADHESIVES
(VI GENERATION) (VII GENERATION)
2 STEP & 2 COMPONENT I STEP BUT 2 COMPONENT

63. 1. 2 STEP : 2 COMPONENT SELF-ETCHING ADHESIVES:
(NONRINSING CONDITIONERS OR SELF PRIMING
ETCHANTS)
MECHANISM OF ACTION:
 These acidic primers contain phosphonated resin
molecule that performs two function:
 Etching and priming of enamel
 Incorporating smear plugs into resin tags.

64.  Steps involved are:
 Application of bottle I(etchant
+primer)
 After 10 s, application of bottle2 on
tooth surface
 Light cure
 BRAND NAMES:
 Clearfil SE Bond(Kuraray,Japan)
 AdheSE(Ivoclar-Vivadent)
 Optibond Solo Plus Self-etch(Kerr Corp)

65. 2. ONE STEP:TWO COMPONENT-SELF-ETCH ADHESIVE:
 consists of- BottleI +Bottle II
 Bottle I:conditioner +primer
 Bottle II: adhesive resin
 Both have to be mixed prior to application on tooth surface.
 BRAND NAMES:
 Xeno III(Dentsply)
 One up bond(Tokuyama)
 Prompt L bond(3M ESPE)

66.  Self etching primers are acidic in nature, leading to its
penetration along the aqueous channels found in the
smear layer and widening them.
 These offer a simpler clinical step when compared to
the tota;l etch adhesive systems.
 self etching primers contain acidic esters like
HEMA,TEGDMA,MDP.
 These primers are similar to those found in third
generation dentin bonding systems, the only difference
being that in the latter ones only milder acids were used
leading to inability to etch beyond the smear layer.

67.  In the sixth generation dentin bonding systems, acidic
monomers like 4-MET and 10-MDP are used ,thus
dissolving the smear layer.
 When the concentration of acidic monomers increasd
from 5-10% wt %(III generation dentin bonding agent) to
30-40% (VI generation dentin bonding agent) and
dissolved in 30-40% HEMA, pH-1-2 was developed which
aided in etching through smear layer.

68.  ADVANTAGES
 No etching needed, therefore possibility of over-etching or over-
drying is removed
 Less technique sensitive.
 Self-etch adhesives are less likely to result in discrepancy between
depth of demineralization and depth of resin infiltration as both the
processes are done simultaneously.
 Less time consuming
 DISADVANTAGES
 Decreased shelf life
 Incompatible with chemical cure composites.
 Self-etch adhesives that are currently available do not etch as
efficiently as phosphoric acid, especially if the enamel has not been
instrumented.

69.  TYPE 2 ( TWO BOTTLE 1 STEP SYSTEM):
 Liquid A contains primer.
 Liquid b contains a phosphoric acid modified resin.
 Both are mixed before application.
 Eg:Xeno 3(Dentsply),Adper-prompt L-pop(3M).

70.  Here the etchant, primer and the adhesive resin are
combined into one bottle .
 In vitro studies have shown that tooth-restoration interface
created when using self etching adhesives do not eliminate
the micro leakage and bacterial penetration, which can lead
to secondary caries.
 (Kakar S,Goswami M,nagar R.Dentin bonding agents-2 Recent
trials. World J Dent2012;3(1);115-118.

71.  ADVANTAGES OF VII GENERATION DENTIN BONDING AGENTS:
 Lesser application time
 Decrease in errors with each step.

72.  Examples are:
 iBond(Heraeus kulzer)
 G bond(GC)
 XenoIV(Dentsply)
 Clearfil S3(Curare)
 XenoV+
XenoV+

75.  In 2012, the term “universal adhesive” has been given
several definitions which are:
a)Can be used in total-etch, self-etch, and selective etch
techniques;
b)Can be used with light-cure, self-cure, and dual-cure
materials (without the separate activators);
c)Can be used for both direct and indirect substrates;
d)Can bond to all dental substrates, such as dentin, enamel,
metal, ceramic, porcelain, and zirconia.

76. In November 2011, a new “ScotchBond Universal”
was discovered.
Which needs a separate self-cure activator or a
special amine-free dual-cure cement when in use
with dual-cure or self-cure materials, hence not a
truly “universal” adhesive.

77.  In March 2012, a “All-Bond Universal” was discovered,
which can be used in:
i.total-etch, self-etch and selective etch
techniques,
ii.can be used with any dual-cure, self-cure and
light-cure materials without the need of a separate activator,
iii.can also be used for both direct and indirect
substrates, and can bond with any dental substrates.
 All-Bond Universal is the first truly “universal adhesive”.

78. In today’s era, numerous improvements in materials and
procedures have been made to meet the growing aesthetic
demands of the patients.
 In all the aesthetic restorations a bonding step is involved
to ensure durability and reliability.

79.  Thus the ideal bonding system should be biocompatible, bond
perfectly to enamel and dentin, have sufficient strength to resist
to failure as a result of masticatory forces, have mechanical
properties close to those of tooth, and be resistant to degradation
in oral environment and easy to use.

80.  STURDEVANT'S ART & SCIENCE OF DENTISTRY-4TH, 5TH
& 6TH EDITION
 PHILLIPS-SCIENCE OF DENTAL MATERIALS...11TH
EDITION
 TOOTH COLORED RESTORATIVES-PRINCIPLES AND
TECHNIQUES..9TH EDITION
 PICKARD'S MANUAL OF OPERATIVE DENTISTRY...8TH
EDITION