Punjabi 2016 handout Hewlett - pdsociety.com€¦ · 3 Tooth-Restorative Interface Enamel Bonding Resin-Enamel Bonding Image: Peumans, et al. J Dent 2000 Hybridized Zone

1

Adhesive Restorative Principles for Successful Esthetic Dentistry

Punjabi Dental SocietyAugust/September 2016

Edmond R. Hewlett, DDS

Disclaimer

No financial interest in any products discussed.

No contractual or non-contractual agreements with any manufacturers/corporations.

Today…

Adhesion overview

Vital pulp therapy

Composite resin – Glass ionomer synergy

Ultraconservative Caries Removal

2

(Perdigao, J.)

Tooth-Restorative Interface

3

Tooth-Restorative Interface

Enamel Bonding

Resin-Enamel Bonding

Image: Peumans, et al. J Dent 2000

Hybridized Zone

4

Enamel Surface Conditioners > 60 years of clinical experience with

phosphoric acid etching

Predictable and

Durable!

As good as it gets

Selective Etching…

…with self-etching adhesives PRE-ETCH enamel w/phosphoric acid for best seal

30-45 seconds

Dr Mario de Goes

Enamel as a Bonding Substrate

Aprismatic enamel at surface must prep for optimal bonding

Bevel

Disc

5

White Lines at Margins?

Gaps/voids, enamel microfractures Space fills with polishing debris

Enamel margins: BEVEL 25-40 µm diamond

Occlusal margins: REMOVE SHARP EDGE Remove unsupported enamel

Disk beyond the bevels

White Lines at Margins?

Etch with phosphoric acid 30-45 sec. on enamel

Rinse thoroughly

WAIT 5-10 min. before finishing margins Polymerization 90% complete

after 10 min.

Dentin Bonding

6

Dentin as a Bonding Substrate

Complex

Heterogeneous Collagen Fiber Mesh


Complex

Heterogeneous Hydroxyapatite

deposited on a collagen fiber mesh


Complex

Heterogeneous Hydroxyapatite (HA)

deposited on a collagen fiber mesh

50% mineral (by vol.),20% collagen, 30% water

Tubules/Fluid

Cell processes

7


Structure is variable!

Intrinsically hydrophilic

Response to resin bonding procedures is less predictable vs. enamel


Variable tubule density variable surface

morphology

variable water content


Variable tubule densityTubule surface

area: 1%

Tubule surface area: 22%

8


Variable degree of mineralization Intertubular dentin – less mineralized

Peritubular dentin – more mineralized


Variable degree of mineralization Intertubular dentin – less mineralized

Peritubular dentin – more mineralized

(In-vitro testing done HERE)


Variable degree of mineralization

9


Variable degree of mineralization Sclerotic dentin hypermineralized Acid resistant low permeability: POOR

BONDING

Prepare?

Longer etch time?

???


Variable degree of mineralization Caries-affected dentin


Variable degree of mineralization Caries-affected dentin

Caries detector dyes potential for excessive dentin removal

absence of dye elimination of bacteria

10

What isnormal dentin?

Nanoleakage

• Dentin bonds made w/ hydrophilic adhesives are permeable to water

•Water sorption from dentin during and after bonding

•Hydrolytic breakdown of resin and collagen

•Permeability potential is material specific

Nanoleakage

(Perdigao, J.)

11


No such thing as “NORMAL dentin” Substrate variability = Bonding variability Don’t be complacent!

- Summary:

What?

Dentin-Resin Bonding:as simple as 1-2-3?

1. Acidic Conditioner (Etchant) dentin permeability

2. Hydrophilic Primer Hybridization

Resin tags

3. Adhesive Resin Stabilization and copolymerization

12

Dentin-Resin Bonding:as simple as 1-2-3?

1. ETCH

2. PRIME

3. BOND

Dentin-Resin Bonding

Acidic Conditioner (Etchant) dentin permeability

Prepared Dentin Surface

Smear layer

13

1. Acidic Conditioner (Etchant)

a. Dissolves/removes smear layer

b. Demineralizes – dentin permeability

1. Acidic Conditioner (Etchant)

c. Exposes a collagen fiber scaffold

2. Hydrophilic Primer

Infiltration of exposed collagen

14

2. Hydrophilic Primer

Infiltration of exposed collagen

“Hybrid layer”

3. Adhesive Resin

Stabilization of hybrid layer

Chemically bonds to composite

Hydrophilic

Hydrophobic

Product Classification

No Mix

(3-Step Etch & Rinse)


(2-Step Self-Etch)

(1-Step Self-Etch, Mix)

(1-Step Self-Etch, No Mix)

Universal

(2-Step Etch & Rinse), OR

(1-Step Self-Etch, No Mix), OR

(1-Step Self-Etch, Mix)?SCA

15


No Mix



(2-Step Self-Etch)



Universal




3-Step Etch & Rinse Systems

1. Etch 2. Primer 3. Adhesive Resin

Most predictable In use for > 20 years

Most versatile Light cure and chemical cure

Direct and indirect restorations


1. Etch 2. Primer 3. Adhesive Resin

+

16


Radiopaque adhesive liner

Newer Bonding Products

Newer “Generations” (5th, 6th, 7th)

Newer = Simpler ≠ Better!

Simplicity trade-offs

Simplicity less versatility

Simplicity less forgiving

Simplicity more hydrophilic


No Mix



(2-Step Self-Etch)



Universal




17

Two-Step Etch & Rinse Systems

1. Etch 2. Primer/Adhesive Resin

Primer and resin in one container

Simplified inventory and procedure

Most convenient for direct restorations

Two-Step Etch & Rinse Systems…

…and Self- or Dual-Cure Composites:

pH is incompatible with self-cure composites.

Self-cure (amines): + charge

Adhesives are acidic: - charge

(self-cure)+ + (adhesive)- = inactivation

Buildup and adhesive don’t stick together!

Image from Tay, et al, J Appl Oral Sci 2004)

“Bonded” core buildup pulled out with impression!

18


…and Self-Cure Composites:

Use a self-cure activator

+


…and Self- or Dual-Cure Composites:

Etch, rinse, place & cure adhesive

Place & cure thin layer of flowable composite

Place core buildup material

Two-Step Self-Etching Systems

1. Etch/Primer 2. Adhesive Resin

Adequate etch of enamel?

Bond to dual- or self-cure?

Durability is improving

19


No Mix



(2-Step Self-Etch)



Universal




Two-Step Self-Etching Systems

1. Etch/Primer 2. Adhesive Resin


No Mix



(2-Step Self-Etch)



Universal




20

One-Step Self-Etching Systems

One-Step Self-Etching Systems

1. Etch/Primer/Adhesive Resin

Adequate etch of enamel?*

Durability of bond to dentin? (too hydrophilic?)*

Incompatible with dual- and

self-cure (too acidic)*

*more so than Two-Step SE

What Do The Experts Say?

21


No Mix



(2-Step Self-Etch)



Universal





No Mix



(2-Step Self-Etch)



Universal





No Mix



(2-Step Self-Etch)



Universal




22

“Universal” Adhesive Systems –The End of “Generations”?

Updated chemistry Resin monomers

Less water, more alcohol


Recent clinical study – SB Universal: 200 NCCLs

Etch & rinse, moist dentin

Etch & rinse, dry dentin

Selective etch

Self-etch


Recent clinical study – SB Universal:

RESULTS at 18 mos.:

Retention: No differences Lost: 3 self-etch, 1 etch-rinse moist, 1 selective etch

More margin discrepancies with self-etch

23


Dentin:Moist or Dry?

Indirect w/Self-or Dual-Cure

Silane Primer on Ceramic?

ScotchbondUniversal (3M ESPE)

Either is OKMix w/ DCAApply, Dry, & Cure

Not needed

All-Bond Universal (Bisco)

Moist, Do NotDessicate for TE AND SE

Apply, Dry, & Cure Yes

Prime & Bond Elect (Caulk)

TE: Moist, Do Not Dessicate

SE: Dry

Mix w/ SCAApply, Dry, & Cure

Yes

Phosphoric-acid etching of dentin could nowadays be considered too aggressive for dentin, given all the consequences related to exposure of the vulnerable collagen.

“Phosphoric-acid etching of dentin could nowadays be considered too aggressive for dentin, given all the consequences related to exposure of the vulnerable collagen.”

- Van Meerbeek, et al., 2011

24

“Phosphoric-acid etching of dentin could nowadays be considered too aggressive for dentin, given all the consequences related to exposure of the vulnerable collagen.”

- Van Meerbeek, et al., 2011

How?

Durability of the resin-dentin bond

•Dentin bonds made w/ hydrophilic contemporary adhesivesdeteriorate over time:

•Degradation of exposed demineralized collagen fibrils by host enzymes from dentin

•Hydrolysis of unpolymerized resin by host enzymes from saliva

•Hydrolysis of hydrophilic resin components via water sorption

25

(cut dentin surface)


After etching:


After etching:

26


After etching:

After etching:


EXPOSED demineralizedcollagen fibers

Over-etchedUnder-primed

Susceptible to enzymes

27

EXPOSED demineralizedcollagen fibers

IncompleteResin Infiltration

Susceptible to enzymes

Sequential Etching…

… for Etch & Rinse products Enamel: etch for 30-45 sec.

Dentin: etch for 10 sec.

Dr Mario de Goes

Preventing Dentin Bond Degradation

Degradation of demineralized collagen matrix over time by enzymes (MMPs) Pashley, Tay, et al.-JDentRes 2004

Chlorhexidine may inhibit MMPs after etching or

before SE use

2% for 30 sec.

Blot dry

28

Dentin “Wetness”

Moist Dentin prevents collagen fiber collapse maintains permeability

(interfibrillar spaces)


Overdrying collagen fiber collapse(“collagen smear layer”)

reduced permeability


Overwet voids on bonded interface

29

Avoiding Collagen Fiber Collapse

Leave dentin MOIST for etch/rinse adhesives

Etch-Rinse-BLOT dry Don’t DESSICATE!

REWET overdried dentin with water

Self-Etching = Self Wetting– leave dentin DRY!

Water-based primers:

(Self-etching primers)

Don’t OVERWET!

Don’t REWET!

30

Dentin Desensitizers

Tubule sealers/blockers Fluorides

Oxalate solutions

Dentin bonding derivatives HEMA

Fluoride

Antibacterial


Considerations Effect on bond strength of resin adhesives?

Necessary/helpful for resin-bonded restorations?

Moisture Control

Establish Excellent Isolation moisture control is critical!

etched enamel attracts all liquids

“wet” or “moist” ≠ biofilm!

31

Dealing with contamination

Between etching and priming: air dry and re-etch

Between resin placement and light curing: blow-out resin and contaminants w/air

reapply resin & cure

During incremental layering scrub w/adhesive resin, air-thin, resume

layering/curing

Vital Pulp Therapy

Cao, et al. J Calif Dent Assn 2016

Vital Pulp Therapy

aka:

Direct pulp capping

Pulpotomy


32

Vital Pulp Therapy

Primary goal:

Preserve healthy pulp tissue to encourage pulpal repair by hard tissue bridge formation


- Ricucci D, et al. J Dent 2014

Vital Pulp Therapy

Critical Factors:

Hemorrhage control Sodium hypochlorite 5.25% bleeding AND disinfects

Seal out bacteria Bonded/sealed definitive restoration


Vital Pulp Therapy

ZOE?

Resin bonding?

Glass ionomer?

Calcium hydroxide?

MTA?

CSCs?

Formation of a hard tissue bridge - What material?

33

Vital Pulp Therapy

ZOE? High leakage, but eugenol kills bacteria (-/+)

Eugenol is cytotoxic (-)

Eugenol release drops quickly with time (-)

Resin bonding? Cytotoxic (-)

Poor outcomes in human studies (-)

Seal? (+/-)

Vital Pulp Therapy

Calcium hydroxide? Excellent antibacterial (+)

Long track record (+)

Bioactive molecule release (+)

Vital Pulp Therapy

Calcium hydroxide? Inconsistent outcomes

Success rate as time “Tunnel defects” in dentin bridges Allowes bacteria ingress

“CH…can no longer be considered the material of choice for VPT.”

- Cao, et al. J Calif Dent Assn 2016

34

Vital Pulp Therapy with Calcium Silicate Cements (CSCs)

Mineral Trioxide Aggregate (MTA) First developed as a sx. root repair material in 1993

Vital Pulp Therapy with CSCs

MTA (Mineral Trioxide Aggregate) Excellent biocompatibility and sealing ability (+)

Prolonged alkaline pH

Radiopaque (+)

High solubility (-)

Poor handling properties (-)

Prolonged setting time (-)


MTA (Mineral Trioxide Aggregate)

Success rate > calcium hydroxide Mineral infiltration zone at dentin interface

Long-lasting seal

Better dentin bridge density

35



Biodentine™

Chemically similar to MTA

Sets in 10-12 min. (vs. 3-4 hrs.)

“Mineral infiltration zone” at interface

Interim restoration – lasts up to 6 months


TheraCal LC™ Light-cured, resin-modified calcium silicate liner

Calcium release stimulates hydroxyapatite and secondary dentin bridge formation

Alkaline pH promotes healing

36


TheraCal LC™ Light-cured, resin-modified calcium silicate liner

Per msds: Portland Cement Type III <60%

Polyethlene glycol dimethacrylate <50%

Barium zirconate <10%

Neo MTA (NuSmile)MTA Flow (Ultradent)

Direct Pulp Capping Recommendations*

Rubber dam isolation

Clean tooth w/ NaOCl or CHX

Caries detector dye and magnification

Hemostasis w/ NaOCl, up to 15 min.

CSC over exposure and all surrounding dentin Cover MTA w/ Glass Ionomer liner/base

Well-sealed restoration

*Cao, et al. J Calif Dent Assn 2016

37


Tubule sealers/blockers Fluorides

Oxalate solutions

Dentin bonding derivatives HEMA

Fluoride

Antibacterial


Considerations Effect on bond strength of resin adhesives?

Necessary/helpful for resin-bonded restorations?

Dentin Bonding:

Controlling the Variables

38


Product choices 3-step etch/rinse

2-step etch/rinse

Self-etching

solvent type?

monomer type?

filler?

mixing?

Technique choices etch time?

wet, moist, or dry?

disinfectant?

desensitizer?

application time?

apply once? twice?...

drying technique?

curing technique

flowable liner?


Product choices3-step etch/rinse

2-step etch/rinse

Self-etching

solvent type?

monomer type?

filler?

mixing?

Technique choicesetch time?

wet, moist, or dry?

application time?


drying technique?

curing technique

flowable liner?

Substrate variables deep or shallow?

caries affected?

sclerotic?

tubule density?

fluid/pulpal pressure?

pulpal proximity

etch depth?

un-hybridized collagen?

smear layer components?

contamination?

39



2-step etch/rinse

Self-etching

solvent type?

monomer type?

filler?

mixing?


wet, moist, or dry?

application time?


drying technique?

curing technique

flowable liner?

Substrate variablesdeep or shallow?

caries affected?

sclerotic?

tubule density?


pulpal proximity

etch depth?



contamination?

Dentin-Resin Bonding –a pathway to predictability?


2-step etch/rinse

Self-etching

solvent type?

monomer type?

filler?

mixing?


wet, moist, or dry?

application time?


drying technique?

curing technique

flowable liner?


caries affected?

sclerotic?

tubule density?


pulpal proximity

etch depth?



contamination?

post-operative sensitivity!

40

Contraction Gap

Posterior Composite Placement Techniques

• Managing the “C-factor”• Incremental layering

• Flowable liner

• Low-energy curing light modes• Ramping

• Stepping• Pulse/wait

(Figures from Deliperi & Bardwell, JADA 2002)

Dentin-Resin Bonding –a pathway to predictability?


2-step etch/rinse

Self-etching

solvent type?

monomer type?

filler?

mixing?


wet, moist, or dry?

application time?


drying technique?

curing technique

flowable liner?


caries affected?

sclerotic?

tubule density?


pulpal proximity

etch depth?



contamination?

Placement choicesC-factor?

incremental layering?

flowable liner?

ramping?

stepping?

pulse/wait?

41

Resin-Dentin Adhesion:

Neutralizing the Variables

Neutralizing the Problems?

Use a product/technique combination which works for ALL substrate situations

Expand product choices to include glass ionomers!

Glass-Ionomers are NOTComposite Resins

Composite resin:

Resin Filler

(Bis-GMA) (glass, silica)

Components are mixed together,

but do NOT react chemically. (Static)

42

Glass-Ionomers: What are they?

Glass (powder) + acidic polymer (liquid)

Setting via an acid-base chemical reaction

Liquid is an AQUEOUS solution

GI is Water-based and Hydrophillic!

Setting = conversion from viscous paste to hard solid

Dynamic, not static

GI Advantages: Low Stress

Polymerization shrinkage, BUT…

Doesn’t challenge its own bond!

composite glass-ionomer

GI Advantages: The Bond

GI is Self-Adhesive

• Interdiffusion zone

• Sr and F diffuse into enamel/dentin from GIC

• An acid resistantchemical fusion zone

Milicich G, 2005; Ngo, 1997 and 2006

(Slide courtesy of Dr. Jane M. Chalmers)

43

GI Advantages: Milder conditioning

37% phosphoric acid vs. 20% polyacrylic acid

128

CA

RD

OS

O et al. J D

ent 2010

magnification 7000x

Source: G

C R

&D

Departm

ent

GI Advantages: Milder conditioning

magnification 10,000x

37% phosphoric acid vs. 20% polyacrylic acid

GI Advantages: Bond variability

Predictable, consistent quality of adhesion

Glass Ionomer

Bovine dentin

44

GI Advantages: Fluoride release/uptake

At tooth-

restorative

interface

At restoration

surface

enamel

dentinF-

F-F-

F-F-F-

F-F-

F-

F-

F-

F-

F-

F-

F- F-F-

F- F- F-

GI Advantages: Dentin seal

Better resistance to microleakage at dentin margins vs. resin

GI Advantages: Dentin seal

Better resistance to microleakage at dentin margins vs. resin

Bond quality

Less techniquesensitive

Inhibitory activityon cariogenicbacteria

45

Posterior composites

Preventing post-op sensitivity:

Establish a gap-free resin/dentin interface

OR

Use the sandwich technique

Sandwich Technique

Utilizes functionally-compatible

dentin and enamel analogues

Sandwich Technique

Replace dentin with glass ionomer

Replace enamel with composite resin Chemical bond to dentin without etching

Fluoride release

Reduces technique sensitivity

Increased efficiency (faster!)

46

Sandwich Technique

Glass Ionomer Conditioner

Place GI base in bulk & cure

Etch/prime/bond

Place composite resin

Case by: Dr. Sameer PuriPosterior Class II RestorationMaterials: UniFil BOND, Etchant Gel, Fuji IX GP and GRADIA DIRECT

Pre-op Initial preparation

Carious dentin revealed

Caries indicator dye

Decay Removal

47

Caries removal Matrix placed

Fuji IX GP placed as base under composite

Fuji IX GP glass ionomer base

Dentin Replacement

Caries removal

Matrix placed

Glass ionomer placed as base under composite

Glass ionomer base

Dentin Replacement

Primer and bonding agent applied

Bonding agent light-cured

Composite placement Composite sculpted with instrument and brush

Enamel Replacement

48

Matrix removed after light-curing composite

Restoration finished with bur and disc

Restoration polished

Completed restoration

Final Restoration

(from Hewlett ER and Mount GJ, J Calif Dent Assn 2003)

(from Hewlett ER and Mount GJ, J Calif Dent Assn 2003)

49

50

open sandwich closed sandwich

Glass ionomer

51

Glass Ionomer – Which Type?

Resin –Reinforced Translucent

Command Cure

High-Viscosity Self-Cure Packable

Highest strength

152

EQUIA Forte Fil

EQUIA Forte Coat

SEM: Side view

EQUIA Forte Coat

EQUIA Forte Fil

EQUIA Forte Coat fills porosities to increase physical properties of the restoration and offers a much smoother surface.

Transitional Restorations

52

Transitional Restorations

From Guzman-Armstrong & Warren, J Dent Ed June 2007

ERH


ERH

53


ERH

Dentistry and Photography by Dr. Dan Ward

Before & After Class I restoration using EQUIA Forte

Ultraconservative Caries Removal

54

Cochrane screenshot

Cochrane Summary

Authors' conclusions:

“Partial caries removal is…preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure.”

- Ricketts D, Kidd E, Innes NP T, Clarkson JE

Ultraconservative and cariostatic sealed restorations: results at year 10.- Mertz-Fairhurst, et. al., JADA, 1998

• Three groups

Bonded resin directly over frank caries Sealed conservative amalgam restorations Conventional amalgam restorations

• Both sealed restorations superior to conventional amalgam

• Frank caries was arrested in sealed restorations

55

ERH

ERH

…removing all infected and affected dentin.

Several studies call this approach into question.

ERH

56

“…cariogenic bacteria… isolated by a restoration…

pose no risk…”

“…strong evidence for the advisability of leaving behind infected dentin…”

ERH

“There is substantial evidence that removing all vestiges of infected dentin from lesions approaching the pulp is not required for caries management.”

ERH

ERH

Mertz-Fairhurst, et al. J Am Dent Assoc. 1998;129(1):55-66

57

Mertz-Fairhurst, et al. J Am Dent Assoc. 1998;129(1):55-66

“There is substantial evidence that removing all vestiges of infected dentin from lesions approaching the pulp is not required for caries management.”

ERH

Partial v. Stepwise Caries Removal (Maltz, et al., 2012)

Inclusion Criteria Adults

Permanent molars

Caries lesion ≥ ½ of dentin on radiograph

+ Response to cold test Spontaneous pain Percusion sensitivity PARL

58


Partial Caries Removal (PCR)

Visit 1: Excavate, but leave soft

dentin over pulp

GI liner, composite resin

Stepwise Excavation (SW)

Visit 1: Excavate, but leave soft

dentin over pulp

Dycal, IRM

Visit 2 ( 90 days later): Re-open and remove

remaining demin’d dentin

Final restoration


Partial Removal – 152

91% Survival

Stepwise Removal – 147

69% Survival

299 Treatments

----------Outcome Success = Pulp Vitality----------(cold test, PARL)

--------------------3-Year Follow-up --------------------

Adv Dent Res. 2016 May;28(2):58-67.

59

Adv Dent Res. 2016 May;28(2):58-67.

“Nonselective removal to hard dentine … (formerly complete excavation or complete caries removal) is considered overtreatment and no longer advocated.”

Caries Removal – A Paradigm Shift

Remove all soft dentin

STOP when firm/dry to avoid pulp exposure

DON’T excavate to point of pink, “blushing”

SEAL in remaining bacteria with GLASS IONOMER

Thank [email protected]

Punjabi 2016 handout Hewlett - pdsociety.com€¦ · 3 Tooth-Restorative Interface Enamel Bonding Resin-Enamel Bonding Image: Peumans, et al. J Dent 2000 Hybridized Zone

Documents