Restorative Composite Resins

1
Restorative Composite Resins
Dr shabeel pn
2
Official Disclaimer

• The opinions expressed in this presentation are
  those of the author and do not necessarily
  reflect the official position of the US Air Force
  or the Department of Defense (DOD)
• Devices or materials appearing in this
  presentation are used as examples of currently
  available products/technologies and do not imply
  an endorsement by the author and/or the USAF/DOD

3
Overview

• Direct restoratives
• composition
• classification
• performance factors
• Flowable
• Packables

Click here for briefing on composite resins (PDF)
4
Composite

• Material with two or more distinct substances
• metals, ceramics or polymers
• Dental resin composite
• soft organic-resin matrix
• polymer
• hard, inorganic-filler particles
• ceramic
• Most frequently used
• esthetic-restorative material

Leinfelder 1993
5
History

• 1871 silicates
• alumina-silica glass phosphoric acid
• very soluble
• poor mechanical properties
• 1948 - acrylic resins
• polymethylmethacrylate
• high polymerization shrinkage

Rueggeberg J Prosthet Dent 2002
6
History(cont.)

• 1962 Bis-GMA
• stronger resin
• 1969 filled composite resin
• improved mechanical properties
• less shrinkage
• paste/paste system
• 1970s acid etching and microfills
• 1980s light curing and hybrids
• 1990s flowables and packables
• 2000s nanofills

Rueggeberg J Prosthet Dent 2002
7
Indications

• Anterior restorations
• Posterior restorations
• preventive resin
• conservative class 1 or 2

8
Contraindications

• Large posterior restorations
• Bruxism
• Poor isolation

9
Advantages

• Esthetics
• Conservation of tooth structure
• Adhesion to tooth structure
• Low thermal conductivity
• Alternative to amalgam

10
Disadvantages

• Technique sensitivity
• Polymerization shrinkage
• marginal leakage
• secondary caries
• postoperative sensitivity
• Decreased wear resistance

11
Composition

• Resin matrix
• monomer
• initiator
• inhibitors
• pigments
• Inorganic filler
• glass
• quartz
• colloidal silica
• Coupling Agent

Bis-GMA
Phillips Science of Dental Materials 2003
12
Monomers

• Binds filler particles together
• Provides workability
• Typical monomers
• Bisphenol A glycidyl methacrylate (Bis-GMA)
• Urethane dimethacrylate (UEDMA)
• Triethylene glycol dimethacrylate (TEGMA)

13
Monomers

• Bis-GMA
• extremely viscous
• large benzene rings
• lowered by adding TEGDMA
• freely movable
• increases polymer conversion
• increases crosslinking
• increases shrinkage

14
Monomers

• Shrinkage
• 2 7
• marginal gap formation

15
Filler Particles

• Crystalline quartz
• larger particles
• not polishable
• Silica glass
• barium
• strontium
• lithium
• pyrolytic
• sub-micron

Phillips Science of Dental Materials 2003
16
Filler Particles

• Increase fillers, increase mechanical properties
• strength
• abrasion resistance
• esthetics
• handling
• 50 to 86 by weight
• 35 to 71 by volume

Filler Volume
2
1.5
Fracture Toughness
1
0.5
0
0
28
37
48
53
62
Ferracane J Dent Res 1995
17
Coupling Agent

• Chemical bond
• filler particle - resin matrix
• transfers stresses
• Organosilane (bifunctional molecule)
• siloxane end bonds to hydroxyl groups on filler
• methacrylate end polymerizes with resin

Phillips Science of Dental Materials 2003
18
Inhibitors

• Prevents spontaneous polymer formation
• heat
• light
• Extends shelf life
• Butylated Hydroxytoluene

Phillips Science of Dental Materials 2003
19
Pigments and UV Absorbers

• Pigments
• metal oxides
• provide shading and opacity
• titanium and aluminum oxides
• UV absorbers
• prevent discoloration
• acts like a sunscreen
• Benzophenone

Phillips Science of Dental Materials 2003
20
Visible-Light Activation

• Camphorquinone
• most common photoinitiator
• absorbs blue light
• 400 - 500 nm range
• Initiator reacts with amine activator
• Forms free radicals
• Initiates addition polymerization

Bis-GMA
21
Polymerization

• Initiation
• production of reactive free radicals
• typically with light for restorative materials
• Propagation
• hundreds of monomer units
• polymer network
• 50 60 degree of conversion
• Termination

Craig Restorative Dental Materials 2002
22
(No Transcript)
23
Classification System

• Historical
• Chronological
• Based on particle size
• traditional
• microfilled
• small particle
• hybrid

Phillips Science of Dental Materials 2003
24
Traditional (Macrofilled)

• Developed in the 1970s
• Crystalline quartz
• produced by grinding or milling
• large - 8 to 12 microns
• Difficult to polish
• large particles prone to pluck
• Poor wear resistance
• Fracture resistant
• Examples Adaptic, Concise
• Suitable for Class 3, 4 and 5

Phillips Science of Dental Materials 2003
25
Microfills

• Better esthetics and polishability
• Tiny particles
• 0.04 micron colloidal silica
• increases viscosity
• To increase filler loading
• filler added to resin
• heat cured
• ground to large particles
• remixed with more resin and filler

Phillips Science of Dental Materials 2003
26
Microfills

• Lower filler content
• inferior properties
• increased fracture potential
• lacks coupling agent
• lacks radiopacity
• Linear clinical wear pattern
• Suitable for Class 3, 5
• exceptions with reinforced microfills
• Class 1 or 2

Click here for table of microfills
27
Small Particle

• 1 - 5 micron heavy-metalglasses
• Fracture resistant
• Polishable to semi-gloss
• Suitable for Class 1 to 5
• Example Prisma-Fil

Phillips Science of Dental Materials 2003
28
Hybrids

• Popular as all-purpose
• AKA universal hybrid, microhybrids, microfilled
  hybrids
• 0.6 to 1 micron average particle size
• distribution of particle sizes
• maximizes filler loading
• microfills added
• improve handling
• reduce stickiness

Phillips Science of Dental Materials 2003
29
Hybrids

• Strong
• Good esthetics
• polishable
• Suitable
• Class 1 to 5
• Multiple available

Click here for table of hybrids
30
Table of Properties
Phillips Science of Dental Materials 2003
31
Newer Classification System

• Based on particle size
• megafill
• 0.5 - 2 millimeters
• macrofill
• 10 - 100 microns
• midifill
• 1 - 10 microns
• minifill
• 0.1 - 1 microns
• microfill
• 0.01 - 0.1 microns
• nanofill
• 0.005-0.01 microns

• Most new systems
• minifillers
• Newest trend
• nanofillers
• trimodal loading
• prepolymerized

Bayne JADA 1994
32
Relative Particle Sizes (not to scale)
33
Nanofill vs. Nanohybrid

• Nanofills
• nanometer-sized particles throughout matrix
• Nanohybrids
• nanometer-sized particles combined with more
  conventional filler technology

Swift J Esthet Restor Dent 2005
34
Nanofilled Composite

• Filtek Supreme (3M ESPE)
• Filler particles
• filled 78 wgt
• nanomers
• 0.02 0.07 microns
• nanocluster
• act as single unit
• 0.6 1.4 microns

Click here for technical profile Click here for
DECS evaluation
35
Performance Factors

• Material factors
• biocompatibility
• polymerization shrinkage
• wear resistance
• polish mechanisms
• placement types
• mechanical physical properties

36
Biocompatibility

• Tolerated by pulp
• with good seal
• Rare allergic reactions
• HEMA
• Cytotoxicity
• short lived
• not a chronic source
• Degree of cure important
• decrease free monomer

Phillips Science of Dental Materials 2003
37
Systemic

• Estrogenic effects seen in cell cultures
• impurities in Bis-GMA-based resins
• Bis-phenol A in sealants
• Olea EHP 1996
• click here for abstract
• however, insignificant short-term risk
• literature review
• Soderholm JADA 1999
• click here for abstract

38
Polymerization Shrinkage

• Significant role in restoration failure
• gap formation
• secondary caries formation
• marginal leakage
• post-operative sensitivity
• Counteract
• lower shrinkage composites
• incremental placement

39
Composite Wear

• Less wear
• small particle size
• less abrasion
• heavier filled
• less attrition
• non-contact areas
• 3 - 5 times less
• less surface area
• anterior location
• premolars vs. molars

Hilton Oper Dentistry A Contemporary Approach
2001
40
Composite Wear

• Reduced wear with smaller particles
• less plucking leaving voids
• Higher filler loads for enhanced properties
• correlations between wear and fracture toughness
  and flexure strength
• Higher cure of resin matrix to resist scratching
  and gouging by abrasives

Hilton Oper Dentistry A Contemporary Approach
2001
41
Polish Mechanisms

• Acquired polish
• clinician induced
• Inherent polish
• ultimate surface
• Microfills
• high acquired, high inherent
• similar resin matrix and fillers wear more evenly
• Hybrids
• high acquired, acceptable inherent

Adept Report 1992
42
Polish Mechanisms
Small Particle Hybrid
Microfilled Composite
Acquired Polish
Time
Linear wear pattern
Inherent Polish
Adept Report 1992
43
Shaded vs. Anatomic Placement

• Shaded
• shade selected from middle third of tooth
• shade guide gives recipe for multiple shades
• Anatomic
• highly chromatic dentin matched to existing
  dentin
• colorless enamel replaces existing enamel

Click here for details
44
(No Transcript)
45
Placement TypesComposite Brands

• Shaded
• 4 Seasons (Ivoclar Vivadent)
• Esthet-X (Dentsply)
• Filtek Supreme (3M ESPE)
• Point 4 (Kerr)
• Venus (Heraeus Kulzer)
• Renamel (Cosmedent)
• Gradia Direct (GC)

• Anatomic
• 4 Seasons (Ivoclar Vivadent)
• Vitalescence (Ultradent)
• Miris (Coltene/Whaledent)

Jackson PPAD 2003
46
Composite Selection

• Anterior/stress (Class 4)
• hybrid
• mini- or midi-fill
• hybrid/microfill veneer combo
• Anterior/non-stress (Class 3 or 5)
• hybrid
• mini-fill
• microfill

47
Composite Selection

• Posterior
• hybrid
• mini- or midi-fill
• reinforced microfill

48
Selecting a Brand

• Contents of kit
• shades
• bonding agent
• unit-dose compules vs syringes
• Indications
• anterior, posterior, both?
• Cost of kit
• refills

Click here for synopsis of restorative composite
resins
49
Government Price(/gm of refill resin)
Prices current as of Jan 05
50
Selecting a Brand

• Results of lab and clinical studies
• Compositional characteristics
• filler content
• average filler particle size

Click here for synopsis of restorative composite
resins
51
Radiopacity(mm of aluminum)
ISO Requirement
Source USAF DECS Project 03-024
52
Surface Hardness(24 hrs)
Source USAF DECS Project 03-37
KHN
Horizontal lines connect nonsignificant
differences (plt0.05) N5
53
Flexural Strength(24 hrs)
Source USAF DECS Project 03-037
Horizontal lines connect nonsignificant
differences (plt0.05) N5
54
Volumetric Shrinkage
Source USAF DECS Project 03-037

Horizontal lines connect nonsignificant
differences (plt0.05) N5
55
Composite Variants

• Packable
• Flowable

56
Packable Composites

• Marketed for posterior use
• increase in viscosity
• better proximal contacts?
• handle like amalgam?
• Subtle alteration of filler
• shape
• size
• particle distribution
• Similar resin chemistry and filler volume

Click here for table of packable composites
57
Packable Composites

• Mechanical properties
• similar to hybrids

1.8
1.6
1.4
Fracture Toughness
ALERT
1.2
Solitare
1
SureFil
0.8
Heliomolar
0.6
Z100
0.4
0.2
0
Choi J Esthet Dent 2000 Click here for abstract
58
Proximal Contact Studies

• Packables similar to hybrids
• diameter and tightness
• Best contacts
• sectional matrix system

Peumans Dent Mater 2001 -click here for
abstract Klein Am J Dent 2002
59
Packable Composite Resin
Depth of Cure
Hardness Ratio
Choi J Esthet Dent 2000 Click here for
abstract
60
Packable Vs. Hybrid Composites

• Mechanical properties similar
• Wear properties similar
• Curing depths similar
• Similar proximal contacts
• Drier, denser feel

Click here for more details
Choi J Esthet Dent 2000
Peumans Dent Mater 2001
61
Flowable Composites

• Marketed
• class 1, 3, 5
• liner
• Particle size similar to hybrid composites
• Reduced filler content
• reduces viscosity

Percent Filler Loading
80
Aeliteflo
70
60
FloRestore
50
Weight Percent
Revolution
40
30
Ultraseal
20
10
Prodigy
0
Bayne JADA 1998 Click here for abstract
62
Liners Under Direct Composites

• Increased flow
• Increased shrinkage
• Improved marginal integrity?
• laboratory studies equivocal
• most studies show no benefit
• Braga JADA 2003
• click here for abstract
• Reduced post-operative sensitivity?
• no clinical evidence of reduction
• Perdigao Quint Int 2004
• click here for abstract

63
Polymerization Shrinkage

Tolidis JDR 1999
64
Radiopacity

• Reduced radiopacity?
• product specific
• may be more difficult to distinguish on radiograph

Murchison Quint Int 1999 Click here for abstract
65
Flowable Composite

• Mechanical properties
• inferior to hybrids

Fracture Toughness
Flexure Strength
Prodigy
Ultraseal
Revolution
FloRestore
Aeliteflo
0
0.5
1
1.5
2
2.5
0
50
100
150
200
MPa
MPa
Bayne JADA 1998 Click here for abstract
66
Flowable Composites

• Clinical applications
• preventive resin restorations
• small Class 5
• provisional repair
• composite repair
• liners??

67
Regular Material UsageCivilian Practitioners

• Flowable Composite 81
• Hybrid Composite 69
• Amalgam 67
• All-Purpose Composite 53
• Microfill Composite 52
• Resin-modified Glass ionomer 45
• Packable Composite 33
• Compomer 7
• Other 1

DPR 2005
Multiple responses
68
Review of Clinical Studies(Failure Rates in
Posterior Permanent Teeth)
Annual Failure
Hickel J Adhes Dent 2001
69
Review of Clinical Studies(Failure Rates in
Posterior Permanent Teeth)
Annual Failure
Standard Deviation
Longitudinal and Cross-Sectional Data
Manhart Oper Dent 2004 Click here for abstract
70
Purchasing ConsiderationsFederal Service

• Universal hybrid systems are suitable for both
  anterior and posterior restorations
• may not need to stock packable systems
• additional expense to maintain
• no improvement in mechanical properties
• no improvement in proximal-contact formation
• no increase in depth of cure

Click here for more details
71
Purchasing ConsiderationsFederal Service

• Most cases often only need one shade type
• Complex cases may need multiple shades applied in
  layers
• larger Class 4, direct veneers, diastema closures
• Wide diversity of kits available
• simple kits with only a few shades
• complete kits with multiple shades in various
  opacities bonding agents, dispenser guns, shade
  guides

Click here for synopsis of restorative composite
resins
72
Purchasing ConsiderationsFederal Service

• Simple universal hybrid kit in compact case for
  routine individual use in operatories or suites
• many systems available
• e.g., Prodigy (Kerr)
• More complete universal hybrid kitfor general
  use by entire facility or training program
• several systems available
• e.g., 4 Seasons (Ivoclar Vivadent)

Click here for synopsis of restorative composite
resins
73
Future Composites

• Low-shrinking monomers
• expanding spiroorthocarbonates
• epoxy-based resins
• liquid crystal
• Self-adhesive?

Click here for details
74
Acknowledgments

• Dr. Dave Charlton
• Dr. Jack Ferracane
• Dr. Tom Hilton

Questions/Comments

• Col Kraig Vandewalle
• DSN 792-7670
• ksvandewalle_at_nidbr.med.navy.mil