60548324 Dental Cements PPT PDF

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artigo científico prótese (cimentos odontológicos)
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DENTAL CEMENTS for Luting and Bonding Stephen C. Bayne Operative Dentistry UNC School of Dentistry Chapel Hill, NC 27599-7450

2004, Bayne and Thompson, UNC School of Dentistry.

RETENTION BY DENTAL CEMENTS Coarse and fine micromechanical retention

DENTIN

DENTAL JOINTS ADHESIVE SYSTEM or LUTING CEM ENT

Adherend

ENAM EL, DENTIN > Liner, Base, Cement > Post and Core > Dental Amalgam > Implant >

Adhe Adherreend nd

< Composite, Amalgam < Cast Inlay, Onlay, or Crown < All--ceramic Inlay, Onlay, or Crown < Veneers, Maryland Bridges < Orthodontic Brackets

Crown

GOALS: • Retention / resistance form • Sealing (No fluid fluid flow flow or ML) Microleakage

CEMENT FACTS: • • • • • • • •

???

Tooth Structure

Fluid Flow

No correlation of lab and clinical performance. RMGI for metal substructures and composite for ceramics. Failure occurs by fatigue – crack formation and propagation. Compositions and properties constantly changing. Cements are theoretically strong enough. Initial effectiveness requires “retention and sealing.” ling.” Init Cement more stable at enamel rather than dentin margins. Highest stress in cements occurs at margins.

C EMENT MICROST CE OSTRUCTURE Ceramic POWDER Particles (BASIC) Inorganic or organic LIQUID (ACIDIC)

s

Powder reinforces set ce

Zin c Phosphate C Zinc

OVERV W OF DENTAL CEMENTS OVERVIE EW Cement Type: Type:

(Abbr.) (Abbr.)

LIQUID LIQUID

POWDER

Zinc Oxide Eugenol:: ZOE Reinforced ZOE ZOE-EBA HV-EBA

(ZOE) (RZOE) (EBA) (HV-EBA)

Eugenol Eugenol Eugenol Eugenol Eug, Eug, EBA EBA HV, HV, Eug Eug

ZnO ZnO, Polymer, Rosin ZnO, Al2O3 , Rosin ZnO, Al2O3 , Rosin

Zinc Phosphate Silicate Zinc Silicophosphate Zinc

(ZP) (ZP) (SC) (ZSP) (ZSP)

H 3PO4 / H 2O H H3PO4 / H 2O H 3PO4 / H 2O

ZnO F-Al-Silicate glass ZnO, F- Al--Silicate

Polycarboxylate Glass Ionomer:: Conventional Resin-Modified Modified Compomer

(PC) (PC)

PAA PAA // H H2O

ZnO

(GI) (GI) (RMGI) (CM)

PAA / H2O F-Al-Silicate Glass ““ ++ H HEMA EMA,, … … F-Al-Silicate Glass (Monomers) (Monomers) F-Al-Silicate Glass

Composite Composite (with DBS) (CC, CP)

(Monomers) (Monomers)

(Silicate glass fillers) illers)

Dental Cement Timeline 1850

1900

1950

2000

ZOE ZP

SC PCC Compomer GI RMGI CC Contem porary Practice

Generations of Cements

Zinc Phosphate

Polycarboxylate

Resin-M odified Glass Ionomer

Glass Ionomer

Composite Cement

What do you use ???

Clinical Research Associates. Materials use survey. CRA Newsletter. 1990;14(12): 990;14(12):1; 1995;19(10):3 995;19(10):3-4; 2001… 2001…

Dental Cement Use

1990 1995 2001

--1% --EBA (ZOE) 22% 12% 10% Zinc Phosphate 33% 17% 5% Polycarboxylate GI , RMGI , Compomer 42% 65% 75 % Resin (Composite) 2% 6% 10% MultiLink

3M-ESPE RelyX UNICEM

IVOCLAR / VIVADENT

SETTING REACTIONS Final Set

75

% CONVERSION

% CONVERSION

100

50

25

0.1

Passes Large Indentor

50 Initial Set

Passes Small Indentor

25

TIME

1.0 Mixing Time

Mixing Interval

Working Time

Working Interval

Setting Time

Setting Interval

Initial Set

Final Set

DENTAL CEMENT PROPERTIES PHYSICAL PROPERTIES: -- Coefficient of Thermal Expansion -- Thermal Conductivity MECHANIC AL PROPERTIES: --- Compressiv ssive Stre eS trength --- Ten Tensile Stre sile Str ength --- Shear Strength --- Bond Strength CHEMICAL PROPERTIES: --- Solubility and Disintegration --- Absorption BIOLOGICAL PROPERTIES: -Chemical Irritation off P Pu Du Setting -- Che mical Irr itation o ulp D uring S etting

CROWN

E

DENTAL CEMENT PROPERTIES Physical Properties

Chemical Properties

Mechanical Properties____ ____

Setting

Solubility

CS

(w/o, 37°C, 37°C, 7d) 7d) (w/o,

(psi, 37°C, 7d)

0.02 to 0.10 .10 ---- to ------- to 0.40 ---- to to 00..01 01 0.05 to 0.10 .10 0.04 to 0.08 ??? ??? ???

2000 to 5500 10000 to 15000 ---------- to to ------------------------ to to --------------19000 to 21000 8000 to 18000 18000 to 24000 24000 to 30000 35000 to 45000

ll (( m/cm)

ZOE ZOE R R-ZOE ZOE ZOE- EBA HV HV-EBA ZP ZP PC PC GI GI RMGI RMGI Composite Composite

-31 to -85 ---- to ----12 to -24 ---- to ---+15 to -7 +50 to +420 ??? ??? ???

???

Silvey RG, Myers GE. Clinical study of dental cements. VII. A study of bridge retainers luted with three different dental cements. J Dent Res 1978;57:703 -707. In a clinical study of three luting cements, 547 bridges and 162 crowns were permanently cemented. Patients were recalled at 6month intervals and the restorations were examined for looseness. A pattern of retainer type, cement type and retainer success was demonstrable.

5-Year Cement Retention: Reinforced ZOE, ZOE-EBA Zinc Phosphate Polycarboxylate

Crowns 98% 100% 96%

Bridges 92% 98% 95%

CEMENT AGING SOLUBILITY and DISINTEGRATION SOLUBILITY and DISINTEGRATION ADA Test

ZINC PHOSPHATE CEMENT

Multifactorial Solubility and Disintegration Events

Water Zn(OH)2 Mg(OH)2 Zn(PO4)2 H2O, Lactic acid Na+, ClFCa+, K+

Cement ZnO (and MgO), Tertiary ZP Crystals

CROWN 100

CEMENT THICKNESS (100 m)

90 80 70 60 50 40 30

Powder CRACK Particle Erosion

20 10

RETENTION? SEALING?

0 TOOTH

LARGE PORE New Phase Precipitation

typical. d d ide ideaal.l.

RELATIVE STRENGTH (%)

100

80

60 y = 100e-0.0598x R2 = 0.9101

40

20

0 0

20

40

60

80

100

POROSITY (%) Ryskewitsch. J Am Ceram Soc 1953;36:65. (Empirical suggestion where n=4-7 and P=volume fraction porosity.)

=

oexp(-nP)

C E M E N T M AN IP U L A TION “20 different experienced dental assistants mixing the same cement” nt” Success / Failure Factors:

Frequency (n)

(2) Design Factors 5 (4) Intraoral Location Factors (5) Patient Factors

4 3 2 1 40

50

60

70

80

90

Compressive Strength (MPa)

ZOE-EBA

T Ce De nta Trra aditional C eramic D ent al Cement

ZnO

Eug + EBA ZnO

CH2-CH=CH2

(Zinc Eugenolate)

HO OCH3 (Eugenol)

CH2-CH=CH2

H3CO HO

Zn+2

HO

ZnO +

OCH3

OCH2CH3

OCH2-H3 (EBA)

COOH

CH2=CH-CH2

C-OH +2 O O- Zn HO-C H3CH2CO

(Zinc Ethoxy Bemzoate)

ZINC PHOSPHATE CEMENT Setting Reaction Setting Reaction

ZnO

H3PO4 in H 2O

ZnO + 2H3PO4 + H2O Zn(H2PO4)2- nH2O Caut Cautiion ons: s: Do Do not not u use se on on RDT RDT...