Luting Agents and Cementation Procedures PDF

Luting Agents and Cementation Procedures By Dr. Mohammed Hosny Professor of Fixed Prosthodontics Collage of Dentistry Taibah University 5/6/2023 M.Hosny 2 Learning Outcomes 5/6/2023 M.Hosny 3 Definitions Cement: Is a generic term for a joining medium provided adhesion and/or micromechan...

Luting Agents and Cementation Procedures By Dr. Mohammed Hosny Professor of Fixed Prosthodontics Collage of Dentistry Taibah University 5/6/2023 M.Hosny 2 Learning Outcomes 5/6/2023 M.Hosny 3 Definitions Cement: Is a generic term for a joining medium provided adhesion and/or micromechanical locking between the two surfaces to be connected Luting: A mechanism in which micromechanical locking occurs between the objects to be joining. Bond: Chemical or physical interaction occurs to both surfaces that to be attracted. Int.J.Curr.Microbiol.App.Sci (2015) 4(2):659 5/6/2023 M.Hosny 4 Ideal luting cement Requirements Biological Mechanical Esthetic Workability 1.Biocompatible. 1.High strength. 1.Translucency. 1.Acceptable working 2.Anticariogenic. 2.Low solubility. 2.Color stability. time. 3.No microleakage. 3.Adhesiveness. 3. Radiopacity. 2.Low film thickness. 4.Easy removal of 3.Low viscosity. excess cement. 5/6/2023 4. Ease of use M.Hosny 5 Classification of luting cements Provisional (Interim) 1. ZnO Eugenol cements. Definitive Non-Adhesive 2. Non Eugenol ZnO. Adhesive 1. Zinc phosphate. 1.Zinc Polycarboxylate. 3. Conv. Composite resin. 2.Glass Ionomer. 3.Resin modified G.I. 4.Adhesive resin cement. 5/6/2023 M.Hosny 6 Main purpose  The main purpose of luting cement is Hermitic seal by filling the microscopic spaces between restorative material and tooth preparation, as well as to enhance the resistance to restoration dislodgement during function . 5/6/2023 M.Hosny 7  Interim cement can be mixed with a little petrolatum.  Luting agent is applied only to the margins of the restoration to seal them and yet allow subsequent removal without difficulty Eugenol Non-Eugenol TempBond TempBond NE  Decrease post operative pain.  Decrease post cementation symptoms of hypersensitivity.  Bridge can be further removed for adjustment & modification.  To see if the patient accepts the esthetic.  To see the oral hygiene of the patient (follow oral hygiene instructions). 5/6/2023 M.Hosny 9 Provisional cement Zinc oxide-eugenol cements Compositions Powder  Zinc oxide  Rosin : reduce the brittleness of the set cement  Zinc stearate : plasticizer  Zinc acetate : improve strength Liquid  Eugenol and olive oil 5/6/2023 M.Hosny 10 Zinc oxide-eugenol cements Properties Lower strength than Zinc phosphate cement. Sedative effect. Bacteriostatic -- kills bacteria of carious cavities. Opaque – not used to lute translucent ceramic restorations. Water soluble -- dissolves in oral saliva. Easily mixed. 5/6/2023 M.Hosny 11 Zinc oxide-eugenol cements Manipulation Paste/paste  Mix two equal pastes together until it obtains the homogeneous color. Powder/liquid  Usually 4:1 for maximum strength  Mix the large increment, firstly  Not require cool glass slap 5/6/2023 M.Hosny 12 Provisional cement Non-Eugenol zinc oxide  The Liquid:  Ethoxybenzoic acid, known as ZOEBA  The powder:  Zinc oxide (90%)  For a patient who is known or suspected of being allergic to eugenol-containing products.  Can be used with acrylic resins and composite resin provisional restorations.  Recommended if you plan to use resin-based final cement. 5/6/2023 M.Hosny 13 Non-Eugenol zinc oxide  Manipulation:  Extrude equal lengths of Temp-Bond base (White color) and the accelerator (Brown color) onto the mixing pad.  The actual length to be extruded will depend on the volume of dental cement needed which is related to the size and type of restoration to be cemented.  Gently dry the tooth and the surface of the restoration.  Thoroughly mix the pastes for approximately 30 sec.  Spread a thin layer of Temp-Bond NE over all areas that will contact the prepared teeth.  Firmly seat the restoration in the mouth.  After setting time (approx. 2 min. in the mouth), trim away the excess material.  Store at normal room temperature and humidity. 5/6/2023 M.Hosny 14 5/6/2023 M.Hosny 15 Non-Adhesive cement Zinc Phosphate cement 5/6/2023 M.Hosny 16 Zinc Phosphate cement  Properties:  Non-Adhesive.  Irritant to pulp (initial pH 2 which rises over 24 hrs to 5.5).  No anti-cariogenic property.  Good flow but soluble.  Good mechanical properties.  Thin film (20-25μ) thickness.  Opaque: not used to lute translucent ceramic restorations.  Long setting time (good for long span bridges).  Easy removal of excess cement. 5/6/2023 M.Hosny 17 Zinc Phosphate Manipulation  Powder divided into 6 equal parts…added to liquid….on a clean cold glass slab (dissipate heat from exothermic reaction).  Proper mix when there is stringing for 2cm.  Adding powder to increase P/L ratio will: increase mech prop; decrease solubility and irritation.  Should I use a varnish??? 5/6/2023 M.Hosny 18 ZnO ZnO Zn+ ZnO Zn+ 5/6/2023 M.Hosny Zinc aluminophosphate gel 19 Adhesive cement Zinc polycarboxylate cement (Zinc polyacrylate cement) 5/6/2023 M.Hosny 20 Zinc polycarboxylate Properties:  The first adhesive cement (Bond to tooth structure and metal).  More biocompatibility than zinc phosphate cement (Polyacrylic acid have more molecular weight).  Moderate strength/ moderate solubility.  High viscosity (difficult to mix).  Short working time (2.5min).  Residual cement is more difficult to remove.  Maximum film thickness: 25 µm  Opaque: not used to lute translucent ceramic restorations. 5/6/2023 M.Hosny 21 Zinc polycarboxylate  Bonding to tooth structure  Polyacrylic acid is believed to react with calcium ions via the carboxyl group.  The adhesion depends on the unreacted carboxyl group. 5/6/2023 M.Hosny 22 Zinc polycarboxylate  Manipulation  Mix first half of powder to liquid to obtain the maximum length of working time.  Applications  Cement crowns  Used as base  Temporary filling  Lute the stainless steel crown 5/6/2023 M.Hosny 23 5/6/2023 M.Hosny 24 Adhesive cement Glass ionomer cement Or called Polyalkynoate cements Conventional glass ionomer cement Resin-modified glass ionomer cement [RMGICs] Powder + Liquid / Powder + water / Encapsulated 5/6/2023 M.Hosny 25 Glass ionomer cement Composition 5/6/2023 M.Hosny 26 Glass ionomer cement Properties  Film thickness is similar or less than zinc phosphate cement.  Setting time 6 to 8 minutes from start of mixing.  Less pulpal irritation.  Bactericidal or bacteriostatic due to releases fluoride.  Chemical adhesion to enamel and dentin.  Exhibits good biocompatibility.  The 24-hour compressive strength is greater than zinc phosphate cement.  The compressive strength increase to 280 MPa between 24 hours to 1 year after initial setting. 5/6/2023 M.Hosny 27 Glass ionomer cement  Low fracture toughness.  Translucent (used with the porcelain labial margin design).  Sensitive to moisture contamination during setting (protected with resin coat, or a band of cement should be left undisturbed for 10 minutes).  Residual cement is more difficult to remove.  Post-operative sensitivity (actually be result of desiccation or bacterial contamination).  Desensitizing agent may prevent sensitivity, although it may also reduce retention. 5/6/2023 M.Hosny 28 Glass ionomer cement Setting reaction There are three stages: 1- Dissolution 2- Gelation  Calcium ions have more reactivity than aluminum ions.  This is critical phase of contamination. 3- Hardening  Last as long as 7 days.  The reaction of aluminum ions provides the final strength of set cement. 5/6/2023 M.Hosny 29 Adhesive cement Resin modified glass ionomer cement Composition: Powder: same as that for conventional GICs in addition to initiators, such as camphoroquinone.  Liquid: Water-soluble methacrylate-based monomer, replace part of liquid component of conventional GIC. Monomers can be polymerized, chemical or light activation or both.  Contain non-reactive filler particles Lengthens the working time Improves early strength Makes the cement less sensitive to moisture during setting. 5/6/2023 M.Hosny 30 Resin modified glass ionomer cement  Combine some of the desirable properties of glass ionomer (fluoride release and adhesion) with the higher strength and low solubility of resins.  Post cementation sensitivity resulting from their use is minimal.  Indication: Complete metal crowns, MCCs, FPDs, All-alumina or all- zirconia strengthened core ceramic restorations. 5/6/2023 M.Hosny 31 Relative properties of a glass ionomer and a resin-modified GI. cements Property GIC RMGIC Working time 2 min 3 min 45 sec Setting time 4 min 20 sec Compressive strength 202 MPa 242 Mpa Tensile strength 16 Mpa 37 Mpa 5/6/2023 M.Hosny 32 resin cement 5/6/2023 M.Hosny 33 RESIN CEMENTS COMPOSITION  Powder Resin matrix (diacrylate monomer, Bis-GMA, UDMA, TEGDMA) Inorganic fillers – Coupling agent (organo silane) Chemical or photo initiators and activators (Camphorquinone, a tertiary amine, Benzoyl peroxide) Tri-n-butylborane (TBB) as catalyst  Liquid Methyl methacrylate Tertiary amine. 4-META, MDP 5/6/2023 M.Hosny 34 Advantages of Resin Cements 1. Excellent mechanical properties. 2. High bond strength with adhesive properties (capable of bonding chemically to dentin). 3. Low solubility. 4. Translucent and has excellent esthetic with ceramics. 5. Provides high retention, improves marginal adaptation and prevents microleakage. 6. Provides additional reinforcement to both the restoration and the dental tissue because of the effective adhesion achieved at the cement-restoration & cement–dentin interfaces. 5/6/2023 M.Hosny 35 Disadvantages of resin Cements 1. Marginal degradation over time due to wearing of the resin cement. 2. Technique sensitive. 3. Possibility of post-operative sensitivity after total-etch technique. 4. Possible leakage and pulp sensitivity. 5. Polymerization shrinkage. 5/6/2023 M.Hosny 36 resin cement Definitions  Bonded restoration: ceramic restoration bonded with resin cement.  Cemented restoration: ceramic restoration that is mechanically retained (luted) on a standard preparation with cement that does not chemically bond to tooth structure.  Silane Primer (Silane coupling agent): primer based on silane used with silica-based ceramics (feldspathic porcelain, leucitereinforced ceramic, lithium disilicate ceramic).  Ceramic Primer: primer based on acidic adhesive monomers used with alumina based and zirconia-based ceramics.  Ceramic primers may contain silane and metal primers. 5/6/2023 M.Hosny 37 resin cement Types of resin cement Adhesive, esthetic, and self-adhesive resin cements  Adhesive resin cements typically only require a bonding agent for adhesion to tooth structure.  Selected when greater bond strength and stronger mechanical properties of the ceramic and cement are desired.  Esthetic resin cements require a bonding agent for adhesion to tooth structure and a primer for adhesion to ceramic surfaces.  Self-adhesive resin cements have adhesive components that eliminate the need for separate etchants and primers for bonding to tooth structure or M.Hosny zirconia-based ceramics. 5/6/2023 38 resin cement  Characteristics of Adhesive Resin Cements  Primer is needed for bonding to tooth substrates.  Silane coupling agent is needed for silica-based ceramics.  Can bond directly to zirconia without primer.  Curing mode options – can be light-, dual-, or self-cured.  Several shades available.  May release fluoride. 5/6/2023 M.Hosny 39  Characteristics of Esthetic Resin Cements  Self-etch or total-etch bonding agent is needed for bonding to tooth substrates.  Silane or ceramic primer is needed for all-ceramic restorations.  Curing mode options – can be light- or dual-cured.  Light-cured cement is available for veneers.  Stronger mechanical properties than self-adhesive resin cement.  Most esthetic resin cements provide water soluble try-in pastes.  Multiple shades available. 5/6/2023 M.Hosny 40 resin cement  Characteristics of Self-adhesive Resin Cements  Self-etching – no phosphoric acid or special primer needed for bonding to tooth substrates.  Can bond directly to zirconia without primer.  Some products recommend use of a silane primer for porcelain and ceramic primer for zirconia.  Curing mode options – can be light-, dual-, or self-cured.  May release fluoride.  Usually available in universal, translucent and opaque shades. 5/6/2023 M.Hosny 41 5/6/2023 M.Hosny 42 Manipulation of Resin Cements  Esthetic and adhesive resin cements require etching and priming steps.  A silanating agent is required with esthetic resin cements for bonding to silica-based ceramics.  A zirconia primer is required with esthetic resin cements for zirconia bonding.  Most of these dual-cured cements are paste-paste system with auto-mix dispensers.  Self-adhesive resin cements eliminate the etching and priming steps.  Most self-adhesive resin cements are paste-paste systems with auto-mix dispensers, but encapsulated and auto-dispensed products are also available. 5/6/2023 M.Hosny 43 Clinical Tips  Don’t over dry the tooth – moisten with wet cotton pellet, if needed.  Never use light-cure only resin cement with more opaque silicaand zirconia-based ceramic restorations.  Use light-activation whenever possible.  Dual-cured resin cements typically have increased flexural strength and bond strength when activated with a light vs. selfcuring only.  Translucent shades of resin cement may be sensitive to ambient light. 5/6/2023 M.Hosny 44 Clinical Tips  Self-adhesive resin cements are contraindicated where there is not enough tooth retention.  Self-adhesive and adhesive cements containing acidic monomer usually do not require ceramic primer for bonding to zirconia-based restorations.  Esthetic cements require a silane primer for bonding to silicabased ceramics or ceramic primer containing acidic monomer for bonding to zirconia-based ceramics. 5/6/2023 M.Hosny 45 Clinical Tips  For higher bond strength to zirconia based ceramics, sandblast with 50 um alumina and use a ceramic primer or apply a tribochemical silica coating to the restoration and use a silane primer.  Ceramic primers based on acidic adhesive monomers are used with alumina- and zirconia-based ceramics, as an acidic phosphate ester (MDP) in CLEARFIL ceramic primer.  Metal primers based on sulfide methacrylate are used with alloys.  Excess cement is easy to remove after tack curing, but hard to clean up if you light-cure too long. 5/6/2023 M.Hosny 46 5/6/2023 M.Hosny 47 resin cements Classified by Polymerization Mechanism Light cured Chemically cured Dual cured contain photoinitiators (camphoroquinone). Used for veneers. Contain chemical initiators (tertiary amine benzoyl peroxide). Contain both chemical and light initiators E.g. X3 veneer 5/6/2023 E.g. Variolink II. E.g. Panavia 21 M.Hosny 48 Classification by Polymerization Mechanism  Light-Cure Resin Cements:  Utilize photo-initiators, which are activated by light. The ability of light to penetrate all areas and activate the photo-initiators is important with this type of cement.  Advantage:  Increased working time compared to the other cure types.  The clinician has the ability to remove excess cement before curing, and thus the finishing time required is decreased.  Color stability compared to dual-cure or chemical-cure resin cements.  Uses: Esthetic restorations and metal-free restorations. Also recommended when cementing thin and fairly translucent ceramic. 5/6/2023 M.Hosny 49 Classification by Polymerization Mechanism Light-Cure Resin Cements  Examples of light-polymerized cements: RelyX™ Veneer Cement and Variolink® Veneer 5/6/2023 M.Hosny 50 Classification by Polymerization Mechanism  Chemical-Cure Resin Cements  Polymerize with a chemical reaction and are referred to as “self-curing.” This means that two materials must be mixed together to initiate this reaction.  Uses: In areas where light-curing is difficult. Like metal restorations, endodontic posts, and ceramic restorations.  Examples: PANAVIA F 2.0 Opaque™ (Kuraray Dental; and C&B™ Cement (BISCO, Inc.). 5/6/2023 M.Hosny 51 Classification by Polymerization Mechanism Chemical-Cure Resin Cements 5/6/2023 M.Hosny 52 Classification by Polymerization Mechanism  Dual-Cure Resin Cements  Dual-cure resin cements are capable of being cured by means of both chemicals and light.  Indicated: when the ceramic is too thick or too opaque to allow transmission of light through it.  Examples: NX3 Nexus® Third Generation, RelyX™ ultimate Adhesive Resin Cement(3M ESPE); and Multilink Automix (Ivoclar Vivadent Inc.). 5/6/2023 M.Hosny 53 Classification by Polymerization Mechanism Dual-Cure Resin Cements 5/6/2023 M.Hosny 54 Classification by Polymerization Mechanism 5/6/2023 M.Hosny 55 Classification by Adhesive Scheme Total-etch, self-etching, and self- adhesive.  Total-Etch Resin Cements  Total-etch resin cements use a 30% to 40% phosphoric acid-etch to etch dentin and enamel. This etching procedure removes the smear layer, and dentinal tubules are opened.  After etching, the adhesive is then applied to the preparation to bond the cement to the tooth.  These cements and the adhesives used with them can be light- or dual-cured.  Total-etch resin cements have increased the bond strengths of resinbased cements to nearly that of enamel bonding and have significantly reduced micro leakage. 5/6/2023 M.Hosny 56 Total-Etch Resin Cements  Advantage: Provides the highest cement-to-tooth bond.  Disadvantage: This multi-step application technique is complex and consequently might compromise bonding effectiveness, because each step represents a possible contamination point.  Examples: RelyX ARC (3M ESPE); Variolink II (Ivoclar Vivadent Inc.) 5/6/2023 M.Hosny 57 Classification by Adhesive Scheme  Self-Etch Resin Cements  Self-etch systems apply a self-etching primer to prepare the tooth surface, and mixed cement is applied over the primer.  Advantage:  Eliminate steps during application with the goal of reducing operator errors and technique sensitivity and increasing ease of use.  Disadvantage: Bond strength to enamel that is weaker than that of total-etch systems. 5/6/2023 M.Hosny 58 Self-Etch Resin Cements Examples: ResiCem (shofu), PANAVIA F 2.0 (Kuraray Dental). 5/6/2023 M.Hosny 59 Classification by Adhesive Scheme  Self-Adhesive Resin Cements  A number of resin cements have been introduced as one-component “Universal adhesive cements”; they are said to have good bond strengths to dentin, enamel, and porcelains without the need for separate bonding agents.  Can bond to an untreated tooth surface that has not been micro-abraded or pretreated with an etchant, primer, or bonding agent; thus, cementation is accomplished in a single step.  These cements contain phosphoric acid, which is grafted into the resin.  Once mixing is initiated, the phosphoric acid reacts with filler particles and dentin in the presence of water, forming a bond.  The resin is polymerized into a cross-linked polymer, as the case with composite resin bonding. 5/6/2023 M.Hosny 60 Self-Adhesive Resin Cements The efficiency by which the self-adhesive resin cements adapt to and seal margins is critical for their success. Because self-adhesive cements bond to tooth structure, excess cement should be removed before setting to avoid damaging the weaker early bond. Self-adhesive cements are dual-cured, and like all dual- cured cements, have reduced bond strengths, color stability, and wear resistance. Examples: RelyX™ Unicem (3M ESPE), SpeedCEM™ (Ivoclar Vivadent Inc.). 5/6/2023 M.Hosny 61 Classification by Adhesive Scheme 5/6/2023 M.Hosny 62 Comparable properties of cements 5/6/2023 M.Hosny 63 Compressive strength [MPa] en t m ce Re sin RM G IC IC G yl bo x ar lyc Po Zi nc ph os ph a at e te 160 140 120 100 80 60 40 20 0 Zhen Chun Li and Shane N. White, 1999 5/6/2023 M.Hosny 64 Bond strength Separation forces [MPa] Sule Ergin and Deniz Gemalmaz, 2002 5/6/2023 M.Hosny 65 Film thickness [µm] n Re si GI C RM GI C yla bo x ar lyc Po Zi nc ph os ph a te te 50 45 40 35 30 25 20 15 10 5 0 Shane N. White, Zhaokun Yu, 1992 5/6/2023 M.Hosny 66 Solubility ZOE > Polycarboxylate > Zinc phosphate ~ GIC > Resin cement Irritation to pulp tissues Resin ~ Zinc phosphate > GIC > Polycarboxylate > ZOE 5/6/2023 M.Hosny 67 Cementation of long span bridges *Cement requirements: 1. Long working time. 2. High mechanical properties. 3. Preferably to be adhesive. *Cements of choice: 1)Glass Ionomer. 2)R.M.G.I 3)Zinc Phosphate. 4)Adhesive resin cement. (Panavia with controlled setting time) N.B:- Zinc Polycarboxylate cements are not used due to its extremely short working time. ZnO eugenol cements are not used due to their low mechanical properties and short working time. 5/6/2023 M.Hosny 68 Cementation in caries active patients *Cement requirement: Must have anticariogenic effect by releasing fluoride ions and inhibiting secondary caries. *Cements of choice: 1. Glass Ionomer. 2. Resin modified Glass Ionomer. 3. Composite resin releasing fluoride. (e.g Panavia F) 5/6/2023 M.Hosny 69 Cementation to deep preparations *Cement requirement: Should be non irritant and palliative to the pulp. *Cement of choice: 1. Zinc Polycarboxylate. 2. Zinc oxide eugenol. 5/6/2023 M.Hosny 70 Post crowns cementation *Cement requirements: 1. High flow. 2. High strength properties. *Cements of choice (according to post material): I- Metallic post 1. Resin modified Glass Ionomer. 2. Glass Ionomer. 3. Zinc Phosphate. II- Non metallic post Adhesive resin cement. 5/6/2023 M.Hosny 71 Cementation to core based materials *Cement requirements: Adhesion to the core material. *Cements of choice: (According to core material type) 1. Amalgam core: All currently used cements can be used. 2. Composite resin core: Composite resin cement. 3. Glass Ionomer core: Glass Ionomer or R.M.G.I cement. 5/6/2023 M.Hosny 72 Cementation to questionable preparations *Cement requirements: 1. Adhesive. 2. Extremely high mechanical properties. 3. Insoluble. *Cement of choice: Adhesive composite resin cement with pulp protection over very deep preparations. 5/6/2023 M.Hosny 73 Cementation of Ceramic Laminate veneers *Cement requirements: 1. Translucent. 2. Adhesive to tooth and porcelain. 3. Early high mechanical strength and fracture toughness. *Cements of choice: Adhesive resin cement. N.B Glass Ionomer cement although it is translucent but has the disadvantage of slowness with which ultimate properties are developed. So when subjected to masticatory stress elastic deformation of the underlying cement could result in fracture of the brittle ceramic. 5/6/2023 M.Hosny 74 Cementation Procedures for glass ceramics Adhesive cementation Etches surface with 9-10 % a hydrofluoric acid, for approximately one minute for Leucite reinforced ceramics (Empress I) & 20 sec. for Lithium disilicate glass ceramics (E-max.) Silane placed over etched surface to increase the wettability and to interact chemically with both the resin and ceramic. Adhesive system, followed by application of a resin cement Resin cements are polymerized via light, chemicals or a dual. 5/6/2023 M.Hosny 75 5/6/2023 M.Hosny 76 5/6/2023 M.Hosny 77 Polycrystalline ceramics  Zirconia-based ceramics with ideal retention can be cemented with traditional crown and bridge cements if retention is favorable or bonded with resin cements.  Zirconia is a non-silica-based ceramic and thus doesn’t etch using traditional methods.  Retention of zirconia-based ceramic restorations depends on mechanical roughening of the surface by air-particle abrasion (50 to 60 μm at 0.2 MPa for 5 seconds) and chemical bonding with adhesive monomer in special primers or resin cements. 5/6/2023 M.Hosny 78 Polycrystalline ceramics  An acidic adhesive monomer such as 10-methacryloyloxydecyl dihydrogen phosphate (MDP) bonds to zirconia-based ceramics.  This monomer has two functional groups: one phosphate group which is responsible for bonding to the hydroxyl group on the zirconia surface and one carboxylic acid group which is bonded to composite resin.  These three steps of Airborne particle abrasion, Primer application, and Composite resin luting agents (the “APC Concept”) are now a standard protocol for zirconia bonding.  Tribochemical silica application followed by application of an adhesion-promoting agent to increase the bond strength of resin cements. 5/6/2023 M.Hosny 79 Polycrystalline ceramics  Saliva, phosphoric acid, or blood contamination can adversely affect the bond strength.  Primer application should be done after intraoral evaluation and decontamination of the crown.  Decontamination could be done by applying 5% NaOCl, alcohol, or Ivoclean (Ivoclar AG, Amherst, NY) followed by water rinsing and air drying. 5/6/2023 M.Hosny 80 5/6/2023 M.Hosny 81 5/6/2023 M.Hosny 82 5/6/2023 M.Hosny 83 5/6/2023 M.Hosny 84 5/6/2023 M.Hosny 85 5/6/2023 M.Hosny 86 Any Questions REFERENCES Contemporary fixed prosthodontics, (6th edition) Luting Agents and Cementation Procedures, Page 851 5/6/2023 M.Hosny 87 THANK YOU 5/6/2023 M.Hosny 88