TARGIS/VECTRIS.

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Presentation transcript:

TARGIS/VECTRIS

Materials with very different physical properties are used in the conventional crown and bridge technique. The thermal and elastic properties are the most important ones to observe. Metal alloys are most often used for frameworks. These materials, however, cannot always be used, since they are biologically incompatible and they compromise the aesthetics of the restorations. In addition, metal veneered restorations are complex systems with a number of interfaces between a variety of materials. These areas are the potentially weak points of the restoration and are often the cause of clinical failure.

Tension in materials Materials expand when heated. When their are left to cool, they take on their original dimensions. The degree of this behaviour differs from one material to the other. It is represented by the particular coefficient of thermal expansion (CTE). The CTEs of conventional crown and bridge materials are listed in the table. The difference between the CTEs of metals and resins is considerably greater than that between metals and ceramics. Metal-ceramics are exposed to high temperatures during the production procedure. Lightcuring veneering composites, however, are only exposed to then-nocycles when they come in contact with foods with different temperatures. Despite the use of special adhesive systems that produce a bond between metals and resins, chipping off of the material is often observed.

Materials demonstrate different degrees of deformation when subjected to load. Their particular trend to deformation is determined with the modulus of elasticity. Metals also clearly differ from popular veneering materials in this respect. As a result, tension is produced in the interface areas when load is applied. This tension can cause the bond to fail. In contrast to metal, the CTE and modulus of elasticity of the new Vectris framework material is coordinated with the new Targis complete veneer material. Furthermore, the properties of this material correspond to those of human dentin. As a result, tension is minimized in teeth restored with this system

Material CTE (20-60-C) Modulus of elasticity [ttm/(-*K)] [N/mm2] Conventional veneering resins 40 2 - 20'000 Veneering ceramics 6 - 12 50 - 70'000 Dental alloys 10 - 14 200'000 Tarais (Dentin) 40 12'300 Vectris (Single) 24 2 l'000 Vectris (Pontic) 6 (Iangs)/51 ( quer) 36'000 Human Dentin 7 - 9 16 - 18'000

Aesthetics Special shoulder materials and opaquers considerably improve the aesthetic properties of metal restorations. However, there is no technique that can compensate for the opacity of these restorations. The new tooth-coloured, translucent, highly aesthetic Vectris framework material offers optimum prerequisites for true-to-nature restorations.

Vectris fibre-reinforced material Fibre-reinforced technology is being used in various industries (e.g. aeronautical and shipbuilding industries). The material is used in situations where permanent loads are applied and light weight is required. Vectris is a fibre-reinforced material used to fabricate metal-free, translucent frameworks for crowns and bridges. The fibres and the matrix of the material have different basic physical properties. The fibres demonstrate high tensile strength, a high tensile modulus, and low shear strength, while the matrix demonstrates a higher degree of toughness.

An optimum composite material should combine the favourable properties of both components to form a material that is superior to the components themselves. This goal is achieved by optimizing the fibre-matrix bond. This bond is achieved chemically. The glass surface demonstrating silanol groups is conditioned with silane. In the processes of condensing on the glass surface, the silane produces a covalent bond. In turn, the silane contains a functional methacrylate group which copolymerizes with the methacrylate of the matrix. Consequently, a chemical bond is achieved between the matrix and the fibres.

Surface conditioning Mixing itioned fib Matrix F- Surface conditioning Mixing itioned fib Matrix F- lamination M> Vectris Pontic PR> Vectris Single M> Vectris Frame Pressing and curing Eg> Vectris VS-1 Finished product M> Fibre reinforced composite

Veneering material Targis The veneering material is visible and comes in contact with adjacent and antagonist teeth. Therefore, the properties of the veneering material are decisive for the surface quality and the aesthetic effect of restorations, as well as for their interaction with the surrounding teeth and gingiva. Targis is a highly filled (up to 75-85% inorganic fillers) material. The high content of fillers provides aesthetic properties similar to those of ceramics, while the organic matrix assures the ease and accuracy of processing of resin materials. The matrix is formed upon polymerization of monomeres (chemical bond via free double bonds) and the filter particles are chemically linked via silane to the matrix'. The wear resistance has been coordinated with that of natural enamel to protect antagonists. Furthermore, the Targis/Vectris Systems allows gentle preparation of teeth. Preparation margins may be supergingival. Furthermore, bridges anchored by inlays are possible.

Tempering (final curing) Once restorations have been fabricated, they are tempered in the Targis Power. During this controlled process involving heat and light, the properties of the materials are optimized (stability in mouth, colour stability, wear resistance, adhesion of plaque).

Bond The followig materials are bonded in dentistry and dental technology: resin - resin metal - resin metal - ceramic ceramic- resin resin - enamel and dentin Based on the content of organic molecules in Targis and Vectris resin-resin bond is found. Due to the high content of inorganic part in Vectris (fiber) and Targis (filler) also the resinceramic and when Targis is used on metall the metal-resin bond must be considered.

1.6.1. Resin-resin bond Light-curing resins establish a real chemical bond between different layers. This bond is promoted by the very thin surface layer that does not thoroughly cure during exposure to light, since ambient oxygen in these layers inhibits polymerization (Janda, 1992). The free methacrylates contained in this layer chemically react with the monomers of the applied resin. Consequently, a strong, durable chemical bond forms between the layers. This reaction is effectively utilized during the layering of the Targis material. During this procedure intermediate curing is possible. The same is valid for the layering of direct composite restorations. This bonding mechanism also plays an important part in light-curing Targis restorations (inlays, onlays and anterior crowns) and restorations supported by Vectris (posterior crowns and bridges). This reaction alone mediates a chemical bond between Targis/Vectris restorations and luting composites.

1.6.2. Resin-nietal bond For decades, research has been conducted in the field of dental lab technology with the objective of creating a bond between metals and resins, which would be resistant to the oral environment. Two issues, however, have not been solved: 1. After only a short time in the mouth, discolouration is visible between the metal and the resin. As a result, the aesthetic quality of the work is compromised.

2. Relatively large retentive elements have to be included in the metal framework to support the resin. Consequently, thicker layers of the veneering resin have to be applied to successfully mask these elements. In the past few years, systems that permit a durable bond between metals and resins have been developed (Silicoaterl&, Rocatec, OVS, Spectra Link). All these systems involve the conditioning of the substrate (metal) to produce bifunctional molecules that adhere to the metal surface (often silane) and that contain a polymerizable double bond. These molecules react with the methacrylate groups contained in the monomers of the applied resin in a radical polymerization process.

Targis Link is a bonding agent based on phosphoric acid ester with a methacrylate function. The phosphoric acid ester group of the molecule is a strong acid that reacts with the metal or the metal oxides' and forms a phosphate. This compound forms passivation layers on the metal surface. After the reaction with the metal oxide, the layer is inert. The methacrylate group in the phosphoric acid reacts with the monomer contained in the Targis Opaquer and forms a copolymer. As a result, a bond with the veneering material is assured. The hydrolytic stability (insensitivity towards moisture) is achieved, since Targis Link contains a monomer with aliphatic hydrocarbon that is highly water-repellent.

1.63. Vectiris-Targis bond The Vectris-Targis bond is basically a resin-resin bond. However, the oxygen inhibited layer is very thin as a result of the foil covering (Therefore, the number of free double bonds is low.). Furthermore, the thin inhibited layer is removed when the framework is ground. Consequently, the finished Vectris frameworks are silanized (Targis Wetting Agent). The silane condenses on the surface of the exposed fibres and bonds with the monomers of the Targis veneering material with the help of the methacrylate groups (resin-ceramic bond). The bond Vectris-Targis is therefore based on two mechanisms: 1. bond matrix Vectris - matrix Targis 2. fiber Vectris- silan - matrix Targis

1. 7. Competitive materials 1. 7. 1 1.7. Competitive materials 1.7.1. Vectiris Vectris is unmatched in the dental industry. The material and the procedures have been developed specifically for dental applications. As a result, there are no real competitors. Vectris can be used for the same indications as metal frameworks and the "core" materials from all-ceramic systems (In-Ceram, Dicor, Optec, IPS Empress).

1. 7.2. Targis Targis is classified as belonging to the following types ofmaterials (Touati, 1996): - Second-generation laboratory composites - Ceramic polymers - Polyglasses - Ceromers

These materials are: -. highly filled (mineral fillers); - These materials are: - highly filled (mineral fillers); - demonstrate improved physical and mechanical properties; - mediate an excellent bond with metals.

Distinguishing features: - Distinguishing features: - Easy processing (photo polymerisation and tempering) - Improved flexural strength - Increased elasticity and reduced susceptibility to fracture (resilience) - More freedom in preparation - Reduced risk of fracture during try-in - Easy surface conditioning prior to cementation (sandblasting without hydrofluoric acid etching)

Filler Flexural Modulus of wt/wt strength elasticity [MPal [MPal Artglass (Kulzer) 72 120 91000 Conquest (Jeneric Pentron) 79 155 8'500 Columbus (Cendres et Metaux) 77 160 12'000 Targis (Ivoclar) 80 150-160 10,000 BelleGlass HP (Belle de St. Claire) 74 150 9'655 Touati, 1996

This document addresses the following aspects of the new TargisNectris System: - Composition - Physical properties - Studies on the material (in vitro) - Clinical investigations (in vivo) - Toxicological data - Literature references

2. Technical data sheets TECHNICAL DATA SHEET IVCCLAR Product: 2. Technical data sheets TECHNICAL DATA SHEET IVCCLAR Product: TARGIS DENTIN Type of material: Veneering material Standard - C omposition: (Specification in @eight %) is-GMA 9.0 Decandiol dimethacrylate 4.8 Urethane dimethacrylate 9.3 Bariumglassfiller, silanized 46.2 Mixed oxide, silanized 18.2 High dispersed silica 11.8 Catalysts and Stabilizers 0.6 Pigments 0.1

Physical properties In accordance with ISO 10477 - Dentistry - Polymer based crown and bridge materials Flexural strength 170 + 20 MPa Flexural modulus 12300+ 900 MPa Ball indentation (36.5/30) 560 + 40 MPa Vickers hardness (HV 0.2/30) 640 + 60 MPa Water absorption 16.5 + 1.2 tig/mm' Water solubility 2.0 + 0.8 Ag/MM3 Depth of cure >- 2 mm Consistency (Penetrometer) 3 + 0.2 mm Filler content 76.2 weight % 55.9 volume %

R+D / Scientific Service. Visa:. P. Oehri R+D / Scientific Service Visa: P. Oehri Date of issue / Reference: April 1997 - PO Ima T-DENT-E.DOC Replaces version of- February 1996

TECHNICAL DATA SHEET IVCCIAR Product: TARGIS INCISAL Type of material: Veneering material Standard - Composition: (Specifictation in weight %) Bis-GMA 8.7 Decandiol dimethacrylate 4.6 Urethane dimethacrylate 9.0 Bariumglassfiller, silanized 72.0 High dispersed silica 5.0 Catalysts and Stabilizers 0.6 Pigments 0.1

Phvsical Properties: In accordance to ISO 10477 - Dentistry - Polymer based crown and bridge materials Flexural strength 200 + 20 MPa Flexural modulus 11000 + 1200 MPa Ball indentation (36.5/30) 640 + 30 MlPa Vickers hardness (HV 0.2/30) 700 + 60 MPa Water absorption 16.5 + 1.2 jig/nun3 Water solubility 2.0 + 0.8 pg/mm' Depth of cure >- 2 mm Consistency (Penetrometer) 3 + 0.2 mm Filler content 77.0 weight % 55.5 volume %

R+D / Scientific Service. Visa:. P. Oehri R+D / Scientific Service Visa: P. Oehri Date of issue / Reference: April 1997 - PO Inia T-SCHN-E.DOC Replaces version of: February 1996

TECHNICAL DATA SHEET IVCCLAR Product: TECHNICAL DATA SHEET IVCCLAR Product: VECTRIS SINGLE, FRAME, PONTIC Type of material: Fibre reinforced metal-free frame work material for the veneering technique

Standard - Composition: (Specificati. n in weight %). Single. Frame Standard - Composition: (Specificati.n in weight %) Single Frame Pontic Bis-GMA 38.6 35.2 24.5 Decandiol dimethacrylate 0.5 0.4 0.3 Triethyleneglycol dimethacrylatr 9.7 8.8 6.2 Urethane dimethacr-ylate 0.1 0.1 0.1 High dispersed silica 5.5 5.0 3.5 Catalysts and Stabilizers < 0.5 < 0.4 < 0.3 Pigments < 0.1 < 0.1 < 0.1 Glass fibres 45.0 50.0 65.0 Physical properties: In accordance to ISO 10477 - Dentistry - Polymer based crown and bridge materials Single Frame Pontic Flexural strength [Mpa] 700 + 70 700 + 70 1300 + 60 Flexural modulus [MPa] 21000 + 1800 21000 + 1800 36000 +2500 Water absorption [mpg/mm'] 18.8 + 0.8 18.8 + 0.8 --- Water solubility [mpg/mm'] 0.8 + 0.25 0.8 + 0.25 --- R+D / Scientific Service Visa: P. Oehri Date of issue / Reference: April 199 7 - PO Ima V-SPF-E.DOC Replaces version of: May 1996 Scientific Documentation Targis/Vectis Page 13 of3l

3. Physical properties. Material. Flexural. Modulus of. Water. Water 3. Physical properties Material Flexural Modulus of Water Water Curing strength elasticity absorption solubility depth [N/mm'] [N/mm'] lttg/mm'] [fig/mm,] [MM] Targis Dentin 170 _ 20 12'300 900 16.5 _ 1.2 2.0 _ 0.8 2 Targis Incisal 200 _ 20 1 l'OOO 1200 16.5 _ 1.2 2.0 _ 0.8 2 Targis Base 145 _ 15 6'000 500 27.8 _ 0.9 < 5 >- 1.5 Targis Gingiva 200 _ 20 11,000 1200 16.5 _ 1.2 2.0 _ 0.8 >- 2 Targis Molar Incisal 200 _ 20 1 l'OOO 1200 16.5 _ 1.2 2.0 _ 0.8 2 Targis Occlusal Dentin 170 _ 20 12'300 1000 16.5 _ 1.2 2.0 _ 0.8 2 Targis Transparent 200 _ 20 1 l'OOO 1200 16.5 _ 1.2 2.0 _ 0.8 2 Vectris Single 700 _ 70 2l'OOO 1800 18.8 _ 0.8 0.8 _ 0.25 Vectris Pontic 1300_ 60 36'000 2500 Vectris Frame 700 _ 70 2l'OOO 1800 18.8 _ 0.8 0.8 _ 0.25 Vectris Glue 140 _ 20 7-600 300 In-house test, R&D Ivoclar Schaan Scientific Documentation Targis/Vectis page 14 of 31

4. Studies on the material (in vitro) 4. 1 4. Studies on the material (in vitro) 4.1. Shear strength of TargisNectris in combination with various cements Experimental: Test discs were produced of Targis, Vectris and Base No. 1. These discs were conditioned according to various methods. Subsequently, test cylinders were bonded to the discs. After 24 hours the cylinders were sheared off. Results: Material Bonding agent Cement Curing Shear strength Type of fracture after 24h [MPa] Vectrisl Mo.obo.d S Variolik self-curing 21.6 _ 3.4 cohe ive Vect,is dual-curing 23.5 _ 4.1 cohe:ive Vectris 1'.ght-curing 22.9 _ 5.8 cohesive Vectris Vectris2 Monobond S Dual Cement dual-curi.g 22.9 _ 3.5 cohesive Vectris self-c.ring 20.3 _ 3.8 cohesive Vectris Ve,!trisl Monobond S Vivaglass Line, dual-curing 14.0 _ 3.0 cohesive/adhesive in pat, cement fracture Ve,!tri!; 2 Mon.bond S Advance (DeTr@y) self-curing 14.9 _ 2.0 cohesive Vectis Vectrisl Monobo.d S Phosphacap self-curing no adhesion Vectris 2 Monobond S Vivaglass Ce. self-curing no adhesion Vectrisl, 4 Monobond S Variolink self-curing 23.3 _ 4.2 cohesive Vectris dual-curing 23.1 _ 3.8 cohesive Vectris light-curing 21.6 _ 4.4 cohesive Vectris Targis Denti.3, 1 Mo.obond S Variolink dual-curing 22.3 _ 6.3 cohesive Targis light-curing 16.1 _ 7.8 cohesive Targis Targis Dentin3, I Monobond S Dal Cement dual-curing 22.1 _ 8.2 cohesive Targ@s self-curing 9.16.4 cohesive/adhesive Targis Denti.3, I Mo.obond S Vivaglass Liner dual-curing 16.4 3.3 cohesive Tagis T.,gis D@nti.3, 1 Monobond S Advance (DeTrey) dual-curing 12.1 3.3 cohesive/adhesive Base No. 13, 2 Monobond S Variolink d.al-curing 41.4 14.4 cohesive Base light-,curing 31.3 16.3 cohesive Base Base No. 13, 2 Mo.obond S Dual Cement dual-curing 22.7 _ 11 cohesive Base self-curing 33.3 _ 9.6 cohesive Base Base N.. 13, 2 Mo.obo.d S Advance (DeTrey) self-curing 14.8 _ 4.4 coh s@ve/adhesive Base clear3, 1 Monob.nd S Va,iolink d.al-curing 30.4 _

7. 7. cohesive Base In-house test. R&D Ivoclar Scha. n Discussion: 7.7 cohesive Base In-house test. R&D Ivoclar Scha.n Discussion: The shear strength of 20-30 MPa registered for Variolink and Dual Cement on Targis Dentin, Targis Base and Vectris is very high. The specimens demonstrate a cohesive fracture, that is, the substrates of Dentin, Base and Vectris broke rather than the bond. I ground (lvomill) 3 Targis Pover Program 1 2 sandblasted 4 5 min. saliva; r'@nse; 60 sec. Email Prepaatr Scientif,c Documentation Tagis/Vectris Pge 15 of3l The light-curing glass ionomer cement Vivaglass Liner as well as the hybrid ionomer cement Advance (De Trey) demonstrated considerably lower bond strengths of approx. 15 MPa compared with composite cements. Some adhesive fractures were also noted. Phosphacap and the self-curing glass ionomer cement Vivaglass Cem failed to mediate adhesion. Adhesive luting with a composite cement gives best bond to Targis Base' and Vectris and is therefor recommended.

4. 2. Bonding tests with Targis Link 4. 2. 1 4.2. Bonding tests with Targis Link 4.2.1. Shear- strength: Long-term test following immersion in water Experimental: The metal was ground while wet (I 000 grit SiC paper) and then sandblasted using Special Jet Medium and 4 bar pressure. After having been dried, the metal was coated with Targis Link and two layers of Targis Opaquer (polymerized twice). The inhibited layer was removed with an acrylic sponge and a Targis Dentin cylinder was grafted to the surface. The shear strength was determined with a mechanical testing machine (Zwick). Results: Duration of Wiron 88 Aurofluid 3 Titan Aquarius PaHiag M immersion in IMPal [MPa] [MPal [MPal [MPal Water [37'C] 1 day 17.3 _ 3.5 17.8 _ 5.7 16.9 _ 4.9 9.9 _ 1.8 10.5 _ 3.0 1 week 14.7 _ 5.7 17.1 _ 2.8 17.6 _ 7.5 11 _ 1.5 13.1 _ 3.5 1 month 14.2 _ 2.9 14.5 _ 2.1 16.5 _ 4.6 8.8 _ 2.3 15.4 _ 4.6 3 months 11.6 _ 1.7 16.5 _ 2.1 15.3 _ 4.1 9.8 _ 4.1 14.8 _ 1.5 6 months 14.0 _ 4.7 18.1 _ 2.6 15.9 _ 4.1 9.3 _ 1.2 17.9 _ 3.2 12 months 11.7 _ 1.5 17.4 _ 3.4 14.3 _ 1.8 9.4 _ 2.6 12.5 _ 3.2 In-house test, R&D Ivocla, Schaan Discussion: The Targis Link bonding agent mediated a sound, hydrolytically stable bond to the metal. The strength of the bond depends on the alloy used. The weak bond to Aquarius (86% Au, I 1% Pt) and Palliag M (58% Ag) is explained by the composition of the alloys. Both alloys do not correspond to the recommendations for Targis: Gold, palladium and platinum < 90 % Copper and/or silver <50% 3Targis Base is the base for all Targis restorations. Targis Base is less filled than Targis Enamel and Targis Dentin. Hence it contains more polymerizable monomers, which results in a better bond. Scientific Documentation Targis/Vectris Page 16 of 3 1

4. 2. 2. Flexure-shear test according to Schwickerath Experimental: 4.2.2. Flexure-shear test according to Schwickerath Experimental: The flexure-shear test was first described by Schwickerath (1980). Schwarz et al. (I 992) modified this method to evaluate resin-metal bonds. Results: 80 70.1 72.95 70 67-- 60 7, 50 46.4 4 42 38.6 40 40 -a-7.7 34.5 30 0 2 0 Est@tic.r Vision Neocst 3 Pr.tor 3 Naovhite (All.ys) Columbus Artglass-Kevloc Targis-Targ'@s Lik Allemend M., Cend,es & M6tau. Discussion: Of the systems studied, Targis in combination with Targis Link demonstrates by far the best bond on three different alloys.

4. 3. Tempering (final curing) 4. 3. 1 4.3. Tempering (final curing) 4.3.1. Effects ofthe tempering time on the physical properties Results: Tempering Flexural Modulus of Extension of Ball Vickers time strength elasticity outer fibres hardness hardness [Min] [MPal [MPa] 1%] [MPaj [MPa] 0 115 _ 11 7302_ 666 2.1 _ 0.3 248 8 363 14 3 160 _ 23 9587_ 575 2.0 _ 0.4 509 36 558 5 5 166 _ 14 9902_ 603 1.9 _ 0.3 337 41 937 70 10 154 _ 19 9742 _ 480 1.9 _ 0.3 375 31 956 70 15 151 _ 24 9851 _ 699 1.8 _ 0.3 444 1-5 941 22 31 178 _ 33 10800_ 695 2.0 _ 0.5 412 45 685 37 Targ'is Dentin, in-house tests, R&D Ivoclar Schaan Scientific Documentation Targis/Vectris Page 17 of 31 Discussion: The maximum flexural strength and ball hardness are achieved as early as after three minutes of tempering.

4.3.2. Effects ofthe tempering time on the bond with cements Results: Material Bonding agent Ceme.t Tempering Shea,st,,ength Typeoffracture Variolink after 24h [MPa] Targis Dentin 1, 2 Monobo.d S dual-cu.'ng tempered 2x 14.57.7 cohesive Dent' dual-,!u,i.g tempered 3x 9.6 3.2 cohesive, Dentin dual-cu,i.g tempered 4. 8.4 5.7 cohesive Dentin Targis Base 1, 2 Mo.obo.d S dual-curing tempered 2x 29.0 16.5 cohesive Base d.al-cu,ing tempered 3. 16.7 _ 7.9 cohesive Base du.1-curi.g tempered 4x 24.4 _ 7.1 cohesive Base In.-house test, R&D Ivocla, Schaan Discussion: The bond strength between Variolink and Dentin and Base diminishes with increased tempering of the Dentin and Base materials. The use of Targis Base produces higher bond strengths and hence better marginal seal compared with Targis Dentin. Therefore, Targis Base should be used in the area facing the cement. 2 sandblasted 3 Targis Power Program 2 Scientific Document Targis/Vectris Page 18 of 31

4. 4. Wear in the masticatory simulator Experimental: 4.4. Wear in the masticatory simulator Experimental: The materials were subjected to a combined stress test that consisted of toothbrush and toothpaste wear, rapid temperature changes, and cyclical occlusal stress (antagonist of natural enamel). The five-year values correspond to 300 minutes of brushing teeth, 1,200,000 masticatory cycles (49 N 1.7 Hz), and 3000 then-nal cycles (5 - 55 'C). Results: 160 140 - 120- E 100- 806040- 20-1 5 0 - 5 0.5 [Annual equivalents] In-house test, R&D I,ocla,, S,2h,,a. cco,ding to Y,,ajzi et al., 1990 Discussion: Tragis demonstrates the lowest abrasion of the materials examined. The abrasion values measured are comparable to those of natural enamel. This property is necessary for asstiring a stable occlusion and for preserving the antagonists. Scientfic Documentation Targis/Vectris Page 19 of 3 1

4.5. Compliance of Targis Dentin, Incisal, and Base with ISO standards Targis can be classified as a composite material that must comply with the requirements of ISO 10477 (Dentistry - Polymer-based crown and bridge materials). ISO 10477 Dentin Incisal Base Curing depth 1%] > 70 110: 94 95 85 120: 80 Flexural strength [MPa] > 50 170 _ 20 200 _ 20 145 _ 15 Water absorption [pg/mm'] <32 16.5 _ 1.2 16.5 _ 1.2 27.8 _ 0.9 Water solubility [@ig/mm'] < 5 2.0 _ 0.8 2.0 _ 0.8 < 5 Shade, translucency shade sample fulfilled fulfilled fulfilled Stability of shade 24h / fulfilled fulfilled fulfilled 150,000 lux' In-house test. R&D I,ocla,, Schaan Summary: Targis Dentin, Incisal, and Base comply with ISO 10477.

4. 6. Comparison of Targis with competitive materials 4. 6. 1 4.6. Comparison of Targis with competitive materials 4.6.1. Water absoiptioii according to ISO 10477 1.8 1.6 1.4 1.2 0.8 0.6 0.4 0 ? 0 A,tglass S.1'.d@@ Th@rm.,es'@. 1-c,o. PE Ta,gis LC 11 lc'.s.1 Denti. Institute for dental material science and technology (Institut fur zahnarztliche Werkstoffkunde nnd Technologie), University of Mainz 5 No isible change in shade Scientific Documentation Targis/Vectris Page 20 of 3 1

4.6.2. Flexural strength according to ISO 10477 200 180 160 140 120 100 80 -- - ------4 6 0 40 20 _ Atglass Conq.est Sol'@de. Tbe,mor@si. locro. PE T,,rgis LC H Incisal IM Dentin Institute for dental material science and technology (Institut fur zahnarztliche Werkstoffkunde und Technologie), University of Mainz

4.63. Modulus of elasticity according to ISO 10477 12000 10000 8000 6000 4000 2000 _ Artgl@ss Conquest Solide,, The,.o,esi. 1-cro. PE Targ'@s LC 11 Mcisal F, Dentin Institute for dental material science and technology (Institut fur zahnarztliche Werkstoffkunde und Technologie), University of Mainz Scientific Docuementation Targis/Vectis Page 21 of 31

4.6.4. Depth of cure according to ISO 4049 7 6 5 4 3 2 0 Artglass Coquest Solide. The,moresin Ta,gis LC 11 Incisal IM Dentin Institute for dental material science and technology (Institut fur zahnartliche Wekstoffkunde und Technologie), University of Mainz Scientific Documentation Targis/Vectris Page 22 of 31

5. Clinical investigations (in vivo) 5. 1 5. Clinical investigations (in vivo) 5.1. Targis inlays /onlays Head of study: Prof. F. Lampert, Dr. C. Kuntze, Dr. D van Gogswaardt Clinic for Operative Dentistry, Periodontology, and Preventive Dentistry, R.W.T.H. Aachen, Germany Subj ect: Clinical testing of Targis for onlays bonded with the adhesive technique (partial crowns). In this clinical investigation, - patients between 18 and 65 years - who require 1-3 restorations in premolars or molars are examined. Experimental:Following preparation, impressions are taken of the teeth (no liners/bases are placed). The lab-fabricated onlays are inserted with the adhesive technique using Syntac ("total etch technique") and Variolink. After 6, 12, 24 and 48 months the restorations are examined according to the Ryge criteria (I 9 80). Impressions are taken for the SEM examinations. Status: By January 1996, patients had been provided with 52 onlays, 4 inlays, and I crown made of Targis. In summer 1996, the six-month follow-up and in January 1997 the twelfe-month follow-up examinations were conducted. The results are very promising. A detailed report is being prepared.

5. 2. Targis Vectris crowns Head of study:. Dr. 1. Krejci, Dr 5.2. Targis Vectris crowns Head of study: Dr. 1. Krejci, Dr. Besek, Prof. F. Lutz Clinic for Preventive Medicine, Periodontology, and Cariology Centre for Operative Dentistry of the University of Zurich, Switzerland Subject: In this clinical study anterior and posterior teeth are restored with TargisNectris crowns. Patients have one to six teeth that require a crown. Experimental: Lab-fabricated crowns are seated on the prepared teeth (no linersibases are placed) with Syntac ("total etch technique") and an experimental luting composite (Vivadent). After 12 and 24 months, the restorations are examined. Abrasion (OCA/CFA), marginal quality and discolouration, sensitivity, surface texture and porosity, secondary caries, shade adaptation, shade stability, and condition of the gingiva are examined. Status: Thirteen crowns have been in place for one year. They were examined in the autumn of 1996. A detailed report is being prepared. Scientific Documentation Targis/Vectris Page 23 of 31

5. 3. Targis veneers Head of study:. Dr. R 5.3. Targis veneers Head of study: Dr. R. Welbury MB BS, BDS PhD FDSRCS Mr A. Shaw BDS, FDSRCS The Dental Hospital, Department of Child Dental Health Newcastle upon Tyne, Great Britain Subject: In this study, the following types of patients of the Child Dental Health Clinic are treated with veneers: - Patients with severely discoloured anterior teeth - Patients whose lost tooth structure cannot be restored withcomposites - Patients who do not wish to have orthodontic treatment Experimental: Once the patients have been registered for the study, their affected teeth are prepared. Subsequently, impressions are taken. During a second appointment, the lab-fabricated Targis veneers are seated using the adhesive technique. In the course of two years, a total of 200 restorations will be placed and evaluated in follow-up examinations. Status: By April 1997, 18 patients had received a total of 56 veneers.

5. 4. Vectris bridges: short-term study Head of study: Prof. K. H 5.4. Vectris bridges: short-term study Head of study: Prof. K.H. Kbrber, S. K,5rber, G. Johnke Clinic for Dental Prosthetics, University of Kiel, Germany Subj ect: Preliminary investigation of the clinical suitability of Vectris bridges Experimental: Thirteen patients were temporarily provided with 36 Vectris bridges (veneers of Chromasit/Spectrasit (Ivoclar). The wearing time up until the examination lasted an average 7.7 weeks. Results: The results were highly satisfactory. Consequently, additional investigations have been initiated. Status: This preliminary study has been concluded. Additional investigations have commenced in the following long-term study.

5. 5. Targis/Vectris bridges: long-term study Head of the study: Prof 5.5. Targis/Vectris bridges: long-term study Head of the study: Prof. K.H. K6rber, S. K6rber, G. Johnke Clinic for Dental Prosthetics, University of Kiel, Germany Subj ect: Examination of the clinical suitability and the period of undisturbed wear of TargisNectris bridges Experimental: A total of 32 patients are taking part in this clinical study. Of these patients, 17 patients required preprosthetic restorations, 12 required therapeutic vertical increase of occlusion, and three demonstrated an incompatibility to metal. A total of 66 bridges with different widths were incompati 1 avalable (There are nine anterior and 57 bridges in the premolar and molar region. Twenty-six of these bridges have two pontics and three have three pontics. The anterior bridges are divided into three bridges with one incisal and three with two incisals. One bridge has three Scientific Documentation Targis/Vectis Page 24 of 31 anteriors and two bridges four anteriors). In a follow-up examination, the restorations were evaluated according to clinical criteria: marginal periodontium, oral hygiene, status of the alveolar periodontium of the abutments, basic shape of the bridge, aesthetics, occlusion. The accuracy of the crown margin was deten-nined with an electrical probe. Status: By October 1996, the patients had been wearing the bridges for 14 months.

Results: Accuracy of the crown margin. Region. 0-100 pm "excellent" Results: Accuracy of the crown margin Region 0-100 pm "excellent" 100-200 Jim "Satisfactory" 200 pm- "unsatisfactory" [%] margin 65% 28% 7%

Patient response rates, in percentages, after 7 to 9 months of wearing Targis/Vectris bridges Questions excellent good average poor Handling of the bridge 86.3 10.6 3.0 0.0 Appearance 100.0 0.0 0.0 0.0 Chewing 24.2 74.2 1.5 0.0 Feel of bridge on tongue 92.4 4.5 1.5 0.0 Fit with teeth 96.9 3.0 0.0 0.0 Cleaning 1 84.8 15.5 1 0.0 0.0 none little average a lot Pressure after seating 92.4 6.0 1.5 0.0 Irritating taste 93.9 6.0 0.0 0.0 Chewing same as in the past 0.0 0.0 4.5 95.4 Good feeling about oneself 0.0 0.0 1 3.0 96.9

Discussion: The clinical investigators have come to the following conclusions based on this study: l The bridge method features negligible deficiencies in practical applications l The glass fibre structure allows a basic shape to be modelled, which is appropriate to tongue and masticatory movements l The fit of the crown margins corresponds to today's quality requirements l The material that comes in contact with gingival tissue does not cause reactions l Although accuracy of fit and occlusion were given priority during fabrication, no aesthetic defects were observed l The occlusion and masticatory functions can be effectively restored with VECTRISbridges. After a short period of wear, almost perfect results were achieved with only four local defects in the veneering material on 182 abutments or crowns (2.1 %). The light weight, fracture resistance, and the aesthetics of the bridges are impressive. Eighty-four percent of the patients were very satisfied with this type of restoration. Publication: Jonke et al., 1996; K6rber and K,5rber 1996

5. 6. Targis/Vectris bridges Head of study:. Prof. R 5.6. Targis/Vectris bridges Head of study: Prof. R. Slavicek University Clinic in Vienna, Austria Subject: Effects of cementation (conventional (Phosphacap) or adhesive luting (SyntacNariolink) on the clinical success of TargisNectris bridges. Experimental: Patients are provided with long-term temporary bridges. Ten bridges each are conventionally placed with a phosphate cement or with a composite cement using the adhesive technique. After a six-month wearing period, five bridges each are removed and examined extraorally. The remaining bridges are clinically evaluated over a period of two years. 20 TargisNectris Bridges 10 Conventi al cementation 10 Adhesive cementation 5 Removal after 6 months 5 Removal after 6 months 5 Follow-up examinations over 2 years 5 Follow-up examinations over 2 years Status: The study commenced in September 1996.

5.7. Targis/Vectris crowns: developmental investigation Head of study: Dr. B. Clunet-Coste Grenoble, France Experimental: Vectris crowns have been fabricated in combination with various resin materials (e.g. Chromasit/Spectrasit) and used in clinical situations since 1989. The glass fibres, the manufacturing process of Vectris, the lab techniques, as well as the veneering materials have all been consistently optimized. Although only developmental materials were available, the low rate of failure has been most impressive. Results: Year No. of crowns Failures Comments 1989 9 4 after I year 1990 12 3 1991/1992 21 0 1993/1994 173 1 1994/1995 1279 2 1 0 loss of retention Total 1494 10 0.7% errors

5.8. Targis/Vectris bridges: developmental investigation Head of study: Dr. B. Clunet-Coste Grenoble, France Experimental: Vectris crowns have been fabricated in combination with various resin materials (e.g. Chromasit/Spectrasit) and used in clinical situations since 1989. The glass fibres, the manufacturing process of Vectris, the lab techniques, as well as the veneering materials have all been consistently optimized. Although only developmental materials were available, the low rate of failure has been most impressive. Results: Year No. of bridges Failures Comments 1992 2 0 1993 2 0 1993/1994 15 1 1994/1995 149 3 1 loss of retention Total 168 4 2.4% errors A CRA clinical study on TargisNectris crowns (Dr. G. Christensen, Provo, Utah, USA) will begin in December 1996. Scientific Documentation Targis/Vectfis Page 27 of 3 1

6. Toxicological data 6.1. Introduction In the biological evaluation of medical devices, the chemical composition of materials, as well as the type and duration of their contact with the human body must be examined. The procedure required is described in ISO 10993 "Biological evaluation ofmedical devices" [1]. The suitable tests are deten-nined on the basis of this standard. In addition to the 10993 series, ISO/DIS 7405 [2] must also be used for the biological testing of dental materials. The release of soluble substances presents possible risks. According to ISO 10993 and ISO/ DIS 7405, the following biological effects should be examined in detail: cytotoxicity Sensitization Irritation Geiiotoxicity

6. 2. Toxicological evaluation for patients 6. 2. 1. Targis 6. 2. 1. 1 6.2. Toxicological evaluation for patients 6.2.1. Targis 6.2.1.1. Cytotoxicity Cytoxicity, the inhibition of cell proliferation, and other effects of the medical device on cells are determined with cell cultures. These tests provide an initial evaluation of the biocompatibility of the material. A direct cell contact test with Targis [3, 6] determined that this material does not demonstrate cytotoxic potential.

6.2.1.2. Sensitization and irritation These test results are used with suitable models to estimate the contact sensitizing potential of medical devices. In a maximization test on guinea pigs [4], Targis was demonstrated to be non-sensitizing. An irritant effect can also be ruled out on the basis of the test used.

6.2.1.3. Genotoxicity These tests are used to determine gene mutation, possible changes in the chromosome structure, or gene defects in cell cultures. The Ames Test is always used as the screening test. In this type of back mutation test [5], Targis Dentin and Incisal demonstrated no mutagenic changes.

6.2.2. Vectris Vectris is a fibre-reinforced, metal-free framework material for veneering purposes. The framework material is not in direct contact with living tissue in the mouth. It is first covered with Targis and then bonded to dentin with cement. The substances of the monomer matrix are well-known. They are comparable to those in Hellobond and Helioseal/Helioseal F. An adequate number of tests [7, 8, 9, 1 0], expert opinions [ 1 1 ], and clinical results are available for these materials. The glass fibres [12] are considered to be biologically inert. Direct exposure to the material in the event of the veneering material chipping off and related mechanical irritation can be practically excluded. Based on this information, individual testing of Vectn's according to ISO 10993-1 was consi 'dered to be unnecessary. Adequate data is available for the individual substances and comparable products. There is no indication that these materials are toxicologically han-nful on the basis ofthese results.

6. 3. Supplementary toxicological evaluation for dental technicians 6 6.3. Supplementary toxicological evaluation for dental technicians 6.3.1. All light-ctiring materials All light-curing materials in the TargisNectris-System contain dimethacrylate. Based on our literature and experiences, these products are non-irritant, even in an uncured state. The materials may cause irritation or an allergy or sensitization to dimethacrylates in hypersensitive people. This type of reaction can be avoided to a large extent if clean working conditions are assured and the uncured materials are not brought in contact with the skin. The working technique for these materials is state-of-the-art for dental technicians. Hence, working with these materials does not present a heightened risk. Information about the minimization of risks is contained in the Instructions for Use.

63.2. Vectris When working with glass fibre-reinforced materials, glass fibre dust may be produced. Special precautions must be observed, since fibre particles on the whole should not be inhaled. Even though the size of the dust particles produced during the finishing of Vectris frameworks is not within the international values given as presenting a high risk [12, 13, 14], the use of protective equipment (dust mask and vacuum extraction equipment, generally required when working with fine dust) is recommended in the Instructions for Use to minimize the risk of exposure.

Summary The toxicological risk of exposure to Targis/Vectris has been carefully examined to r both dental technicians and patients. The exposure of the dentist is not an issue in this connection.; On the basis of the available data and the latest findings, there is no indication thatTargisNectris present a hei htened or unacceptable risk if used according to the Instructions for Use Scientific Documentation Targis/Vectris Page 29 of 31

6. 4. Literature on toxicology [1] 6.4. Literature on toxicology [1] ISO 10993-1: Biologische WErkstoffprOfung von Medizinprodukten (1993) [2] ISO/DIS 7405: Preclinical evaluation of biocompatiblity of medical devices used in dentistry (1995) [3] In Vitro Cytotoxicity Test: Evaluation of materials for medical devices (Direct cell contact assay) CCR Project 534701 [4] Contact Hypersensitivity to C+B 90 Schneide + Dentin in Albino Guinea Pigs (MaximizationTest) RCC Project 608646

[5] Salmonella Typhimurium Reverse Mutation Assay with C+B 90 Schneide + Dentin (AmesTest) CCR Project 534702 [6] In Vitro Cytotoxicity Test: Evaluation of materials for medical devices (Direct cell contact assay) CCR Project 534800 [7] Primary eye irritation study with Helloseal in Rabbits RCC Project 034604 [81 Salmonella Typhimurium Reverse Mutation Assay with Helioseal F (Ames-Test) CCR Project 427206 [9] Contact Hypersensitivity to Helioseal F in Albino Guinea Pigs RCC Project 347095

[10] Cytotoxicity Test in Vitro: Agar Diffusion Test with Helloseal F CCR Project 409904 [I 1] Toxlkologisches Sachverstdndigen-Gutachten fiber Helloseal nach AMG _ 24, Abs. 1, Nr. 2 [12] Est-11 dangereux de manipuler la fibre de verre?, Dr. Esquevin, M6decin du Travail [13] DFG: @- und BAT-Werte-Liste, 1996 [14] Gutachterliche Stellungnahme betreffend das gesundheiliche, Inhalative Risiko beim Verarbeiten vom GerilstwerkstoffVectris der Firma Ivoclar RCC Projekt 620280 Scientific Docmentation Targis/Vectris Page 30 of 31

7. Literature Janda R Kleben und Klebetechniken 7. Literature Janda R Kleben und Klebetechniken. Teil 1: Aligemeine Prinzipien der Klebetechnik Dent Labor 40, (1992) 409-415 Janda R Kleben tind Klebetechniken, Teil 2: Adhdsiv-Systemefiir Zahntechnik und Zahnmedizin Dental Labor 40 (1992) 615-628 Krejci I, Reich T, Lutz F, Albertoni M In-vitro-Testverfahren zitr Evahiation dentaler Restaurationssysteme 1. Computer-gesteuerter Katisimitlator Schweiz Monatsschr Zahnmed 100 (I 990) 953-960

Schwarz S, Lenz J, Melers H Zur Anwendting des Dreipiinkt-Biegetests beim Metall IKunststoff-Verbund Dtsch Zahn5rztl. Z 47 (1992) 299-302 Schwickerath H Zur Verbundfestigkeit von Metallkeramik Dtsch Zahndrztl. Z 35 (1989) 910-912 Tiller H-J, Magnus B, G6bel R, Musil R Der Sandstrahlprozess und seine Einwirkung aufden Oberfa-chenzustand von Dentallegierungen (I) Quintessenz 10, (1985) 1927-1934 Tiller H-J, G6bel R, Magnus B, Musil R Der Sandstrahlprozess und seine Einwirkung aufden Oberfdchenzustand von Dentallegierungen (II) Quintessenz 10, (1985) 2151-2158

Publications for Targis/Vectris: Bischoff H E,ste Erfahrungen mit metallfreien Ceromer-Briicken Dent Labor 44, (1996) 1807-1815 Bourrelly G Compreiidre les composites de laboratoire Proth Dent 121, (1996) 29-31 Cadiou D, Grundler T Le concept Targis/Vectris, 2eme partie Proth Dent 124, (1997) 27-31 Clunet-Coste B Targis/Vectris Proth Dent 124, (1997) 33-37 Johnke G, K6rber K-H, K6rber S Die Glasfuserverstirkte Briicke ZM 86, (1996) 38-43

Korber KH, Korber S, Ludwig K Metallfrei Briieken fur die restaurative Zahnheilkunde Dent Labor 45, (1997) 465-476 Korber KH, Korber S, Ludwig K Experimentelle Untersuchungen liber den Versteiftingseffekt von faserverstfirkten Briiekengeriisten Vectris nach Vollverblendting mit Ceromer Targis Quintessenz Zahntech 11, (1996) 1343-1354 Korber KH, Kbrber S Mechanische Festigkeit von Faserverbund-Briicken Targis-Vectris ZWR 105, (1996) 693-702 Korber S, Korber KH Glasfaser-Briicken-Zahnersatz Zahnarzt Magazin 3, (1996) 32-42 Touati B The evolution of aesthetic restorative materials for inlays and onlays: a review The Int Aesth Chron 8, (1996) 657-666