Proficience Ceramco Ic

Clinical and Scientific Perspectives on an Integrated Ceramic System (Ceramco iC)

Christopher C. Y. Chu, Nels O. Ewoldsen, Christopher R. Kennedy and Veeraraghavan Sundar Clinical cases courtesy of Michael A. Miyasaki, Todd C. Snyder, Joao Moraes, Juliano Vasconcellos, Jurgen Gebhardt, Catherine Catanzaro, Michael DiPaulo, Nelson Ochoa and Nels O. Ewoldsen. Abstract: Dental restorations have been targeted at re-establishing function and recreating esthetics from their earliest days. These same targets serve today as goals used to refine dental ceramics. The evolving design and applications of these ceramics result from continuing collaboration between dentists, technicians, and materials scientists, aimed at better clinical performance for patients. The development of Ceramco iC, a unique integrated ceramic system offers a single set of materials to fabricate all these restorations. The immediate advantages are enhanced reproducibility, excellent esthetics, a full spectrum of shades for prescription, as well as reliable shade match in combination cases involving more than one type of restoration.

Clinical and Scientific Perspectives Ceramco iC

DENTSPLY Prosthetics

Introduction: Dental restorations have been targeted at re-establishing function and recreating esthetics from their earliest days. These same targets serve today as goals used to refine dental ceramics. The evolving design and applications of these ceramics result from continuing collaboration between dentists, technicians, and materials scientists, aimed at better clinical performance for patientsi. Multiple methods of fabricating dental restorations offer todays practitioner an expanded palette of esthetic choices, backed by reliable processing methods. Some of these methods with a brief description and advantages are outlined in Table 1. Table 1: Types of Dental Restorations

Restoration Type How is it Created Advantages

Porcelain-Fused-to-Metal (PFM)

Building up or stacking porcelain on a cast metal substructure

Broadest range of indications; clinical gold standard for over half a

century.

Press-to-Metal (PTM) Pressing an ingot of dental ceramic onto a

cast metal substructure

PFM Indications, plus reproducible esthetics, and

precise contours and margins

All-Ceramic (AC)

Pressing an ingot of dental ceramic into a mould, with the ceramic itself (or a high

strength ceramic) serving as the substructure.

Unparalleled esthetics and translucency in single unit

applications.

The development of Ceramco iC, a unique integrated ceramic system offers a single set of materials to fabricate all these restorations (Fig. 1). The immediate advantages are enhanced reproducibility, excellent esthetics, a full spectrum of shades for prescription, as well as reliable shade match in combination cases involving more than one type of restoration (Table 2). In this brochure, we present the Ceramco iC system, its advantages, and treat some clinical aspects of the system. Fig. 1: Esthetics of Ceramco iC restorations (Courtesy Juergen Gebhardt, MDT)

Restored with Ceramco iC Incisal Translucency

Ceramco iC: Enhanced Esthetics The Ceramco iC system was designed to be highly esthetic. Shades corresponding to both the Vita Lumin and the VitaPan 3D-Master guides are available. The colors and graded opacities of the components of the integrated system, such as the opaque, opaceous dentin and dentin layers of the porcelain, as well as ingots, are maintained within controlled ranges using advanced spectrophotometric techniques. This



control aids in reproducible esthetics across a wide variety of clinical situations (e.g. combination cases), and less technique sensitivity. The development of phase-separating opal enamels, natural enamels, chroma-rich modifiers and super-clear enamels have enhanced the esthetic possibilities of the system (Fig. 2). Table 2: Integrated Components of the Ceramco iC System

Restoration Type PFM Press to Metal All-Ceramic

Stains/Glazes

Enamels/Mamelons

Dentins/Modifiers

- Ingots

Opaques -

Alloys -

N/A Stump Shades

Restoration Type PFM Press to Metal All-Ceramic

Fig. 2: Highly esthetic Ceramco iC restorations (Courtesy Juergen Gebhardt, MDT)

Before Ceramco iC -Maxillary

Ceramco iC Mandibular Restored Smile

Ceramco iC: The Benefits of Engineered Microstructure Leucite is a crystalline ceramic (KAlSi2O6) used primarily to modify thermal expansion properties of glasses to match alloys routinely used in dentistryii. Leucite containing glass-ceramics (porcelains) have been in routine use in PFM restorations for over fifty years. Conventional PFM porcelains can be routinely fired at temperatures higher than 900C. They contain high (35-55%) levels of leuciteiii.



However, high levels of leucite with large crystal sizes have been associated with some undesirable effects, such as an increased tendency to wear opposing dentitioniv. Ceramco iC materials contain a uniform and fine-grained leucite structure (Fig. 3). Fig. 3: The uniform, engineered microstructure of Ceramco iC

Conventional Porcelain Ceramco iC engineered microstructure

The advantages of better engineered leucite levels and microstructures in state of the art dental ceramic systems such as Ceramco iC, as observed by in-vitro studies and clinical observation are lowered wear to opposing dentition and enhanced polishabilityv. In addition, modern engineered microstructures are also associated with lower fusion temperatures for dental ceramics. This ensures that thermal mismatch stresses, developed as the porcelain cools from its glass transition temperature to room temperature, are minimized. A microstructural examination of the veneering porcelain interfaces with ingots and opaques over metal reveals superior adhesion (Fig. 4). Fig. 4: Engineered Interface Microstructures Ceramco iC enhance bonding

Porcelain-Ingot Interface Porcelain-Opaque-Metal Interface

Ceramco iC: Technical Profile A review of the technical properties of the PFM, PTM and AC components of the Ceramco iC system demonstrates that they meet and exceed appropriate international standards. Table 3: Technical Profile of Ceramco iC Components

PFM PTM AC

Applicable International Standards: ISO 6872, 9693

Flexural Strength: 90 MPa

CTE: 12.0 /m/K

Bond Strength to Alloy: 51MPa


CTE: 13.0 /m/K

Bond Strength to Alloy: 53MPa


CTE: 13.0 /m/K

Chemical Solubility:

33.1 g/cm2



PFM PTM AC


15.1 g/cm2


33.1 g/cm2

Other properties

Processing temp: 840C

Leucite Size: 1-5

Pressing Temp: 890C

Leucite Size: 1-5

Pressing Temp: 890C

Leucite Size: 1-5

Preparation

Conventional PFM:

Shoulder/Chamfer Margin with 0.8-2mm reduction and rounded line angles

Conventional PFM:

Shoulder/ Chamfer Margin with 0.8-2mm reduction and rounded line angles

Conventional All Ceramic: Shoulder/Deep Chamfer Margin with 1.5-2mm reduction and rounded line angles

Shade Check Shade Guide Shade Guide Shade Guide with

DENTSPLY All-Ceramic Die Material

Placement

Conventional Cementation (SmartCem2) or Adhesive Bonding (Calibra)

Conventional Cementation (SmartCem2) or Adhesive Bonding (Calibra)

Adhesive Bonding (Calibra)

In addition, the engineered leucite microstructure for Ceramco iC components detailed in the previous section results in lower wear to opposing enamel, compared to conventional porcelains (Fig. 5). Taken together, these in vitro results are predictors of clinical excellence. Fig. 5: Lower Wear of Opposing Dentition of Ceramco iC compared to Conventional Systems

Data on File, test conducted at Creighton University, Dr. Mark Latta PI

Ceramco iC All-Ceramic: An Esthetic Evolution Over ten years of experience has resulted in the development of the Ceramco iC all-ceramic components. This class of materials uses surface or bulk nucleation mechanisms to create and grow leucite crystals (25-45 wt%) in a feldspathic glass matrixvi. This leucite acts not only as a thermal expansion modifier, but also as a dispersion strengthening phase (Fig. 4).

The pressing procedure in which ingots of these materials are injection molded into a lost-wax cavity under medium pressure reduces the porosity and flaws common in hand-built porcelain veneering layers. Consequently, these materials are significantly stronger (135MPa, 3-point bend flexural strength, Table 3) compared to dental porcelains (



advantages of high transparency, and can be shaded in a manner similar to dental porcelains, by the addition of inorganic oxide pigments. An esthetic advantage the all-ceramic materials have offered, since their commercialization, is the possibility of eliminating the metal substructure for single units. The two phase structure (leucite and glass) makes it possible to acid-etch and silanate the interior surface of the crown. Using resin cements and dentin bonding agents, a very strong and retentive bond is created with the prepared toothviii. The increased initial strength and the effects of adhesive bonding of all-ceramic restorations using resin cements have ensured that this class of materials has a high clinical success rate when used for single unit restorations in the anterior region: 95-98%, in 5-11 year rangesix,x. The lower success rate (85%, 11 years) in the posterior has led to a contraindication for use behind the second bicuspidxi,xii. In the following sections, we will examine clinical case reports that demonstrate the esthetic possibilities of this system.

Advantage: iC The Ceramco iC system improves upon previous generations of materials. Some of these advantages are listed here.

Expanded range of indications for PFM, PTM and AC cases

Forty six shades in a single system (including shades corresponding to A-D, 3-D Master and bleached)

All components of the iC system are inter-compatible, without any time-consuming adjustments or mixtures.

Additionally, veneering with low-wear iC porcelain ensures significantly reduced wear against opposing natural dentition.

It is possible to press a coping of this material and veneer it in a manner similar to a PFM coping. This is currently not feasible with many other all-ceramic systems. Familiar incisal cutback and surface staining may also be employed to color the core materialsxiii.

Clinical esthetics are improved by using a resin composite die material to simulate the shade of the prepared tooth while comparing the shade of the restoration.

Fig 6: Patient at presentation

Patchwork of Composite Restorations Conservative Preparations

Clinical Case Report 1 All Ceramic Crowns - Courtesy Dr. Nels Ewoldsen, DDS, MSD The following clinical case report illustrates the ease of use of the Ceramco iC system for esthetic, bonded all ceramic restorations. The patient presented with both esthetic deficiencies a patchwork of prior composite restorations, and functional issues non-optimal OVD due to a collapsed bite from



anterior wear (Fig. 6). A diagnostic wax-up was used to present treatment options to the patient. After informed consent was obtained, conservative chamfer preparations were created to receive bonded all-ceramic iC restorations (Fig. 6). Subsequently, the patient was provisionalized using the Radica VLC system. Bonded Radica mandibular provisionals were used to establish and test a new occlusal vertical dimension, OVD (Fig 7). Fig 7: Radica Provisionalization

Radica Provisionals Mandibular Radica OVD Build-Up

Teeth #6-#10 were now considered ready to receive all-ceramic restorations. These restorations were created using pressed value series ingots, followed by staining in the D2 shade. The resulting restorations showed a high level of esthetics. Minimal adjustment was required, being limited to contact adjustment with a diamond strip. The preparations received Prime & Bond NT dual cure bonding agent and silane treated restorations were bonded using Calibra esthetic resin cement (Fig. 8). Fig 8: Ceramco iC restorations

Bonded Restorations Restored Smile

The patient expressed a high level of esthetic satisfaction with the results, especially in comparison with the situation as presented (Fig. 9).

Clinical Case Report 2 Laminate Veneers - Courtesy Dr. Joao Moraes, T. P. D. Juliano Vasconcellos

The following clinical case report illustrates the ease of use of the Ceramco iC system for esthetic, bonded ceramic laminate veneers. The patient, a 45 year old man, presented with tetracycline staining, diastemata, and Class II malocclusion. The patient presented after an years orthodontic treatment in the mandibular. He required maxillary reconstruction and smile lifting with a view to an improved functional and esthetic situation post treatment. Better vertical to horizontal dimension ratios in the crowns would enhance anterior esthetics. It was decided to enhance the esthetics of 8 anterior maxillary units with refractory veneers. This course of treatment was selected due to its conservative (minimally invasive) nature but excellent esthetic potential.



Fig 9: Ceramco iC All Ceramic - Before and After Images

Before After

A diagnostic wax-up was created to aid in treatment planning and illustrate expected outcomes (Fig. 10). A try-in of the diagnostic wax-up confirmed both the patients and the treatment teams esthetic and functional expectations. Fig 10: Situation at Presentation

Before Diagnostic Wax-Up

Fig 11: Preparation and Provisionalization

Preparation Provisionalization



Relatively conservative veneer preparations were created to ensure esthetic outcomes, keeping in mind the fact that under-preparation often militates against esthetics, especially with laminates. Modified chamfer margins were used to enable clear designation of margins by the technical team. Provisionalization was accomplished following the diagnostic wax-up guidance (Fig. 11) using a bis-acryl resin (Luxatemp, DMG) and a VPS putty template (Zetalabor, Zhermack SpA). As part of the laboratory procedure, a wash firing using Ceramco iC opaceous dentin (Shade A2) was initiated to mask the underlying staining. A mixture of A2 opaceous dentin and HC4 high chroma modifier was added at the next firing to imbue depth of color in the cervical areas. In the next firings, a mix of B3 and A2 dentin was used. Enamel shades Violet, Extra Light, Super Clear and Opal Enamel Clear were subsequently fired on to add depth of translucency, followed by a glaze firing. The result was a vital and natural looking set of laminate veneers (Fig. 12). The veneers were tried in for position and contour. Only minor modifications (using water cooled diamond tools) were necessary. The ceramic veneers with etched with 5% hydrofluoric acid, and subsequently silanated in preparation for placement. A self adhesive resin cement system (RelyX ARC, Shade A2, 3M ESPE) was used to bond the veneers in place. A harmonious and natural smile resulted. The treatment sequence was completed efficiently in a 5-day span. The patient was very satisfied with the natural smile resulting, as were we. Fig 12: Laboratory Steps

Laminate Veneers Initial Firings Venee Restorations

Fig 13: Final Restorations

Retracted Natural Smile

Clinical Case Report 3 Ceramic Inlay Courtesy Dr. Todd C. Snyder The following clinical case report illustrates the ease of use of the Ceramco iC system for esthetic, bonded all-ceramic inlay.



Fig. 14: Situation at Presentation and Preparation

Resin Restoration on #13 Initial cavity preparation with caries indicator

The patient, a forty four year old female, presented with a chief complaint of an old restoration with sensitivity on tooth # 13. Her medical history was unremarkable and there were no contraindications to dental treatment. Tooth #13 had been restored with a composite resin restoration. The restoration had signs of wear, marginal breakdown and the tooth itself had a crack on the distal margin (Fig. 14). The adjacent amalgam is to be replaced at a subsequent visit. Treatment options were discussed with the patient and it was decided to replace the existing restoration with a durable esthetic all ceramic restoration (Ceramco IC, Dentsply Prosthetics) that would not compromise the existing appearance of the tooth. The existing restoration was removed and the conservative preparation was created. Due to the depth of the existing restoration and recurrent decay a caries indicator was used (Fig. 14). Upon removing the recurrent decay a glass ionomer base was placed to protect the pulpal floor (Fig. 15). The crack on the mesial was determined to be too small to necessitate treatment as the amount of tooth structure that would have to be removed to place an indirect material would reduce too much tooth structure thus compromising the integrity of the tooth more than adhering the tooth together with a bonded inlay. Fig. 15: Preparation Details and Impression

GI Base with Prep Design VPS Impression

The ideal depth was created with the base being reduced slightly, along with the axial walls diverging 6-10, to allow for proper line of draw without compromising the existing tooth structure. Figure 12 shows the initial clean out of the composite restoration, along with some interproximal bleeding from inflammation, as well as the caries indicator. Figure 15 shows the glass ionomer base placed along with ideal preparation design, as well as the VPS impressions of the case illustrating the conservative preparation requirements. The provisional restoration was fabricated out of bis-acryl provisional material (Fig. 16).



Fig. 16: Provisional and Restoration on model

Bis-Acryl Provisional Restoration on Model

The Ceramco iC restoration material was chosen for the inlay based on the fact that it is a durable conservative esthetic system. The translucency of the all-ceramic ingots and the dentin and enamel components of the veneering porcelain provide for an extended range of shade matching possibilities. The system also provides for laboratory efficiencies. The restoration on a model is shown below, as well as in the try-in phase to verify contours (Fig. 16). The All Ceramic restoration was placed with a dual cure resin cement and a self-etched adhesive bonding agent. The completed case is shown below (Fig. 17). We were able to restore the overall strength of the tooth while keeping the same esthetic appearance of the tooth, and conservatively augment the tooth without compromising gingival health or destroying additional tooth structure. The patient was very pleased with the results. The marginal adaptation and excellent soft tissue response achieved with the system chosen enabled the satisfactory completion of the case. Fig. 17: Completed Case

Completed Case Close-Up of Completed Case

Clinical Case Report 4 Multiunit Maxillary Restoration Courtesy Dr. Michael A. Miyasaki The following clinical case report illustrates esthetic results of the Ceramco iC system for a multiple unit reconstruction. The patient, a forty-nine year old female, presented with a chief complaint of not liking her smile, because the color, length and chipping of the teeth. She wanted a beautiful smile. Her medical history is currently unremarkable, but she did have a history of acid reflux which is now controlled and there were no other contraindications to dental treatment. Fig. 18 is an illustration of the anterior teeth showing the wear, discoloration and the lingual acid erosion. It was apparent that any restorations we placed should protect the teeth and be conservative in nature due to the extent of the lingual erosion.



At our first consultation the patient was unsure if the teeth should be any longer in length and whiter as we recommended so we offered to place acrylic over the unprepared teeth, in order to allow her to preview her new smile. We made a diagnostic wax-up and over this made a VPS putty stent (Figure 19, Aquasil Ultra, DENTSPLY Caulk, Milford DE). Fig. 18 Preoperative Situation

Pre-Operative Smile Lingual Erosion

Fig 19- Treatment Planning

The Wax-Up Putty Stent Fabricated Over The Wax-Up

When the patient returned we filled the stent with a bis-acryl temporary material (Integrity Temporary C&B Material, Dentsply Caulk, Milford, DE) and placed the stent over the teeth, again unprepared (figure 19), and the patient was allowed to wear this for a week. When the overlay was first placed the patient commented that the teeth looked too long and too white, but I reassured the patient that changes could be made before the final restorations were fabricated. A week later the patient asked if the teeth should be longer and whiter. Fig. 19: Acrylic Overlay and Preparation Guide

Patient with the acrylic overlay Half of arch prepared and showing tooth #4 with implant supported crown



At this point the patient was very anxious to begin treatment and we discussed the various treatment options from direct composite restorations, PFM crowns, and minimally invasive all porcelain crowns and onlays and it was the last that was selected. Dentsply Prosthetics Ceramco iC was selected for the ten esthetic all ceramic restorations consisting of crowns and onlays on teeth #4-13. The Ceramco iC restoration material was chosen for the inlay based on the fact that it is a durable conservative esthetic system. The translucency of the all-ceramic ingots and the dentin and enamel components of the veneering porcelain provide for an extended range of shade matching possibilities. Figure 19 also demonstrates one side of the arch prepared and the other side of the arch still covered with acrylic so we could visualize the position of the final restorations and minimize tooth structure removed during preparation. Figure 20 shows the full arch prepared and the areas of the gingival that were lasered. The multiple restorations were impressed with the VPS (Aquasil Ultra, Dentsply Caulk). Nicely defined margins were captured on the first try (Fig. 20). Fig. 20: Preparation and Impression

Conservative Preparations Multiple Tooth Impression with Aquasil VPS

Fig. 21 illustrates the well fitting lab fabricated restorations. The interproximal contacts have been perfected on the models to ensure easy delivery of the restorations. Fig. 21: Restorations on the Model

Anterior View of Restorations Occlusal View of Restorations

During cementation care to prevent contamination of the preparations during cementation as well any interproximal adjustments makes the rubber dam placement (Figure 22) of utmost importance. Having the rubber dam prevents the lips and tongues from causing contamination or dislodgement of the restorations and allows for placement of the ten restorations simultaneously during cementation. These all Ceramic restorations were placed with an esthetic resin cement and a dual cure bonding agent (Calibra with Prime and Bond NT, Dentsply Caulk, Milford DE). The patient was thrilled with the final result that made the teeth smoother, whiter and longer giving her the smile she had wanted for decades (Figure 22).



Fig. 22: Cementation and Final Results

Cementation with use of rubber dam for control and proper isolation

Patient was thrilled with completed case

Summary The Ceramco iC system offers an excellent esthetic alternative to clinical practitioners interested in metal-free restorative systems. It is in line with the current development of several esthetic dental restorative alternatives, and can offer clinical practitioners, dental laboratories, and patients enhanced intraoral function, along with enhanced esthetics. Supplementary Armamentarium Recommendations

Custom Trays: Triad VLC custom trays (DENTSPLY Trubyte)

Diagnostic Restoration: Radica Provisional/Diagnostic System (DENTSPLY Ceramco)

Impression Material: Aquasil Ultra VPS (DENTSPLY Caulk), Genie VPS (Sultan HC)

Anesthetic: DENTSPLY Benzocaine Oral Anesthetic Gel, 2% Xylocaine DENTAL with epinephrine, 1:50,000 , 3% Polocaine for longer procedures (DENTSPLY Professional)

Prep Kit: Midwest Carbide 2158 Carbide, Midwest Diamonds: KS0 Cylinder, KS3 Cylinder, KS5 Teardrop, 878K Taper Modified Bevel, 858 Needle, 392 UltraNeedle Interproximal. Alternatively: Depth Cutter #834 (471443), Cylinder Flat #837 (471092), Tissue Protective, end-cutting Cylinder Bevel #899 (10839), and Taper Round #856 (471210) form a heavy chamfer prep kit. (DENTSPLY Professional)

Cords: Ultrapak (Ultradent), SulPak, Ultrax (Sultan HC)

Desensitization: Calm-it densitizer (DENTSPLY Caulk)

Provisional Restoration: Lab- Radica Provisional/ Diagnostic System (DENTSPLY Ceramco), Chairside- Integrity Temporary C&B (DENTSPLY Caulk), or VersaTemp (Sultan HC)



Provisional Cementation: Integrity Temp-Grip (DENTSPLY Caulk), or SensiTemp NEZO (Sultan HC)

Conventional Cementation: SmartCem 2 (DENTSPLY Caulk)

Adhesive Bonding: Prime and Bond NT unit dose, Calibra Esthetic LC resin cement

Curing Light: SmartLite PS (DENTSPLY Caulk)

Polishing: Dialite System (Brasseler USA)

Endodontic Treatment Access: Midwest KS3 diamond bur, Ultracoarse 2801 round diamond bur (DENTSPLY Professional)

REFERENCES i Kelly JR, 1997, Ceramics in Restorative and Prosthetic Dentistry, Ann. Rev. Mater. Sci.,, v27, p443-68. ii Gonzaga CC, Okada CY, Santos AL, Goulart EP, Sundar V, Cesar PF, Miranda WG Jr, and Yoshimura HN, 2002, Microstructure of Dental Porcelains, J. Dent. Res., v81(4), No. 1857. iiiPiche PW, O'Brien WJ, Groh CL, Boenke KM, 1994,Leucite content of selected dental porcelains, J Biomed Mater Res. , May;28(5):603-9 iv Imai Y, Suzuki S, Fukushima S., 2000, Enamel wear of modified porcelains, Am J Dent., Dec;13(6):315-23. v Wright MD, Driscoll CF, Romberg E, Thompson GA, 2002, Comparison of three porcelain polishing kits for ultra-low fusing dental porcelain, J. Dent. Res., v81(4), No. 3832. vi Beham G, 1990, IPS Empress: A New Ceramic Technology, Ivoclar-Vivadent Report 6, 3, Ivoclar AG, Schaan, Frstentum Liechtenstein. vii Gorman CM, McDevitt WE, Hill RG., 2000, Comparison of two heat-pressed all-ceramic dental materials, Dent Mater., Nov;16(6):389-95. viii Sheykholeslam Z, Buonocore MG, 1972, Bonding of resins to phosphoric acid-etched enamel surfaces of permanent and deciduous teeth, J Dent Res., Nov-Dec;51(6):1572-6. ix Probster L, Geis-Gerstorfer J, Kirchner E, Kanjantra P., 1997, In vitro evaluation of a glass-ceramic restorative material., J Oral Rehabil., Sep;24(9):636-45. x Barnes D, Gingell JC, George D, Adachi E, Jefferies S, Sundar V., Clinical evaluation of an all-ceramic restorative system: 24-month report, Am J Dent. 2006 Aug;19(4):206-10. xi Fradeani M, Redemagni M, 2002, An 11-year clinical evaluation of leucite-reinforced glass-ceramic crowns: a retrospective study, Quintessence Int., Jul-Aug;33(7):503-10. xii Malament KA, Socransky SS, Thompson V, Rekow D., 2003, Survival of glass-ceramic materials and involved clinical risk: variables affecting long-term survival, Pract Proced Aesthet Dent., Suppl:5-11. xiii Berland LF, 1999, Building a better cosmetic practice, Dent Today, Jun;18(6):56-8, 60-1.

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