Ceramic prosthetics can provide patients with durable, functional and esthetic restorations. While all phases related to this process are important, this article will focus on the proper delivery of a ceramic restoration. Proper delivery will mean utilization of the right materials and the proper technique. Among the materials necessary is a dentin-enamel bonding system, a ceramic primer and a luting resin. There are varying opinions as to the treatment of the ceramic itself. Considerations in the treatment of porcelain surfaces include surface roughening of the porcelain, the use of hydrofluoric acid and the use of silane.
Surface roughening
It has shown that surface roughening will improve bond strengths to porcelain. The roughening may be accomplished via air-driven particulates (i. e. sandblasting) or by the use of hydrofluoric acid. The use of sandblasting alone has been shown to improve bond strengths to porcelain, although it is most frequently used in conjunction with hydrofluoric acid. 1-3 Ironically, while surface roughening improves bond strength of resin to porcelain, roughening, including sandblasting, has also been shown to decrease the fleural strength of porcelain. 4-8 The use of a resin following defect introduction is shown to improve flexural strengths. 9-10
Hydrofluoric acid
Horn11 first suggested the use of ceramic etching to aid retention and it was further explored by Simonsen and Calamia. 12 They used 7.5% hydrofluoric acid to create a micro-porous porcelain surface to aid retention. Later, Stangel, Nathanson and Hsu used both 20% and 52% hydrofluoric acid to etch porcelain. 13 Currently there is no one recommended approach to porcelain treatment, although some are similar to one another. Chen at al reported that the use of 5% HF for 120 seconds yielded the highest bond strengths. 14 Gler et al suggested 9.6% for 120 seconds. 15 Nagayassu et al recommended 10% HF for 120 seconds. 16 Boscato, Della Bona and Del Bel Curry found 9.5% HF for 120 to yield the highest bond strengths, 17 while Peumans et al found 4.9% HF for 60 seconds to be effective. 18
Silane
Silane has long been recommended for the treatment of porcelain surfaces.19-21 Although there is sometimes a debate as to its necessity, many researchers feel that not only is it important, it is the most important element in porcelain bonding. 14,22,23 Barghi asserted that silane provides a bond more reliable than with HF alone. 24 Silane also is reported to improve the long term stability of resin bond to porcelain. 25
A ceramic onlay is treatment planned for the mandibular first molar seen in Figure 1. A facial view shows staining under an old resin composite restoration (Fig. 2). The preparation for the onlay is seen in Figure 3. A temporary onlay is formed (Fig. 4) and the preparation is sealed with a no-rinse dentin-enamel resin adhesive (Surpass®, Apex Dental Materials, Sure Dental Innovations, Oakville, Ontario, CA). Surpass® is a three bottle self-etching bonding system capable of affixing any type of resin composite — light-cure, dual-cure and self-cure resin composites. It can be made exquisitely thin and can be utilized for both direct and indirect procedures. Surpass TM has been tested at Tufts, the University of North Carolina and at an independent, non-profit dental education and product testing foundation, generating over 50 MPa of bond strength at each venue within two hours (notched shear test method). As it has a separate conditioner, primer and bonding resin, it is similar to 4th generation systems. It performs as well as any 4th generation system yet is easier to use.
Delivery of a ceramic restoration can be described as having three components; treatment of the tooth, treatment of the prosthesis, and the cement to join the two.
The Tooth
In the present case, the preparation sealed with the resin adhesive on the day it was prepared. Surpass® 1 was applied to dentin and enamel for 10 seconds and left wet. Three brushfuls of Surpass® 2 were applied directly to the wet prep and then dried very thoroughly for ten seconds. A thin layer of Surpass® 3 was applied to the prep and dried to a very thin layer. Each surface was light-activated for tens seconds. The temporary was inserted with a non-eugenol temporary cement (Fig. 5).
On the day of delivery, the temporary is removed, the prep is cleaned of the temporary cement, and the onlay in tried in for fit. Removal of the temporary cement fragments may be facilitated with the use of Consepsis Scrub™ (Ultradent, Sandy, UT) on a small brush or even on a cotton pellet. Particle abrasion is discouraged as it may induce bleeding from the surrounding soft tissues.
The Restoration
To ready the onlay for insertion, the inner surface of the onlay is carefully inspected for defects and is carefully cleaned with either steam or an acetone wash and dried. The inner surface of the onlay will be treated with Interface (Sure Dental Innovations). Interface™ is a combination silane and ceramic conditioner. The use of hydrofluoric acid is not necessary with Interface. In addition, Interface can be used to treat porcelain prostheses being inserted and can be used for ceramic repairs. Interface is highly rated by an independent, non-profit dental education and testing foundation. In an investigation including three different types of porcelain — VMK II Cerec Blocks (Vident, Brea, CA), Procad, the CAD/CAM version of Empress (Ivoclar Vivadent, Amherst, NY), and Ceramco 2 (Dentsply Ceramco, York, PA) — Interface and Simplicity® 2 were shown to perform as well as the control HF etching and a one bottle adhesive. 26
A drop of Interface A and Interface B are mixed together in a well. After approximately 30 seconds the silane conditioner/primer is ready for application. The mixture is applied to the inner surface of the ceramic onlay and it is dried thoroughly. A coat of Surpass® 3 is then applied to the internal surface, blown with compressed air to a very thin layer and light-cured for ten seconds.
Surpass® 3 is then re-applied to the preparation and light-cured once more (Fig. 6).
The Cement
The luting resin composite of choice is Anchor® (Sure Dental Innovations). Anchor® is a dual-cure resin composite that serves as a core build-up material, post luting resin cement and a ceramic crown and onlay cement. The resin cement is dispensed from the auto-mix cartridge into the prosthesis (Fig. 7) and the onlay is seated (Fig. 8). A dual-cure resin cement, Anchor® offers a prolonged gel phase prior to hardening. This provides a comfortable period of time during which the excess cement may be easily removed from the margins. Then floss is run downward and outward through the proximal spaces. The complete onlya is then light-activated for 10 seconds per surface. The occlusion is adjusted as necessary and the porcelain is polished (Fig. 9). The completed restoration is shown in Figures 10 and 11. The recall image is seen in Figure 12.
This article has illustrated a predictable method of delivering a ceramic onlay using dependable materials. Success can be obtained on a regular basis if proper and effective protocols are utilized and kept fairly simple. While the present article depicts the insertion of a ceramic onlay, the principles remain the same for other types of ceramic restorations as well.
More information can be obtained at suredental.comand at apexdentalmaterials.com. Video instructions are availa
ble for each of the products mentioned above. oh
Dr. Kanca is a lecturer, author, researcher and inventor. He has lectured all over the world and maintains a private practice in Middlebury CT. He is known for discovering wet bonding and making dentin etching viable and is a leading authority on bonding.
Oral Health Welcomes This Original Article.
References
1. Roulet JF, Sderholm KJ, Longmate J. Effects of treatment and storage conditions on ceramic/composite bond strength. J Dent Res. 1995 Jan;74(1):381-7.
2. Chung K, Hwang Y Bonding strengths of porcelain repair systems with various surface treatments. J Prosthet Dent. 1997 Sep;78(3):267-74.
3. Wolf D, Powers J, O’Keefe K. Bond strength of composite to etched and sandblasted porcelain. Am J Dent. 1993 Jun;6(3): 155-8
4.de Jager N, Feilzer AJ, Davidson CL. The influence of surface roughness on porcelain strength. Dent Mater. 2000 Nov;16(6):381-8.
5. Fleming GJ, El-Lakwah SF, Harris JJ, Marquis PM. Dent Mater. 2004 Feb;20(2):142-9. The influence of interfacial surface roughness on bilayered ceramic specimen performance. Dent Mater. 2004 Feb;20(2):142-9.
6. Albakry M, Guazzato M, Swain MV. Effect of sandblasting, grinding, polishing and glazing on the flexural strength of two pressable all-ceramic dental materials. J Dent. 2004 Feb;32(2): 91-9
7. Addison O, Marquis PM, Fleming GJ. The impact of hydrofluoric acid surface treatments on the performance of a porcelain laminate restorative material. Dent Mater. 2007 Apr;23(4):461-8.
8. Addison O, Marquis PM, Fleming GJ. The impact of modifying alumina air abrasion parameters on the fracture strength of a porcelain laminate restorative material. Dent Mater. 2007 Nov;23(11):1332-41.
9. Addison O, Marquis PM, Fleming GJ. Resin strengthening of dental ceramics-the impact of surface texture and silane. J Dent. 2007 May;35(5): 416-24.
10. Addison O, Marquis P, Fleming G. The impact of cementation and storage variables on ceramic strengthening J Dent Res 2007; 96; Spec iss (abstr 0019)
11. Horn, H. R. A New Lamination: Porcelain Bonded to Enamel, NY State Dent J 49: 401-403; 1983
12. Simonsen R Calamia J. Tensile Bond Strength of Etched Porcelain, J Dent Res 62:297, Spec Iss. Abstr. No. 1154 (AADR). 1983
13. Stangel I, Nathanson D, Hsu C. Shear Strength of the Composite Bond to Etched Porcelain J Dent Res 66(9):1460-1465, 1987
14. Chen J, Matsumura H, Atsuta M. . Effect of etchant, etching period, and silane priming on bond strength to porcelain of composite resin. Oper Dent. 1998 Sep-Oct;23(5):250-7
15. Gler AU, Yilmaz F, Ural C, Gler E. Evaluation of 24-hour shear bond strength of resin composite to porcelain according to surface treatment. Int J Prosthodont. 2005 Mar-Apr; 18(2):156-60.
16. Nagayassu MP, Shintome LK, Uemura ES, Arajo JE. Effect of surface treatment on the shear bond strength of a resin-based cement to porcelain. Braz Dent J. 2006;17(4): 290-5.
17. Boscato N, Della Bona A, Del Bel Cury AA. Influence of ceramic pre-treatments on tensile bond strength and mode of failure of resin bonded to ceramics. Am J Dent. 2007 Apr;20(2): 103-8.
18. Peumans M, Hikita K, De Munck J, Van Landuyt K, Poitevin A, Lambrechts P, Van Meerbeek B. Effects of ceramic surface treatments on the bond strength of an adhesive luting agent to CAD-CAM ceramic. J Dent. 2007 Apr; 35(4):282-8.
19. Semmelman JO, Kulp PR. Silane bonding porcelain teeth to acrylic. J Am Dent Assoc. 1968 Jan;76(1): 69-73.
20. Myerson RL. J Am Dent Assoc. 1969 Jan;78(1): 1139. Effects of silane bonding of acrylic resins to porcelain on porcelain structure.
21. Newburg R, Pameijer CH. Composite resins bonded to porcelain with silane solution. J Am Dent Assoc. 1978 Feb;96(2):288-91.
22. Della Bona A, Anusavice KJ, Hood JA. Effect of ceramic surface treatment on tensile bond strength to a resin cement. Int J Prosthodont. 2002 May-Jun;15(3):248-53.
23. Filho AM, Vieira LC, Arajo E, Monteiro Jnior S. Effect of different ceramic surface treatments on resin microtensile bond strength. J Prosthodont. 2004 Mar;13(1):28-35.
24. Barghi N. To silanate or not to silanate: making a clinical decision. Compend Contin Educ Dent. 2000 Aug;21(8):659-62, 664.
25. Brentel AS, Ozcan M, Valandro LF, Alara LG, Amaral R, BottinoMA Microtensilebondstrengthofaresin cement to feldpathic ceramic after different etching and silanization regimens in dry and aged conditions. Dent Mater. 2007 Nov;23(11):1323-31.
26. Kanca J, Greitzer G. In-vitro comparison of ceramic bonding systems J Dent Res 2007; 96 ; Spec Iss (Abstr 1382).
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The use of sandblasting alone has been shown to improve bond strengths to porcelain
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Interface can be used to treat porcelain prostheses being inserted and can be used for ceramic repairs
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Success can be obtained if proper and effective protocols are utilized and kept fairly simple
