Effect of recasting percentage of base metal alloys on the metal-ceramic bond strength

Amaç: Metal seramik restorasyonların uzun dönem başarısı metal seramik bağlantısına bağlıdır. Ekonomik sebeplerle, metal destekli restorasyonlarda genellikle artık metalin tekrar kullanımı yapılmaktadır. Bu çalışmanın amacı, Co-Cr alaşımlarda artık metal kullanım yüzdelerinin metal-seramik bağlantısına olan etkisinin araştırılmasıdır. Gereç ve Yöntem: Yeni ve bir kez dökülmüş metallerin farklı yüzde kombinasyonları kullanılmış, her grupta 10 adet olmak üzere, toplamda 50 adet metal-seramik örnek elde edilmiştir. Beş mm yükseklik, 5 mm çapındaki metal disklerden guruplar sırasıyla, %100 yeni metal (G1), %75 yeni-%25 artık metal (G2), %50 yeni-%50 artık metal (G3), %25 yeni-%75 artık metal (G4), %100 artık metal (G5) kullanımıyla oluşturulmuştur. Opak ve dentin seramikleri 4 mm yükseklik, 4 mm çapında olacak şekilde metal örnekler üzerine pişirilmiştir. Örneklere 5-55 °C aralığında, 20 sn bekleme, 10 sn banyolar arası transfer ve 5000 siklüs olacak şekilde termal yaşlandırma yapılmıştır. Metal-seramik örneklere makaslama bağ dayanım testi 0.5 mm/dk çapraz hızla uygulanmıştır. Kırık tipleri ışık mikroskobu ile 20 büyütmede incelenmiştir. Elde edilen verilere Tek Yönlü Varyans ve Tukey testleri ile istatistiksel analiz uygulanmıştır (p=0,05).Bulgular: Gurupların ortalama makaslama bağ dayanımları sırasıyla; G1=80,67 MPa, G2=85,69 MPa, G3=81,25 MPa, G4=80,46 MPa, ve G5=81,74 MPa olarak bulunmuştur. Gurupların bağ dayanım değerleri arasında istatistiksel olarak anlamlı bir fark bulunmamıştır (p>0.005). Kırık tipleri tüm guruplar için kohezivdir.Sonuçlar: Çalışmamızın kısıtlamaları dahilinde, farklı oranlarla yeni metal ve bir kez dökülmüş artık metal içeren kıymetsiz alaşımlarının bağ dayanımları benzerdir

Kıymetsiz metal alaşımlarında artık metal kullanım yüzdesinin metal-seramik bağlantısına olan etkisi

Aim: Long-term success of metal ceramic restorations depends on metal ceramic bond. Recasting has been generally used for casted dental restorations in laboratories for economic reasons. This study was conducted to assess the effect of recasting percentage of Co-Cr alloys on the bond strength of metal-ceramic.Materials and Method: Different percentage combinations of new and once casted alloy were used to manufacture a total of fifty metal-ceramic samples for five groups (n=10). Metal discs (5 mm high-5 mm in diameter) were casted from 100% new alloy (G1), 75% new-25% once casted alloy (G2), 50% new-50% once casted alloy (G3), 25% new-75% once casted alloy (G4), 100% once casted alloy (G5). Opaque and dentin ceramics (4 mm high-4 mm in diameter) were fired on the metal samples. Metal-ceramic samples were thermo cycled (5-55 °C, 5000 cycles), with a dwell time of 20 s and a 10 s transfer time. The shear bond strength test was performed in a universal testing machine (Shimadzu) with a crosshead speed of 0.5 mm/min. Failure types were examined with a streomicroscope (X20). The data were analyzed with one-way ANOVA and the Tukey HSD test (p=0.05). Results: The mean bond strengths (MPa) were; 80.67 for G1, 85.69 for G2, 81.25 for G3, 80.46 for G4, and 81.74 for G5. No significant difference was found between the groups (p>0.005). Cohesive failure types were seen for all groups.Conclusion: Different percentages of new alloy and once casted alloy had similar bond strength values

PDF

___

1.Asgar K. Casting metals in dentistry: past--present--future. Adv Dent Res 1988; 2: 33-43.
2.Ayad MF. Compositional stability and marginal accuracy of complete cast crowns made with as-received and recast type III gold alloy. J Prosthet Dent 2002; 87: 162- 166.
3.Ucar Y, Aksahin Z, Kurtoglu C. Metal ceramic bond after multiple castings of base metal alloy. J Prosthet Dent 2009; 102: 165-171.
4.Reisbick MH, Brantley WA. Mechanical property and microstructural variations for recast low-gold alloy. Int J Prosthodont. 1995; 8: 346-350.
5.Akyil, M, Duymuş Z. Evaluation of the effect of recast metal addition, plating and oxidation temperature on metal-porcelain Bond strength in non-precious alloys. Clin Dent Res 2009, 33: 2-13.
6.Atluri KR, Vallabhaneni TT, Tadi DP, Vadapalli SB, Tripuraneni SC, et al. Comparative Evaluation of Metal-ceramic Bond Strengths of Nickel Chromium and Cobalt Chromium Alloys on Repeated Castings: An In vitro Study. J Int Oral Health 2014; 6: 99-103.
7.Madani AS, Rokni SR, Mohammadi A, Bahrami M. The effect of recasting on bond strength between porcelain and base-metal alloys. J Prosthodont 2011; 20: 190-194.
8.Henriques GE, Consani S, Rollo JM, Andrade e Silva F. Soldering and remelting influence on fatigue strength of cobalt-chromium alloys. J Prosthet Dent 1997; 78: 146- 152.
9.Kul E, Aladag LI, Duymus ZY. Comparison of the metal-ceramic bond after recasting and after laser sintering. J Prosthet Dent 2015; 114: 109-113.
10.Gupta S, Mehta AS. The effect of remelting various combinations of new and used cobalt-chromium alloy on the mechanical properties and microstructure of the alloy. Indian J Dent Res 2012; 23: 341-347.
11.Oyar P, Can G, Atakol O. Effects of environment on the release of Ni, Cr, Fe, and Co from new and recast Ni-Cr alloy. J Prosthet Dent 2014; 112: 64-69.
12.Ozdemir S, Arikan A. Effects of recasting on the amount of corrosion products released from two Ni-Cr base metal alloys. Eur J Prosthodont Restor Dent 1998; 6: 149-153.
13.Imirzalioglu P, Alaaddinoglu E, Yilmaz Z, Oduncuoglu B, Yilmaz B, et al. Influence of recasting different types of dental alloys on gingival fibroblast cytotoxicity. J Prosthet Dent 2012; 107: 24-33.
14.Yavuz T. Effect of surface treatment on elemental composition of recast NiCr alloy. Mater Sci Appl 2012; 3: 163-167.
15.Hesby DA, Kobes P, Garver DG, Pelleu GB Jr. Physical properties of a repeatedly used nonprecious metal alloy. J Prosthet Dent 1980; 44: 291-293.
16.Nelson DR, Palik JF, Morris HF, Comella MC. Recasting a nickel-chromium alloy. J Prosthet Dent 1986; 55: 122-127.
17.Vaillant-Corroy AS, Corne P, De March P, Fleutot S, Cleymand F. Influence of recasting on the quality of dental alloys: A systematic review. J Prosthet Dent 2015; 114: 205-211.e3.
18.Sipahi C, Ozcan M. Interfacial shear bond strength between different base metal alloys and five low fusing feldspathic ceramic systems. Dent Mater J 2012; 31: 333- 337.
19.do Prado RA, Panzeri H, Fernandes Neto AJ, das Neves FD, da Silva MR, et al. Shear bond strength of dental porcelains to nickel-chromium alloys. Braz Dent J 2005; 16: 202-206.
20.de Melo RM, Travassos AC, Neisser MP. Shear bond strengths of a ceramic system to alternative metal alloys. J Prosthet Dent 2005; 93: 64-69.
21.Joias RM, Tango RN, Junho de Araujo JE, Junho de Araujo MA, Ferreira Anzaloni Saavedra Gde S, et al. Shear bond strength of a ceramic to Co-Cr alloys. J Prosthet Dent 2008; 99: 54-59.
22.Akova T, Ucar Y, Tukay A, Balkaya MC, Brantley WA. Comparison of the bond strength of laser-sintered and cast base metal dental alloys to porcelain. Dent Mater 2008; 24: 1400-1404.