Effects of different surface modifications on micro-structure and adhesion of zirconia ceramic: an in vitro study

doi:10.7518/hxkq.2017.01.006

Abstract

Abstract:

Objective This study evaluated the effect of different mechanical-chemical surface treatments on the charac-teristics, microstructure, and composition of zirconia ceramics and on the zirconia-dentin adhesion. Methods The sintered commercial zirconia blocks (IPS e.max ZirCAD) were sectioned into 126 beams (6 mm×6 mm×5 mm) and randomly assigned to seven experimental groups (n=18). The zirconia block specimens were further treated as follows: (A) untreated, as control; (B) sandblasted with 50 μm Al₂O₃; (C) sandblasted with 50 μm Al₂O₃+30 μm silica powder; (D) sandblasted with 50 μm Al₂O₃+30% silica-sol coating; (E) sandblasted with 110 μm Al₂O₃; (F) sandblasted with 110 μm Al₂O₃+30 μm silica powder; and (G) sandblasted with 110 μm Al₂O₃+30% silica-sol coating. The surface roughness (R_a) of zirconia ceramics using X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) after seven surface treatments was analyzed. Seventy specimens of dentin surfaces were prepared. A dual-cure resin cement was applied into zirconia surfaces with its corresponding adhesive components to dentin. Shear bond strength (SBS) of each sample was measured using a universal testing machine. The data were analyzed by ANOVA using SPSS 17.0 software. Results Ra of zirconia were significantly different compared with the control group (P<0.05). The crystalline transformation from tetragonal phase to monoclinic phase was observed after surface modification. Monoclinic volume content of the heat-treated group was highest than that in other groups. The content of element Si in the heat-treated group was higher than that in other treatment groups accompanied by a decrease in elements Zr, Y, and Hf after being treated by two silica-coating methods. Air abrasion signifi-cantly increased the micro-cracks in the ceramic surface and caused the grain boundaries to disappear. A serious shrinkage of the thin silica film can be observed after sintering procedure. This process induced cracks and the film to strip away slightly from the surfaces of Y-TZP substrate. The SBS values from large to small were F and G groups, C and D groups, B and E groups (P<0.05), and control group (P<0.05). Conclusion Alumina sandblasting, silica powder abrasion, and silica-sol coating affect the surface morphology, structure, and composition of the tooth. This effect can also achieve the improved micro-mechanical interlocking or chemical bonding and finally increase the bond strength between zirconia and tooth. Alumina sandblasting followed by silica coating is an effective technique to increase the bonding strength between the zirconia ceramic and dentin.

Key words: zirconia, sandblasting, silica coating, surface roughness, phase transformation

CLC Number:

R783.2

Siwen Li, Shishi Li, Yanhong Wang, Hongmei. Ma. Effects of different surface modifications on micro-structure and adhesion of zirconia ceramic: an in vitro study[J]. West China Journal of Stomatology, 2017, 35(1): 43-50.

Figures/Tables 7

Fig 1

Tab 1

Fig 2

Fig 3

Fig 4

Fig 5

Fig 6

References 19

[1]	Vanderlei A, Bottino MA, Valandro LF.Evaluation of resin bond strength to yttria-stabilized tetragonal zirconia and fra-mework marginal fit: comparison of different surface condi-tionings[J]. Oper Dent, 2014, 39(1):50-63.
[2]	Kosmac T, Oblak C, Jevnikar P, et al.The effect of surface grinding and sandblasting on flexural strength and reliability of Y-TZP zirconia ceramic[J]. Dent Mater, 1999, 15(6):426-433.
[3]	马红梅, 李斯文, 贾兴亚, 等. Cerec AC椅旁即刻全瓷修复83例效果观察[J]. 中国实用口腔科杂志, 2015, 8(1):36-39.
	Ma HM, Li SW, Jia XY, et al.Clinical experience in Cerec AC chairside immediate all-ceramic restorations in 83 cases[J]. Chin J Pract Stomotol, 2015, 8(1):36-39.
[4]	Özcan M, Kerkdijk S, Valandro LF.Comparison of resin cement adhesion to Y-TZP ceramic following manufacturers’ instructions of the cements only[J]. Clin Oral Investig, 2008, 12(3):279-282.
[5]	Sasse M, Eschbach S, Kern M.Randomized clinical trial on single retainer all-ceramic resin-bonded fixed partial den-tures: influence of the bonding system after up to 55 months[J]. J Dent, 2012, 40(9):783-786.
[6]	Kern M.Bonding to oxide ceramics—laboratory testing versus clinical outcome[J]. Dent Mater, 2015, 31(1):8-14.
[7]	Bielen V, Inokoshi M, Munck JD, et al.Bonding effective-ness to differently sandblasted dental zirconia[J]. J Adhes Dent, 2015, 17(3):235-242.
[8]	Amaral M, Belli R, Cesar PF, et al.The potential of novel primers and universal adhesives to bond to zirconia[J]. J Dent, 2014, 42(1):90-98.
[9]	Inokoshi M, Vanmeensel K, Zhang F, et al.Aging resistance of surface-treated dental zirconia[J]. Dent Mater, 2015, 31(2):182-194.
[10]	张红, 景页, 聂蓉蓉, 等. 底涂剂的化学处理对二氧化锆陶瓷树脂粘接效果的影响[J]. 华西口腔医学杂志, 2015, 33(5):466-469.
	Zhang H, Jing Y, Nie RR, et al.Effect of a chemical primer on the bond strength of a zirconia ceramic with self-adhesive resin cement[J]. West Chin J Stomotol, 2015, 33(5):466-469.
[11]	Mutlu O, Renata MM, Rodrigo OAS, et al.Effect of air-particle abrasion protocols on the biaxial flexural strength, surface characteristics and phase transformation of zirconia after cyclic loading[J]. J Mech Behav Biomed Mater, 2013, 20(4):19-28.
[12]	Inokoshi M, De Munck J, Minakuchi S, et al.Meta-analysis of bonding effectiveness to zirconia ceramics[J]. J Dent Res, 2014, 93(4):329-334.
[13]	Söderholm KJ, Shang SW.Molecular orientation of silane at the surface of colloidal silica[J]. J Dent Res, 1993, 72(6):1050-1054.
[14]	Yang B, Barloi A, Kern M.Influence of air-abrasion on zir-conia ceramic bonding using an adhesive composite resin[J]. Dent Mater, 2010, 26(1):44-50.
[15]	Shiu P, De Souza-Zaroni WC, Eduardo Cde P, et al. Effect of feldspathic ceramic surface treatments on bond strength to resin cement[J]. Photomed Laser Surg, 2007, 25(4):291-296.
[16]	Conrad HJ, Seong WJ, Pesun IJ.Current ceramic materials and systems with clinical recommendations: a systematic review[J]. J Prosthet Dent, 2007, 98(5):389-404.
[17]	Hallmann L, Ulmer P, Reusser E, et al.Surface characteri-zation of dental Y-TZP ceramic after air abrasion treatment[J]. J Dent, 2012, 40(9):723-735.
[18]	Liu D, Tsoi JK, Matinlinna JP, et al.Effects of some che-mical surface modifications on resin zirconia adhesion[J]. J Mech Behav Biomed Mater, 2015, 46:23-30.
[19]	Chevalier J, Gremillard L, Deville S.Low-temperature degra-dation of zirconia and implications for biomedical implants[J]. Ann Rev Mater Sci, 2007, 37(1):1-32.

分组	Zr	Y	Hf	Al	Si	O
A	80.24±0.27	5.64±0.16	1.96±0.18	0.26±0.09	0.92±0.10	10.98±0.28
B	71.18±0.51	5.47±0.17	1.80±0.15	2.60±0.17	0.45±0.08	18.50±0.42
C	64.76±0.42	5.13±0.14	1.14±0.08	1.16±0.14	2.83±0.25	24.98±0.56
D	56.99±0.95	4.82±0.20	1.08±0.17	0.62±0.23	6.87±0.47	29.62±0.73
E	70.68±0.38	5.40±0.12	1.58±0.11	2.94±0.16	0.39±0.09	19.01±0.43
F	63.50±0.97	5.01±0.21	1.09±0.10	1.62±0.13	3.14±0.34	25.64±0.92
G	56.91±0.57	4.33±0.25	0.95±0.26	0.47±0.11	7.10±0.49	30.24±0.65