Enhancement of the Bonding Durability of Resin-based Cement to Lithium Disilicate Glass Ceramics Using Surface Modification Methods

Abstract

: The aim of the present study was undertaken to investigate the effects of several surface modi cation methods applied to lithium disilicate glass ceramics LDCs on their bonding durability with resin-based cement. The LDC specimens were sectioned using a low-speed diamond cutting machine, crystallized by heating in a furnace, and then subjected to several surface modi cation treatments such as acid etching, sandblasting, or silica coating with silane coupling agents. Then, a cylindrical titanium with a sandblasted surface was bonded to the surface-modi ed LDC specimens using resin-based cement. After being either stored in water at 37 C for 24 h or subjected to 10,000 and/or 30,000 thermal cycles, the specimens were subjected to a shear bond strength test using a universal testing machine. The surface-modified LDC specimens obtained by combining blasting and silica coating modi cation treatments showed excellent durability, similar to that of acidetched specimens. For safer laboratory practice, we recommend using the silica coating method for LDCs prior to applying silane coupling agents.

Effect of different silane coupling agents on the wettability and shear bond strength between glass ceramic and resin cement

“…In contrast, Sato et al (43) reported that application of silane coupling agent alone on the surface of lithium disilicate was not useful due to the debonding of specimens after themocycling. The author suggested alternative method apart from using hydrofluoric acid and encouraged the use of additional treatment along with silanization such as special gas emission method and tribochemical treatment with phosphoric acid ester monomer to enhance the activation effect of silane coupling agent.…”

“…Group 1: Treat with hydrofluoric acid and silane coupling agent; Group 2: Treat with silane coupling agent; Group 3: Treat with hydrofluoric acid alone. (Filho et al, 2004) (38) .................. 33 (43) ..................... 33 Table 10 Shear bond strengths of the non-modified and modified LDC specimens. In the table supplied, across a particular row, samples denoted by the same superscript letters are not significantly different (P > 0.05).…”

“…Across a particular column, samples denoted by the same subscripted letters are not significantly different (P > 0.05). (Sato et al, 2015) (43) 11 Average contact angles (standard deviations) in degree (°) of various silanized groups. (Banthitkhunanon P., 2017) (47) (51) (53) 19 Means and standard deviation of bond strength data (MPa) as a function of storage condition, total number of tested samples in conditions without and with aging, total number of pre-tested failures (PTF) during thermocycling (TC), contact angle, and roughness (Sa and Sz parameters in nm) (Prochnow et al, 2018) (10) ......... (44) .... 23 Average contact angle of respective silane group in degree (°) on hydrofluoric-acid-etched and unetched lithium disilicate glass ceramic disks ..............…”

“…In the table supplied, across a particular row, samples denoted by the same superscript letters are not significantly different (P > 0.05). Across a particular column, samples denoted by the same subscripted letters are not significantly different (P > 0.05) (Sato et al, 2015) (43). a 11.8 (4.7) a 21.1 (4.6) b 41.5 (6.8) c A 56.5 (9.1) d A 43.6 (8.3) c A 60.3 (9.0) d A TC10000 Debonding Debonding Debonding 61.2 (6.6) e B 54.5 (3.1) e A 33.5 (3.2) f A 62.6 (6.2) e A TC30000 Debonding Debonding Debonding 51.4 (6.1) g AB 58.7 (8.3) g A 36.4 (5.4) h A 54.6 (7.1) g A…”