Surface treatments on CAD/CAM glass–ceramics: Influence on roughness, topography, and bond strength

Abstract

Objective To evaluate the influence of surface treatment on roughness (SA), topography, and shear bond strength (SBS) of computer‐aided designer and manufacture (CAD/CAM) zirconia‐reinforced lithium silicate (ZLS) and feldspathic (FEL) glass–ceramics. Materials and methods FEL and ZLS specimens were submitted to 5% or 10% hydrofluoric acid (HF) or self‐etching ceramic primer (MEP) and different application times (20, 40, and 60 s), or to sandblasting (Control, 20 s). Resin cement cylinders were bonded to the specimens and tested in shear (n = 10) after 24 h and 16‐months of water storage. SA and topography were evaluated by atomic force (AFM, n = 10) and scanning electron microscopy. Data were analyzed by ANOVA and Bonferroni test (α = 0.05). Results Sandblasting promoted the highest SA for ZLS, but 10% HF (40, 60 s) promoted higher SBS at 16 months. 10% HF produced the highest SA for FEL, but sandblasting and 5% HF (20 s) maintained SBS after 16 months, without differences from 10% HF (20 s) (p > 0.05). Overall, MEP produced lower SA and SBS among groups (p < 0.05). HF displayed greater morphological changes on FEL. Conclusion 10% HF (40 s) provided better results for ZLS, while 5% or 10% HF (20 s) was suitable for FEL. Clinical significance Surface treatments influenced SA, topography, and SBS of materials. HF etching is the surface treatment of choice for both CAD/CAM glass–ceramics.

Comparison of the Micro-Shear Bond Strength of Resin Cements to CAD/CAM Glass Ceramics with Various Surface Treatments

“…The roughness values obtained with CJ and SB are higher than with HF. A previous study reported that no relationship could be established between surface roughness and bond strength in zirconia-reinforced lithium silicate ceramics [ 51 ]. In the present study, similar with the results in the literature [ 46 , 47 , 51 , 52 , 53 ], while the highest roughness values were obtained by sandblasting, the highest bond strength values were seen in the HF group for VS, and the other two ceramics.…”

“…A previous study reported that no relationship could be established between surface roughness and bond strength in zirconia-reinforced lithium silicate ceramics [ 51 ]. In the present study, similar with the results in the literature [ 46 , 47 , 51 , 52 , 53 ], while the highest roughness values were obtained by sandblasting, the highest bond strength values were seen in the HF group for VS, and the other two ceramics. Sandblasting processes may cause crack formation and weakening of the ceramic structure by creating deep, irregular pits on the surface of glass ceramics, which do not present retentional features.…”

Influence of surface treatments and adhesive protocols on repair bond strength of glass‐matrix and resin‐matrix CAD/CAM ceramics

“…Previous research revealed that in macro-shear bond strength tests, with a relatively larger bonded area of up to 3 mm 2 , stress focuses on the area where the force is applied, resulting in uneven stress distribution and cohesive failures in ceramics, but in μSBS test, due to the reduced bonded area of 1 mm 2 , stress is distributed more homogeneously. 17,40 Furthermore, the micro-tensile bond strength test requires technical sensitivity, otherwise, it can cause a high frequency of premature failures and microcracks within the specimen. 10,40 Moreover, it can be influenced by the cutting speed, shape, and brittleness of the sample.…”

“…The reliable and durable bonding of different materials to each other has long been a goal in the field of dentistry. To ensure adequate bond strength between inert restorative materials and resin composites, it is recommended to employ mechanical or chemical surface treatments 13–20 . These treatments aim to enhance the bonding capability by modifying the surface properties of the restorative materials.…”

“…To ensure adequate bond strength between inert restorative materials and resin composites, it is recommended to employ mechanical or chemical surface treatments. [13][14][15][16][17][18][19][20] These treatments aim to enhance the bonding capability by modifying the surface properties of the restorative materials. As a method of mechanical surface treatment, sandblasting with aluminum oxide (AL) has been used for years as a practical method, and it is recommended especially for resin-matrix ceramics.…”