An in vitro evaluation of the effect of sandblasting and laser surface treatment on the shear bond strength of a composite resin to the facial surface of primary anterior stainless steel crowns

Abstract

Objectives: The present study was conducted to evaluate the optimal method of enhancing the bond strength of a composite resin to the facial surface of the primary anterior stainless steel crowns using various surface treatments namely Nd: YAG laser surface treatment, sandblasting , alloy primer application and no surface treatment. Study Design: The study sample consisted of 60 primary anterior stainless steel crowns (UnitekTM size R 4), with 15 samples randomly divided into the 4 study groups, embedded in acrylic blocks. The facial surface of these surface treated crowns was utilized as the bonding surface to which 2.5mm diameter composite resin cylinders were bonded for the evaluation of the shear bond strength. Shear bond strength measurements were made using a universal testing machine utilizing a shearing blade (jig).The mode of failure at composite-metal interface was determined using a Stereomicroscope at 10 X magnification. Results: The mean bond strength values obtained for surface treatment of Nd: YAG laser surface treated, Sandblasting ,Alloy Primer and No surface treatments were 17.01±.92 , 13.18 ± .73, 7.46 ± .70 and 7.33 ± .77 MPa respectively. The obtained bond strength values were subjected to a one way ANOVA and a Scheffe’s post-hoc comparison test. The results of the present study indicated that Laser surface treatment of the facial surface of the crowns enhanced the bond strength of the composite resin significantly compared to the other groups. Conclusions: Nd: YAG laser surface treatment produced an excellent surface roughness and obtained the highest shear bond strength values suggestive for recommendation as an optimal surface treatment to be used to enhance the resin-metal bond at the interface of the composite resin and the facial surface of primary anterior stainless steel crowns for the purpose of chairside veneering. Key words:Nd: YAG laser treatment, Sandblasting, Primary anterior stainless steel crown, Chairside veneering, Enhancing Resin-Metal Bond, Early childhood caries, Shear bond strength (SBS).

Shear bond strength of veneer composite to cobalt-chromium alloys fabricated differently

“…Actually, many studies have shown that metalresin bonding is generally affected by surface treatments of the bonding area and adhesive systems (13)(14)(15)(16)(17). To enhance metal-resin bonding, retention beads are frequently used and are suggested in metal-resin restorations, but macromechanical retention devices have many disadvantages, such as causing an overcontoured resin veneered restoration or an unpleasing esthetic result caused by reverberating of the retention beads under the composite veneer (13,16,18). In this study, no macro-mechanical retention devices were used because the aim of this study was to assess and compare showed that metal substructures with retention devices fabricated by laser sintering (DMLS) had higher SBS values than those fabricated by casting, while there were no statistical differences between the two techniques when the metal specimens were prepared without retention devices (18).…”

“…Similar to the results of the present study, there were no significant differences between the casting and the DMLS groups. Generally, SBS tests are used for evaluating bonding strengths in in-vitro studies, as the shear forces simulate the occlusal contact forces in the masticatory system (13)(14)(15)(16)(17); (20)(21)(22). As previous studies have revealed, the surface characteristics of the bonding area affects the SBS values (14)(15)(16)(17).…”

Bonding Strength of Ceromer with Direct Laser Sintered, Ni-Cr-Based, and ZrO2 Metal Infrastructures After Er:YAG, Nd:YAG, and Ho:YAG Laser Surface Treatments—A Comparative In Vitro Study

“…16,21,10 Bond strength can be improved by the presence of micromechanical retention, as the creation of roughened metal surfaces may allow ceromer to penetrate into pits and fissures, thereby creating a stronger micromechanical interlock. The roughness of metal surface changes in accordance with the several characteristics of metal and applied FIG.…”

“…[15][16][17] Surface treatments increase the available surface for adhesion; however, the application of every routine method has advantages and disadvantages in several types of metal infrastructures, and there is a need for more adjusted and predictable surface changes. Currently available treatments provide variable success after their application to the several types of dental materials.…”

“…In prosthodontics, one of the important needs is the satisfactory bonding of ceromer to the metal infrastructures, considering the aesthetic satisfaction, strong stability and shear resistance, and longevity of the restorations. 14,16,[18][19][20] Laser surface treatment modalities make easier the surface modification procedure and also have the potential of enabling the performance of controlled micro-topographic modifications, because the depth of optical penetration of a laser depends on its properties and on the material irradiated. Previous studies have evaluated the effect of laser surface modifications using Er:YAG, Nd:YAG, Ho:YAG, or Femtosecond.…”