Comparative study between laser sintering and casting for retention of resin composite veneers to cobalt-chromium alloy

Abstract

The purpose of this study was to evaluate and compare the bond strengths between resin composite veneer and laser-sintered cobalt-chromium (Co-Cr) alloy with and without retention devices (Laser-R and Laser-N respectively). Cast Co-Cr alloy with and without retention devices (Cast-R and Cast-N respectively) were also prepared for fabrication technique comparison. Disk-shaped Co-Cr alloy specimens were air-abraded with alumina and veneered with a veneering system, Estenia C&B (ES) or Ceramage (CE). After 20,000 thermocycles, tensile testing was performed. Data were analyzed by ANOVA and multiple comparison test. When no retention devices were present, no significant differences were observed between Laser-N/ES and Cast-N/ES, or between Laser-N/CE and Cast-N/CE, but ES exhibited significantly higher bond strength than CE. With retention devices, Laser-R/ES, Cast-R/ES and Laser-R/CE showed no significant differences, and their retention strengths were significantly higher than that of Cast-R/CE. Compared to cast Co-Cr alloy, laser-sintered Co-Cr alloy with retention devices provided better retention durability for resin composite-veneered prostheses.

Bond strengths between gingiva-colored layering resin composite and zirconia frameworks coated with feldspathic porcelain

“…Bond strength was higher for the photo/heat-polymerized (EST) gingiva-colored indirect resin composite than for the light-polymerized (CER) gingiva-colored indirect resin composite in all groups. These results are consistent with those of previous studies of bonding between indirect resin composites and metal alloys, which found photo/heatpolymerized indirect resin composites provided higher bond strengths than did light-polymerized indirect resin composites 25,26) , perhaps due to differences in the size of filler particles, the type of polymerization, and the mechanical properties of gingiva-colored indirect resin composites. Magne et al 27) reported that microtensile bond strengths between resin composites and resinluting material were affected by improved mechanical properties caused by heat treatment.…”

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).…”

Retention strength between veneering resin composites and laser-sintered cobalt–chromium alloy

“…Eight specimens for each test group were thermocycled 20,000 times alternately between water baths held at 4 and 60°C, with a 1 min dwell time in each bath. Prior to tensile testing, cylindrical stainless steel rods (30.0 9 8.0 mm diameter) were bonded to the veneered The stainless steel rods were used to provide a handle for the tensile testing based on the procedure described in a previous report [25]. Tensile retention strengths were determined using a universal testing machine (AGS-10kNG: Shimadzu Corp., Kyoto, Japan) at a crosshead speed of 1.0 mm/min.Tensile retention strength was defined as the force at failure divided by bonded surface area (2.5 9 2.5 9 3.14 mm 2 ).…”

“…The authors previously reported that laser-sintered Co-Cr alloy specimens with retention devices provided better retention and higher retention strength than cast Co-Cr alloy specimens with retention beads [25]. However, little information is available on adhesive bonding between laser-sintered CoCr alloy and various resin composite veneering systems.…”

“…Several studies have revealed that priming with 10-methacryloyloxydecyl dihydrogen phosphate (MDP) significantly improved the retention strength between some resin-based materials and cast Co-Cr alloy [17][18][19][20][21][22][23][24][25]. The authors previously reported that laser-sintered Co-Cr alloy specimens with retention devices provided better retention and higher retention strength than cast Co-Cr alloy specimens with retention beads [25].…”