IADR Abstract Archives
Effect of Eggshell-derived Hydroxyapatite Incorporation into Adhesive on Bond Strength
Objectives: To evaluate the effect of adding eggshell-derived hydroxyapatite particles to a universal adhesive system on the microtensile bond strength and hybrid layer quality.
Methods: Extracted caries-free human molars (n=10/group) were coronally sectioned and flattened with 320-grit SiC to expose midcoronal dentin and randomly divided into three groups. Eggshell-derived hydroxyapatite particles (ED-HAP) were prepared and added in 0.15 wt%, 0.5 wt% to a universal bonding agent (Scotchbond Universal, 3M ESPE). After 35% phosphoric acid- etching for 10sec, universal bonding agent was applied, light-cured for 10sec using Elipar™ DeepCure-S LED Curing Light and restored with composite resin (Grandio, VOCO), shade A3 incrementally to a height of 4mm. Each increment was light-cured for 20sec. The specimens were sectioned into composite-dentin beams (0.9X0.9mm) and water-stored for 24h at 37°C. The microtensile bond strength testing (µTBS) was carried out at a crosshead speed of 0.5mm/min using the Universal Test Machine “Shimadzu-Autograph AGS-X”. Additional specimens (n=3/group) were immersed in silver nitrate for nanoleakeage (NL) analysis and evaluated with SEM. The data were analyzed using ANOVA and Tukey’s test (α=0.05).
Results: The initial mean±SD µTBS ranged between 43.2 (±6.8) MPa for control and between 39.8 (±9.6) to 41.4 (±3.75) MPa for ED-HAP modified groups. No significant differences were observed between 24h µTBS of control vs ED-HAP modified groups (p>0.05). In line with bond testing, no difference was found in NL of ED-HAP modified groups compared to control. (p>0.05).
Conclusions: Eggshell-derived hydroxyapatite particles incorporation into the adhesive system does not adversely affect the immediate bond strength. Further studies are needed to evaluate the effect on the long term.
Methods: Extracted caries-free human molars (n=10/group) were coronally sectioned and flattened with 320-grit SiC to expose midcoronal dentin and randomly divided into three groups. Eggshell-derived hydroxyapatite particles (ED-HAP) were prepared and added in 0.15 wt%, 0.5 wt% to a universal bonding agent (Scotchbond Universal, 3M ESPE). After 35% phosphoric acid- etching for 10sec, universal bonding agent was applied, light-cured for 10sec using Elipar™ DeepCure-S LED Curing Light and restored with composite resin (Grandio, VOCO), shade A3 incrementally to a height of 4mm. Each increment was light-cured for 20sec. The specimens were sectioned into composite-dentin beams (0.9X0.9mm) and water-stored for 24h at 37°C. The microtensile bond strength testing (µTBS) was carried out at a crosshead speed of 0.5mm/min using the Universal Test Machine “Shimadzu-Autograph AGS-X”. Additional specimens (n=3/group) were immersed in silver nitrate for nanoleakeage (NL) analysis and evaluated with SEM. The data were analyzed using ANOVA and Tukey’s test (α=0.05).
Results: The initial mean±SD µTBS ranged between 43.2 (±6.8) MPa for control and between 39.8 (±9.6) to 41.4 (±3.75) MPa for ED-HAP modified groups. No significant differences were observed between 24h µTBS of control vs ED-HAP modified groups (p>0.05). In line with bond testing, no difference was found in NL of ED-HAP modified groups compared to control. (p>0.05).
Conclusions: Eggshell-derived hydroxyapatite particles incorporation into the adhesive system does not adversely affect the immediate bond strength. Further studies are needed to evaluate the effect on the long term.