IADR Abstract Archives
The Mechanical and Adhesive Properties of Three Self-Adhesive Resin Cements
Objectives: This study investigated three self-adhesive resin cements (G-CEM ONE (GO), Panavia SA Cement Universal (PU), and RelyX Universal (RU)) on their self-cure mode (i.e. without light-cure) performance. The fracture toughness (KIc), mould-enclosed shear bond strength (ME-SBS), and wear resistance were compared.
Methods: 180 KIc samples (n=10) were prepared in a custom-made PTFE mould in accordance to ASTM-E399 pre-cracked disk-shaped compact specimen. Samples were stored in either DI-water or 0.01mol% lactic acid for 1, 14 and 28-day(s). For ME-SBS test, the three resin cements were bonded with mid-coronal dentine surfaces with their respective primers in Ø3-mm stainless rods (n=5) after (1) 10-mins from sample preparation, (2) 1-day storage in a 37°C incubator, or (3) thermocycling (5-55°C/10,000-cycles). Fifteen disk-shaped samples (Ø6-mm, 2-mm thickness, n=5) were prepared, and 3-body wear was performed under 50N load for 10,000-cycles at 1.2Hz.
Results: For KIc, 3-way ANOVA revealed cement type (GO>PO>RU) and storage time were significant (p<0.001) influencing factors, while solution type was not (p=0.254). GO and RU have no statistical significance on mean KIc over the storages. However, PU shows unstable KIc (significant rise at day 14 and drop at day 28), particularly after 28 days acid storage (0.29±0.09MPa●m½, p=0.005). Interestingly, RU needs to wait 30+mins in order to remove them successfully from the PTFE mould, while others need 5-10-mins. Only GO can bond with dentine in 10-mins after cementation with ME-SBS 2.41±0.33MPa. After wear, RU had significantly lower surface roughness increases than GO (p=0.007) and PU (p=0.001), whilst GO had significantly lower scratch depth compared with PU (p=0.003) and RU (p<0.001).
Conclusions: GO could achieve the highest ME-SBS and faster initial bond to dentine due to touch-cure after primer application. It also showed high KIc and lowest wear depth among three groups make it suitable for fibre posts, thick or opaque restorations in which light-curing efficiency is affected.
Methods: 180 KIc samples (n=10) were prepared in a custom-made PTFE mould in accordance to ASTM-E399 pre-cracked disk-shaped compact specimen. Samples were stored in either DI-water or 0.01mol% lactic acid for 1, 14 and 28-day(s). For ME-SBS test, the three resin cements were bonded with mid-coronal dentine surfaces with their respective primers in Ø3-mm stainless rods (n=5) after (1) 10-mins from sample preparation, (2) 1-day storage in a 37°C incubator, or (3) thermocycling (5-55°C/10,000-cycles). Fifteen disk-shaped samples (Ø6-mm, 2-mm thickness, n=5) were prepared, and 3-body wear was performed under 50N load for 10,000-cycles at 1.2Hz.
Results: For KIc, 3-way ANOVA revealed cement type (GO>PO>RU) and storage time were significant (p<0.001) influencing factors, while solution type was not (p=0.254). GO and RU have no statistical significance on mean KIc over the storages. However, PU shows unstable KIc (significant rise at day 14 and drop at day 28), particularly after 28 days acid storage (0.29±0.09MPa●m½, p=0.005). Interestingly, RU needs to wait 30+mins in order to remove them successfully from the PTFE mould, while others need 5-10-mins. Only GO can bond with dentine in 10-mins after cementation with ME-SBS 2.41±0.33MPa. After wear, RU had significantly lower surface roughness increases than GO (p=0.007) and PU (p=0.001), whilst GO had significantly lower scratch depth compared with PU (p=0.003) and RU (p<0.001).
Conclusions: GO could achieve the highest ME-SBS and faster initial bond to dentine due to touch-cure after primer application. It also showed high KIc and lowest wear depth among three groups make it suitable for fibre posts, thick or opaque restorations in which light-curing efficiency is affected.