Fracture Resistance of New Metal-Free Materials Used for CAD-CAM Fabrication of Partial Posterior Restorations
Abstract
:1. Introduction
2. Materials and Methods
3. Results
4. Discussion
5. Conclusions
- The CAD-CAM restoration materials analyzed showed high fracture resistance values that were adequate for use in partial coverage dental restorations in the posterior region.
- IPS e.max CAD® ceramic obtained the highest fracture resistance, although Weibull distribution showed that it had less predictable behavior than the other materials tested.
- Hybrid materials presented lower fracture resistance than ceramic materials due to their internal composition.
- The resilient behavior exhibited by hybrid materials generated surface wear patterns prior to fracture, which implied more conservative behavior than ceramic materials.
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Group | Material | Type | Manufacturing Data | Chemical Composition | Properties | Characteristics/ Lot nº |
---|---|---|---|---|---|---|
LDS group (GC) | IPS e.max CAD® | High-strength ceramic | Ivoclar Vivadent, Schaan, Liechtenstein | Crystalline phase: 70% lithium disilicate | Fracture resistance 360 MPa Elasticity modulus (95 GPa) Poisson modulus 0.25 Marginal fit 0.06 mm Acid-sensitive | U40015 U40016 MT BL4/C14 |
ZRLS group | VITA SUPRINITY® | High-strength ceramic | VITA Zahnfabrik, Bad Zäckingen, Germany | Crystalline phase: 64% lithium silicate 15% lithium disilicate 10% zirconium dioxide Glass-ceramic matrix | Fracture resistance 420 MPa Elasticity modulus (70 GPa) Poisson modulus 0.23 Marginal fit 0.06 mm Acid-sensitive | 74740 74742 A2-HT PC-14 |
PICN group | VITA ENAMIC® | Hybrid material: PICN | VITA Zahnfabrik, Bad Zäckingen, Germany | Glass-ceramic matrix: 86% conventional feldspathic ceramic (leucite and zirconia) Organic phase: 14% UDMA and TEGDMA | Fracture resistance 160 MPa Elasticity modulus (30 GPa) Poisson modulus 0.23 Acid-sensitive | 56171 82120 1M1-HT EMC-14 |
RNC group | LAVA™ ULTIMATE | Hybrid material: RNC | 3M ESPE, St Paul, Minn, USA | Crystalline phase: 80% Nanoceramic (silica and zirconia) Organic matrix: 20% organic filling | Fracture resistance 250 MPa Elasticity modulus (12.77 GPa) Poisson modulus 0.30 Marginal fit 0.01 mm Acid-resistant | N429938 N429987 A3-LT/14 |
Group | Material and Cementation Procedure | Type | Chemical Composition | Duration | Manufacturer | Lot No. |
---|---|---|---|---|---|---|
LDS group (CG) | 1. IPS Ceramic Etching Gel® | Acid etching for ceramic | 4.9% hydrofluoric acid | 20’ | Ivoclar Vivadent | T76221 |
2. IPS Ceramic Neutralizing Powder® | Neutralizing powder | Sodium carbonate 25%–50%, calcium carbonate 25%–50%. | 20’ | Ivoclar Vivadent | V47224 | |
3. Monobond Plus® | Silane | Adhesive monomers 4%, ethanol 96% | 60’ | Ivoclar Vivadent | X43365 | |
1. Excite DSC® a | Adhesive agent | Phosphonic acid acrylate, dimethacrylates, hydroxyethyl methacrylate, highly dispersed silicon dioxide, ethanol, catalysts, stabilizers, and fluoride | 20’ rub 20’ light-cure | Ivoclar Vivadent | Z33289 | |
2. Variolink Esthetic DC Neutral® | Dual-cure resin cement | Barium glass filling, mixture of oxide 52.2%, dimethacrylate 22%, high dispersión silica, ytterbium trifluoride 25%, initiators and stabilizers 0.8%, pigments <0.1% | 20’ light-cure each face | Ivoclar Vivadent | W95564 W95566 | |
3. Liquid Strip® | Glycerine | Glycerine gel | 20’ | Ivoclar Vivadent | K44713 | |
ZRLS group / PICN group | 1. Vita Ceramics Etch® | Acid etching for ceramic | 5% hydrofluoric acid | 60’ | VITA Zahnfabrik | G32613 |
2. VITASIL® | Silane | 3-methacryloxypropyltrimethoxysilane, ethanol, and water | 60’ | VITA Zahnfabrik | I18532 | |
3. Vita A.R.T Bond® b | Adhesive agent | Bond: methacrylate 97%–99% and polyalkenoate 1%–3% Primer A: water 96%–98%, sodium fluoride <0.1%, organic substances 2%–4% Primer B: methacrylate 89%–91%, polyalkeonate 6%–8%, water 2%–4% | 20’ primer 20’ light-cure adhesive | VITA Zahnfabrik | H15866 | |
4. Vita DUO CEMENT® | Resin cement dual | Methyl methacrylate 28%–32%, inorganic components 63%–77% | 20’ light-cure each face | VITA Zahnfabrik | F72605 | |
RNC group | 1. Cojet Prep® | Sandblasting | Aluminium particles, particle size: 30 μm, pressure 2.0 bars | 30’ | 3M ESPE | |
2. Scotchbond™ Universal Adhesive c | Universal adhesive agent | BisGMA, HEMA, decamethylene dimethacrylate, ethanol, water, silane-treated silica, 2-propenoic acid, methacrylated phosphoric acid, copolymer of acrylic and itaconic acid, ethyl-4-dimethylaminobenzoat, camphorquinone, (dimethylamino) ethyl methacrylate, methyl ethyl ketone | 20’ rub 20’ light-cure | 3M ESPE | 4636134 | |
3. RelyX ™ Ultimate | Dual-cure resin cement | Base paste: silane-treated glass powder, 2-propenoic acid, 2-methyl, reaction products with 2-hydroxy-1,3-propanedyl dimethacrylate and phosphorus oxide, TEGDMA, silane-treated silica, oxide glass chemicals, sodium persulfate, tertbutyl peroxy-3,5,5- trimethylhexanoate, copper acetate monohydrate Catalyst paste: silane-treated glass powder, substituted dimethacrylate, 1,12-dodecane dimethacrylate, silane-treated silica, 1-benzyl-5-phentyl-barbic-acid, calcium salt, sodium p-toluenesulfinate, 2-propenic acid, 2-methyl-, di-2,1-ethanediyl ester, calcium hydroxide, titanium dioxide | 20’ light-cure each face | 3M ESPE | 4751433 | |
Tooth | 1. Scotchbond™ Universal Etchand | Acid etching agent Tooth | 3 mL 37.5% orthophosphoric acid | 15’ dentin 30’ enamel | 3M ESPE | 4638524 |
2. Adhesive recommended for each material a,b,c |
Groups | ||||
---|---|---|---|---|
LDS Group (Control Group) | ZRLS Group | PICN Group | RNC Group | |
N | 20 | 20 | 20 | 20 |
σ (MPa) | 4588.6 | 4476.3 | 4014.2 | 3110.0 |
σf ± SD | 1843.5 | 762.6 | 681.1 | 169.0 |
95% CI of mean | 3725.8–5451.4 | 4119.4–4833.2 | 3695.5–4333.0 | 3030.9–3189.1 |
Minimum (MPa) | 1784.1 | 2919.4 | 2775.7 | 2864.1 |
Maximum (MPa) | 7277.9 | 5913.2 | 5344.3 | 3537.5 |
Median (MPa) | 4508.2 | 4659.4 | 3925.1 | 3058.3 |
m | 2.36 | 6.32 | 6.11 | 16 |
R2 | 0.97 | 0.942 | 0.971 | 0.636 |
Fracture Type | LDS Group (CG) | ZRLS Group | PICN Group | RNC Group | |
---|---|---|---|---|---|
Adhesive | 0 | 0 | 0 | 0 | |
Cohesive | Indentation | 0 | 0 | 16 (80%) | 15 (75%) |
Radial | 19 (95%) | 20 (100%) | 16 (80%) | 15 (75%) | |
Complete | 1(5%) | 0 | 4 (20%) | 5 (25%) |
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García-Engra, G.; Fernandez-Estevan, L.; Casas-Terrón, J.; Fons-Font, A.; Castelo-Baz, P.; Agustín-Panadero, R.; Román-Rodriguez, J.L. Fracture Resistance of New Metal-Free Materials Used for CAD-CAM Fabrication of Partial Posterior Restorations. Medicina 2020, 56, 132. https://doi.org/10.3390/medicina56030132
García-Engra G, Fernandez-Estevan L, Casas-Terrón J, Fons-Font A, Castelo-Baz P, Agustín-Panadero R, Román-Rodriguez JL. Fracture Resistance of New Metal-Free Materials Used for CAD-CAM Fabrication of Partial Posterior Restorations. Medicina. 2020; 56(3):132. https://doi.org/10.3390/medicina56030132
Chicago/Turabian StyleGarcía-Engra, Georgina, Lucia Fernandez-Estevan, Javier Casas-Terrón, Antonio Fons-Font, Pablo Castelo-Baz, Rubén Agustín-Panadero, and Juan Luis Román-Rodriguez. 2020. "Fracture Resistance of New Metal-Free Materials Used for CAD-CAM Fabrication of Partial Posterior Restorations" Medicina 56, no. 3: 132. https://doi.org/10.3390/medicina56030132