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Ultrafine ceramic restoration behavior under fatigue bonded in posterior teeth
d e n t a l m a t e r i a l s 3 3 S ( 2 0 1 7 ) e1–e92
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Ultrafine ceramic restoration behavior under fatigue bonded in posterior teeth
Incorporating compounds in restorative materials that modify streptococcus mutans virulence
F.O. Abu-Izze ∗ , G.F. Ramos, L.C. Anami, M.A. Bottino São Paulo State University – UNESP, Brazil Purpose/aim: Restorations in thin thicknesses have been used as a form of minimally invasive clinical approach. The aim of this study was to compare hybrid and ceramic crowns according to the thickness of the posterior restoration under fatigue loading. Materials and methods: To evaluate the fatigue behavior of these restorations, 60 standard preparations were machined in G10 resin, and 60 partial table top restorations of different thicknesses (0.5 and 1.0 mm) were machined. After scanning a master preparation in the model and scanning the restoration waxing, they were machined by Cerec 3 CAD/CAM system (Cerec v3.03; Syrona Dental Systems GmbH, Bensheim, Germany) in ceramic-based lithium silicate reinforced by zirconia (SUP – Suprinity Vita) and polymer-infiltrated ceramic (EN – Enamic Vita); both, Vita Zahnfabrik, Bad Sackingen, Germany). From each material, 15 sets of G10 preparations and respective restorations with thickness 0.5 or 1.0 mm were obtained, generating the four groups: SUP.5, SUP1, EN.5, and EN1. After finishing and polishing, the restorations were cleaned in an ultrasonic bath with isopropyl alcohol for 10 min. SUP restorations were crystallized according to the manufacturer’s recommendations. The samples were then bonded to the G10 preparations using Panavia F 2.0 (Kuraray Noritake, Okayama, Japan). From the mean values of maximum load for compression fracture (n = 3), the parameters for stepwise stress fatigue test were determined. The test evaluated the fatigue strength (n = 12) of the restorations submitted to the load of 450 N during the mechanical cycles. By the number of mechanic cycles at 450 N required for the fracture of the specimens or considered the test suspended upon reaching 1,5 × 106 cycles. The presence of cracks and/or fractures was checked with interruption of the test and adequate light, and evaluated in a stereomicroscope every 5 × 105 cycles. The failure modes of all specimens were checked and representative samples were also evaluated in scanning electron microscopy. Results: The comparison between the experimental groups by the Mantel-Cox statistic detected a statistically significant difference between the analyzed conditions (Log-Rank test, X2 = 11.2, df = 3, p = 0.0107 < 0.05). EN1 survived longer than SUP.5, other groups were similar to all. Conclusions: Thicker hybrid ceramic crows survived more than thin ceramic ones. http://dx.doi.org/10.1016/j.dental.2017.08.007
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C.B. André 1,∗ , J.L. Ferracane 2 , P.L. Rosalen 1 , C. Pfeifer 2 , B.M. Fronza 1 , L.C. Galvão 1 , M. Giannini 1 1
Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil 2 Oregon Health & Science University, Department of Biomaterials and Biomechanics, Portland, USA Purpose/aim: The objectives of this in vitro study were to evaluate the effect of the addition of two natural antimicrobial compounds derived from Brazilian propolis (Apigenin (A) and tt-Farnesol (T)) on the properties of resin composites (CO), resin cements (CE), and adhesives systems (Clearfil S3 Bond Plus – CS3; Optibond S – OPT); and on the virulence of Streptococcus mutans biofilm. Materials and methods: A and T were added separately or in combination into CS3, OPT, CO and CE; and combined with fluoride (F) into CO and CE. Dry weight (DW), bacterial viability (BV), alkali soluble (ASP) and intracellular (IPS) polysaccharides were determined from S. mutans biofilms grown for five days on resin composites and resin cements disks, and on adhesive-coated hydroxyapatite disks. The A or T addition effects were analyzed by flexural strength (FS) and flexural modulus (FM) of CO and CE, dentin bond strength (BS) of CS3 and OPT, immediately and after one year of water storage, curing kinetics (CK) and polymerization rate (PR). Results: The DW, IPS and ASP decreased when A, AT and ATF were added to CO and CE compared to the control group. DW decreased when A or AT were added to CS3 and when A or T were added to OPT. ASP decreased with the addition of A to CS3 and T to OPT. A or AT into CS3 decreased the IPS. No statistical difference was observed for BV, except when ATF was added to CE. No addition interfered with BS, FS and FM. OPT showed higher BS for both storage times. No BS reduction observed after one year of water storage for CS3. No difference was observed for CK and PR for either material tested. Conclusions: The addition of A and T to CO and CE significantly decrease the amount of DW and polysaccharides of S. mutans biofilm, which may impair the S. mutans virulence, without suppressing the target organism. The addition of A or AT to CS3 showed better results, comparing to OPT, regarding the reduction of virulence of S. mutans biofilm. http://dx.doi.org/10.1016/j.dental.2017.08.008
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Ultrafine ceramic restoration behavior under fatigue bonded in posterior teeth
Incorporating compounds in restorative materials that modify streptococcus mutans virulence
F.O. Abu-Izze ∗ , G.F. Ramos, L.C. Anami, M.A. Bottino São Paulo State University – UNESP, Brazil Purpose/aim: Restorations in thin thicknesses have been used as a form of minimally invasive clinical approach. The aim of this study was to compare hybrid and ceramic crowns according to the thickness of the posterior restoration under fatigue loading. Materials and methods: To evaluate the fatigue behavior of these restorations, 60 standard preparations were machined in G10 resin, and 60 partial table top restorations of different thicknesses (0.5 and 1.0 mm) were machined. After scanning a master preparation in the model and scanning the restoration waxing, they were machined by Cerec 3 CAD/CAM system (Cerec v3.03; Syrona Dental Systems GmbH, Bensheim, Germany) in ceramic-based lithium silicate reinforced by zirconia (SUP – Suprinity Vita) and polymer-infiltrated ceramic (EN – Enamic Vita); both, Vita Zahnfabrik, Bad Sackingen, Germany). From each material, 15 sets of G10 preparations and respective restorations with thickness 0.5 or 1.0 mm were obtained, generating the four groups: SUP.5, SUP1, EN.5, and EN1. After finishing and polishing, the restorations were cleaned in an ultrasonic bath with isopropyl alcohol for 10 min. SUP restorations were crystallized according to the manufacturer’s recommendations. The samples were then bonded to the G10 preparations using Panavia F 2.0 (Kuraray Noritake, Okayama, Japan). From the mean values of maximum load for compression fracture (n = 3), the parameters for stepwise stress fatigue test were determined. The test evaluated the fatigue strength (n = 12) of the restorations submitted to the load of 450 N during the mechanical cycles. By the number of mechanic cycles at 450 N required for the fracture of the specimens or considered the test suspended upon reaching 1,5 × 106 cycles. The presence of cracks and/or fractures was checked with interruption of the test and adequate light, and evaluated in a stereomicroscope every 5 × 105 cycles. The failure modes of all specimens were checked and representative samples were also evaluated in scanning electron microscopy. Results: The comparison between the experimental groups by the Mantel-Cox statistic detected a statistically significant difference between the analyzed conditions (Log-Rank test, X2 = 11.2, df = 3, p = 0.0107 < 0.05). EN1 survived longer than SUP.5, other groups were similar to all. Conclusions: Thicker hybrid ceramic crows survived more than thin ceramic ones. http://dx.doi.org/10.1016/j.dental.2017.08.007
e5
C.B. André 1,∗ , J.L. Ferracane 2 , P.L. Rosalen 1 , C. Pfeifer 2 , B.M. Fronza 1 , L.C. Galvão 1 , M. Giannini 1 1
Piracicaba Dental School, State University of Campinas, Piracicaba, Brazil 2 Oregon Health & Science University, Department of Biomaterials and Biomechanics, Portland, USA Purpose/aim: The objectives of this in vitro study were to evaluate the effect of the addition of two natural antimicrobial compounds derived from Brazilian propolis (Apigenin (A) and tt-Farnesol (T)) on the properties of resin composites (CO), resin cements (CE), and adhesives systems (Clearfil S3 Bond Plus – CS3; Optibond S – OPT); and on the virulence of Streptococcus mutans biofilm. Materials and methods: A and T were added separately or in combination into CS3, OPT, CO and CE; and combined with fluoride (F) into CO and CE. Dry weight (DW), bacterial viability (BV), alkali soluble (ASP) and intracellular (IPS) polysaccharides were determined from S. mutans biofilms grown for five days on resin composites and resin cements disks, and on adhesive-coated hydroxyapatite disks. The A or T addition effects were analyzed by flexural strength (FS) and flexural modulus (FM) of CO and CE, dentin bond strength (BS) of CS3 and OPT, immediately and after one year of water storage, curing kinetics (CK) and polymerization rate (PR). Results: The DW, IPS and ASP decreased when A, AT and ATF were added to CO and CE compared to the control group. DW decreased when A or AT were added to CS3 and when A or T were added to OPT. ASP decreased with the addition of A to CS3 and T to OPT. A or AT into CS3 decreased the IPS. No statistical difference was observed for BV, except when ATF was added to CE. No addition interfered with BS, FS and FM. OPT showed higher BS for both storage times. No BS reduction observed after one year of water storage for CS3. No difference was observed for CK and PR for either material tested. Conclusions: The addition of A and T to CO and CE significantly decrease the amount of DW and polysaccharides of S. mutans biofilm, which may impair the S. mutans virulence, without suppressing the target organism. The addition of A or AT to CS3 showed better results, comparing to OPT, regarding the reduction of virulence of S. mutans biofilm. http://dx.doi.org/10.1016/j.dental.2017.08.008