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The Journal of Contemporary Dental... Dec 2022The purpose of this study is to compare and evaluate the influence of two different cement space settings and two different cement types on the stress distribution under...
Influence of Different Cements and Cement Thickness on the Stress Distribution under Occlusal Surfaces of Porcelain-fused-to-metal and Porcelain-fused-to-zirconium Crowns: A Finite Element Analysis.
AIM
The purpose of this study is to compare and evaluate the influence of two different cement space settings and two different cement types on the stress distribution under occlusal surfaces of tooth restored with two different types of crowns and studied by using three-dimensional (3D) finite element analysis (FEA).
MATERIALS AND METHODS
Eight 3D finite element models (FEMs) representing a mandibular first molar tooth restored with crowns of, porcelain-fused-to-metal (PFM) and porcelain-fused-to-zirconia (PFZ) crowns with two cement space settings (50 and 80 µm) and with two different types of cement were constructed, using an FEA software (ANSYS, version 10). Each model was subjected to a distributed load simulating normal masticatory bite force of 225 N and was applied axial direction. Also, von Mises stress of each individual part in the system of models was calculated.
RESULTS
The PFM crowns undergo less stress distribution than the PFZ crowns. The PFM crowns are more compatible with self-adhesive cements, and the PFZ crowns are more compatible with resin-modified glass ionomer cements.
CONCLUSION
The PFM crowns with G-Cem Link Ace with 50 µm and PFZ crowns with RelyX Luting Plus with 80 µm combinations displayed less amount of stress distribution under normal masticatory bite force.
CLINICAL SIGNIFICANCE
Self-adhesive resin cements with PFM crowns and PFZ with resin-modified glass ionomer cements show more benefits in stress distribution under occlusal surfaces under normal masticatory bite force.
Topics: Dental Porcelain; Resin Cements; Finite Element Analysis; Zirconium; Dental Cements; Crowns; Glass Ionomer Cements; Materials Testing; Dental Stress Analysis
PubMed: 37125520
DOI: 10.5005/jp-journals-10024-3448 -
Journal of Prosthodontics : Official... Jan 2019To evaluate the effect of temporary cement cleaning methods on the retention of cemented crowns using zinc phosphate cement and resin-modified glass ionomer cement.
PURPOSE
To evaluate the effect of temporary cement cleaning methods on the retention of cemented crowns using zinc phosphate cement and resin-modified glass ionomer cement.
MATERIALS AND METHODS
Forty titanium specimens were fabricated to simulate prepared molars with minimally retentive taper. The Ni-Cr cast crowns were fabricated, temporarily cemented, and separated. The specimens were divided into four groups according to the temporary cement cleaning method (n = 10) as follows: control group (no temporary cementation), orange solvent group, ultrasonic cleaning group, and air-abrasion group. After the cleaning procedures, the specimens were cemented with definitive cements (zinc phosphate cement and resin-modified glass ionomer, RMGI, cement) and subjected to thermocycling (5000 cycles, 5-55°C, dwell time, 10 seconds). The tensile bond strength of each specimen was measured using a universal testing machine, and the results were analyzed using the Kruskal-Wallis and Mann-Whitney U test (α = 0.05).
RESULTS
When cemented with zinc phosphate cement, the statistical analysis showed that the value of the air-abrasion group was significantly higher than those of the other groups (p < 0.01). There was no statistically significant difference among the other groups. When cemented with RMGI cement, the air-abrasion group showed the lowest value, and the control group showed the highest value (p < 0.01). The difference between the ultrasonic cleaning group and the orange solvent group was not statistically significant.
CONCLUSION
The use of temporary cement did not have a significant influence on retention of permanently cemented crowns when zinc phosphate cement was used for permanent cementation. Airborne-particle abrasion after provisional cementation improved retention of crowns cemented with zinc phosphate cement; however, the use of temporary cement significantly decreased retention of permanently cemented crowns when RMGI cement was used regardless of the temporary cement cleaning method.
Topics: Air Abrasion, Dental; Cementation; Crowns; Dental Cements; Dental Materials; Dental Prosthesis Retention; Dental Stress Analysis; Detergents; Glass Ionomer Cements; Humans; Materials Testing; Tensile Strength; Ultrasonic Therapy; Zinc Phosphate Cement
PubMed: 28598530
DOI: 10.1111/jopr.12646 -
The International Journal of Esthetic... Feb 2023The fracture strength of implant-supported monolithic CAD/CAM crowns under approximate clinical conditions and how their fracture strength is affected by cement type...
The fracture strength of implant-supported monolithic CAD/CAM crowns under approximate clinical conditions and how their fracture strength is affected by cement type remain unclear. The present study investigated the fracture resistance of implant-supported polymer-infiltrated ceramic and zirconia-reinforced lithium silicate glass-ceramic crowns cemented with two different cement types after aging in a mastication simulator. RelyX Ultimate Clicker (3M ESPE) as adhesive resin cement, Panavia SA Cement Plus (Kuraray Noritake) as self-adhesive resin cement, and two monolithic materials (A1-T for Enamic and M1-HT for Suprinity; both Vita Zahnfabrik) were tested. Forty CAD/CAM-produced monolithic implant-supported crowns for a maxillary right second premolar were prepared, and crowns were cemented to the straight implant abutments with each cement, then subjected to dynamic load cycling (480,000 cycles) and thermocycling (about 4,000 cycles) in a mastication simulator. Crown fracture resistance was analyzed by the load-to-failure test. Crown-abutment samples were loaded until fracture. No significant difference was observed in the fracture load of the crowns among the groups. The results suggest that both monolithic restoration materials could be an alternative for implant-supported cement-retained restorations, regardless of cement type.
Topics: Humans; Dental Porcelain; Resin Cements; Flexural Strength; Mastication; Materials Testing; Ceramics; Crowns; Dental Cements; Glass Ionomer Cements; Zirconium; Computer-Aided Design; Dental Stress Analysis; Dental Restoration Failure
PubMed: 36734424
DOI: No ID Found -
The cytotoxic and oxidative effects of restorative materials in cultured human gingival fibroblasts.Drug and Chemical Toxicology Sep 2021The aim of this study was to evaluate the cytotoxic and oxidative effects of the most commonly used dental restorative materials on human gingival fibroblast cells... (Comparative Study)
Comparative Study
The aim of this study was to evaluate the cytotoxic and oxidative effects of the most commonly used dental restorative materials on human gingival fibroblast cells (HGFCs). HGFCs were obtained from healthy individuals. The tested restorative materials were a microhybrid resin based composite, a compomer resin, a glass ionomer cement, and an amalgam alloy. One hundred eight cylindirical samples, 10 mm in diameter and 2 mm in height, were prepared according to ISO 10993-12:2002 specifications ( = 9 in the tested subgroups). Freshly prepared and aged samples in artificial saliva at 37 °C (7 and 21 d) were placed into well plates and incubated. Wells without dental materials were constituted as the control group. After 72 h incubation period, cytotoxicity was determined using the neutral red (NR) assay. Oxidative alterations were assessed using total antioxidant capacity (TAC) and total oxidant status (TOS) assay kits. Data were analyzed using the ANOVA and LSD post hoc tests. All tested materials led to significant decreases in the cell viability rates (33-73%) compared to the control group. Glass ionomer and resin composite were found to be more cytotoxic than amalgam alloy and compomer. The highest TAC level was observed in glass ionomer after seven-day aging and these changes prevented an increase in TOS levels. Increases in TAC levels after seven-day aging in all groups exhibited significant differences with freshly prepared samples ( < 0.05). In all material groups, TOS levels of freshly prepared samples differed statistically and significantly from samples aged for 7 and 21 d ( < 0.05). The data obtained suggested that all the tested materials exhibited cytotoxic and pro-oxidant features. Freshly prepared samples caused higher TOS levels. However, oxidant status induced by materials decreased over time.
Topics: Cells, Cultured; Compomers; Composite Resins; Dental Alloys; Dental Amalgam; Dental Cements; Fibroblasts; Gingiva; Glass Ionomer Cements; Humans; Materials Testing; Oxidative Stress; Saliva; Time Factors
PubMed: 31146597
DOI: 10.1080/01480545.2019.1620265 -
Indian Journal of Dental Research :... 2020In-vitro studies of microleakage are an initial screening method to assess the maximum theoretical loss of sealing ability in-vivo.
CONTEXT
In-vitro studies of microleakage are an initial screening method to assess the maximum theoretical loss of sealing ability in-vivo.
AIMS
Our objective was to determine and compare microleakage patterns of conventional glass ionomer cement (GIC) and resin-modified GIC (RMGIC) for band cementation.
METHODS
Forty caries-free second primary molars were randomly divided into two groups of 20 teeth each. Preformed molar bands in the two groups were cemented to enamel with one of two types of cement: Conventional GIC (Fuji I, GC Corporation; Tokyo, Japan) and RMGIC (Fuji Plus, GC Corporation; Tokyo, Japan). A dye penetration method was used for microleakage evaluation. Microleakage was determined by a stereomicroscope for the cement-band and cement-enamel interfaces.
STATISTICAL ANALYSIS USED
Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests.
RESULTS
The mean microleakage value for conventional GIC (Fuji I) at cement-band and cement-enamel interfaces was 2.41 mm and 2.15 mm, respectively. The mean microleakage value for RMGIC (Fuji Plus) at cement-band and cement-enamel interfaces was 0.44 mm and 0.46 mm, respectively. Compared to conventional GIC, RMGIC showed less microleakage at both cement-band and cement-enamel interfaces. P < 0.001 and it was statistically highly significant.
CONCLUSIONS
Bands cemented with RMGIC had significantly less microleakage between the cement-band and cement-enamel interfaces than conventional GIC.
Topics: Dental Cements; Dental Enamel; Dental Leakage; Glass Ionomer Cements; Humans; Resin Cements; Tooth, Deciduous
PubMed: 32436911
DOI: 10.4103/ijdr.IJDR_850_19 -
BMC Oral Health Dec 2022Adhesive tooth-colored restorations are strongly dependent on the substrate surface cleanliness to allow intimate contact between resin cement and dentin surface, so...
BACKGROUND
Adhesive tooth-colored restorations are strongly dependent on the substrate surface cleanliness to allow intimate contact between resin cement and dentin surface, so several methods were adopted for the total cleaning of temporary cement residues. This study aimed to assess the effect of mechanical and chemo-mechanical cleaning methods of temporary cement on the immediate shear bond strength of self-adhesive resin cement to dentin surface.
METHODS
Forty freshly extracted lower first premolars were cut to expose a flat dentin surface. Discs of temporary crown composite resin material were constructed and cemented to the flat dentin surface using resin-based and non-eugenol temporary cement then stored at room temperature in distilled water. Dividing of samples into two groups according to the method of temporary cement cleaning. Group I (n = 20) mechanical cleaning using the rotary instrument, and group II (n = 20) chemo-mechanical cleaning using chlorhexidine-containing scrub. CAD/CAM reinforced Composite discs were bonded to the dentin surface using self-adhesive composite resin cement, then measurement of shear bond strength was done using a universal testing machine. Further analysis of failure mode after debonding was performed by Scanning electron microscope.
RESULTS
No statistically significant difference was found between the mean shear bond strength of the two cleaning methods (P-value = 0.636). Regardless of the cleaning method, the group cemented with resin-based temporary cement showed statistically significantly higher mean shear bond strength than non-eugenol temporary cement (P-value = 0.048).
CONCLUSION
Both cleaning methods (mechanical and chemo-mechanical) applied in this study were effective in cleaning temporary cement remnants from the dentin substrate surface with statistically significant differences between results of shear bond strength with significantly higher values recorded with resin-based temporary cement.
Topics: Humans; Dental Cements; Resin Cements; Zinc Oxide-Eugenol Cement; Dentin-Bonding Agents; Dental Bonding; Glass Ionomer Cements; Composite Resins; Dentin; Materials Testing; Shear Strength; Surface Properties; Dental Stress Analysis
PubMed: 36578003
DOI: 10.1186/s12903-022-02672-7 -
The Journal of Contemporary Dental... Oct 2022To compare the surface microhardness, compressive strength, and antimicrobial activity of white Portland nanoparticle and microparticle Peruvian cement, mineral trioxide...
Comparative Evaluation of Physicomechanical Properties and Antimicrobial Activity of White Portland Micro- and Nanoparticulate Peruvian Cement, Mineral Trioxide Aggregate, and Neomineral Trioxide Aggregate.
AIM
To compare the surface microhardness, compressive strength, and antimicrobial activity of white Portland nanoparticle and microparticle Peruvian cement, mineral trioxide aggregate (MTA), and neomineral trioxide aggregate (NeoMTA) at 24 hours and 28 days.
MATERIALS AND METHODS
Twenty specimens were prepared for each group of cement microparticulated powder (PCm), nanoparticulated cement (PCn), MTA, and NeoMTA to be evaluated at two different times, 24 hours and 28 days for the surface microhardness test and compressive strength. For the antimicrobial activity tests, another 20 specimens were prepared for each group of cement where they were subdivided into two subgroups according to the different periods at 24 hours and 48 hours. For the surface microhardness and compressive strength, the specimens, and the cement groups were mixed according to the manufacturer's instructions and transferred to a cylindrical polyethylene mold of 6-mm diameter and 4-mm height. The compressive strength test was conducted using a universal testing machine. Moreover, the agar diffusion technique was to evaluate the antibacterial and antifungal activity of the American Type Culture Collection (ATCC) and . Finally, the data were statistically analyzed.
RESULTS
The highest microhardness values for the 24-hour subgroup were recorded for NeoMTA cement (16.99 ± 2.02), followed by MTA, PCn, and PCm, respectively. As for the 28-day subgroup, PCn cement (41.64 ± 3.20) presented the highest microhardness, followed by NeoMTA, PCm, and MTA, respectively, with statistically significant differences among them. The compressive strength of both subgroups 24 hours and 28 days exhibited the highest mean for PCn (41.3 ± 4.29, 65.74 ± 3.06), followed by PCm, NeoMTA, and the lowest value for MTA cement. Finally, for the antimicrobial activity, the highest mean for the 24-hours and 48-hours subgroup was recorded for NeoMTA cement (17.6 ± 1.26, 17.8 ± 1.44), followed by PCn, PCm, and the lowest value for MTA, with significant differences between them.
CLINICAL SIGNIFICANCE
It is highly recommended, Portland cement (PC) as a viable substitute since it has very similar components and properties, but at a lower cost.
CONCLUSION
Regardless of the evaluation time, PCn produced higher surface microhardness and compressive strength; however, NeoMTA showed higher antimicrobial activity.
Topics: Peru; Root Canal Filling Materials; Calcium Compounds; Oxides; Silicates; Aluminum Compounds; Dental Cements; Drug Combinations; Glass Ionomer Cements; Anti-Bacterial Agents
PubMed: 37073907
DOI: 10.5005/jp-journals-10024-3421 -
Medical Science Monitor Basic Research Nov 2022BACKGROUND The aim of this study was to evaluate the antimicrobial effectiveness of dental cement materials for the prevention of bacterial growth, which can cause...
BACKGROUND The aim of this study was to evaluate the antimicrobial effectiveness of dental cement materials for the prevention of bacterial growth, which can cause failure of fixed cementation. MATERIAL AND METHODS We developed an agar diffusion disk test in-house to evaluate the antibacterial properties of 3 commercially available dental cement materials (Ketac, Harvard FLB, and Panavia SA Universal Dual Resin cements) compared with a negative control. The materials were tested for the inhibition against Streptococcus mutans (ATCC 10449), Streptoccocus salivarius (ATCC 25975), Enterococcus faecalis (ATCC 29212), and Lactobacilus acidophilus (ATCC 4356). The antimicrobial effectiveness of materials was expressed as the diameters of the inhibition zones around the disk. RESULTS Overall, 240 specimens were tested. All cement materials showed antimicrobial effectiveness. Different microbial strains reacted differently to the different dental cements (all P.
Topics: Anti-Infective Agents; Anti-Bacterial Agents; Streptococcus mutans; Resin Cements
PubMed: 36394828
DOI: 10.12659/MSMBR.937893 -
Dental Materials Journal Feb 2019The objectives were to develop a novel rechargeable cement containing amorphous calcium-phosphate nanoparticles (nanoACP) to suppress tooth decay. Five cements were made...
The objectives were to develop a novel rechargeable cement containing amorphous calcium-phosphate nanoparticles (nanoACP) to suppress tooth decay. Five cements were made with: (1) 60% glass particles (experimental control); (2) 40% glass+20% nanoACP; (3) 30% glass+30% nanoACP; (4) 20% glass+40% nanoACP; (5) 10% glass+50% nanoACP. Groups 1-4 had enamel bond strengths similar to Transbond XT (3M) and Vitremer (3M) (p>0.1). The nanoACP cement had calcium and phosphate ion release which increased with increasing nanoACP fillers. The recharged cement had substantial ion re-release continuously for 14 days after a single recharge. Ion re-release did not decrease with increasing recharge/re-release cycles. Groups 3-5 maintained a safe pH of medium (>5.5); however, control cements had cariogenic pH of medium (<4.5) due to biofilm acid. Therefore, nanoACP cement (1) had good bond strength to enamel, (2) possessed calcium and phosphate ion recharge/re-release capability, and (3) raised biofilm pH to a safe level to inhibit caries.
Topics: Biofilms; Calcium Phosphates; Composite Resins; Dental Caries; Dental Cements; Glass; Glass Ionomer Cements; Hydrogen-Ion Concentration; Ions; Materials Testing; Nanoparticles; Resin Cements; Shear Strength; Tooth Remineralization
PubMed: 30504692
DOI: 10.4012/dmj.2017-420 -
Quintessence International (Berlin,... Feb 2024To compare marginal gap width and depth with different cementation systems, excess removal, and after polishing.
OBJECTIVES
To compare marginal gap width and depth with different cementation systems, excess removal, and after polishing.
METHOD AND MATERIALS
In total, 80 composite crowns were milled, divided into ten groups, and cemented on identical artificial teeth. Eight crowns per group were fixed with (i) zinc phosphate cement (ZnOPh), (ii) glass-ionomer cement (GIC), (iii) resin-reinforced glass-ionomer cement (GIC mod), (iv) dual-curing adhesive composite (Comp dual), or (v) dual-curing self-adhesive composite (Comp SE dual). Excess removal was performed with a scaler after brief light-cure (tack-cure), final light-cure, during rubber or gel phase or by wiping with foam pellet. Curing was completed in chemical, dark cure, or light-curing modus. The specimens were polished and stored in water (37°C). The margins were digitized using a 3D laser-scanning microscope (VK-X100 series, Keyence). The width and the depth of the marginal gap were measured at 10 points between the crown margin and the preparation margin.
RESULTS
The width after excess removal varied between 65.1 ± 15.7 µm (Comp dual, wipe, with polishing) and 208.6 ± 266.7 µm (Comp SE dual, dark cure, without polishing). The depth varied between 29.8 ± 22.2 µm (Comp dual, wipe, with polishing) and 89.5 ± 45.2 µm (Comp SE dual, dark cure, without polishing). The impact on gap width and depth was detected for fixation material, excess removal, and polishing.
CONCLUSION
The gap depth and width depend on the luting material and the mode of access removal. Polishing can improve the gap quality, especially for GIC and resin-based systems.
Topics: Humans; Resin Cements; Surface Properties; Dental Cements; Glass Ionomer Cements; Cementation; Crowns; Materials Testing; Composite Resins
PubMed: 38108419
DOI: 10.3290/j.qi.b4780239