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BMC Oral Health Dec 2022In clinical settings, tooth preparation for prefabricated zirconia crowns (PZCs) in the primary dentition varies widely. However, knowledge about the biomechanical...
BACKGROUND
In clinical settings, tooth preparation for prefabricated zirconia crowns (PZCs) in the primary dentition varies widely. However, knowledge about the biomechanical behavior of PZCs in various clinical settings is limited. This study was conducted to evaluate the biomechanical behavior of PZCs in different clinical settings using 3-dimensional finite element analysis.
METHODS
3-dimensional models of the PZC, cement, and tooth with six different conditions were simulated in primary molar teeth, incorporating cement thickness (100, 500, and 1000 μm) and cement type (resin-modified glass ionomer cement and resin cement). A total of 200 N of occlusal force was applied to the models, both vertically and obliquely as representative cases. A general linear model univariate analysis with partial eta-squared (ηp) was performed to evaluate the relative effects of the variables.
RESULTS
The overall stress of tooth was increased as the cement space increases under oblique loading. The von Mises stress values of the resin cements were significantly higher than those of the resin-modified glass ionomer cements for all cement thicknesses (p < .05). The effect size of the cement type (η = .519) was more dominant than the cement thickness (η = .132) in the cement layer.
CONCLUSIONS
Within the limits of this study, cement type has a greater influence on the biomechanical behavior of PZCs than cement thickness.
Topics: Humans; Child; Finite Element Analysis; Tooth Preparation; Dental Cements; Glass Ionomer Cements; Dental Materials; Resin Cements; Crowns
PubMed: 36456927
DOI: 10.1186/s12903-022-02596-2 -
Brazilian Dental Journal 2023This study evaluated the effect of toothbrushing on enamel-cementing material-ceramic bonded interfaces, using different cementing materials.
UNLABELLED
This study evaluated the effect of toothbrushing on enamel-cementing material-ceramic bonded interfaces, using different cementing materials.
MATERIALS AND METHODS
Thirty enamel and thirty ceramic blocks were bonded with cementing materials to produce the samples that were bonded with three types of cementing materials: 1- RelyX Ultimate resin cement (REXU), 2- RelyX Unicem 2 self-adhesive resin cement (REU2) and 3- heated Z100 restorative composite (60°C). Bonded interfaces of the samples were toothbrushed and the surfaces of the 3 cementing materials were evaluated for roughness (RG, in µm), roughness profile (RP, in µm), and volume loss (VL, in µm3) (baseline and after 20,000 and 60,000 toothbrushing cycles). Data were evaluated by Generalized Linear Analysis (two factors: "material" and "toothbrushing cycle") and Bonferroni test (α=0.05).
RESULTS
REXU and Z100 exhibited lower RG than that presented by REU2, except after 60,000 toothbrushing cycles when only Z100 differed from REU2. The increase in toothbrushing cycles increased the RG and RP for all materials. REU2 also showed higher RP than those showed by REXU and Z100 when it was analyzed regarding the enamel. The VL of Z100 was the lowest with 20,000 toothbrushing cycles, regarding the enamel and ceramic. For 60,000 cycles, REXU showed the lowest VL regarding the ceramic, and REU2 had the highest VL regarding the enamel and ceramic.
CONCLUSION
In general, REXU and Z100 showed the best results regarding the evaluations performed and the REU2 exhibited the highest RG, RP, and VL.
Topics: Resin Cements; Toothbrushing; Dental Porcelain; Composite Resins; Dental Cements; Glass Ionomer Cements; Ceramics; Dental Enamel; Surface Properties; Materials Testing
PubMed: 38133474
DOI: 10.1590/0103-6440202305459 -
Journal of Indian Prosthodontic Society Apr 2024In routine dental care, various dental luting cements are utilized to cement the dental prosthesis. Thus, the aim of the current study was to assess the Cytotoxic effect...
AIM
In routine dental care, various dental luting cements are utilized to cement the dental prosthesis. Thus, the aim of the current study was to assess the Cytotoxic effect of three different dental luting cements on human gingival mesenchymal stem cell and evaluation of cytokines and growth factors release.
SETTINGS AND DESIGN
Cytotoxicity of glass ionomer cement (GIC), resin modified glass ionomer cement (RMGIC) and resin cement (RC) on the human gingival mesenchymal stem cells (HGMSCs) was evaluated. Amongst the cements tested, least cytotoxic cement was further tested for the release of cytokines and growth factors.
MATERIALS AND METHODS
MTT test was used to evaluate the cytotoxicity of the dental luting cements at 1 h, 24 h, and 48 h on HGMSCs. Cytokines such as interleukin (IL) 1α & IL 8 and growth factors such as platelet derived growth factor & transforming growth factor beta release from the least cytotoxic RC was evaluated using flow cytometry analysis.
STATISTICAL ANALYSIS USED
The mean absorbance values by MTT assay and cell viability at various time intervals between four groups were compared using a one way analysis of variance test and Tukey's post hoc test. The least cytotoxic RC group and the control group's mean levels of cytokines and growth factors were compared using the Mann-Whitney test.
RESULT
As exposure time increased, the dental luting cement examined in this study were cytotoxic. RC was the least cytotoxic, RMGIC was moderate and glass ionomer cement showed the highest cytotoxic effect. Concomitantly, a significant positive biological response of gingival mesenchymal stem cells with the release of ILs when exposed to the RC was observed.
CONCLUSION
For a fixed dental prosthesis to be clinically successful over the long term, it is imperative that the biocompatibility of the luting cement be taken into account in order to maintain a healthy periodontium surrounding the restoration.
Topics: Humans; Gingiva; Mesenchymal Stem Cells; Cytokines; Intercellular Signaling Peptides and Proteins; Dental Cements; In Vitro Techniques; Glass Ionomer Cements; Cell Survival; Cells, Cultured
PubMed: 38650340
DOI: 10.4103/jips.jips_260_23 -
Dental Materials : Official Publication... Jan 2019The addition of charged polymers, like poly-aspartic acid (pAsp), to mineralizing solutions allows for transport of calcium and phosphate ions into the lumen of collagen...
UNLABELLED
The addition of charged polymers, like poly-aspartic acid (pAsp), to mineralizing solutions allows for transport of calcium and phosphate ions into the lumen of collagen fibrils and subsequent crystallization of oriented apatite crystals by the so-called Polymer-Induced Liquid Precursor (PILP) mineralization process, leading to the functional recovery of artificial dentin lesions by intrafibrillar mineralization of collagen.
OBJECTIVE
To evaluate the feasibility of applying the PILP method as part of a restorative treatment and test for effectiveness to functionally remineralize artificial lesions in dentin.
MATERIALS AND METHODS
Two methods of providing pAsp to standardized artificial lesions during a restorative procedure were applied: (A) pAsp was mixed into commercial RMGI (resin modified glass ionomer) cement formulations and (B) pAsp was added at high concentration (25mg/ml) in solution to rehydrate lesions before restoring with a RMGI cement. All specimens were immersed in simulated body fluid for two weeks to allow for remineralization and then analyzed for dehydration shrinkage, integrity of cement-dentin interface, degree of mineralization, and changes in the nanomechanical profile (E-modulus) across the lesion.
RESULTS
After the remineralization treatment, lesion shrinkage was significantly reduced for all treatment groups compared to demineralized samples. Pores developed in RMGI when pAsp was added. A thin layer at the dentin-cement interface, rich in polymer formed possibly from a reaction between pAsp and the RMGI. When analyzed by SEM under vacuum, most lesions delaminated from the cement interface. EDS-analysis showed some but not full recovery of calcium and phosphorous levels for treatment groups that involved pAsp. Nanoindentations placed across the interface indicated improvement for RMGI containing 40% pAsp, and were significantly elevated when lesions were rehydrated with pAsp before being restored with RMGI. In particular the most demineralized outer zone recovered substantially in the elastic modulus, suggesting that functional remineralization has been initiated by pAsp delivery upon rehydration of air-dried demineralized dentin. In contrast, the effectiveness of the RMGI on functional remineralization of dentin was minimal when pAsp was absent.
SIGNIFICANCE
Incorporation of pAsp into restorative treatments using RMGIs promises to be a feasible way to induce the PILP-mineralization process in a clinical setting and to repair the structure and properties of dentin damaged by the caries process.
Topics: Apatites; Dental Caries; Dental Cements; Dentin; Glass Ionomer Cements; Humans
PubMed: 30545611
DOI: 10.1016/j.dental.2018.11.030 -
Brazilian Dental Journal 2022This study was aimed to evaluate the fit of occlusal veneer restoration for two CAD/CAM materials with different cement space settings, using microCT scans. Sixty resin...
This study was aimed to evaluate the fit of occlusal veneer restoration for two CAD/CAM materials with different cement space settings, using microCT scans. Sixty resin dies were made and divided into two groups (n=30) according to the materials, (I): Hybrid all-ceramic, and (II): zirconia-reinforced lithium silicate glass-ceramic. Each group was subdivided into three subgroups (n=10) according to the cement space parameters (30, 40, and 50 µm). Occlusal veneers for the six subgroups were milled. A circle with 20 different sections was placed at the center of every scanned specimen to measure four different locations (Occlusal, Axial, Marginal, and Absolute marginal discrepancy). Data were analyzed using two-way ANOVA at a 0.05 level of significance. There was no statistically significant effect of material type on the mean values of internal and marginal gaps for the three cement space parameters (P>0.05). There were no statistically significant differences in the occlusal and axial gap between the cement space parameters, furthermore, there were statistically significant differences in marginal gap distances and absolute marginal discrepancies (P>0.05). Hybrid all-ceramic showed smaller marginal and internal discrepancies than zirconia-reinforced lithium silicate glass-ceramic without statistically significant differences, and, for both materials, 50 µm cement space significantly improved the marginal fit and absolute marginal discrepancy.
Topics: Ceramics; Computer-Aided Design; Crowns; Dental Cements; Dental Marginal Adaptation; Dental Materials; Dental Porcelain; Dental Prosthesis Design; Glass Ionomer Cements; Lithium; Materials Testing; X-Ray Microtomography
PubMed: 36043571
DOI: 10.1590/0103-6440202204764 -
Dental Materials Journal Dec 2019The aim of this in vitro study was to explore light transmission through an individually formed fiber-reinforced composite (FRC) post compared with two prefabricated FRC...
The aim of this in vitro study was to explore light transmission through an individually formed fiber-reinforced composite (FRC) post compared with two prefabricated FRC posts. Three different glass FRC posts from different manufacturers were used: two groups included prefabricated glass FRC posts (RelyX and GC Fiber Posts) and one group consisted of individually formed E-glass FRC posts with semi-interpenetrating polymer network (semi-IPN) polymer matrix (everStick Post). Various lengths of posts and lightprotected cylinders were made. The specimens were light-polymerized on the test tray of a light radiance testing device (MARC Resin Calibrator). Light transmission in the direction of fibers was registered. Light transmission decreased with increasing post length (p≤0.001; ANOVA) up to 12 mm in all post groups. The individually formed FRC post showed highest light transmission in all cylinder lengths (p<0.001) compared to prefabricated FRC posts, which could benefit polymerization of post material and luting cement.
Topics: Composite Resins; Dental Cements; Dental Stress Analysis; Glass; Materials Testing; Post and Core Technique; Resin Cements
PubMed: 31406094
DOI: 10.4012/dmj.2018-217 -
Australian Dental Journal Mar 2022Fluoride has been shown to be an effective agent in the prevention of caries during orthodontic treatment. Resin-modified glass-ionomer cements possess therapeutic... (Review)
Review
Fluoride has been shown to be an effective agent in the prevention of caries during orthodontic treatment. Resin-modified glass-ionomer cements possess therapeutic anticariogenic properties acting as a fluoride reservoir and releasing fluoride into the environment, particularly at low pH where there is a threat of enamel demineralisation and white spot lesions (WSL's). Patient compliance to instructions in standard oral hygiene measures limits the success of caries prevention and the routine use of glass-ionomer cements can mitigate the lack of compliance, although RMGIC's are not a panacea against WSL's. The adhesion of GIC's to the enamel surface is a physicochemical bond rather than a mechanical bond which reduces the risk of iatrogenic damage to the enamel when bonding and debonding attachments. RMGIC's can be recommended as a bonding adhesive for all attachments but one needs to be selective when bonding molar attachments to avoid occlusal interferences as masticatory forces can be high in these areas.
Topics: Composite Resins; Dental Bonding; Dental Caries; Dental Cements; Fluorides; Glass Ionomer Cements; Humans; Orthodontic Brackets; Resin Cements
PubMed: 34762310
DOI: 10.1111/adj.12888 -
Indian Journal of Dental Research :... 2019The adhesives clinical effectiveness has been extensively reported for noncarious cervical lesions (NCCLs). However, there is a lack of information about the adhesive... (Randomized Controlled Trial)
Randomized Controlled Trial
CONTEXT
The adhesives clinical effectiveness has been extensively reported for noncarious cervical lesions (NCCLs). However, there is a lack of information about the adhesive systems strategies and their effect on NCCL restoration longevity.
AIMS
This study aims to evaluate a 42-month performance of four dentin adhesive systems used for the restorative treatment of NCCLs.
SETTINGS AND DESIGN
NCCLs were randomly divided into four groups: (1) Scotchbond multi-purpose (MP); 2: Single bond plus (SB); 3: Scotchbond SE (SE); and 4: Easy bond (EB).
SUBJECTS AND METHODS
NCCLs (125) were randomly distributed: (1) MP; (2) SB; (3) SE; and (4) EB and were restored with a nanofilled resin-composite, evaluated along 18-36-42 months.
STATISTICAL ANALYSIS USED
Kruskal-Wallis test: Comparison among the adhesive systems in each period. Friedman analysis: Comparison along the periods. Kaplan-Meier: Survival analysis.
RESULTS
Baseline and 42-month retention (RET) rates (%) were 100/100 for MP; 100/94.74 for SB; 100/87.5 for SE; and 100/100 for EB. The cumulative failure percentage was 9.52% for MP, 9.52% SB, 15.8% SE, and 10% EB. Restorations survival was not dependent on the used adhesive type. Marginal adaptation (MA) was similar to each group, but EB presented noticeable marginal deterioration. Wear was noticed in the 3-step etch-and-rinse (MP) restorations evaluated after 42 months. For the EB, baseline and 18-month wear evaluation were statistically similar. After 36 and 42 months, wear was also similar for EB.
CONCLUSIONS
Adhesive systems showed similar performance within most important adhesive bonding efficiency achievement parameters: RET, MA, interfacial staining, recurrent caries, and postoperative sensitivity evaluated during 42 months.
Topics: Composite Resins; Dental Bonding; Dental Caries; Dental Cements; Dental Marginal Adaptation; Dental Materials; Dental Restoration, Permanent; Dentin-Bonding Agents; Humans; Resin Cements
PubMed: 31745040
DOI: 10.4103/ijdr.IJDR_466_16 -
Journal of Applied Oral Science :... 2017This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC), water sorption (WS), and water solubility (WSB) of these bonding...
OBJECTIVE
This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC), water sorption (WS), and water solubility (WSB) of these bonding systems in an attempt to improve their physico-mechanical resistance.
MATERIAL AND METHODS
Two bonding agents were tested: a two-step total-etch system [Adper™ Single Bond 2, 3M ESPE (SB)] and a universal system [Adper™ Single Bond Universal, 3M ESPE (SU)]. Square-shaped specimens were prepared and assigned into 4 groups (n=5): SB and SU (control groups - no laser irradiation) and SB-L and SU-L [SB and SU laser (L) - irradiated groups]. DC was assessed using Fourier transform infrared spectroscopy with attenuated total reflectance. Additional uncured resin samples (≈3.0 µL, n=5) of each adhesive were also scanned for final DC calculation. For WS/WSB tests, similar specimens (n=10) were prepared and measured by monitoring the mass changes after dehydration/water storage cycles. For both tests, adhesive fluids were dropped into standardized Teflon molds (6.0×6.0×1.0 mm), irradiated with a 970-nm laser diode, and then polymerized with an LED-curing unit (1 W/cm2).
RESULTS
Laser irradiation immediately before photopolymerization increased the DC (%) of the tested adhesives: SB-L>SB>SU-L>SU. For WS/WSB (μg/mm3), only the dentin bonding system (DBS) was a significant factor (p<0.05): SB>SU.
CONCLUSION
Irradiation with a laser diode improved the degree of conversion of all tested simplified dentin bonding systems, with no impact on water sorption and solubility.
Topics: Curing Lights, Dental; Dental Cements; Dentin-Bonding Agents; Lasers, Semiconductor; Light-Curing of Dental Adhesives; Phase Transition; Photochemical Processes; Polymerization; Reference Values; Reproducibility of Results; Solubility; Spectroscopy, Fourier Transform Infrared; Statistics, Nonparametric; Surface Properties
PubMed: 28877276
DOI: 10.1590/1678-7757-2016-0461 -
Brazilian Dental Journal 2022The aim of this study was to investigate the physicochemical and biological properties of an experimental tricalcium silicate-based repair cement containing diclofenac...
The aim of this study was to investigate the physicochemical and biological properties of an experimental tricalcium silicate-based repair cement containing diclofenac sodium (CERD). For the physicochemical test, MTA, Biodentine and CERD were mixed and cement disc were prepared to evaluate the setting time and radiopacity. Root-end cavity were performed in acrylic teeth and filled with cements to analyze the solubility up to 7 days. Polyethylene tubes containing cements were prepared and calcium ions and pH were measured at 3h, 24h, 72h and 15 days. For the biological test, SAOS-2 were cultivated, exposed to cements extracts and cell proliferation were investigated by MTT assay at 6h, 24h and 48h. Polyethylene tubes containing cements were implanted into Wistar rats. After 7 and 30 days, the tubes were removed and processed for histological analyses. Parametric and nonparametric data were performed. No difference was identified in relation to setting time, radiopacity and solubility. Biodentine released more calcium ion than MTA and CERD; however, no difference between MTA and CERD were detected. Alkaline pH was observed for all cements and Biodentine exhibited highest pH. All cements promoted a raise on cell proliferation at 24h and 48h, except CERD at 48h. Biodentine stimulated cell metabolism in relation to MTA and CERD while CERD was more cytotoxic than MTA at 48h. Besides, no difference on both inflammatory response and mineralization ability for all cement were found. CERD demonstrated similar proprieties to others endodontic cements available.
Topics: Animals; Rats; Aluminum Compounds; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Calcium; Calcium Compounds; Dental Cements; Drug Combinations; Glass Ionomer Cements; Materials Testing; Oxides; Polyethylenes; Rats, Wistar; Root Canal Filling Materials; Silicates
PubMed: 35766716
DOI: 10.1590/0103-6440202204644