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Dental Materials : Official Publication... Jul 2023To evaluate the reliability, maximum principal stress, shear stress, and crack initiation of a computer-aided design/computer-aided manufacturing (CAD/CAM) resin...
OBJECTIVE
To evaluate the reliability, maximum principal stress, shear stress, and crack initiation of a computer-aided design/computer-aided manufacturing (CAD/CAM) resin composite (RC) incorporating surface pre-reacted glass (S-PRG) filler for primary molar teeth.
METHODS
Mandibular primary molar crowns fabricated by experimental (EB) or commercially available CAD/CAM RCs (HC) were prepared and cemented to a resinous abutment tooth using an adhesive resin cement (Cem) or a conventional glass-ionomer cement (CX). These specimens were subjected to a single compressive test (n = 5/each) and the step-stress accelerated life testing (SSALT) (n = 12/each). Data was evaluated using Weibull analyses and reliability was calculated. Afterwards, the maximum principal stress and crack initiation point of each crown was analyzed by finite element analysis. To evaluate bonding of EB and HC to dentin, microtensile bond strength (μTBS) testing was conducted using primary molar teeth (n = 10/each).
RESULTS
There was no significant difference between the fracture loads of EB and HC for either cement (p > 0.05). The fracture loads of EB-CX and HC-CX were significantly lower than EB-Cem and HC-Cem (p < 0.05). The reliability at 600 N for EB-Cem was greater than that for EB-CX, HC-Cem, and HC-CX. The maximum principal stress concentrated on EB was lower than that on HC. The shear stress concentrated in the cement layer for EB-CX was higher than that for HC-CX. There was no significant difference among the μTBSs of EB-Cem, EB-CX, HC-Cem, and HC-CX (p > 0.05).
SIGNIFICANCE
The crowns fabricated with the experimental CAD/CAM RC incorporating S-PRG filler yielded greater fracture loads and reliability than the crowns manufactured with commercially available CAD/CAM RC regardless of the luting materials. These findings suggest that the experimental CAD/CAM RC crown may be clinically useful for the restoration of primary molars.
Topics: Reproducibility of Results; Crowns; Dental Cements; Resin Cements; Glass Ionomer Cements; Molar; Composite Resins; Computer-Aided Design; Materials Testing; Dental Stress Analysis
PubMed: 37208292
DOI: 10.1016/j.dental.2023.04.006 -
Heliyon Jan 2024One of the main challenges facing dental implant success is peri-implantitis. Recent evidence indicates that titanium (Ti) corrosion products and undetected-residual...
STATEMENT OF PROBLEM
One of the main challenges facing dental implant success is peri-implantitis. Recent evidence indicates that titanium (Ti) corrosion products and undetected-residual cement are potential risk factors for peri-implantitis. The literature on the impact of various types of dental cement on Ti corrosion is very limited.
PURPOSE
This study aimed to determine the influence of dental cement on Ti corrosion as a function of cement amount and type.
MATERIALS AND METHODS
Thirty commercially pure Ti grade 4 discs (19 × 7mm) were polished to mirror-shine (Ra ≈ 40 nm). Samples were divided into 10 groups (n = 3) as a cement type and amount function. The groups were no-cement as control, TempBond NE (TB3mm, TB5mm, and TB8mm), FujiCEM-II (FC3mm, FC5mm, and FC8mm), and Panavia-F-2.0 (PC3mm, PC5mm, and PC8mm). Tafel's method estimated corrosion rate () and corresponding potential (E) from potentiodynamic curves. Electrochemical Impedance Spectroscopy (EIS) data was utilized to obtain Nyquist and Bode plots. An equivalent electrical circuit estimated polarization resistance (R) and double-layer capacitance (C). Inductively coupled plasma mass spectrometry (ICP-MS) analysis was conducted to analyze the electrolyte solution after corrosion. pH measurements of the electrolyte were recorded before and after corrosion tests. Finally, the corroded surface was characterized by a 3D white-light microscope and scanning electron microscope. Statistical analysis was conducted using either one-way ANOVA followed by Tukey's Post Hoc test or Kruskal-Wallis followed by Dunn's test based on data distribution.
RESULTS
Based on cement amount, FC and PC significantly increased in higher amounts (FC8mm- = 8.22 × 10A/cm, PC8mm- = 5.61 × 10A/cm) compared to control (3.35 × 10A/cm). In contrast, TB3mm decreased significantly compared to the control. As a function of cement type, FC increased the most. EIS data agrees with these observations. Finally, corroded surfaces had higher surface roughness (Ra) compared to non-corroded surfaces.
CONCLUSION
The study indicated that cement types FC and PC led to increased Ti-corrosion as a function of a higher amount. Hence, the implant stability could be impacted by the selection, excessive cement, and a potentially increased risk of peri-implantitis.
PubMed: 38192807
DOI: 10.1016/j.heliyon.2023.e23626 -
Clinical and Experimental Dental... Dec 2023The aim of this study was to review the selection criteria of resin cements for different types of partial coverage restorations (PCRs) and investigate if the type of... (Review)
Review
OBJECTIVE
The aim of this study was to review the selection criteria of resin cements for different types of partial coverage restorations (PCRs) and investigate if the type of restorations or restorative materials affect the type of selected resin cement.
MATERIALS AND METHODS
An electronic search (1991-2023) was performed in PubMed, Medline, Scopus, and Google Scholar databases by combinations of related keywords.
RESULTS
A total of 68 articles were included to review the selection criteria based on the advantages, disadvantages, indications, and performance of resin cements for different types of PCRs.
CONCLUSIONS
The survival and success of PCRs are largely affected by appropriate cement selection. Self-curing and dual-curing resin cements have been recommended for the cementation of metallic PCRs. The PCRs fabricated from thin, translucent, and low-strength ceramics could be adhesively bonded by light-cure conventional resin cements. Self-etching and self-adhesive cements, especially dual-cure types, are not generally indicated for laminate veneers.
Topics: Resin Cements; Ceramics; Dental Cements; Cementation
PubMed: 37427500
DOI: 10.1002/cre2.761 -
Journal of Functional Biomaterials May 2024There is a vast amount of published literature concerning dental veneers; however, the effects of tooth preparation, aging, veneer type, and resin cement type on the... (Review)
Review
There is a vast amount of published literature concerning dental veneers; however, the effects of tooth preparation, aging, veneer type, and resin cement type on the failure of dental veneers in laboratory versus clinical scenarios are not clear. The purpose of the present narrative review was to determine the principal factors associated with failures of dental veneers in laboratory tests and to understand how these factors translate into clinical successes/failures. Articles were identified and screened by the lead author in January 2024 using the keywords ''dental veneer", "complication", "survival rate", "failure", and "success rate" using PubMed/Medline, Scopus, Google Scholar, and Science Direct. The inclusion criteria included articles published between January 1999 and January 2024 on the topics of preparation of a tooth, aging processes of the resin cement and veneer, translucency, thickness, fabrication technique of the veneer; shade, and thickness of the resin cement. The exclusion criteria included articles that discussed marginal and internal fit, microhardness, water sorption, solubility, polishability, occlusal veneers, retention, surface treatments, and wear. The results of the present review indicated that dental veneers generally have a high survival rate (>90% for more than 10 years). The amount of preserved enamel layer plays a paramount role in the survival and success rates of veneers, and glass-ceramic veneers with minimal/no preparation showed the highest survival rates. Fracture was the primary failure mechanism associated with decreased survival rate, followed by debonding and color change. Fractures increased in the presence of parafunctional activities. Fewer endodontic complications were associated with veneer restorations. No difference was observed between the maxillary and mandibular teeth. Fractures can be reduced by evaluation of occlusion immediately after cementation and through the use of high-strength veneer materials, resin cements with low moduli, and thin layers of highly polished veneers. Debonding failures can be reduced with minimal/no preparation, and immediate dentin sealing should be considered when dentin is exposed. Debonding can also be reduced by preventing contamination from blood, saliva, handpiece oil, or fluoride-containing polishing paste; through proper surface treatment (20 s of hydrofluoric acid etching for glass ceramic followed by silane for 60 s); and through use of light-cured polymerization for thin veneers. Long-term color stability may be maintained using resin cements with UDMA-based resin, glass ceramic materials, and light-cure polymerization with thin veneers.
PubMed: 38786642
DOI: 10.3390/jfb15050131 -
International Journal of Clinical... Aug 2023To evaluate the effect of different add-ons on the flexural strength (FS) of glass ionomer cement (GIC).
AIM
To evaluate the effect of different add-ons on the flexural strength (FS) of glass ionomer cement (GIC).
MATERIALS AND METHODS
Around 72 samples were fabricated and divided among the following six different groups: group I-control (conventional GIC-nonmodified), group II-GIC powder modified with 3% titanium dioxide (TiO) and liquid is unmodified, group III-powder modified with 10% nanohydroxyapatite (nHA) and liquid is unmodified, group IV-powder is unmodified and Liquid is modified with 10% chitosan (CH), group V-powder is modified with 3% TiO and liquid is modified with 10% CH, and group VI-powder is modified with 10% nHA and liquid is modified with 10% CH. The samples were then subjected to a three-point bending test on a universal testing machine for the evaluation of FS. The results obtained were analyzed statistically using the analysis of variance (ANOVA) test.
RESULT
The mean FS value of group V depicts significantly high FS among all groups (29.42 ± 3.35). A significant difference was present in FS amongst all the groups that is groups V>II>IV>VI>III>I.
CONCLUSION
Glass ionomer cement (GIC) powder can be modified with nHA, nanotitanium, and GIC liquid can be modified with CH to improve its FS.
CLINICAL SIGNIFICANCE
Glass ionomer cement (GIC) supplemented with additives like nanoparticles (NPs) and CH can be used as an enhanced filling material due to its potential antibacterial properties and in areas with a high masticatory load.
HOW TO CITE THIS ARTICLE
Showkat I, Chaudhary S, Sinha AA, Comparative Evaluation of Flexural Strength of Conventional Glass Ionomer Cement and Glass Ionomer Cement Modified with Chitosan, Titanium Dioxide Nanopowder and Nanohydroxyapatite: An Study. Int J Clin Pediatr Dent 2023;16(S-1):S72-S76.
PubMed: 37663222
DOI: 10.5005/jp-journals-10005-2617 -
Dental Materials : Official Publication... Apr 2024Although the introduction of self-adhesive composites in restorative dentistry is very promising, the innovation of new materials also presents challenges and unknowns....
OBJECTIVES
Although the introduction of self-adhesive composites in restorative dentistry is very promising, the innovation of new materials also presents challenges and unknowns. Therefore, the aim of this study was to investigate the cytotoxicity of four different self-adhesive composites (SAC) in vitro and to compare them with resin-modified glass ionomer cements (RM-GIC), a more established group of materials.
METHODS
Samples of the following materials were prepared according to ISO 7405/10993-12 and eluted in cell culture medium for 24 h at 37 °C: Vertise Flow, Fusio Liquid Dentin, Constic, Surefil One, Photac Fil and Fuji II LC. Primary human pulp cells were obtained from extracted wisdom teeth and cultured for 24 h with the extracts in serial dilutions. Cell viability was evaluated by MTT assay, membrane disruption was quantified by LDH assay and apoptosis was assessed by flow cytometry after annexin/PI staining.
RESULTS
Two SAC (Constic and Vertise Flow) and one RM-GIC (Photac Fil) significantly reduced cell viability by more than 30% compared to the untreated control (p < 0.001). Disruptive cell morphological changes were observed and the cells showed signs of late apoptosis and necrosis in flow cytometry. Membrane disruption was not observed with any of the investigated materials.
CONCLUSION
Toxic effects occurred independently of the substance group and need to be considered in the development of materials with regard to clinical implications.
CLINICAL SIGNIFICANCE
SAC have many beneficial qualities, however, the cytotoxic effects of certain products should be considered when applied in close proximity to the dental pulp, as is often required.
Topics: Humans; Resin Cements; Dental Cements; Composite Resins; Glass Ionomer Cements; Materials Testing; Dental Materials
PubMed: 38403539
DOI: 10.1016/j.dental.2024.02.015 -
Journal of Clinical and Experimental... Sep 2023Although, the influence of cement and background shade on the final color and translucency of zirconia reinforced lithium silicate (ZLS) and lithium disilicate (LDS)...
BACKGROUND
Although, the influence of cement and background shade on the final color and translucency of zirconia reinforced lithium silicate (ZLS) and lithium disilicate (LDS) ceramics has been previously investigated, there is still little data on the translucency of LDS and ZLS ceramics in decreased thickness (0.4 and 0.6 mm). The aim of this study was to investigate ceramic thickness', background and cement shades' effects on the zirconia reinforced lithium silicate (ZLS) and lithium disilicate (LDS) ceramics' translucency.
MATERIAL AND METHODS
Totally 160 square-shaped A1 shade LDS and ZLS samples produced in 0.4 and 0.6 mm thicknesses were cemented with light and neutral shade resin cement on A2 and A3 shade composite resin backgrounds. The color notations of specimen were measured and translucency parameter (TP) values were calculated. Factorial ANOVA and Tamhane's T2 multiple comparison statistical analyzes were used.
RESULTS
Highest TP values (11.82±0.97) were obtained in ZLS specimens that were 0.4 mm in thickness, cemented on A2 background with light shade resin cement. While, the lowest TP values (9.60±0.55) were calculated in LDS samples that had 0.6 mm thickness, cemented on A3 background with neutral shade resin cement.
CONCLUSIONS
Material type, thickness, and background shade affected TP values of specimens. The cement and background shade used might change the final translucency of ZLS and LDS ceramics that had 0.4 and 0.6 mm thickness. Ceramics, lithium disilicate, spectrophotometry, zirconia, dental materials.
PubMed: 37799753
DOI: 10.4317/jced.60806 -
Bioinformation 2024A comparative analysis and assessment of the compressive strength (CS) and diametral tensile strength (DTS) between conventional glass ionomer cement (C-GIC) and a...
A comparative analysis and assessment of the compressive strength (CS) and diametral tensile strength (DTS) between conventional glass ionomer cement (C-GIC) and a silver-reinforced GIC (S-GIC) variant is of interest. Ten specimens of both C-GIC (GC Fuji II, Japan) and S-GIC (Riva Silver, SDI, Australia) were fabricated for the evaluation of compressive strength, and an identical number of samples were created for the examination of tensile strength. These specimens were then tested using a universal testing apparatus. The results exhibited that both the compressive and diametral tensile strengths were significantly greater for the S-GIC cement in comparison to the C-GIC, with a notable p-value of 0.001. The findings suggest that S-GIC may be considered a viable alternative to conventional GIC.
PubMed: 38854768
DOI: 10.6026/973206300200391 -
Polymers Sep 2023Polyetheretherketone (PEEK) is widely used in dentistry owing to its exceptional properties, including its natural appearance; however, existing surface treatment...
Polyetheretherketone (PEEK) is widely used in dentistry owing to its exceptional properties, including its natural appearance; however, existing surface treatment methods for bonding PEEK have limitations. Autofocus laser cutters, known for their precise engraving and cutting capabilities, offer potential for surface treatment of PEEK; thus, the objective of this study was to investigate the creation of laser groove structures on PEEK to enhance its bonding capability with dental resin cement. A dental computer-aided design and manufacturing system was used to fabricate PEEK samples, and three groove patterns (circle, line, and grid) were generated on PEEK surfaces, with air-abrasion used as the control group. The surface characteristics, cell viability, and bond strength were evaluated, and the data were statistically analyzed using one-way analysis of variance and post hoc Tukey's tests (α = 0.05). Laser-treated PEEK exhibited a uniform texture with a groove depth of approximately 39.4 µm, hydrophobic properties with a contact angle exceeding 90°, a surface roughness of 7.3-12.4 µm, consistent topography, and comparable cell viability compared with untreated PEEK. Despite a decrease in bond strength after thermal cycling, no significant intergroup differences were observed, except for the line-shaped laser pattern. These findings indicate that the autofocus laser cutter effectively enhances the surface characteristics of PEEK by creating a uniform texture and grooves, showing promise in improving bonding properties, even considering the impact of thermal cycling effects.
PubMed: 37765524
DOI: 10.3390/polym15183670 -
International Dental Journal Jun 2024The aim was to assess the peri-implant clinicoradiographic status and prostaglandin E2 (PGE2) levels in peri-implant sulcular fluid (PISF) samples collected from...
BACKGROUND
The aim was to assess the peri-implant clinicoradiographic status and prostaglandin E2 (PGE2) levels in peri-implant sulcular fluid (PISF) samples collected from individuals with cement-retained and crew-retained implants.
METHODS
In this observational study, participants with cement-retained and screw-retained implants were enrolled. A questionnaire was utilized to gather demographic information and assess the educational background of the participants. Peri-implant modified plaque and bleeding indices, probing depth, and crestal bone loss were measured. Subsequently, PISF samples were collected, and corresponding volumes were recorded. Commercial kits employing enzyme-linked immunosorbent assay were employed to quantify PGE2 levels. The sample size was determined, and group comparisons were conducted using the Student t test and the Mann-Whitney U-test. Logistic regression models were constructed to evaluate the correlation between PGE2 levels and clinicoradiographic and demographics. The predefined level of significance was established at P < .05.
RESULTS
Sixty-seven participants, consisting of 33 with cement-retained implants and 34 with screw-retained implants, were included in the study. The mean ages for individuals with cement and screw-retained implants were 54.2 ± 8.7 and 58.7 ± 7.4 years, respectively. The majority of participants had completed university-level education. Reportedly, 87.9% and 82.4% of individuals with cement and screw-retained implants, respectively brushed teeth twice daily. No significant differences were observed in clinicoradiographic parameters, PGE2 volume, and levels between cement-retained and screw-retained implants. There was no correlation between PGE2 levels and peri-implant clinicoradiographic parameters among individuals with either cement-retained or screw-retained implants.
CONCLUSIONS
Cement-retained and screw-retained implants exhibit a consistent peri-implant clinicoradiographic status, accompanied by stable levels of PGE2 in PISF provided oral hygiene maintenance regimens are stringently followed.
PubMed: 38866672
DOI: 10.1016/j.identj.2024.04.026