Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 18.415
Filter
1.
BMC Oral Health ; 24(1): 1033, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39227885

ABSTRACT

BACKGROUND: The accuracy of intraoral scanning is critical for computer-aided design/computer-aided manufacturing workflows in dentistry. However, data regarding the scanning accuracy of various adjacent restorative materials and intraoral scanners are lacking. This in vitro study aimed to evaluate the effect of adjacent restorative material type and CEREC's intraoral scanners on the accuracy of intraoral digital impressions for inlay cavities. METHODS: The artificial tooth was prepared with an occlusal cavity depth of 2 mm, a proximal box width at the gingival floor of 1.5 mm, and an equi-gingival margin extended disto-occlusally at the transition line angle on both the lingual and buccal sides for an inlay restoration. The adjacent teeth were veneered with crowns made of gold and zirconia, and an artificial tooth (resin) was utilized as the control group. The inlay cavity and adjacent teeth (Gold, Zirconia, and resin) were scanned 10 times using Chairside Economical Restoration of Esthetic Ceramics (CEREC) Primescan (PS), Omnicam (OC), and Bluecam (BC). A reference scan was obtained using a laboratory scanner (3-shape E3). Scanning was performed according to the manufacturer's instructions, including powder application for the BC group. Standard tesselation language files were analyzed using a three-dimensional analysis software program. Experimental data were analyzed using a two-way analysis of variance and the Tukey's post-hoc comparison test. RESULTS: The restorative materials of the adjacent teeth significantly affected the accuracy of the intraoral digital impressions (p < .05). The zirconia group exhibited the highest trueness deviation, followed by the resin and gold groups, with each demonstrating a statistically significant difference (p < .05). The resin group demonstrated the highest maximum positive deviation and deviation in precision. Gold exhibited the lowest average deviation value for trueness compared with those of the other adjacent restorative materials. Intraoral scanner type significantly influenced the trueness and precision of the scan data (p < .05). The average deviation of trueness according to the intraoral scanner type increased in the following order: BC > PS > OC. The average deviation in precision increased in the following order: PS>OC>BC (p < .05). CONCLUSION: The restorative materials of the adjacent tooth and the type of intraoral scanner affect the accuracy of the intraoral digital impression. The trueness of the digital images of the BC group, obtained by spraying the powder, was comparable to that of the PS group. Among the adjacent restorative materials, zirconia exhibited the lowest trueness. In contrast, PS demonstrated the highest precision among the intraoral scanners, while resin displayed the lowest precision among the adjacent restorative materials.


Subject(s)
Computer-Aided Design , Inlays , Zirconium , Humans , Dental Impression Technique , In Vitro Techniques , Dental Materials , Crowns , Ceramics , Dental Prosthesis Design/methods , Dental Restoration, Permanent/methods
2.
PLoS One ; 19(9): e0306385, 2024.
Article in English | MEDLINE | ID: mdl-39231159

ABSTRACT

Scanning Electron Microscope (SEM) is a crucial tool for studying microstructures of ceramic materials. However, the current practice heavily relies on manual efforts to extract porosity from SEM images. To address this issue, we propose PSTNet (Pyramid Segmentation Transformer Net) for grain and pore segmentation in SEM images, which merges multi-scale feature maps through operations like recombination and upsampling to predict and generate segmentation maps. These maps are used to predict the corresponding porosity at ceramic grain boundaries. To increase segmentation accuracy and minimize loss, we employ several strategies. (1) We train the micro-pore detection and segmentation model using publicly available Al2O3 and custom Y2O3 ceramic SEM images. We calculate the pixel percentage of segmented pores in SEM images to determine the surface porosity at the corresponding locations. (2) Utilizing high-temperature hot pressing sintering, we prepared and captured scanning electron microscope images of Y2O3 ceramics, with which a Y2O3 ceramic dataset was constructed through preprocessing and annotation. (3) We employed segmentation penalty cross-entropy loss, smooth L1 loss, and structural similarity (SSIM) loss as the constituent terms of a joint loss function. The segmentation penalty cross-entropy loss helps suppress segmentation loss bias, smooth L1 loss is utilized to reduce noise in images, and incorporating structural similarity into the loss function computation guides the model to better learn structural features of images, significantly improving the accuracy and robustness of semantic segmentation. (4) In the decoder stage, we utilized an improved version of the multi-head attention mechanism (MHA) for feature fusion, leading to a significant enhancement in model performance. Our model training is based on publicly available laser-sintered Al2O3 ceramic datasets and self-made high-temperature hot-pressed sintered Y2O3 ceramic datasets, and validation has been completed. Our Pix Acc score improves over the baseline by 12.2%, 86.52 vs. 76.01, and the mIoU score improves from by 25.5%, 69.10 vs. 51.49. The average relative errors on datasets Y2O3 and Al2O3 were 6.9% and 6.36%, respectively.


Subject(s)
Ceramics , Deep Learning , Microscopy, Electron, Scanning , Ceramics/chemistry , Porosity , Hot Temperature , Aluminum Oxide/chemistry
3.
Carbohydr Polym ; 346: 122619, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39245496

ABSTRACT

This review article explores the developments and applications in agar-based composites (ABCs), emphasizing various constituents such as metals, clay/ceramic, graphene, and polymers across diversified fields like wastewater treatment, drug delivery, food packaging, the energy sector, biomedical engineering, bioplastics, agriculture, and cosmetics. The focus is on agar as a sustainable and versatile biodegradable polysaccharide, highlighting research that has advanced the technology of ABCs. A bibliometric analysis is conducted using the Web of Science database, covering publications from January 2020 to March 2024, processed through VOSviewer Software Version 1.6.2. This analysis assesses evolving trends and scopes in the literature, visualizing co-words and themes that underscore the growing importance and potential of ABCs in various applications. This review paper contributes by showcasing the existing state-of-the-art knowledge and motivating further development in this promising field.


Subject(s)
Agar , Food Packaging , Agar/chemistry , Humans , Drug Delivery Systems , Clay/chemistry , Biocompatible Materials/chemistry , Graphite/chemistry , Ceramics/chemistry
4.
Sci Rep ; 14(1): 20336, 2024 09 02.
Article in English | MEDLINE | ID: mdl-39223136

ABSTRACT

Antimicrobial potential of bioactive glass (BAG) makes it promising for implant applications, specifically overcoming the toxicity concerns associated with traditional antibacterial nanoparticles. The 58S composition of BAG (with high Ca and absence of Na) has been known to exhibit excellent bioactivity and antibacterial behaviour, but the mechanisms behind have not been investigated in detail. In this pioneering study, we are using Atomic Force Microscopy (AFM) to gain insights into 58S BAG's adhesive interactions with planktonic cells of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria; along with the impact of crystallinity on antibacterial properties. We have recorded greater bacterial inhibition by amorphous BAG compared to semi-crystalline glass-ceramics and stronger effect against gram-negative bacteria via conventional long-term antibacterial tests. AFM force distance curves has illustrated substantial bonding between bacteria and BAG within the initial one second (observed at a gap of 250 ms) of contact, with multiple binding events. Further, stronger adhesion of BAG with E.coli (~ 6 nN) compared to S. aureus (~ 3 nN) has been found which can be attributed to more adhesive nano-domains (size effect) distributed uniformly on E.coli surface. This study has revealed direct evidence of impact of contact time and 58S BAG's crystalline phase on bacterial adhesion and antimicrobial behaviour. Current study has successfully demonstrated the mode and mechanisms of initial bacterial adhesion with 58S BAG. The outcome can pave the way towards improving the designing of implant surfaces for a range of biomedical applications.


Subject(s)
Anti-Bacterial Agents , Bacterial Adhesion , Ceramics , Escherichia coli , Glass , Microscopy, Atomic Force , Staphylococcus aureus , Microscopy, Atomic Force/methods , Ceramics/chemistry , Bacterial Adhesion/drug effects , Glass/chemistry , Staphylococcus aureus/drug effects , Escherichia coli/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
5.
BMC Oral Health ; 24(1): 1073, 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39261788

ABSTRACT

BACKGROUND: Advancements in digital dentistry helped in custom-milling screw-channels in implant-supported restorations; however, the fit of these restorations is still unclear especially for contemporary computer aided designing/computer aided manufacturing (CAD/CAM) materials. This study aimed to compare the internal and marginal fit of Ultra translucent multilayered zirconia versus lithium disilicate implant-supported hybrid abutment crowns (HACs) constructed with custom-milled screw-channels on Titanium-base. MATERIALS AND METHODS: A total of 24 HACs with custom-milled screw-channels were constructed from lithium disilicate (Group LDS) and Ultra translucent multilayered zirconia (Group UT) using digital workflow (n = 12). The internal and marginal gaps of HACs on their corresponding Titanium-bases were assessed using replica technique and stereomicroscope, respectively. After testing for normality, quantitative data were expressed as mean and standard deviation and compared using independent t-test at a level of significance (P ≤ 0.05). RESULTS: There was no statistically significant difference between Group LDS and Group UT in terms of marginal and internal fit. The internal and marginal gaps in both groups were within the accepted values reported in literature. CONCLUSIONS: UT and LDS HACs with custom-milled screw-channels demonstrated comparable and acceptable internal fit and marginal adaptations to Ti-base, which lied within the range reported in literature.


Subject(s)
Computer-Aided Design , Crowns , Dental Implant-Abutment Design , Dental Marginal Adaptation , Dental Prosthesis, Implant-Supported , Titanium , Zirconium , Titanium/chemistry , Zirconium/chemistry , Humans , Dental Porcelain/chemistry , In Vitro Techniques , Dental Abutments , Ceramics/chemistry , Dental Prosthesis Design
6.
BMC Oral Health ; 24(1): 1065, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39261857

ABSTRACT

BACKGROUND: Recently, prosthodontic approaches involve more conservative procedures that include less invasive finish line preparations that use less ceramic thickness. AIM OF THE STUDY: This in vitro study aimed to evaluate the effect of vertical preparation and modified vertical preparation designs on the marginal adaptation and fracture resistance of two types of ceramic crowns using CAD/CAM technology. MATERIALS AND METHODS: Two typodont maxillary first premolars were embedded in acrylic resin. Forty positive replicas of epoxy resin dies were used that were divided into two groups depending on the preparation design (n = 20); Group V (Vertical): dies with feather edge finish line and Group MV (Modified vertical): dies with feather edge finish line, where a reverse shoulder of 1 mm depth was placed on the buccal surface 1.5 mm from the occlusal surface. Each group was further subdivided into two subgroups according to the type of ceramic material (n = 10): Subgroup Va and subgroup MVa for lithium disilicate (e.max CAD) and subgroup Vb and subgroup MVb for zirconia (zolid ht+). Crown restorations were made with CAD-CAM technology. The marginal adaptation was assessed using a stereomicroscope both prior to cementation and after cementation and aging. Fracture resistance was tested with a universal testing machine, and the data were statistically analyzed. RESULTS: Marginal adaptation showed no significant differences between subgroups before or after cementation and aging. Three-way ANOVA indicated that preparation design (p = 0.516) and material (p = 0.269) had no significant effect, but cementation had a significant effect (p < 0.0001) on the marginal adaptation. According to two-way ANOVA test, Subgroup (MVb) showed the highest result followed by subgroup (Vb) and subgroub (MVa) and the least was subgroub (Va). Fracture modes showed no significant differences among the subgroups (p = 0.982). CONCLUSIONS: Marginal adaptation of lithium disilicate and zirconia crowns remained clinically acceptable regardless of preparation design. While the modified vertical preparation with a reverse shoulder notably enhanced the fracture resistance of both materials, with zirconia demonstrating superior fracture resistance compared to lithium disilicate with average values exceeding premolar biting force.


Subject(s)
Ceramics , Computer-Aided Design , Crowns , Dental Marginal Adaptation , Dental Porcelain , Dental Prosthesis Design , Dental Stress Analysis , Zirconium , Zirconium/chemistry , Dental Porcelain/chemistry , Humans , In Vitro Techniques , Ceramics/chemistry , Dental Restoration Failure , Materials Testing , Bicuspid
7.
BMC Oral Health ; 24(1): 1089, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39277736

ABSTRACT

BACKGROUND: To predict the long-term performance of restorative materials in the oral environment, it is important to evaluate their resistance to chemical and mechanical degradation and to know the toxic potential of the type and amount of ions eluted from the filling material. In this study, home bleaching was applied to dental materials with different contents and it was aimed to determine the type and amount of ions released from these materials. METHODS: In this study, amalgam, posterior composite resin, anterior composite resin, bulk fill composite resin, indirect composite resin, hybrid ceramic and all-ceramic were used as restorative materials. 10 specimens of each material were prepared according to the manufacturer's instructions. Each material group was divided into two subgroups as the bleached group and the control group. After bleaching, all specimens were stored in 1 ml of 75% ethanol/water solution. Solutions were renewed after 1, 14 and 28 days. The type and amount of ions released from the materials were determined using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Data were analyzed using the Friedman, Wilcoxon Signed Ranks, and Mann-Whitney U tests (α = 0.05). RESULTS: It was determined that the amount of ions release from the restorative materials decreased over time (p < 0.05). According to the results of the Mann-Whitney U test, there was no difference between the bleaching and control groups in most of the restorative materials (p > 0.05). CONCLUSION: Within the limits of this study, home bleaching system does not have a significant effect on ion release from restorative materials.


Subject(s)
Carbamide Peroxide , Composite Resins , Dental Amalgam , Dental Materials , Dental Restoration, Permanent , Materials Testing , Peroxides , Tooth Bleaching Agents , Urea , Carbamide Peroxide/pharmacology , Peroxides/chemistry , Composite Resins/chemistry , Tooth Bleaching Agents/chemistry , Dental Amalgam/chemistry , Urea/analogs & derivatives , Urea/chemistry , Dental Restoration, Permanent/methods , Dental Materials/chemistry , Ions , Ceramics/chemistry , Humans , Time Factors
8.
BMC Oral Health ; 24(1): 1087, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39277754

ABSTRACT

BACKGROUND: Different materials have been used as wound dressings after vital pulp therapies. Some of them have limitations such as delayed setting, difficult administration, slight degree of cytotoxicity, crown discoloration and high cost. Therefore, to overcome these disadvantages, composite scaffolds have been used in regenerative dentistry. This study aims to construct and characterize the physicochemical behavior of a novel injectable alginate hydrogel loaded with different bioactive glass nanoparticles in various concentrations as a regenerative pulpotomy filling material. METHODS: Alginate hydrogels were prepared by dissolving alginate powder in alcoholic distilled water containing mesoporous bioactive glass nanoparticles (MBG NPs) or boron-doped MBG NPs (BMBG NPs) at 10 and 20 wt% concentrations. The mixture was stirred and incubated overnight in a water bath at 50 0 C to ensure complete solubility. A sterile dual-syringe system was used to mix the alginate solution with 20 wt% calcium chloride solution, forming the hydrogel upon extrusion. Then, constructed hydrogel specimens from all groups were characterized by FTIR, SEM, water uptake percentage (WA%), bioactivity and ion release, and cytotoxicity. Statistical analysis was done using One-Way ANOVA test for comparisons between groups, followed by multiple pairwise comparisons using Bonferroni adjusted significance level (p < 0.05). RESULTS: Alginate/BMBG loaded groups exhibited remarkable increase in porosity and pore size diameter [IIB1 (168), IIB2 (183) (µm)]. Similarly, WA% increased (~ 800%) which was statistically significant (p < 0.05). Alginate/BMBG loaded groups exhibited the strongest bioactive capability displaying prominent clusters of hydroxyapatite precipitates on hydrogel surfaces. Ca/P ratio of precipitates in IIA2 and IIB1 (1.6) were like Ca/P ratio for stoichiometric pure hydroxyapatite (1.67). MTT assay data revealed that the cell viability % of human gingival fibroblast cells have declined with increasing the concentration of both powders and hydrogel extracts in all groups after 24 and 48 h but still higher than the accepted cell viability % of (˃70%). CONCLUSIONS: The outstanding laboratory performance of the injectable alginate/BMBGNPs (20 wt%) composite hydrogel suggested it as promising candidate for pulpotomy filling material potentially enhancing dentin regeneration in clinical applications.


Subject(s)
Alginates , Biocompatible Materials , Boron , Dentin , Hydrogels , Nanoparticles , Alginates/chemistry , Humans , Boron/chemistry , Biocompatible Materials/chemistry , Dentin/drug effects , Porosity , Cell Survival/drug effects , Regeneration/drug effects , Materials Testing , Spectroscopy, Fourier Transform Infrared , Dental Pulp/cytology , Dental Pulp/drug effects , Microscopy, Electron, Scanning , Regenerative Endodontics/methods , Glass/chemistry , Fibroblasts/drug effects , Ceramics/chemistry , Water/chemistry
9.
Clin Exp Dent Res ; 10(5): e70002, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39295316

ABSTRACT

OBJECTIVE: This study assessed the effect of the anodization of titanium abutments on the color parameters and color difference of lithium disilicate (LDS) all-ceramic crowns. MATERIALS AND METHODS: In this study, 19 straight abutments were divided into two groups: anodized (n = 9) and non-anodized control (n = 9), with one hybrid zirconia abutment as a reference. Anodization was achieved by applying 63 V energy using seven 9 V flat batteries in series, with an electrolyte solution comprising 1 g trisodium phosphate in 250 mL distilled water for 5 s, resulting in a gold-yellow color. Abutments were then scanned, and full-contour monolithic IPS e.max maxillary central incisor crowns were fabricated with 2 mm thickness and glazed. Reflectance was measured using a spectroradiometer, and color coordinates (L*, a*, b*, h*, and C*) were calculated using CS-10W software. Color differences of the crowns in both groups were quantified using the CIEDE2000 (ΔE00) color difference formula and analyzed by t-test (α = 0.05) compared to the standard sample. RESULTS: The L*, a*, b*, and c* parameters in anodized abutments were significantly higher than those in non-anodized abutments, while the h* parameter in anodized abutments was significantly lower than that in non-anodized abutments (p < 0.001 for all). There was a significant difference in ΔE00 of the two groups (p = 0.043). CONCLUSION: Anodization of titanium abutments improved the color parameters of LDS all-ceramic crowns and significantly decreased their ΔE compared with non-anodized abutments.


Subject(s)
Color , Crowns , Dental Abutments , Dental Porcelain , Titanium , Titanium/chemistry , Dental Porcelain/chemistry , Zirconium/chemistry , Humans , Dental Prosthesis Design , In Vitro Techniques , Materials Testing , Ceramics/chemistry , Prosthesis Coloring , Surface Properties
10.
Oper Dent ; 49(5): 617-626, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39300738

ABSTRACT

OBJECTIVES: This study aimed to assess the surface roughness, surface free energy (SFE), and shear bond strength (SBS) on a lithium disilicate glass-ceramic surface following varying etching protocols (time variation) and application of silane either with or without adhesive material. METHODS AND MATERIALS: Lithium disilicate glassceramic (LDGC) computer-aided design and computer-aided manufacture (CAD/CAM) blocks were cut using a slow-speed cutting mechanism. CAD/CAM blocks were then evaluated for surface roughness, 6 groups (n=20); SFE,12 groups (n=5); and SBS, 10 groups (n=10). The cut CAD/CAM blocks were randomly allocated to 28 groups. Groups were based on the following: 30 or 90 seconds of etching with 9% hydrofluoric acid (HF); application or absence of silane coupling agent (Sil); and application or absence of adhesive (Adh).The control group (Cont) had untreated surfaces. Unetched surfaces were surveyed with only silane (Sil), only adhesive (Adh), or silane+adhesive (SilAdh). Further etched groups were HF30 with HF for 30 seconds, HF30-Sil, HF30-Adh, and HF30-SilAdh. Alternative 90-second etching times produced similar groups: HF90, HF90-Sil, HF90-Adh, and HF90-SilAdh. A digital profilometer was used to assess the surface roughness of specimens, and two readings were recorded. Sessile drop analysis was used to examine SFE specimens, and the OWRK model was modified to measure liquid surface tension. A universal testing machine (UltraTester, Ultradent Products, Inc, South Jordan, UT, USA) was utilized for the SBS test, with the crosshead speed set at 0.5 mm/min until failure. Representative treated specimens from each group were submitted to surface morphological evaluation and chemical analysis using scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDXS) (n=3). After data collection, evaluation using one- or two-way analysis of variance and the post-hoc Tukey test (α=5%) was conducted. RESULTS: A longer etching time of 90 seconds produced a rougher surface. After the 90-second etching process, SFE displayed the greatest values; nevertheless, the use of silane did not affect SFE. For every group examined, the application of silane followed by adhesive resulted in an increase in SBS and more stable bonding over time. SEM/EDXS showed that etching times did affect the amount of cerium on the surface and altered surface morphology. CONCLUSIONS: Higher and more consistent bond strengths have been observed with longer etching periods. Silane and adhesive application on the ceramic surface showed stronger and enhanced bond strength, specifically when longer etching times were employed.


Subject(s)
Acid Etching, Dental , Ceramics , Dental Porcelain , Hydrofluoric Acid , Silanes , Surface Properties , Hydrofluoric Acid/chemistry , Silanes/chemistry , Dental Porcelain/chemistry , Acid Etching, Dental/methods , Ceramics/chemistry , Dental Bonding/methods , Materials Testing , Shear Strength , Dental Stress Analysis , Computer-Aided Design , Time Factors , Microscopy, Electron, Scanning
11.
Sci Rep ; 14(1): 20958, 2024 09 09.
Article in English | MEDLINE | ID: mdl-39251687

ABSTRACT

Aseptic loosening is a feared and not yet fully-understood complication of total knee arthroplasty (TKA). Hypersensitivity reactions may be the underlying cause within some susceptible patients. Metal-free implants have been developed as a possible solution. The aim of this prospective, observational long-term study was the assessment of a completely metal-free ceramic knee replacement system compared to its identical metal counterpart 8 years after implantation, conducted as a follow-up of a previous report. A total of 88 patients (mean age 69 years) were enrolled in this prospective, observational long-term 8-year follow-up study. The "ceramic group" with a completely metal-free total knee replacement system was compared to the "conventional group" with an identical metal TKA system at the final follow-up. Clinical assessment included Knee Society Score (KSS), Oxford Knee Score (OKS), European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-L), European Quality of Life 5 Dimension Visual Analogue Scale (EQ-VAS) and High Activity Arthroplasty Score (HAAS) as well as perioperative or postoperative complications and need for revision. The tibial/femoral positioning, signs of periprosthetic fissures/fractures or radiolucent lines were documented radiographically. All postoperative clinical scores in the ceramic group primarily improved from baseline to 4-year follow-up, but then decreased at the final 8-year follow-up. At the final follow-up, statistically non-significant differences were found in comparison of both groups for the KSS (ceramic: 166 ± 31, conventional: 162 ± 29; p > 0.05), OKS (ceramic: 37, conventional: 39; p > 0.05), EQ-VAS (ceramic: 77 ± 17, conventional: 72 ± 18; p > 0.05), and HAAS (ceramic: 8.29 ± 3.32, conventional: 9.28 ± 4.44; p > 0.05). A significant difference was found for EQ-5D-L (ceramic: 0.819 ± 0.284, conventional: 0.932 ± 0.126; p ≤ 0.05). Progressive radiolucent lines have been found around the uncemented tibial stem (0.8 mm at initial diagnosis (mean 19 months); 1.3 mm at 4-year follow-up; 1.6 mm at 8-year follow-up) without any clinical signs of loosening. One revision surgery was performed after a traumatic polyethylene inlay-breakage. No allergic reactions could be detected. The used ceramic TKA system meets the functional performance standards of an established identical metal TKA system after an 8-year follow-up period, offering a safe option for patients with prior hypersensitivity reactions to metallic materials. Full cementation of ceramic components is recommended.


Subject(s)
Arthroplasty, Replacement, Knee , Knee Prosthesis , Humans , Arthroplasty, Replacement, Knee/adverse effects , Arthroplasty, Replacement, Knee/methods , Female , Aged , Male , Follow-Up Studies , Knee Prosthesis/adverse effects , Middle Aged , Prospective Studies , Prosthesis Design , Quality of Life , Prosthesis Failure , Ceramics , Knee Joint/surgery , Aged, 80 and over , Postoperative Complications/etiology , Metals/adverse effects , Treatment Outcome
12.
BMC Oral Health ; 24(1): 1078, 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39272065

ABSTRACT

BACKGROUND: Partial coverage concepts have met the main goal of conservative dentistry. Vonlays, which combine features of veneers and onlays, are a recent alternative to full coverage designs and overlay partial coverage restorations. This in vitro study was conducted to compare the fracture resistance of the newly introduced pressable zirconia-reinforced lithium silicate with pressable lithium disilicate ceramic and to determine the optimal preparation design for partial coverage on upper premolars. METHODS: Fifty-two duplicated epoxy resin dies were prepared following vonlay and overlay preparation guidelines. For each preparation (n = 26), the specimens were divided into two subgroups to be restored with lithium disilicate (IPS e.max Press) or zirconia-reinforced lithium silicate (Vita Ambria) (n = 13 each). Ceramic vonlays and overlays were bonded using dual cure resin cement, subjected to thermomechanical fatigue, and the load to fracture was tested by using a universal testing machine. The specimens were fractographically analyzed via scanning electron microscopy (SEM). The normality of the fracture resistance data was checked using the Shapiro‒Wilk test and Q‒Q plots, and two-way ANOVA was used to assess the effect of the type of preparation and ceramic material on the fracture resistance. RESULTS: The group of overlays restored with zirconia-reinforced lithium silicate showed the highest mean fracture load (1218.69 N), while the group of vonlays restored with lithium disilicate had the lowest mean fracture resistance (967.15 N). The effect of preparation design and material type on fracture resistance was significant for both factors, p = 0.003 and p < 0.0001, respectively. Different features of the fracture surfaces, such as arrest lines, hackles, and directions of crack propagation, were observed. CONCLUSIONS: Zirconia-reinforced lithium silicate exhibited greater resistance to fracture compared to lithium disilicate, making it a potential substitute for partial coverage restorations. Additionally, the overlay showed superior fracture resistance when compared to the vonlay preparation design.


Subject(s)
Bicuspid , Ceramics , Dental Porcelain , Dental Stress Analysis , Materials Testing , Zirconium , Ceramics/chemistry , Dental Porcelain/chemistry , Zirconium/chemistry , Humans , In Vitro Techniques , Dental Restoration Failure , Microscopy, Electron, Scanning , Maxilla , Dental Prosthesis Design , Inlays , Dental Veneers
13.
Molecules ; 29(17)2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39275056

ABSTRACT

Bone has the ability to heal itself; however, bone defects fail to heal once the damage exceeds a critical size. Bone regeneration remains a significant clinical challenge, with autograft considered the ideal bone graft material due to its sufficient porosity, osteogenic cells, and biological growth factors. However, limitations to bone grafting, such as limited bone stock and high resorption rates, have led to a great deal of research into developing bone graft substitutes. The P28 peptide is a small molecule bioactive biomimetic alternative to mimic the bone morphogenetic protein 2 (BMP-2). In this study, we investigated the potential of P28-loaded hybrid scaffolds to mimic the natural bone structure for enhancing the bone regeneration process. We hypothesized that the peptide-loaded scaffolds and nude scaffolds both have the potential to promote bone healing, and the bone healing process is accelerated by the release of the peptide. To verify our hypothesis, C2C12 cells were evaluated for the presence of calcium deposits by histological stain at 7 and 14 days in cultures with hybrid scaffolds. Total RNA was isolated from C2C12 cells cultured with hybrid scaffolds for 7 and 14 days to assess osteoblast differentiation. The project findings demonstrated that the hybrid scaffold could enhance osteoblast differentiation and significantly improve the therapeutic effects of the scaffold in bone regeneration.


Subject(s)
Bone Regeneration , Cell Differentiation , Ceramics , Chitosan , Tissue Scaffolds , Bone Regeneration/drug effects , Tissue Scaffolds/chemistry , Chitosan/chemistry , Chitosan/pharmacology , Animals , Mice , Ceramics/chemistry , Ceramics/pharmacology , Cell Differentiation/drug effects , Osteoblasts/drug effects , Osteoblasts/cytology , Osteoblasts/metabolism , Cell Line , Osteogenesis/drug effects , Bone Morphogenetic Protein 2/pharmacology , Tissue Engineering/methods , Peptides/chemistry , Peptides/pharmacology , Humans
14.
PLoS One ; 19(9): e0306647, 2024.
Article in English | MEDLINE | ID: mdl-39284157

ABSTRACT

Pottery vessels often comprise major burial goods at archaeological sites, thus providing valuable information for reconstructing past mortuary practices. However, because of the uncertainty of its function or use, which has been interpreted mostly through typological studies alone, the analytical potential of pottery as a burial good has not been fully exploited. This study applied bio-chemical and geochemical analyses for the first time to funerary pottery vessels of the Iron Age of North Iran to examine their function and use. The study materials are from the necropolis of Ghalekuti, Dailaman, excavated in the 1960s. Direct radiocarbon dating conducted on human and animal bones in the graves and typological analysis of the pottery anchored the chronological position of the pottery materials to the 2nd and 1st millennium BC. A petrographic analysis revealed that pottery vessels can be classified into six fabric types, including those with coarse tempers that are effective for cooking. Pottery pastes with finer inclusions less suited for cooking appeared during the early first millennium BC (Iron Age III). To obtain further insight into the function of the pottery, we conducted organic residue analyses. The results demonstrated that the vessels retained remains of botanical and animal origin. In particular, jars with tubular spouts, characteristic of the Iron Age III period, were likely specialised for botanical products. Interestingly, both carcass and dairy products from ruminant animals (cattle and caprine) were processed in short-neck jars and bowls, including spouted bowls, suggesting their use in a liquid state. Products from ruminants, particularly dairy products, may have played a significant role in the daily and ritual use of pottery vessels during the study period in Northern Iran. These results indicate that a range of pottery vessels used for specific purposes before the burial was offered for graves, helping us better understand the mortuary practices of Iron Age Iran.


Subject(s)
Archaeology , Iran , Humans , Animals , History, Ancient , Ceramics/history , Ceramics/chemistry , Ceramics/analysis , Burial/history , Radiometric Dating , Bone and Bones/chemistry
16.
BMC Oral Health ; 24(1): 1104, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39289670

ABSTRACT

BACKGROUND: The effect of an immune-boosting beverage (SAM) containing Sambucus Nigra, an energy beverage (ENE), an in-office bleaching (BLE) agent with 25% hydrogen peroxide superior, glazing (GLA) or polishing (POL) methods, and professional dental prophylaxis (PDP) on the color of CAD-CAM restorative materials is unknown. METHODS: In total 210 specimens were prepared, consisting of CAD-CAM feldspathic (FC), zirconia-reinforced lithium disilicate ceramic (ZLS) and hybrid ceramic (HC). The ceramic specimens were divided according to the polishing methods of glazing (GLA) and mechanical polishing (POL). All materials were divided into two groups: with and without BLE. A 25% hydrogen peroxide superior (HPS) gel was used for BLE. After the baseline (BAS) measurement, the specimens were immersed in 3 different beverages (distilled water (DIS), SAM, ENE). After 28 days, a fine-grained (RDA 7) prophylaxis paste was applied. Statistical analysis of ∆E00 color difference values was performed by 3-way ANOVA and Bonferroni test (α = 0.05). RESULTS: The effect of all other actions except material-BLE-beverage on color for BAS-Day 28 was statistically different (p < 0.05). The effect of material, material-BLE, beverage on color for Day 28-PDP was statistically different (p < 0.05). After 28 days, the lowest color change was found in FC-GLA and HC immersed in DIS (p = 0.0001) and the highest in FC-POL immersed in ENE (p = 0.0002). PDP was efficient in color recovery in HC immersed to DIS, ENE and SAM (p = 0.0010). For FC, HC and ZLS, BLE caused a higher color change (p < 0.0001). Regardless of the material, the highest color change for BLE-beverage was found in BLE-treated specimens immersed in ENE (p = 0.0496) and the lowest color change was found in non-BLE-treated specimens immersed in SAM (p = 0.0074). CONCLUSIONS: In materials pre-exposed to 25% HPS, the effect of PDP on color recovery was lower than in unexposed materials. After 28 days, mechanical polishing produced higher color change in FC than glazing, however, in ZLS effects of glazing and mechanical polishing on color were similar. For material/polishing method, HC was the most effective. ENE caused higher color change than DIS and SAM. PDP was more effective than ENE in restoring color to DIS- and SAM-immersed specimens.


Subject(s)
Color , Dental Polishing , Hydrogen Peroxide , Hydrogen Peroxide/chemistry , Dental Polishing/methods , Energy Drinks , Dental Prophylaxis/methods , Tooth Bleaching Agents , Humans , Materials Testing , Dental Restoration, Permanent/methods , Dental Materials/chemistry , Tooth Bleaching/methods , Ceramics/chemistry
17.
J Biomed Mater Res B Appl Biomater ; 112(9): e35476, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39223753

ABSTRACT

Mucoperiosteal wound healing, as it occurs after pediatric cleft palate surgery, can be challenging due to the limitations of current treatments such as tissue flaps secured with sutures and fibrin glue. In this study, we characterized the in vitro performance of a novel composite hydrogel biomaterial designed to be employed as an in situ wound filler and enhance mucoperiosteal wound healing. We evaluated a range of photopolymerizable formulations containing methacrylated gelatin (GelMA), glycol chitosan, and bioglass microparticles. Our aim was to identify one or more formulations with an appropriate balance of properties against a set of functional requirements that we established for this application. To test the formulations against these criteria, we measured photopolymerization kinetics, mechanical properties, degradation rate, in vitro biocompatibility, and ex vivo tissue adhesion. All formulations polymerized in less than 90 s using violet light. In addition, we found that GelMA-based hydrogels were more adhesive to mucoperiosteal tissue than clinical standard fibrin glue. Inclusion of small amounts of bioglass in the formulation increased mechanical compatibility with mucoperiosteal tissue, enhanced cytoconductivity, and promoted cell proliferation. Taken together, our results support the suitability of these photopolymerized composite hydrogels as in situ mucoperiosteal wound fillers. Overall, this study lays the groundwork for investigating the in vivo, pre-clinical effectiveness of these composite hydrogels in improving mucoperiosteal wound healing outcomes.


Subject(s)
Chitosan , Gelatin , Hydrogels , Materials Testing , Wound Healing , Hydrogels/chemistry , Hydrogels/pharmacology , Wound Healing/drug effects , Chitosan/chemistry , Chitosan/pharmacology , Gelatin/chemistry , Animals , Humans , Ceramics/chemistry , Ceramics/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Periosteum
18.
J Biomed Mater Res B Appl Biomater ; 112(9): e35482, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39269164

ABSTRACT

The stromal vascular fraction (SVF) is a derivate of fat tissue comprising both adipose-derived mesenchymal stem cells and endothelial cells and serves as a promising cell source for engineering vascularized bone tissues. Its combination with osteoconductive biphasic calcium phosphate (BCP) ceramic may represent a point-of-care agent for bone reconstruction. Here we assessed the proliferation and osteogenic differentiation capacities of SVF on 3D printed BCP implants, in comparison with isolated adipose-derived mesenchymal stem cells (AD-MSCs). AD-MSCs and SVF isolated from human donors were seeded on plastic or 3D printed BCP ceramics with sinusoidal or gyroid macrotopography and cultured in the presence or absence of osteogenic factors. Vascular, hematopoietic and MSC surface markers were assessed by flow cytometry whereas osteogenic activity was investigated through alizarin red staining and alkaline phosphatase activity. Osteogenic factors were necessary to trigger osteogenic activity when cells were cultured on plastic, without significant difference observed between the two cell populations. Interestingly, osteogenic activity was observed on BCP implants in the absence of differentiation factors, without significant difference in level activity between the two cell populations and macrotopography. This study offers supportive data for the use of combined BCP scaffolds with SVF in a perspective of a one-step surgical procedure for bone regeneration.


Subject(s)
Cell Differentiation , Ceramics , Mesenchymal Stem Cells , Osteogenesis , Printing, Three-Dimensional , Humans , Osteogenesis/drug effects , Cell Differentiation/drug effects , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/cytology , Ceramics/pharmacology , Ceramics/chemistry , Hydroxyapatites/chemistry , Hydroxyapatites/pharmacology , Tissue Scaffolds/chemistry , Adipose Tissue/cytology , Adipose Tissue/metabolism , Cells, Cultured
19.
BMC Oral Health ; 24(1): 1052, 2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39245758

ABSTRACT

BACKGROUND AND OBJECTIVES: Mineral Trioxide Aggregate (MTA) is one of the main retrograde filling materials that is used today as a root end filling material and perforation repair material. This study was conducted with the aim of investigating the antibacterial and antifungal properties of four types of bio-ceramic materials, AGM MTA, Ortho MTA, Pro root MTA and Cem cement for oral and dental health. METHODS: In this study, the antibacterial activity of four types of bio-ceramic materials against two bacterial strains of Enterococcus faecalis (ATTC 29212), Escherichia coli (ATTC 35318) and antifungal activity against Candida albicans (ATTC 10231) were investigated using the well diffusion method. RESULTS: In the context of the relationship between the type of microorganism and the diameter of the growth inhibitory zone for each type of bio-ceramic material, there was no significant difference for Enterococcus faecalis, and a significant difference was observed for Escherichia coli and Candida albicans (p < 0.05). CONCLUSION: The results show that each of the bio-ceramic materials AGM, Pro root, Cem cement and Ortho have antibacterial and antifungal properties. AGM MTA bio-ceramic material on Candida albicans fungus and Ortho MTA bio-ceramic material had the most effect on Escherichia coli bacteria. Therefore, the mentioned bio-ceramic materials can play a significant role in oral and dental health by providing a suitable material for restoration.


Subject(s)
Aluminum Compounds , Calcium Compounds , Candida albicans , Ceramics , Drug Combinations , Enterococcus faecalis , Escherichia coli , Oxides , Root Canal Filling Materials , Silicates , Calcium Compounds/pharmacology , Silicates/pharmacology , Candida albicans/drug effects , Enterococcus faecalis/drug effects , Oxides/pharmacology , Aluminum Compounds/pharmacology , Escherichia coli/drug effects , Root Canal Filling Materials/pharmacology , Humans , Dental Cements/pharmacology , Anti-Bacterial Agents/pharmacology , Materials Testing , Antifungal Agents/pharmacology
20.
Med Sci Monit ; 30: e945130, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39252410

ABSTRACT

BACKGROUND This 3-dimensional (3D) optical study aimed to evaluate the effects of microwave glazing on the surface roughness of zirconia-reinforced glass. Glazed surfaces of ceramic provide a smooth and esthetically superior restoration. There are many methods of glazing. However, this study aims to evaluate the effect of microwave glazing on ceramic restorations over conventional oven and hand polishing. MATERIAL AND METHODS A sample size of 90 ceramic material tiles was derived according to the standard sample size formula. The 3 dental ceramics used were IPS e.max CAD (lithium disilicate ceramic; IvoclarVivadent), Suprinity (zirconia-reinforced lithium silicate; VITA Zahnfabrik), and Celtra Duo zirconia-reinforced lithium silicate; Dentsply Sirona). Each group was further divided equally to undergo conventional oven glazing, hand polishing, and microwave glazing. The final glazed surfaces were then evaluated for surface roughness with the Ra parameter, using a Contour GT 3D Optical Microscope (Bruker) and 3D non-contact surface metrology with interferometry. RESULTS The ANOVA test for intergroup comparison showed microwave glazing was a significantly better glazing method than conventional oven and hand polishing (P<0.05). A statistically significant difference was shown between conventional and microwave glazing; however, the difference was greater between conventionally glazed and hand-polished specimens. Furthermore, a highly significant difference between microwave-glazed and hand-polished specimens was observed. CONCLUSIONS Results showed that irrespective of the ceramic, microwave-glazed ceramics were better than traditional oven-glazed ceramics, and hand-polishing resulted in a rougher surface than glazing. Irrespective of the surface treatment methods, IPS e.max CAD ceramic showed a relatively smoother surface than did Suprinity and Celtra Duo.


Subject(s)
Ceramics , Dental Porcelain , Microwaves , Surface Properties , Zirconium , Zirconium/chemistry , Ceramics/chemistry , Dental Porcelain/chemistry , Materials Testing/methods , Humans , Dental Materials/chemistry , Glass/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL