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Abstract This study aimed to design sustained released biodegradable calcium carbonate nanoparticles loaded with chlorhexidine (CHX-loaded NPs) and to investigate the early osteogenic differentiation and antimicrobial effects on the important bacteria involved in infections of dental implants. The microemulsion method was used to prepare the calcium carbonate nanoparticles loaded with chlorhexidine. The prepared nanoparticles were characterized using conventional methods. The release pattern determination and the biodegradation test were performed for the prepared nanoparticles. For the early osteogenic differentiation test of the prepared nanoparticles, alkaline phosphatase (ALP) activity was detected in human dental pulp stem cells (HDPSCs). The antimicrobial effects of the nanoparticles were evaluated against Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa. The sizes of free calcium carbonate nanoparticles and CHX-loaded NPs were 105 ± 1.63 and 118 ± 1.47 nm and their zeta potentials were − 27 and − 36, respectively. A 50% degradation of nanoparticles was achieved after 100 days. These nanoparticles showed a two-stage sustained release pattern in vitro. Microscopic images revealed that the morphology of free calcium carbonate nanoparticles primarily took on a spherical calcite form, while CHX-loaded NPs predominantly exhibited a cauliflower-like vaterite polymorph. The nanoparticles increased the activity of ALP in cells in two weeks significantly (p

Objectives: Vitamin D deficiency appears to have a major effect on periodontal tissue health. The present study aimed to assess the association of the serum level of 25-hydroxyvitamin D and chronic periodontitis in postmenopausal women. Materials and Methods: This research was done on 30 postmenopausal women with chronic periodontitis who all had at least 20 natural teeth. Intravenous blood samples were taken from the study population at baseline and after completion of non-surgical periodontal treatment. This was followed by assessment of serum levels of 25-hydroxyvitamin D. Next, clinical parameters of all teeth except for third molars were measured, which included pocket depth (PD), gingival index (GI), and plaque index (PI). Data were analyzed by paired t-test and its non-parametric equivalent, the Wilcoxon test. P0.05). Conclusion: According to the results obtained in the present study, there is no association between serum vitamin D concentrations and chronic periodontitis in postmenopausal women.

Introduction: This study aimed to prepare a new root repair material including Portland cement, bismuth oxide, and nano-hydroxyapatite and analyze its physicochemical properties and its effects on the proliferation and differentiation of human dental pulp stem cells (hDPSCs). Material and Methods: Bismuth oxide as a radiopaque component and nano-hydroxyapatite particles were added to white Portland cement at 20% and 5% weight ratio, respectively. Characterization of the prepared cement was done using con-ventional methods. To examine the bioactivity of this new material, atomic absorption spectroscopy (AAS) was used for the investigation of the rate of calcium ions dissolution in simulated body fluid media. The viability of hDPSCs was assessed by an MTT assay after 1, 3 and 7 days. The odontogenic potential of this substance was evaluated by measuring alkaline phosphatase activity and alizarin red S staining. Results: Based on the bioactivity results, the cement presented high bio-activity, corroborating sufficiently with the calcium release patterns. The cell viability was significantly increased in new root repair ma-terial containing hydroxyapatite nanoparticles after 3 and 7 days (p

It seems quite challenging in tissue engineering to synthesize a base material with a range of essential activities, including biocompatibility, nontoxicity, and antimicrobial activities. Various types of materials are synthesized to solve the problem. This study aimed to provide the latest relevant information for practitioners about antibacterial scaffolds in dental tissue engineering. The PubMed search engine was used to review the relevant studies with a combination of the following terms as search queries: tissue engineering, scaffolds, antimicrobial, dentistry, dental stem cells, and oral diseases. It is noteworthy to state that only the terms related to tissue engineering in dentistry were considered. The antimicrobial scaffolds support the local tissue regeneration and prevent adverse inflammatory reactions; however, not all scaffolds have such positive characteristics. To resolve this potential defect, different antimicrobial agents are used during the synthesis process. Innovative methods in guided tissue engineering are actively working towards new ways to control oral and periodontal diseases.

Abstract Objectives Infections after implant placement are the main reasons for the failure of implant treatments. The present study aimed to evaluate the antibacterial effects of nanocurcumin inside the implant fixture against Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis. Materials and Methods Twenty seven implants were classified in three groups for testing the antibacterial effect of nanocurcumin, chlorhexidine (as negative control), and distilled water (as negative control). Each group was then divided into three subgroups to study the effect of the applied torque on the antimicrobial effect of nanocurcumin. All implant abutment assemblies were submerged in bacteria suspension and were incubated at 37°C for 24 hours. The contents of each implant were removed to count the colony of bacteria on the surface of plates containing nutrient agar. Results Results indicated that the inhibitory rate of bacteria by nanocurcumin was above 99% in all bacteria. Besides, by increasing the amount of applied torque from 10 to 35 N.cm, the CFU of bacteria in exposure to nanocurcumin significantly were decreased (p‐value

Background. Periodontitis can lead to progressive destruction of periodontal tissues supporting the tooth. Developing biomaterials for tissue engineering has noticeably improved the existing treatment options. The present study investigated the gelatin-hydroxyapatite nano-fibers as promising scaffolds for guided tissue regeneration (GTR). Methods. The scaffolds were prepared through electrospinning technique, and then the physicochemical properties and the cytotoxic effects on dental-derived mesenchymal stem cells were assessed. Results. The nano-scaffolds were successfully prepared with a mono-dispersed nano-scale diameter (102±0.10 nm), negative surface charge (-20±0.17 mV), and uniform network-shaped morphology. The mesenchymal stem cells derived from the human dental pulp stem cells (hDPSC) with gelatin-hydroxyapatite nano-fibers showed that the prepared scaffolds had a significant proliferative effect. Besides, the applied method can be used to prepare fiber-based structures via other polymeric materials. Conclusion. The incorporation of different materials to decrease the degradation rate of the fibers can match the speed of tissue regeneration. In this case, the prepared nano-fibers can be applied as a membrane biomaterial.

This study was conducted to investigate the effect of adding silica nanoparticles on the physicochemical properties, antimicrobial action, and the hardness of dental stone type 4. Dental stone type 4 powder was physically mixed with nanoparticle powder at weight percentages (0, 0.5, 1, and 2 percent). The required amount of powder was added to water according to the manufacturer's instructions. The prepared set materials were subjected to the physicochemical studies; Fourier transmission infrared spectroscopy (FTIR) was taken up to investigate the functional groups and X-ray diffraction (XRD) was used to evaluate the crystallinity. Also, scanning electron microscopy (SEM) was used to examine the morphology of the prepared samples. Agar diffusion test was carried out for the prepared samples against the Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) to test the average growth inhibition zones. Finally, the Vickers surface hardness test was performed for each group using a hardness tester. The adding silica nanoparticles to dental stone type 4 increased the diameter of inhibition zones for the groups in both bacteria significantly (p

Polymethyl methacrylate (PMMA) is a widely used material in prosthetics and is used to fabricate denture bases. The main disadvantage of this material is its polymerization shrinkage which causes clinical problems during use. The present study aimed to investigate and compare the microhardness, surface roughness, and water sorption of a commercial acrylic resin denture, which were processed by two different methods including conventional and pressure-packed injection molding techniques. A total of 60 polymethyl methacrylate samples were prepared in two groups: conventional acrylic resin (vertex) for the compression molding method and injection acrylic resin (vertex) for the injection molding method (10 samples of each material per test). The microhardness test was performed using a Vickers microhardness test device, the surface roughness test was performed by using a profilometer, and the water sorption test was performed using a digital scale. Data were analyzed using an independent sample t-test with Statistical Package for the Social Sciences (SPSS), version 17. The significant level was considered to be 0.05. According to the results, there was a significant difference between microhardness, surface roughness, and water sorption of the samples in the two groups. The results of the independent t-test showed that the microhardness of injection vertex acrylic resin samples was significantly higher than that of conventional pressure-packed vertex acrylic resin samples (P value