Humphreyowens4402

During mastication, when the deciduous second molar tooth was absent, the maximum stress was transferred to incomplete roots. When there was a space maintainer, stress was transferred to the space maintainer itself and to the distal side of the deciduous first molar tooth. The displacement of permanent first molar teeth was minimal in the presence of all teeth; in the absence of the deciduous second molar tooth, this displacement increased 4-5-fold, which decreased again almost to the level of the 1st/4th state (intact arch) in the presence of the space maintainer.

The results showed the importance of the use of space maintainers, as they significantly decrease the momentary displacement of the teeth as well as the stress exerted on the developing permanent first molar teeth.

The results showed the importance of the use of space maintainers, as they significantly decrease the momentary displacement of the teeth as well as the stress exerted on the developing permanent first molar teeth.

Oxidative stress has been identified as a predisposing factor for dental caries. Saliva, as a rich source of antioxidants, plays an essential role in the protection against dental caries. Salivary enzymatic antioxidants include superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx).

The aim of this study was to evaluate the correlation of salivary enzymatic antioxidant activity with different levels of dental caries in children.

In this cross-sectional study, 90 healthy children aged 7-12 years (36 girls, 54 boys) were investigated. Demographic information was gathered and dental examinations were provided for all participants. Then, unstimulated whole saliva samples were collected in the morning. The salivary SOD, CAT and GPx activity was measured spectrophotometrically. For statistical analysis, Spearman's correlation test, the Mann-Whitney U test and the Kruskal-Wallis test were used with the SPSS for Windows software, v. 16.

Our results showed no significant correlation between SOD, CAT and GPx and the decayed, missing, filled teeth index for permanent/primary dentition (DMFT/dmft). The CAT activity was elevated in proportion to the number of decayed teeth. The SOD activity showed a positive correlation with the frequency of tooth brushing. The activity of SOD, CAT and GPx was higher in boys than in girls. An inverse relationship between enzymatic antioxidant activity and age was also observed.

Although enzymatic antioxidants had no positive correlation with DMFT/dmft, they were positively correlated with the number of decayed teeth and the improvement of oral hygiene.

Although enzymatic antioxidants had no positive correlation with DMFT/dmft, they were positively correlated with the number of decayed teeth and the improvement of oral hygiene.

The growth and proliferation of gingival fibroblasts are important in the process of oral wound healing, and photobiomodulation (PBM) might be able to modify this process.

The aim of the current study was to evaluate the biomodulatory effect of a single session of laser PBM by means of 810 nm and 940 nm diode lasers alone and their combined application with different fluencies on human gingival fibroblasts (HGFs).

Cells were provided by the Pasteur Institute, the National Cell Bank of Iran (NCBI) (C-165). Selleckchem JNK Inhibitor VIII Laser irradiation was carried out using 810 nm, 940 nm and 810 nm + 940 nm in the continuous wave (CW) mode, 100 mW, and energy densities of 0.5, 1.5 and 2.5 J/cm2. Cell viability was evaluated at 24 h with the MTT assay. Trypan blue staining was used to evaluate proliferation 24, 48 and 72 h after laser therapy. Propidium iodine was used to stain DNA and the cell nucleus.

Laser irradiation (810 nm, 0.5 J/cm2) increased the viability of gingival fibroblasts, while this dose had an inhibitory effect wiation dose of 810 nm, 0.5 J/cm2, resulted in a positive effect on cell viability at 24 h, no statistically significant stimulatory effect on viability and proliferation was observed for the other single wavelength group. When a combination of the 2 wavelengths was used, better results were observed as compared to the control, which needs to be further investigated in future studies.

Bone loss rapidly increases 6 months post tooth extraction, which causes the atrophy of the alveolar bone. Two kinds of biomaterials which can stimulate bone regeneration are bioceramics and polymers. Making a composite of biomaterials results in better physical and biomolecular characteristics in comparison with a bioceramic or a polymer alone. Hydroxyapatite nanoparticles (HANPs) are one of the bioceramics commonly used for bone regeneration; they can degrade faster than hydroxyapatite (HA) microparticles, but have an insufficient pore size. Polyvinyl alcohol (PVA) and poly lactic-co-glycolic acid (PLGA) are polymers which have been used for biomedical applications. However, PLGA alone has insufficient cell attachment and PVA alone slowly degrades in the bone tissue.

The aim of the present study was to analyze the biodegradation properties of the HANP/PLGA/PVA composites and investigate the pore size.

The HANP/PLGA/PVA composites were prepared using the freeze-drying method, with 20% (w/w) of HANP and bone scaffold to repair the alveolar defect post tooth extraction.

There is very little literature available on the reliability of the rapid prototyping technology in the production of three-dimension (3D)-printed surgical guides for accurate implant placement.

The aim of the study was to evaluate the deviation of implant placement performed with a surgical guide fabricated by means of the rapid prototyping technique (the PolyJet™ technology).

Twenty sheep mandibles were used in the study. Pre-surgical cone-beam computed tomography (CBCT) scans were acquired for the mandibles by using the Kodak 9000 3D cone-beam system. Two implants with dimensions of 4 mm in diameter and 10 mm in length were virtually planned on the 3D models of each mandible by using the Mimics software, v. 16.0. Twenty surgical guides were designed and printed using the PolyJet technology. A total of 40 implants were placed using the surgical guides, 1 on each side of the mandible (2 implants per mandible). The post-surgical CBCT scans of the mandibles were performed and superimposed on the pre-surgical CBCT scans. The amount of deviation between the virtually planned placement and the actual implant placement was measured, and a descriptive analysis was done.

The results showed that the mean deviation at the implant coronal position was 1.82 ±0.74 mm, the mean deviation at the implant apex was 1.54 ±0.88 mm, the mean depth deviation was 0.44 ±0.32 mm, and the mean angular deviation was 3.01 ±1.98°.

The deviation of dental implant placement performed with a 3D-printed surgical guide (the PolyJet technology) is within the acceptable 2-millimeter limit reported in the literature.

The deviation of dental implant placement performed with a 3D-printed surgical guide (the PolyJet technology) is within the acceptable 2-millimeter limit reported in the literature.

Implants called miniplates, with different geometries, are used for the treatment of a fractured or diseased mandible. Generally, Ti-based miniplates in various quantities and with various geometries are fixed into the bone tissue according to the location and shape of the fracture by embedding.

The aim of this study was to increase the strength of the material used in the production of miniplates by means of the equal-channel angular pressing (ECAP) treatment, and to provide a highrigidity fixation system with fewer miniplates.

In this study, the ECAP method, which is one of the methods of severe plastic deformation, was applied at 4 passes at 300°C in route Bc to increase the strength of pure Ti. Then, miniplates were produced with 2 different geometries (regular and long) and 2 different properties of the Ti material (untreated and ECAP-treated). The produced miniplates were placed in the fracture line formed in the angular region of an artificial, synthetic-bone mandible. The 2-point and 3-point bending and torsion tests were conducted on these fixation systems.

As a result, after the ECAP process, the yield and tensile strength of pure Ti increased by 65%, while elongation decreased by 13%. After the ECAP process, the grain size of the material was reduced from 110 μm to 200 nm.

This study showed that the fixation system became more rigid due to using ECAP-treated miniplates, and this ensured lesser displacement of the fixation system.

This study showed that the fixation system became more rigid due to using ECAP-treated miniplates, and this ensured lesser displacement of the fixation system.Cancer immunotherapy is set to emerge as the future of cancer therapy. However, recent immunotherapy trials in different cancers have yielded sub-optimal results, with durable responses seen in only a small fraction of patients. Engineered multifunctional nanomaterials and biological materials are versatile platforms that can elicit strong immune responses and improve anti-cancer efficacy when applied to cancer immunotherapy. While there are traditional systems such as polymer- and lipid-based nanoparticles, there is a wide variety of other materials with inherent and additive properties that can allow for more potent activation of the immune system. By synthesizing and applying multifunctional strategies, it allows for a more extensive and more effective repertoire of tools to use in the wide variety of situations that cancer presents itself. Here, several types of nanoscale and biological material strategies and platforms that provide their inherent benefits for targeting and activating multiple aspects of the immune system are discussed. Overall, this review aims to provide a comprehensive understanding of recent advances in the field of multifunctional cancer immunotherapy and trends that pave the way for more diverse and tactical regression of tumors through soliciting responses by either the adaptive or innate immune system, and even both simultaneously.When flowing whole blood contacts medical device surfaces, the most common blood-material interactions result in coagulation, inflammation, and infection. Many new blood-contacting biomaterials have been proposed based on strategies that address just one of these common modes of failure. This study proposes to mitigate unfavorable biological reactions that occur with blood-contacting medical devices by designing multifunctional surfaces, with features optimized to meet multiple performance criteria. These multifunctional surfaces incorporate the release of the small molecule hormone nitric oxide (NO) with surface chemistry and nanotopography that mimic features of the vascular endothelial glycocalyx. These multifunctional surfaces have features that interact with coagulation components, inflammatory cells, and bacterial cells. While a single surface feature alone may not be sufficient to achieve multiple functions, the release of NO from the surfaces along with their modification to mimic the endothelial glycocalyx synergistically improves platelet-, leukocyte-, and bacteria-surface interactions. This work demonstrates that new blood-compatible materials should be designed with multiple features, to better address the multiple modes of failure of blood-contacting medical devices.