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Abstract Background Cognitive function plays a crucial role in human life, and its maintenance and improvement are essential in both young and older adults. Since cognitive decline can be associated with oral function decline, preventing the decline in both cognitive and oral functions is an urgent social issue. Several training methods to improve each function have been proposed. Previous studies have indicated that greater brain activity during training is associated with increased benefits for cognitive function. Although adding cognitive function elements to oral function training may promote the activation of brain activity during oral function training, the effects have not been validated. The main purpose of this study is to develop a novel training program that combines oral function training with cognitive training, which is expected to activate key brain regions involved in oral and cognitive functions, such as the left dorsolateral prefrontal cortex (DLPFC) and right medial prefrontal cortex (mPFC). Methods Four types of training programs combining oral and cognitive training: PaTaKaRa × calculation, lip exercise × N-back, tongue exercise × inhibition, and tongue exercise × memory, were developed. Each program had seven levels of difficulty [level 0 (no cognitive load) and level 6 (maximum difficulty)]. Twelve healthy young adults participated in the study and were instructed to perform all four programs. Brain activity in the left DLPFC and right mPFC were measured during each training session using two-channel near-infrared spectroscopy (NIRS). Results No significant brain activity was observed during training at level 0. Brain activity in the left DLPFC was significantly increased at levels 1 and 2 and in the left DLPFC and right mPFC at level 6 during PaTaKaRa × calculation training. Brain activity in the left DLPFC was significantly increased at level 6 during tongue exercise × inhibition training. Brain activity in the left DLPFC and right mPFC was significantly increased at level 6 during lip exercise × N-back training. Conclusion Oral function training did not significantly increase brain activity; nevertheless, oral function with cognitive training stimulated brain activity in the prefrontal cortex. Trial registration : UMIN-CTR. ID: UMIN000039678. date: 06/03/2020.

Introduction: During tissue repair or regeneration, several bioactive molecules are released and interact with each other and act as complex additives or inhibitors for tissue reconstruction. In this study, the bone-healing effects of the combination treatment with tumor necrosis factor-α (TNF-α) inhibition, vascular endothelial growth factor A (VEGF-A) and bone morphogenetic protein-7 (BMP-7) release by gene silencing, and gene transfection with calcium phosphate nanoparticles (CaP) in the rat femoral head was histologically, morphologically, and biochemically evaluated. Methods: A triple-functionalized paste of CaP carrying plasmid DNA encoding for BMP-7 and for VEGF), and siRNA against TNF-α was developed and denoted as CaP3mix. To compare the effects of 3mixCaP, CaP with plasmid DNA encoding BMP-7, VEGF, or siRNA encoding TNF-α was prepared and denoted as CaP/PEI/pBMP-7/SiO2, CaP/PEI/pVEGF/SiO2, or CaP/PEI/siRNA-TNF-α/SiO2, respectively. The bone healing in bone defects in the rat femoral head was investigated after 10 and 21 days of implantation. Results: The levels of bone formation-related markers OCN, Runx2, and SP7 increased at the protein and gene levels in 3mixCaP after 10 days, and 3mixCaP significantly accelerated bone healing compared with the other treatments after 21 days of implantation. Conclusion: The triple-functionalized CaP paste loading plasmid DNA encoding BMP-7 and VEGF and siRNA encoding TNF-α is a promising bioactive material for bone tissue repair.

Abstract Background Members of the neurotrophic tropomyosin receptor kinase (NTRK) gene family, NTRK1, NTRK2, and NTRK3 encode TRK receptor tyrosine kinases. Intra‐ or inter‐chromosomal gene rearrangements produce NTRK gene fusions encoding fusion proteins which are oncogenic drivers in various solid tumors. Methods This study investigated the prevalence of NTRK fusion genes and identified fusion partners in Japanese patients with solid tumors recorded in the Center for Cancer Genomics and Advanced Therapeutics database of comprehensive genomic profiling test. Results In the analysis population (n = 46,621), NTRK fusion genes were detected in 91 patients (0.20%). The rate was higher in pediatric cases (

Abstract Background Appropriate load distribution among the supporting elements is essential for the long-term success of implant-assisted removable partial dentures; however, there is little information available on load distribution. Purpose This study aimed to evaluate the effect of implant location on load distribution in implant-assisted removable partial dentures by reviewing in vitro models and finite-element analysis studies. Materials and methods English-language studies which examined the load distribution of implant-assisted removable partial dentures and were published between January 2001 and October 2022 were extracted from PubMed, ScienceDirect, and Scopus online databases, and manual searching. Two reviewers selected the articles based on the predetermined inclusion and exclusion criteria, followed by data extraction and analysis. Results Forty-seven studies were selected after evaluating the titles and abstracts of 264 articles; two were identified manually. After screening the text, 12 studies were included: six in vitro model experiments and six finite-element analysis studies. All included studies used a mandibular free-end missing model (Kennedy Class I or II). The influence of implant location on load distribution to the abutment tooth, implant, and mucosa under the denture base was summarized in three cases: implant at the premolar, first molar, and second molar region. Due to differences in the measurement method of load distribution and loading condition to the denture, the results differed among the studies. Conclusions The implant location in implant-assisted removable partial dentures can affect load distribution to the supporting elements, such as the abutment tooth, implant, and mucosa under the denture base.

Introduction: Periodontal ligament is regenerated in association with hard tissue regeneration. Tenomodulin (Tnmd) expression has been confirmed in periodontal ligament and it reportedly inhibits angiogenesis or is involved in collagen fibril maturation. The introduction of Tnmd by gene transfection in bone tissue regeneration therapy might inhibit topical hard tissue formation and induce the formation of dense fibrous tissue. Therefore, the effect of Tnmd introduction by gene transfection technique in vitro and in vivo was investigated in this study. Methods: Osteogenesis- and chondrogenesis-related gene expression levels in osteoblastic cells (MC3T3E1) and rat bone marrow derived cells were detected using qPCR three days after gene transfection with plasmid DNA (Tnmd) using non-viral gene transfection vectors: a calcium phosphate-based gene transfection vector (CaP(Tnmd)) or a cationic polymer-based reagent (JetPEI (Tnmd)). Next, an atelocollagen scaffold with or without CaP (Tnmd) or JetPEI (Tnmd) was implanted into a rat calvaria bone defect, and the remaining bone defect volume and the tissue reaction at 28 days after surgery were evaluated. Results: Runx 2 and SP7 mRNA was reduced by JetPEI (Tnmd) in both cells, but not in CaP(Tnmd). The volume of expressed Tnmd was at 9 ng/mL in both gene transfection vector. The remaining bone defect volume of JetPEI (Tnmd) was significantly bigger than that of the other groups and CaP (EGFP), and that of CaP (Tnmd) was significantly bigger than that of CaP (EGFP). Conclusions: Tnmd introduction treatment inhibits bone formation in artificial bone defect, however, the effect of that was dependent on non-viral gene transfection vector.

BackgroundOrofacial pain conditions are complex disorders that involve biological, social, and psychological factors. Temporomandibular Disorders (TMDs) are one of the most common orofacial pain conditions, and our previous literature review indicated that exercise therapy has shown promise in reducing TMD-related pain. However, more evidence is needed to firmly establish its effectiveness.ObjectivesThis systematic review aims to investigate the effectiveness of exercise therapy on pain relief and jaw mobility in patients with pain-related TMDs.MethodsTo include randomized controlled trials (RCTs) written in English, a literature search was performed using PubMed, Scopus, Web of Science, Cochrane Library, Ovid, EBM reviews, and Academic Search Complete initially from 4th November 2020 until March 2022. A PICOS for this review was as follows; P: Patients with TMD myalgia or arthralgia, I: Excursion exercise, Stretch exercises, Resistance exercise, or Coordination exercise, C: No treatment or education only. O: Pain intensity and Range of Motion (ROM), S: RCTs. After title screening, a full-text assessment was done to extract data. According to Risk of Bias (RoB) 2.0, risk of bias was assessed in each included paper by 2 reviewers independently.ResultsA total of 3,388 titles were identified from the electronic database search. After the screening and full-text evaluation, only 5 studies (145 participants) were eligible to be included. Among the exercise modalities, coordination exercise showed a significant effect on pain relief and improvement of joint mobility.DiscussionDue to the heterogeneity and small sample size of the included studies, a meta-analysis was not feasible. However, this systematic review suggested that exercise therapy, especially coordinate exercise, can be effective in managing painful TMD conditions. Further research is needed to establish optimal parameters for this patient population, as well as standardization and consistency in terminology and treatment structure.

Background/purpose: Color-changeable chewing gum is used for the evaluation of masticatory performance. However, it is currently unclear whether colorimetric and visual assessment methods yield consistent results. This study aimed to clarify the consistency between colorimetric and visual methods used for the evaluation of color changes in color-changeable chewing gum. Materials and methods: The sample comprised 644 older persons (mean age, 75.4 ± 6.4 years). The chewing gum was masticated 60 times at the participant's own chewing rate and then expectorated. The color of the chewing gum was evaluated with the ΔE values and a∗ values, measured using a colorimeter, and the 10 Color Shades (10CSh) and 5 Color Scales (5CSc), using visual evaluation. Spearman's correlation analysis was performed to examine the correlation between the results obtained by the four methods. The significance level was set at α = 0.05. Results: The ΔE values, a∗ values, 10CSh scores, and 5CSc scores were all significantly correlated. The highest correlation coefficient (0.979) was between the ΔE values and a∗ values. The lowest correlation coefficient (0.847) was between the a∗ values and 5CSc scores. Decreased masticatory performance was observed with increased age. Conclusion: Significant correlations were found for all four methods used in the assessment of masticatory performance with color-changeable chewing gum. While visually based assessments are valid, colorimetric methods are more sensitive to smaller changes in masticatory performance.

Abstract Background Oral appliances (OAs) are generally designed to displace the mandible anteriorly and downward, to increase the airway patency. The present study aimed to examine the relationship between genioglossus (GG) muscle activity and mandibular position, considering both anterior and vertical displacements during sleep. Methods Seven healthy male adults aged 29.4 ± 1.99 years were evaluated. Maxillary and mandibular OAs were fabricated from 2-mm-thick resin plates with pressure-welding. The activity of the left GG was recorded using two silver ball electrodes attached to the lingual edge of the mandibular OA. Respiratory status and right masseter muscle activity were measured by an airflow sensor and surface electrodes, respectively. Electroencephalography was used to determine the sleep status. Stage 2 (the second stage of sleep) was defined as the state of sleeping. Four test conditions with different mandibular positions (0 and 50% anterior protrusion) and bite openings (4 mm and 12 mm) were examined. Results GG activity in SL4A (4 mm bite opening, 50% protrusion during sleep) and SL12 (12 mm bite opening, 0% protrusion during sleep) were significantly higher than that in SL4 (4 mm bite opening, 0% protrusion during sleep). Respiratory volume did not significantly differ between all test conditions. Conclusion GG activity is influenced not only by anterior protrusion of the mandible but also by vertical displacement during sleep. Thus, when determining the effectiveness of intraoral appliances in the treatment of obstructive sleep apnea, both protrusion and the size of the mandibular opening should be evaluated and taken into account.

Supercooling during the freezing of pharmaceutical solutions often leads to suboptimal freeze-drying results, such as long primary drying times or a collapse in the cake structure. Thermal treatment of the frozen solution, known as annealing, can improve those issues by influencing properties such as the pore size and collapse temperature of the lyophilisate. In this study we aimed to show that annealing causes a rearrangement of water molecules between ice crystals, as well as between the freeze-concentrated amorphous matrix and the crystalline ice phase in a frozen binary aqueous solution. Ice crystal sizes, as well as volume fractions of the crystalline and amorphous phases of 10% (w/w) sucrose and trehalose solutions, were quantified after annealing using freeze-drying microscopy and image labelling. Depending on the annealing time and temperature, the amorphous phase was shown to decrease its volume due to the crystallisation of vitreous water (i.e., glassy state relaxation) while the crystalline phase was undergoing coarsening (i.e., Ostwald ripening). These results allow, for the first time, a quantitative comparison of the two phenomena. It was demonstrated that glassy state relaxation and Ostwald ripening, although occurring simultaneously, are distinct processes that follow different kinetics.

In this work, we have experimentally studied the effect of particle size of the oxidized zircaloy-4 on the observed yield of Hydrogen generation by Co-60 gamma radiolysis of water. The oxidation products were obtained by high-temperature oxidation of zircaloy-4 under dry air atmosphere for 2 and 4 hours. We crushed them into various sizes from 3 to 484 μm after the oxidation. The crushed particles of the product of 4 hours oxidation consisted of almost monoclinic zirconium oxide and the 2 hours oxidation product contained from 26 to 56% of tetragonal zirconium oxide. These particles had specific surface areas from 0.73 to 2.58 m2/g and band gaps 5.1 eV all. The oxidation products of the weight fraction of 10% and distilled water were mixed into a 4 ml glass vial to examine the Hydrogen generation by Co-60 gamma radiolysis. The experiments have presented that the observed hydrogen yield, G(H2) was increased by decreasing the median particle diameter of both the oxidation products. Especially, the G(H2) of water added the particles with 3 or 5 μm became larger than that of only distilled water. This enhancement was not caused by the bandgap of the oxidation product. Calculated G(H2) per surface area of the oxidation product, G(H2)/S was constant on all particle sizes. Furthermore, G(H2)/S of the water added the oxidation products with the median particle diameter 3 or 5 μm were larger than the commercial zirconium oxides (m-ZrO2, t-ZrO2) whose median particle diameters are 3 μm. In conclusion, Hydrogen generation of water by Co-60 gamma radiolysis was influenced by the particle size added into water. We have considered that the surface area of the oxidation product was the predominant factor of this effect because the G(H2) per specific surface area was constant regardless of particle size of the crushed oxidation products in this experiment.

Purpose: To examine the effect of tightening and loosening the dental implant screw on implant osseointegration in an elderly rat model.Materials and Methods: Titanium dental implants were inserted in the bilateral tibiae of 34 elderly Wistar rats (1 year and 3 months old). Rats were randomly divided into five groups: control (no loading); immediate loading (IL) (vertical load [3 Hz for 15 minutes/day] immediately after implantation); early loading (EL) (load started on postoperative day 7); five times abutment removal (R5) (tightening and loosening of the abutment screw once per day for 5 days each week); and two times abutment screw removal (R2) (tightening and loosening of the abutment screw once per day for 2 days each week). After 4 weeks, the rats were euthanized, and the bone structure surrounding the dental implants was evaluated using microcomputed tomography analysis.Results: Osseointegration failed more frequently in the EL, R2, and R5 groups than in the control and IL groups (P = .06). The EL, R2, and R5 groups also tended to have lower relative gray values than the control and IL groups.Conclusion: Tightening and loosening the abutment screw might negatively affect dental implant osseointegration in the early healing stage in older adults. [ABSTRACT FROM AUTHOR]

Calcium Titanate (CaTiO3) has been introduced as an attractive biomaterial for the enhancement of calcium phosphate deposition in vivo and in vitro. We hypothesized that CaTiO3 directly coated on titanium (Ti) by metal-organic chemical vapor deposition (MOCVD) could be a suitable candidate for biocompatible coatings for medical devices, particularly dental implants. To prove this hypothesis, surface characterization, cell culture, and animal study were completed in this study. The result of this study showed that CTO 800, a CaTiO3 film prepared by heating at 800 °C, had a high hydrophilic surface. Mouse bone marrow stromal ST-2 cells cultured on substrates and CTO 800 exhibited cell differentiation, represented by alkaline phosphatase activity, compared with cells cultured on non-coated Ti and CTO 700 (a CaTiO3 film prepared by heating at 700 °C). The push-in test value of CTO 800, a parameter that indicates the degree of osseointegration, was significantly higher than that of Ti. Calcium titanate coated on Ti by MOCVD has the potential to accelerate the process of osseointegration; thus, our results support the use of CaTiO3 coating for biocompatible biomaterial for medical applications, particularly dental implants.