Effectiveness of novel oral hygiene instruction avoiding inattentional blindness using an application for unique plaque control record calculation: A randomized clinical trial.

OBJECTIVE: This study was performed to estimate the effectiveness of novel oral hygiene instruction (OHI) focusing on areas with deep periodontal pockets for reduction of periodontal inflammation. BACKGROUND DATA DISCUSSING THE PRESENT STATUS OF THE FIELD: Because stained areas on the plaque chart do not always correspond to the areas with deep periodontal pockets, conventional OHI based on O'Leary's plaque control record (PCR) often provides guidance inconsistent with the target area. METHODS: This randomized clinical trial involved two groups: (1) OHI based on the PCR limited in deep pocket sites (novel OHI group) and (2) OHI based on O'Leary's PCR (conventional OHI group). The unique PCR (aggressive target for PCR [agPCR]; only counting the plaque-stained areas with PD at ≥4 mm sites) for the novel OHI was calculate by dedicated expression program. The probing depth (PD), bleeding on probing (BOP), and periodontal inflamed surface area (PISA) were obtained at the baseline and 5 to 6 months later. RESULTS: The approximation curve with PISA before and after instruction indicated that the PISA converged to a lower value after instruction in the novel OHI group. The approximation curve with the improvement rate of the PISA and agPCR showed a positive correlation in the novel OHI group but no correlation in the conventional OHI group. CONCLUSION: Control of inflammation was more effective in the novel OHI group. These results suggest that this novel OHI technique using our developed application could be used as a strategy to improve the effectiveness of brushing instruction.

Identification method for dental alloy type using a cosine similarity program: A preliminary investigation.

Although dental evidence is frequently used for the identification of unidentified persons, information about the many types of alloys used in prosthetics is not utilized. If the type of alloy can be identified from a small amount of material, the scope of the search could be narrowed. In this experiment, a method was investigated for identifying the alloy type using 3 kinds of cutting points (a white point and 2 types of silicone points). Wavelength-dispersive X-ray spectroscopy (WDS) was used for elemental analysis. The elements were translated into multidimensional vectors, and the cosine similarity was calculated to compare vectors of the WDS results and vectors of the official data of alloys. According to the results, cosine similarity showed a concordance of more than 0.8. The developed program is expected to be useful as a method for identifying alloy types using only a small amount of grinding dust.

Intracellular stress caused by composite resins: An in vitro study using a bioluminescent antioxidant-responsive element reporter assay.

Context: Elucidating the effects of leachates from composite resins (CRs) on cells by examining the transcription level of detoxification genes and the antioxidant-responsive element (ARE), would be helpful in clinical practice. Aims: The aim of the study is to investigate the cytotoxicity of commercially available CRs, we used a reporter assay system to evaluate intracellular stress based on ARE-mediated transcription. Setting and Design: The study design was an in vitro study. Materials and Methods: Seven kinds of CRs were each placed in four-well plates to which culture medium was added and then light-cured. The prepared samples were used either immediately (sample A) or after incubation at 37°C for 24 h (sample B) in the subsequent ARE-luciferase reporter assay, in which HepG2 cells stably expressing an ARE-regulated luciferase reporter gene (HepG2-AD13 cells) were cultured for 6 h in culture media with the CR eluate (samples A or B) or without (control) (n = 4). In the cell viability assay, cell viability in various solutions with the same incubation time was confirmed by MTT assay (n = 4). Statistical analysis was performed using the paired t-test and one-way analysis of variance. Results: All CR solutions showed an increase in ARE activation rate; a CR with spherical nanofillers showed the highest ARE activation rate of 108.5-fold in sample A. Cell viability was not significantly reduced for any of the CRs in sample A. However, the CR-containing bisphenol A-glycidyl methacrylate (Bis-GMA) caused a significant decrease in cell viability in sample B. Conclusions: The intracellular stress in the viable cells differed among the CRs, depending on the type of monomer used. In particular, Bis-GMA-containing hydroxyl groups showed high cytotoxicity.

Potent and biostable inhibitors of the main protease of SARS-CoV-2.

Potent and biostable inhibitors of the main protease (Mpro) of SARS-CoV-2 were designed and synthesized based on an active hit compound 5h (2). Our strategy was based not only on the introduction of fluorine atoms into the inhibitor molecule for an increase of binding affinity for the pocket of Mpro and cell membrane permeability but also on the replacement of the digestible amide bond by a surrogate structure to increase the biostability of the compounds. Compound 3 is highly potent and blocks SARS-CoV-2 infection in vitro without a viral breakthrough. The derivatives, which contain a thioamide surrogate in the P2-P1 amide bond of these compounds (2 and 3), showed remarkably preferable pharmacokinetics in mice compared with the corresponding parent compounds. These data show that compounds 3 and its biostable derivative 4 are potential drugs for treating COVID-19 and that replacement of the digestible amide bond by its thioamide surrogate structure is an effective method.

Visualization of osteocalcin and bone morphogenetic protein 2 (BMP2) secretion from osteoblastic cells by bioluminescence imaging.

The secretions of osteocalcin and bone morphogenetic protein 2 (BMP2) from living osteoblastic cells were visualized for the first time using a method of video-rate bioluminescence imaging. The fusion proteins with Gaussia luciferase (GLase) for mouse osteocalcin and BMP2 (OC-GLase and BMP2-GLase, respectively) expressed in osteoblastic MC3T3-E1 cells were correctly processed and secreted. In the video images of exocytotic secretion, the luminescence spots of OC-GLase and BMP2-GLase disappeared rapidly and gradually, respectively, indicating different manners of these proteins in diffusion. Notably, a deletion mutant of BMP2 (Δ3BMP2-GLase) lacking three basic amino acid residues in the N-terminal region for binding to heparan sulfate showed rapidly disappearing luminescence spots. In our imaging conditions, the half-life of luminescence for the spots of Δ3BMP2-GLase (1.61 ± 0.20 s) was similar to that of OC-GLase (1.22 ± 0.14 s) but not to that of BMP2-GLase (4.31 ± 0.41 s). These results suggest that, in contrast to osteocalcin, the diffusion of BMP2 from cells occurred slowly after exocytosis. Thus, our bioluminescence imaging method is useful to study the diffusion properties of secreted proteins in exocytosis.

A novel identification method using perceptual degree of concordance of occlusal surfaces calculated by a Python program.

One of the important issues during the response to a mass disaster is the identification of victims. In this study, we verified the use of the occlusal morphology of molars for individual identification. The aim of this study was to establish a simple new method for identifying individuals from molar data. Using Python, we developed programming that included the perceptual Hash (pHash) function and the Hamming distance (HD) between antemortem data (AMD) and postmortem data (PMD). The AMD comprised 2,215 dental models. The PMD were selected from the AMD set and comprised 17 models from the same individual with changes over time. As a result, 16 PMD models (over 90%) were ranked in the top 5%. Although identification using only a single molar is difficult, there is the possibility of narrowing down victims' identity with high accuracy through verification using multiple teeth. This system is expected to be useful as a very simple method of identification.

Development of image analysis using Python: Relationship between matrix ratio of composite resin and curing temperature.

The aim of this study was to establish a measurement method for filler and matrix in cured resin composite (RC) using Python programming and to investigate the correlation between matrix ratio and curing temperature rise. Eight kinds of RCs were used. Backscattered electron images were taken for each cured specimen. Matrix and filler contents were calculated using Python programming with the K-means or area segmentation method. Volume measurement methods were assessed for comparison. Heat released during the polymerization reaction was measured. The matrix ratio was calculated without human intervention. Three specimens contained only inorganic filler, and other specimens contained multiple types of fillers. Almost the same values of the matrix ratio were obtained by programming and the volume measurement methods for specimens containing a single type of inorganic filler. Moreover, a strong correlation was found between the matrix ratio obtained by the programming method and curing temperature rise (R=0.9826).

Shrinkage characteristics of a novel lower contractile acrylic pattern resin.

Forming models and brazing parts, both of which require high accuracy, are greatly affected the polymerization shrinkage of pattern resin. In 2018, a lower-shrinkage autopolymerizing pattern resin (PRK) was introduced. In this work, we compared the rate of polymerization shrinkage between PRK with that of three autopolymerizing resins -GC Pattern Resin (GPR), Pi-Ku Plast (PIK), and Fixpeed (FIX)- as controls. The shrinkage percentages at 10 min were 7.26±0.88 for PRK, 10.78±2.28 for GPR, 8.03±1.08% for PIK, and 7.46±1.25 for FIX. The shrinkage of PRK was significantly lower than that of GPR. The lower-shrinkage autopolymerizing resin contains some multifunctional monomer and indicated that the amount of monomer was accordingly reduced from the result of polymer size and abundance ratio. Our results suggested that the monomer component and the polymer particle size were factors that contribute to reducing contraction of the resins.

Measurement of exothermic heat released during polymerization of a lightcuring composite resin: Comparison of light irradiation modes.

High-power light-curing units have emerged that reduce the time of procedures in dental clinical work. However, patients sometimes complain of pain during the polymerization of composite resin. In this experiment, we investigated how differences in light-curing mode affect the temperature rise during composite resin polymerization in vitro. Light-curing mode conditions were divided into four groups: 3 s in plasma mode (Plm3) and 5, 10, and 20 s in standard mode. The temperature curve under Plm3 exhibited a rapid increase during the first 3 s of light curing before reaching a maximum of around 55°C. In contrast, the temperature rose rapidly but less sharply for irradiation in each standard mode compared with Plm3. These results suggest that irradiation using a high-power mode increases the temperature at an excessively high rate, and this may raise concern about side effects on the pulp.

Leaching behaviors of computer-aided design/computer-aided manufacturing composite resin component elements immersed in water.

PURPOSE: Immersion tests in purified water were conducted to evaluate the leaching behaviors of filler elements contained in computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin. METHODS: Four commercial CAD/CAM resin composite blanks were tested: Shofu block HC 2 layer, Cerasmart, Katana Avencia block, and KZR-CAD HR Block 2. The specimens in the size of 10.0×12.0×2.0mm were immersed in a 50-mL conical tube containing 40mL of purified water, and then placed in a constant-temperature oven set at a temperature of 37, 60, 70, or 80°C and stored statically for 30 days. After storage, the concentrations of leached elements in the immersion solution were measured with an inductively coupled plasma atomic emission spectrometer. To characterize the surface of the specimen after the immersion test, secondary electron images were obtained. RESULTS: The immersion test resulted in the leaching of Si, the main component, from all materials tested. Some materials were found to have leached high amount of Ba or Sr in addition to Si, and remarkable surface degradation was observed. The amount of leached elements increased with increased immersion temperatures. CONCLUSIONS: Filler elements in CAD/CAM composite resins used in this study leached into purified water. The leached elements and its quantities greatly differed among materials and depend on the types of the oxides composing the filler. The amounts of leached elements varied in a temperature-dependent manner.

Postictal cardiovascular response predicts therapeutic efficacy of electroconvulsive therapy for depression.

Physiological parameters such as blood pressure (BP) and heart rate (HR) reflect autonomic response after seizure and may correlate with therapeutic efficacy in electroconvulsive therapy (ECT). However, the literature has been inconclusive with regard to the relationship between the effectiveness of ECT and physiological markers without atropine. In a consecutive sample of 24 patients with a drug-resistant major depressive episode who underwent modified sine or pulse wave ECT without atropine, the correlation was examined between BP and HR before, and 2 min after electrical stimulation and therapeutic efficacy on depressive symptoms. When mode of stimulation (sine wave or pulse wave) and baseline Hamilton Rating Scale for Depression (HRSD) were controlled for, postictal diastolic BP, systolic BP, HR and rate pressure product (RPP) were all found to be significant predictors of post-treatment HRSD. When these predictors were entered into stepwise regression, both postictal systolic BP and HR remained as significant predictors. The higher these postical physiological parameters, the more effective the course of ECT. It may be useful to examine such sensitive physiological parameters as BP, HR or RPP to determine effective or non-effective electrical seizure.

Postictal suppression correlates with therapeutic efficacy for depression in bilateral sine and pulse wave electroconvulsive therapy.

Ictal electroencephalography (EEG) parameters in electroconvulsive therapy (ECT) for depression reportedly correlate with therapeutic response and stimulus dosage, particularly in right unilateral (RUL) ECT. The authors examined ictal EEG parameters as predictors of therapeutic effectiveness in bilateral (BL) sine and pulse wave ECT. A total of 30 consecutive depressed inpatients who had not responded to standard pharmacotherapy were treated using BL ECT given in either sine or pulse wave mode. Ictal EEG parameters (e.g. regularity, postictal suppression) were manually rated by three trained psychiatrists. Polyspike phase duration was significantly longer in sine wave ECT than in pulse wave ECT. Postictal suppression emerged as the only significant predictor of therapeutic outcome when baseline Hamilton Rating Scale for Depression and mode of stimulation were controlled for. Postictal suppression appears to offer a useful predictor of clinical outcome of depression in BL ECT. No EEG parameters were found to be differentially predictive between sine and pulse wave ECT.

Memory, attention, and executive functions before and after sine and pulse wave electroconvulsive therapies for treatment-resistant major depression.

OBJECTIVE: Studies of the cognitive effects of electroconvulsive therapy (ECT) have resulted in controversial findings up to now, partly because researchers and reviewers have not always made a clear distinction among various aspects of cognition and because there are many parameters involved in the administration of ECT that have a potential impact on cognition. The present study focused on the impact of sine and pulse waveforms on anterograde memory and nonmemory cognitive functions. METHODS: We assigned 18 patients with unipolar major depression or bipolar I or II disorder, most recent episode depressed, to receive sine wave or pulse wave ECT and assessed their cognitive function before and after ECT, using a neuropsychologic test battery that measured anterograde memory, attention, and executive functions. Outcomes were measured, on average, 8.2 days after the last ECT session. RESULTS: Both waveforms were equally effective in alleviating depression. Those who received sine wave ECT showed statistically significant deterioration in attention and executive tasks, such as the Stroop test, which measures selective attention (P = 0.02), and the dual task, which taps divided attention (P = 0.01). On the other hand, those who received pulse wave ECT improved to a significant degree in certain memory tasks, such as visual memory (P = 0.01) and general memory (P = 0.01) of the Wechsler Memory Scale-Revised (WMS-R), as well as in the dual task (P = 0.01). The between-group comparison revealed robust superiority of the pulse wave over the sine wave in terms of the dual task (P = 0.004). CONCLUSIONS: Anterograde memory improved to a statistically significant or nonsignificant degree at 1 week post-ECT in comparison with pre-ECT regardless of waveforms. Attention/executive functions tended to deteriorate with sine wave ECT but improved with pulse wave ECT.