Impact of Direct Observation on Hand Hygiene Compliance in a Dental University Hospital: A Retrospective Cohort Study.

Introduction Hand hygiene is crucial for preventing healthcare-associated infections in dental settings. Despite its importance, the hand hygiene compliance rates remain unclear, particularly in dental university hospitals where teaching, research, and clinical practice intersect. This study aimed to establish a baseline of hand hygiene compliance rates in a dental university hospital, evaluate the effectiveness of direct observation in improving compliance, and compare practices among different categories of healthcare workers. Materials and methods This retrospective cohort study was conducted at Kanagawa Dental University Hospital from April 2022 to March 2023. The design included four blinded direct observations to establish baseline compliance rates, followed by educational training and four unannounced explicit observations. Compliance was assessed based on the World Health Organization's "Your 5 Moments for Hand Hygiene: Dental Care," adapted for dental outpatient services. The study focused on hand hygiene using alcohol-based hand sanitizers, and compliance rates were calculated for dentists, dental hygienists, dental assistants, and trainee dentists. Monthly consumption of hand sanitizer per patient was tracked from January 2019 as a secondary measure. Statistical analysis included Fisher's exact test, unpaired t-tests, and analysis of variance (ANOVA). Results The baseline hand hygiene compliance rate was low at 15.6%, with the highest compliance (25.0%) for "After touching patient surroundings." Post-intervention, the overall compliance rate increased significantly to 36.0% (p < 0.001). Significant improvements were observed in moments "After body fluid exposure risk" (11.1% to 31.3%, p = 0.004), "After touching a patient" (12.0% to 52.9%, p = 0.006), and "After touching patient surroundings" (25.0% to 73.3%, p = 0.001). Dental hygienists, assistants, and trainee dentists showed significant increases in hand hygiene compliance, while dentists did not. Hand sanitizer consumption increased significantly from 2019 (2.38 ± 0.29 mL per patient) to 2020 (3.47 ± 0.49 mL, p < 0.001) and remained elevated through 2023. Conclusions This study revealed low baseline hand hygiene compliance in a dental university hospital setting. While direct observation and education led to significant short-term improvements, especially among allied health professionals, the disconnect between observed compliance rates and hand sanitizer consumption suggests these changes may not represent sustainable behavioral shifts. The varying improvement rates among different healthcare workers and the challenges in maintaining long-term adherence highlight the need for tailored, continuous interventions in dental education and practice settings to enhance hand hygiene compliance.

General Anesthesia for Patients With Cyclic Vomiting Syndrome and Obesity: A Case Report.

Cyclic vomiting syndrome (CVS) is a chronic digestive disorder characterized by recurrent episodes of severe nausea and vomiting. The perioperative management of patients with CVS undergoing general anesthesia is challenging, especially when combined with obesity. This case report describes the successful management of a patient with CVS and obesity who underwent dental surgery under general anesthesia. A 21-year-old woman with CVS, obesity (body mass index, 35), and intellectual disability was scheduled for tooth extraction and composite resin restoration under general anesthesia. The patient was diagnosed with CVS at the age of 20 years with frequent vomiting attacks requiring hospitalization. Surgery was scheduled during the CVS remission to reduce the risk of perioperative vomiting. Preoperative laboratory test results were normal, including serum adrenocorticotropic hormone (ACTH), anti-diuretic hormone (ADH), and cortisol levels. General anesthesia was induced using remifentanil and propofol. Nasal endotracheal intubation was performed after rocuronium administration. Local anesthesia (2% lidocaine with 1:80,000 epinephrine) was used for all dental procedures. Postoperatively, midazolam was administered to control agitation. No postoperative vomiting occurred. Serum ACTH, ADH, and cortisol levels showed no significant changes before and after anesthesia, suggesting that hypothalamic-pituitary-adrenal (HPA) axis activation due to surgical stress did not occur. This case highlights the importance of careful perioperative planning and monitoring stress-related hormone levels in patients with CVS or obesity. An anesthetic approach using midazolam may effectively suppress HPA axis activation and prevent postoperative vomiting.

Effect of Dental Local Anesthetics on Reactive Oxygen Species: An In Vitro Study.

Introduction Oxidative stress, an imbalance between reactive oxygen species (ROS) production and antioxidant defenses, plays an important role in various dental diseases. Local anesthetics are frequently used in dentistry. The potential antioxidant activity of dental local anesthetics can contribute to dental practice. Therefore, this study aimed to investigate the ROS-scavenging activities of three commonly used dental local anesthetics, lidocaine, prilocaine, and articaine, focusing on their effects on hydroxyl radicals (HO•) and superoxide anions (O2 •-). Materials and methods The electron spin resonance (ESR) spin-trapping technique was employed to specifically measure the ROS-scavenging activities of these local anesthetics at varying concentrations. Results Lidocaine, prilocaine, and articaine exhibited concentration-dependent HO•-scavenging activities, with IC50 values of 0.029%, 0.019%, and 0.014%, respectively. Lidocaine and prilocaine showed concentration-dependent O2 •--scavenging activity, with IC50 values of 0.033% and 0.057%, respectively. However, articaine did not scavenge O2 •-. Conclusions The proactive use of dental local anesthetics may mitigate oxidative injury and inflammatory damage through direct ROS scavenging. However, further research is needed to elucidate the specific mechanisms underlying the antioxidant effects of these dental local anesthetics and their potential impact on the dental diseases associated with oxidative stress.

Anti-inflammatory potential of remimazolam: A laboratory and clinical investigation.

BACKGROUND: Anesthetic agents, particularly intravenous anesthetics, may affect immune function and tumorigenic factors. We herein investigated whether the anti-inflammatory effects of anesthetic agents are attributed to their antioxidant properties. The antioxidant and anti-inflammatory effects of remimazolam, a new anesthetic, remain unclear. We hypothesized that remimazolam exerts anti-inflammatory effects due to its antioxidant properties, which may affect the postoperative inflammatory response. This retrospective clinical study examined this hypothesis using laboratory and clinical approaches. METHODS: The antioxidant effects of remimazolam and dexmedetomidine were assessed by electron spin resonance (ESR) spectroscopy, and postoperative inflammatory responses were compared in 143 patients who underwent transcatheter aortic valve replacement at Kindai University Hospital between April 2021 and December 2022. The primary endpoint was the presence or absence of the antioxidant effects of the anesthetics themselves using ESR. RESULTS: Remimazolam at clinical concentrations exerted antioxidant effects, whereas dexmedetomidine did not. Increases in C-reactive protein (CRP) levels on POD3 from preoperative values were significantly smaller in the remimazolam group than in the dexmedetomidine group (1.33 ± 1.29 vs. 2.17 ± 1.84, p = .014). CONCLUSIONS: Remimazolam exerted stronger anti-inflammatory effects than dexmedetomidine, and these effects were enhanced by its antioxidant properties, which may have affected postoperative CRP production.

Analysis of Sedation Accident Records Available in the Japan Council for Quality Health Care Public Database.

OBJECTIVE: Medical accidents occur frequently. However, only a few studies have been conducted on sedation-related medical accidents. This study aimed to classify sedation accidents and analyze their causes using the (Patient-management Software Hardware Environment Livewear (P-mSHELL) model. METHODS: The Japan Council for Quality Health Care database on medical accidents was used. Sedation accidents that occurred during procedures between January 2010 and June 2022 were included. After examining the accident details for several variables, the accident factors were classified by factors in the P-mSHELL model, and statistical analyses, including multivariate analysis of each factor and outcome (presence or absence of residual disability), were conducted. RESULTS: Regarding the influence of the P-mSHELL factors on outcome, P factor (odds ratio = 6.347, 95% confidence interval = 2.000, 20.144) was a factor for having disability. There was a significant association between outcome and accident timing (that is, preoperative, intraoperative, or postoperative; p =0.01). No significant association was found between the outcomes and types of drugs used (p =1, 0.722, 0.594); however, there was a significant association between the incidence of respiratory depression and multiple drug use (p <0.001). CONCLUSIONS: To prevent sedation accidents, it is important to monitor patients throughout the perioperative period. However, it is especially important to know the patient's condition in advance, and strict postoperative management is essential, especially for high-risk patients, to prevent serious accidents.

Survey on the Awareness of the Use of Oropharyngeal Throat Packs in Dental Anesthesia: An International Online Survey.

INTRODUCTION: Oropharyngeal throat packs (OPTPs) are frequently used to administer general anesthesia during oral surgery and dental procedures. However, the use of OPTPs has remained controversial, with concerns about their effectiveness, the potential for falling short of expectations, and the inherent risk of serious oversight in removing them. This study aimed to assess the awareness of dental anesthesiologists in the United States of America (USA) and Japan regarding the use of OPTPs. METHODS: An online questionnaire was distributed to 41 dental anesthesia education facilities in May 2023 and responses were obtained from 32 facilities. RESULTS: The responses to the questionnaire indicated that dental anesthesiologists in both the USA and Japan believe that using OPTPs during general anesthesia with airway securement is of significant importance, albeit with varying primary purposes for their application. In contrast, notable disparities were observed between the USA and Japan regarding the perceived importance and routine use of OPTPs during open-airway general anesthesia. In both countries, there is a common understanding that the residual risks of OPTPs are severe and that multiple preventive procedures are required. CONCLUSIONS:  The present study showed that dental anesthesiologists in the USA and Japan believed that the use of OPTPs was generally necessary for dental anesthesia. However, there was a difference in awareness between Japan and the USA regarding the importance of OPTPs for open-airway general anesthesia. Therefore, there should be a consensus among dental anesthesiologists in Japan and the USA on using OPTPs during open-airway general anesthesia in the near future.

Comparison of Lidocaine and Mepivacaine for Variation in Regional Tissue Oxygenation in Stellate Ganglion Block: A Randomized, Double-Blind, Crossover Trial.

Introduction This prospective, randomized, double-blind, crossover trial aimed to investigate the effect of different types of local anesthetics on regional tissue blood oxygenation on the stellate ganglion block (SGB). Methods Twenty eligible patients were recruited for this study; 16 of whom were allocated to the study protocol. Participants were randomized into one of the two crossover sequences: 1% lidocaine hydrochloride or 1% mepivacaine hydrochloride, and received SGBs with 6 mL of any one of the local anesthetics, followed by a washout period of more than 24 hours, and then received SGBs by substituting the two local anesthetics. The tissue oxygenation index (TOI) in the skin near the mental foramen on the blocked side was recorded using near-infrared spectroscopy at 15 minutes after the local anesthetic injection. Results One participant did not complete the study. As such, variation in regional tissue oxygenation was compared between the 15 participants. There was no difference in the increase in regional tissue blood flow or tissue oxygenation after SGB between the patients who were given lidocaine and the ones who were given mepivacaine; however, the kinetics of the increase in regional tissue oxygenation were significantly faster with mepivacaine than with lidocaine. Conclusions Different types of local anesthetics do not affect the intensity of the increase in regional tissue oxygenation after SGB, but they do affect the kinetics of the increase. These differences in local anesthetics may affect how patients feel after receiving SGB, the duration of SGB effects, and the frequency of adverse events associated with SGB.

Carbamazepine-Induced Systemic Lupus Erythematosus in a Patient With Idiopathic Trigeminal Neuralgia: A Case Report.

A 50-year-old woman presented with a mandibular second molar and facial pain and was diagnosed with idiopathic trigeminal neuralgia. Carbamazepine (CBZ) was initiated at 300 mg/day, successfully relieving the pain. However, on the 8th day of CBZ treatment, the patient developed symptoms resembling those of systemic lupus erythematosus with malaise, nausea, and facial erythema. CBZ was immediately discontinued. Subsequently, she experienced numbness in both lower limbs and mild fever, which resolved within a few days. Laboratory tests revealed leukopenia (2.8 × 103/µL), elevated C-reactive protein levels (0.46 mg/dL), and the presence of antinuclear antibodies (ANA) and anti-Sjögren's syndrome-related antigen A antibodies. The clinical course suggested CBZ-induced drug-induced lupus erythematosus (DILE). This case highlights the possibility of DILE onset even after short-term CBZ treatment, the importance of prompt discontinuation of the causative drug in patients suspected of DILE, and the conduct of ANA testing in diagnosing DILE.

Influence of the amount of saliva deposition and time elapsed after deposition on bite mark analysis.

Bite mark analysis is among the most interesting research fields in forensic odontology; however, it is limited by its dependence on the employed method as well as assessor subjectivity, particularly when using morphological analysis or DNA profiling. These limitations are due to differences in DNA collected from saliva adhering to a living or inanimate body, as well as differences in exocrine fluid secretion and deposition amount among individuals. This study aimed to analyze the effectiveness of DNA profiling when there are differences in the amount of saliva adhering to a living body and when time has elapsed since deposition. Most allele peaks could be identified in 1 µl of saliva, even 9 h after saliva deposition and examination. Consistent results were obtained following saliva deposition in an individual who had engaged in up to 9 h of free activity. The results of this study demonstrate the validity and reliability of DNA profiling for bite mark analysis and are extremely important as they can demonstrate the usefulness of the little information left by a suspect on a victim's body.

Effectiveness of curcumin-based antimicrobial photodynamic therapy against Staphylococcus aureus.

PURPOSE: This study investigated the effectiveness of curcumin-based antimicrobial photodynamic therapy (aPDT) against Staphylococcus aureus (S. aureus), the causative agent of ventilator-associated pneumonia. METHODS: Curcumin was added to S. aureus culture medium at concentrations of 25, 2.5, and 0.25 µM. After 60 min (20-25°C), each culture was irradiated for 1 and 3 min, and viable bacteria were counted. Curcumin (25 µM) was also added to a bacterial suspension with D-mannitol and sodium azide; microbial counts were determined after irradiation for 3 min. RESULTS: S. aureus was significantly reduced in the 1-min (P = 0.043) and 3-min (P = 0.011) irradiation groups in comparison to the 0-min irradiation group with 25 µM curcumin. No significant differences were observed between the curcumin alone group and the curcumin plus D-mannitol or sodium azide group. CONCLUSION: The findings of this study indicate that prolonged exposure (≥1 min) of S. aureus to LED in 25 µM curcumin solution induces cell wall injury. Curcumin-based aPDT as an adjunct to conventional oral care, employing existing dentistry equipment, offers a promising approach that does not rely on antimicrobial drugs or allows the emergence of resistant bacterial strains. This suggests its potential role in future strategies aimed at preventing ventilator-associated pneumonia.

Safety of COVID-19 vaccine delivery by dentists: An observational cohort study.

Background/purpose: Although many coronavirus disease 2019 (COVID-19) vaccine injections have been administered worldwide, the safety of this practice remains unclear. This study aimed to compare the rates of complications associated with COVID-19 vaccines administered by dentists with those of vaccines administered by nurses. This study aimed to evaluate the safety of a vaccination program delivered by dentists. Materials and methods: This observational cohort study included 537 recipients of the second dose of the Pfizer COVID-19 vaccine, delivered as an intramuscular injection to the upper arm deltoid muscle by dentists or nurses at the study site. Vaccine recipients were divided into two groups according to the vaccination administrator (dentist vs. nurse groups). The rates of complications associated with intramuscular injection technique (numbness in the hand or arm at the time of the injection, vasovagal reflex at the time of the injection, vaccine-related shoulder injury, and prolonged numbness) were examined. Results: A total of 125 vaccine recipients were included (nurse group, n = 84; dentist group, n = 41). The overall incidence rate of complications was lower in the dentist group (2.4%; 1/41) than in the nurse group (8.3%; 7/84). However, this difference was not statistically significant (P = 0.3). Conclusion: This study suggests that the safety of COVID-19 vaccine administration is comparable between dentists and nurses.

The Impact of COVID-19 on Dental Anesthesiologists: An Online Survey of Board-Certified Dental Anesthesiology Specialists of the Japanese Dental Society of Anesthesiology.

OBJECTIVE: The impact of the COVID-19 pandemic on dental anesthesiologists has not been examined. This study aimed to determine how the COVID-19 pandemic affected Japanese dental anesthesiologists' professional lives. METHODS: An online questionnaire related to the effects of COVID-19 on dental anesthesiologists' professional lives was emailed to 351 board-certified dental anesthesiology specialists from the Japanese Dental Society of Anesthesiology. The endpoints of this study were changes in income and job satisfaction as a dental anesthesiologist from 2019 prior to the COVID-19 pandemic. RESULTS: A total of 141 dental anesthesiologists participated in the survey. Most respondents reported no change in income relative to 2019 for 2020 or 2021. Significantly more dental anesthesiologists reported income decreases relative to 2019 for 2020 (39%) vs 2021 (21.3%; P = .001). Very few dental anesthesiologists reported income increases relative to 2019 for 2020 (2.1%) vs 2021 (15.6%; P < .001). Job satisfaction as a dental anesthesiologist remained unchanged for all 3 years. CONCLUSION: Even though many Japanese dental anesthesiologist specialists lost income because of COVID-19, they maintained their job satisfaction.

A method for estimating time since death through analysis of substances deposited on the surface of dental enamel in a body immersed in freshwater.

Estimating the elapsed time after death of a corpse immersed in freshwater is often challenging owing to body temperature changes and the degree of postmortem lividity, and the tissues used for this assessment deteriorate drastically as the postmortem period progresses. In this study, assuming a corpse was immersed in freshwater, we analyzed changes in the amount of deposits on the enamel surface of teeth since the time of immersion using an electron probe microanalyzer. We calculated a regression equation for estimating the time of immersion in water (the time after death). We considered this approach would be useful to estimate the time after death even in rotting and skeletonized corpses from which only limited information could be obtained. This study was undertaken according to a previously reported method that used a regression equation for estimating the time after death of bodies found in a seawater area.

Direct Mechanical Stimulation Mediates Cell-to-Cell Interactions in Cultured Trigeminal Ganglion Cells.

Trigeminal neuralgia occurs in the orofacial region, characteristically causing pain that feels like a transient electric shock. Some histopathological studies have reported that trigeminal neuralgia is caused by mechanical compression of the demyelinated trigeminal nerve; the pathophysiological mechanism behind this phenomenon remains to be clarified, however. Cell-cell interactions have also been reported to be involved in the development and modulation of some types of neuropathic pain. The purpose of this study was to investigate the potential contribution of cell-cell interactions to trigeminal neuralgia by measuring intracellular free Ca2+ concentrations ([Ca2+]i) in primary cultured trigeminal ganglion (TG) cells. Direct mechanical stimulation of TG cells induced an increase in [Ca2+]i in both neuronal and non-neuronal cells, such as glial cells. Moreover, this increase was stimulus intensity-dependent and non-desensitizing. Direct mechanical stimulation increased [Ca2+]i in neighboring cells as well, and this increase was inhibited by application of carbamazepine. These results indicate that direct mechanical stimulation affects Ca2+ signaling. Trigeminal ganglion cells establish intercellular networks between themselves, suggesting that this is involved in the development and generation of trigeminal neuralgia.

Piezo1-pannexin-1-P2X3 axis in odontoblasts and neurons mediates sensory transduction in dentinal sensitivity.

According to the "hydrodynamic theory," dentinal pain or sensitivity is caused by dentinal fluid movement following the application of various stimuli to the dentin surface. Recent convergent evidence in Vitro has shown that plasma membrane deformation, mimicking dentinal fluid movement, activates mechanosensitive transient receptor potential (TRP)/Piezo channels in odontoblasts, with the Ca2+ signal eliciting the release of ATP from pannexin-1 (PANX-1). The released ATP activates the P2X3 receptor, which generates and propagates action potentials in the intradental Aδ afferent neurons. Thus, odontoblasts act as sensory receptor cells, and odontoblast-neuron signal communication established by the TRP/Piezo channel-PANX-1-P2X3 receptor complex may describe the mechanism of the sensory transduction sequence for dentinal sensitivity. To determine whether odontoblast-neuron communication and odontoblasts acting as sensory receptors are essential for generating dentinal pain, we evaluated nociceptive scores by analyzing behaviors evoked by dentinal sensitivity in conscious Wistar rats and Cre-mediated transgenic mouse models. In the dentin-exposed group, treatment with a bonding agent on the dentin surface, as well as systemic administration of A-317491 (P2X3 receptor antagonist), mefloquine and 10PANX (non-selective and selective PANX-1 antagonists), GsMTx-4 (selective Piezo1 channel antagonist), and HC-030031 (selective TRPA1 channel antagonist), but not HC-070 (selective TRPC5 channel antagonist), significantly reduced nociceptive scores following cold water (0.1 ml) stimulation of the exposed dentin surface of the incisors compared to the scores of rats without local or systemic treatment. When we applied cold water stimulation to the exposed dentin surface of the lower first molar, nociceptive scores in the rats with systemic administration of A-317491, 10PANX, and GsMTx-4 were significantly reduced compared to those in the rats without systemic treatment. Dentin-exposed mice, with somatic odontoblast-specific depletion, also showed significant reduction in the nociceptive scores compared to those of Cre-mediated transgenic mice, which did not show any type of cell deletion, including odontoblasts. In the odontoblast-eliminated mice, P2X3 receptor-positive A-neurons were morphologically intact. These results indicate that neurotransmission between odontoblasts and neurons mediated by the Piezo1/TRPA1-pannexin-1-P2X3 receptor axis is necessary for the development of dentinal pain. In addition, odontoblasts are necessary for sensory transduction to generate dentinal sensitivity as mechanosensory receptor cells.

Impact of Stellate Ganglion Block on Tissue Blood Flow/Oxygenation and Postoperative Mandibular Nerve Hypoesthesia: A Cohort Study.

PURPOSE: Although a stellate ganglion block (SGB) increases tissue blood flow in the mandibular region, the change in tissue oxygenation after SGB and therapeutic effect of SGB for postoperative mandibular nerve hypoesthesia remain to be established. The study aim was to measure the change in tissue oxygenation in the mandibular region after SGB. METHODS: To determine the variation in tissue oxygenation in the mandibular region, the tissue oxygen index (TOI; percentage of oxygenated hemoglobin in the total hemoglobin) was measured at the skin near the mental foramen bilaterally, at the primary site of unilateral SGB, achieved using 6 mL of 1% lidocaine hydrochloride, for the treatment of bilateral postoperative mandibular nerve injury. The primary outcome of this study is the temporal variation in TOI after SGB (0.5, 1, 5, 10, 15, 20, and 25 minutes after SGB), and the control group in this study is the TOI at the end of SGB injection (0 minute). All data are expressed as the mean ± standard deviation and 95% confidence interval (CI). Repeated-measures analysis of variance with Dunnett's test was used to determine parametric statistical significance. A P-value <.05 was considered statistically significant. RESULTS: Thirteen patients were enrolled in this study. On both the blocked and contralateral side, the TOI was significantly increased compared to that before SGB (ΔTOI at 15 minute after SGB, 5.87 ± 2.89%, P < .001, 95% CI: 4.122 to 7.617% in the blocked side, 1.88 ± 2.73%, P = .005, 95% CI: 1.877 to 2.725% in the contralateral side). CONCLUSIONS: Unilateral SGB using 6 mL of 1% lidocaine hydrochloride results in an increase in tissue oxygenation in the mandibular region. Based on these findings, we hypothesize that a series of SGBs may contribute to a more rapid recovery of postoperative trigeminal nerve injury.

Plasma Membrane Ca2+-ATPase in Rat and Human Odontoblasts Mediates Dentin Mineralization.

Intracellular Ca2+ signaling engendered by Ca2+ influx and mobilization in odontoblasts is critical for dentinogenesis induced by multiple stimuli at the dentin surface. Increased Ca2+ is exported by the Na+-Ca2+ exchanger (NCX) and plasma membrane Ca2+-ATPase (PMCA) to maintain Ca2+ homeostasis. We previously demonstrated a functional coupling between Ca2+ extrusion by NCX and its influx through transient receptor potential channels in odontoblasts. Although the presence of PMCA in odontoblasts has been previously described, steady-state levels of mRNA-encoding PMCA subtypes, pharmacological properties, and other cellular functions remain unclear. Thus, we investigated PMCA mRNA levels and their contribution to mineralization under physiological conditions. We also examined the role of PMCA in the Ca2+ extrusion pathway during hypotonic and alkaline stimulation-induced increases in intracellular free Ca2+ concentration ([Ca2+]i). We performed RT-PCR and mineralization assays in human odontoblasts. [Ca2+]i was measured using fura-2 fluorescence measurements in odontoblasts isolated from newborn Wistar rat incisor teeth and human odontoblasts. We detected mRNA encoding PMCA1-4 in human odontoblasts. The application of hypotonic or alkaline solutions transiently increased [Ca2+]i in odontoblasts in both rat and human odontoblasts. The Ca2+ extrusion efficiency during the hypotonic or alkaline solution-induced [Ca2+]i increase was decreased by PMCA inhibitors in both cell types. Alizarin red and von Kossa staining showed that PMCA inhibition suppressed mineralization. In addition, alkaline stimulation (not hypotonic stimulation) to human odontoblasts upregulated the mRNA levels of dentin matrix protein-1 (DMP-1) and dentin sialophosphoprotein (DSPP). The PMCA inhibitor did not affect DMP-1 or DSPP mRNA levels at pH 7.4-8.8 and under isotonic and hypotonic conditions, respectively. We also observed PMCA1 immunoreactivity using immunofluorescence analysis. These findings indicate that PMCA participates in maintaining [Ca2+]i homeostasis in odontoblasts by Ca2+ extrusion following [Ca2+]i elevation. In addition, PMCA participates in dentinogenesis by transporting Ca2+ to the mineralizing front (which is independent of non-collagenous dentin matrix protein secretion) under physiological and pathological conditions following mechanical stimulation by hydrodynamic force inside dentinal tubules, or direct alkaline stimulation by the application of high-pH dental materials.

Functional Coupling between the P2X7 Receptor and Pannexin-1 Channel in Rat Trigeminal Ganglion Neurons.

The ionotropic P2X receptor, P2X7, is believed to regulate and/or generate nociceptive pain, and pain in several neuropathological diseases. Although there is a known relationship between P2X7 receptor activity and pain sensing, its detailed functional properties in trigeminal ganglion (TG) neurons remains unclear. We examined the electrophysiological and pharmacological characteristics of the P2X7 receptor and its functional coupling with other P2X receptors and pannexin-1 (PANX1) channels in primary cultured rat TG neurons, using whole-cell patch-clamp recordings. Application of ATP and Bz-ATP induced long-lasting biphasic inward currents that were more sensitive to extracellular Bz-ATP than ATP, indicating that the current was carried by P2X7 receptors. While the biphasic current densities of the first and second components were increased by Bz-ATP in a concentration dependent manner; current duration was only affected in the second component. These currents were significantly inhibited by P2X7 receptor antagonists, while only the second component was inhibited by P2X1, 3, and 4 receptor antagonists, PANX1 channel inhibitors, and extracellular ATPase. Taken together, our data suggests that autocrine or paracrine signaling via the P2X7-PANX1-P2X receptor/channel complex may play important roles in several pain sensing pathways via long-lasting neuronal activity driven by extracellular high-concentration ATP following tissue damage in the orofacial area.

Survey of dental hygienists' and dental hygienist students' attitudes towards body identification tasks of unidentified human remains.

OBJECTIVE: Dental findings are used to identify unidentified human remains. The post-mortem records, necessary for the appraisal of dental findings, are created by the dentist; however, a system for dental hygienists specializing in these tasks to utilize has not yet been considered. METHODS: This study was directed at both students at a dental hygienist school and dental hygienists. We conducted an awareness survey on their willingness to participate in these tasks, as well as the need for education regarding body identification tasks. RESULTS: The results showed that students and dental hygienists are highly interested in body identification tasks and highly motivated to participate. Numerous participants preferred to take courses regarding basic knowledge in both lecture and practical training settings to acquire the knowledge necessary for performing these tasks. CONCLUSIONS: It is necessary to consider the curriculum content and timing of lectures and practices related to body identification tasks. Participation limited to the creation of post-mortem records, except for the creation of antemortem records requiring diagnosis and treatment knowledge and the matching task of antemortem records and post-mortem records, should be considered to prevent the tasks of dental hygienists from excessively expanding. If dental hygienists train properly, intraoral findings records can be drawn up by a team consisting of 1 dentist and 1 dental hygienist. Therefore, it is expected that the use of forensic dental identification, which is a relatively quick identification method, will be further improved.