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An anterograde biocytin and a retrograde WGA-colloidal gold study in the rat can provide information about reciprocal communication pathways between the red nucleus and the trigeminal sensory complex. No terminals were found within the trigeminal motor nucleus, in contrast with the facial motor nucleus. A dense terminal field was observed in the parvicellular reticular formation ventrally to the trigeminal motor nucleus. The parvicellular area may be important for the control of jaw movements by rubrotrigeminal inputs. On the other hand, the contralateral rostral parvicellular part of the red nucleus receives terminals from the same zone in the rostral part of the trigeminal sensory complex, where retrogradely labelled neurones were found after tracer injections into the red nucleus. Such relationships could be part of a control loop for somatosensory information from the orofacial area.

Transcutaneous cranial electrical stimulation with Limoge's currents has been shown to facilitate anesthesia/analgesia in surgical patients. However, the neurobiologic substrate of this effect remains unknown. The present study was designed to analyze the influence of transcranial electrical stimulation (TCES) on halothane requirements in rats and the contribution of the central endogenous opioid, alpha 2-adrenergic and 5-hydroxytryptamine (5-HT1 and 5-HT2) serotonergic systems to this effect. The influence of TCES on the MAC of halothane (MACH) and its reversibility by a subcutaneous 2 mg/kg naloxone injection were first determined in 20 rats using a randomized blinded protocol. MACH was decreased markedly in stimulated animals (TCES, n = 10) in comparison with sham-operated nonstimulated rats (controls, n = 10): MACH = 0.60 +/- 0.15, mean +/- SD, versus 1.07 +/- 0.05 vol%, P less than 0.001. In TCES animals, naloxone administration restored MACH values to the levels of controls but failed to affect MACH in controls. The influence of the duration of TCES applied prior to MACH determination was further investigated in 30 animals. The magnitude of MACH reduction was significantly increased with the cumulative duration of stimulation. For each duration of stimulation tested, administration of a 5-micrograms intracerebroventricular (icv) dose of the enkephalinase inhibitor thiorphan significantly enhanced TCES effects (P less than 0.05). Finally, the icv administration of a 15-micrograms naloxone dose appeared to reverse completely the MACH reduction elicited by TCES (n = 8, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Background: Considering the inter-relationship between Diabetes Mellitus (DM) and oral tissues, assessment of oral health status in relation to glycemic control might be informative about the disease condition, which might be pivotal to appropriate management and ultimately improve life satisfaction. This study therefore aimed to assess the pattern of self-reported diabetes related oral conditions and oral health-related quality of life (OHRQoL) among patients with DM at the University College Hospital (UCH), Ibadan, Nigeria. Materials and methods: A cross- sectional study using an interviewer administered questionnaire was conducted among in- and out- patients being managed for DM by the Endocrinology unit of the hospital. Data collected included bio-data, medical history, self-reported oral conditions and dental service utilisation. The impact of oral health related quality of life was measured using OHIP-14. Oral examination was done to assess oral mucosal lesions and their oral hygiene status. Data was analysed using SPSS 21. Results: Eighty-four patients with diabetes consisting 23 (27%) in-patients and 61 (63%) out-patients were enrolled. Males were 26(31%) and females 58(69%); their ages ranged from 22 to 88 years with a mean of 60.9 ± 12.8 years. Most (67%) of the participants had one or more self-reported oral complaints, dryness (20.4%) being the most common and bad breath (4.6%) as the least reported. Poor glycemic level was found to be higher among the in-patients (82%) with random blood glucose > 200 mg/dL during admission, compared to the out-patient participants (51%) who had fasting plasma glucose > 110 mg/dL. Their oral hygiene status was assessed using simplified oral hygiene index and documented as fair (65%), poor (25%) and good (10%). About two-thirds (61%) had ever visited a dentist, majorly due to toothache. Only the pain (21.9%) and physical disability (26.3%) components of OHIP-14 were mainly found to affect the participants' OHRQOL. Conclusions: This study found high rate of self- reported DM related oral conditions notably oral dryness, and periodontal diseases particularly as teeth mobility and spontaneous exfoliation. Nonetheless, most of the study participants had fair OHRQoL while its physical pain, functional limitation and psychological disability components were most reported. [ABSTRACT FROM AUTHOR]

Animals interact with their environment through mechanically active, mobile sensors. The efficient use of these sensory organs implies the ability to track their position; otherwise, perceptual stability or prehension would be profoundly impeded. The nervous system may keep track of the position of a sensorimotor organ via two complementary feedback mechanisms--peripheral reafference (external, sensory feedback) and efference copy (internal feedback). Yet, the potential contributions of these mechanisms remain largely unexplored. By training male rats to place one of their vibrissae within a predetermined angular range without contact, a task that depends on knowledge of vibrissa position relative to their face, we found that peripheral reafference is not required. The presence of motor cortex is not required either, except in the absence of peripheral reafference to maintain motor stability. Finally, the red nucleus, which receives descending inputs from motor cortex and cerebellum and projects to facial motoneurons, is critically involved in the execution of the vibrissa positioning task. All told, our results point toward the existence of an internal model that requires either peripheral reafference or motor cortex to optimally drive voluntary motion. [ABSTRACT FROM AUTHOR]

Wisdom tooth extraction is one of the most commonly performed procedures by oral maxillofacial surgeons. Delayed-onset infection (DOI) is a rare complication of wisdom tooth extraction, and it occurs ~1–4 weeks after the extraction. In the present study, risk factors for DOI were investigated by retrospectively analyzing the cases of 1400 mandibular wisdom tooth extractions performed at Kagawa University Hospital from April 2015 to June 2022. Inclusion criteria were patients aged >15 years with a wisdom tooth extraction per our procedure. The exclusion criteria were patients with insufficient medical records, a >30-mm lesion around the wisdom tooth shown via X-ray, colonectomy, radiotherapy treatment of the mandible, the lack of panoramic images, and lesions other than a follicular cyst. The DOI incidence was 1.1% (16 cases), and univariate analyses revealed that the development of DOI was significantly associated with the Winter classification (p = 0.003), position (p = 0.003), hypertension (p = 0.011), and hemostatic agent use (p = 0.004). A multivariate logistic regression analysis demonstrated that position (OR = B for A, 7.75; p = 0.0163), hypertension (OR = 7.60, p = 0.013), and hemostatic agent use (OR = 6.87, p = 0.0022) were significantly associated with DOI development. Hypertension, hemostatic use, and position were found to be key factors for DOI; long-term observation may thus be necessary for patients with these risk factors. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether stimulation of sacral spinal nerve roots can induce defecation in cats. In anesthetized cats, bipolar hook electrodes were placed on the S1-S3 dorsal and/or ventral roots. Stimulus pulses (1-50 Hz, 0.2 ms) were applied to an individual S1-S3 root to induce proximal/distal colon contractions and defecation. Balloon catheters were inserted into the proximal and distal colon to measure contraction pressure. Glass marbles were inserted into the rectum to demonstrate defecation by videotaping the elimination of marbles. Stimulation of the S2 ventral root at 7 Hz induced significantly (P < 0.05) larger contractions (32 ± 9 cmH2O) in both proximal and distal colon than stimulation of the S1 or S3 ventral root. Intermittent (5 times) stimulation (1 min on and 1 min off) of both dorsal and ventral S2 roots at 7 Hz produced reproducible colon contractions without fatigue, whereas continuous stimulation of 5-min duration caused significant fatigue in colon contractions. Stimulation (7 Hz) of both dorsal and ventral S2 roots together successfully induced defecation that eliminated 1 or 2 marbles from the rectum. This study indicates the possibility to develop a novel neuromodulation device to restore defecation function after spinal cord injury using a minimally invasive surgical approach to insert a lead electrode via the sacral foramen to stimulate a sacral spinal root.NEW & NOTEWORTHY This study in cats determined the optimal stimulation parameters and the spinal segment for sacral spinal root stimulation to induce colon contraction. The results have significant implications for design of a novel neuromodulation device to restore defecation function after spinal cord injury (SCI) and for optimizing sacral neuromodulation parameters to treat non-SCI people with chronic constipation. [ABSTRACT FROM AUTHOR]

Objective: This systematic review assesses the association of tooth loss (TL), as the exposure, with morbidity and mortality by diabetes mellitus (DM) status, as the outcome, in older adults. Background: Individuals with DM have higher prevalence of severe TL and increased risk of developing morbidities and mortality. No systematic review has evaluated the association between TL with morbidity and mortality by DM status. Material and methods: Comprehensive searches used multiple publication databases containing reports published between 01/01/2000 and 04/21/2021. Two authors independently evaluated included studies for quality and risk of bias using the Critical Appraisal Skills Programme (CASP) checklist for cohort and Center for Evidence-Based Medicine (CEBM) critical appraisal sheet for cross-sectional studies, while a third author arbitrated decisions to resolve disagreements. Results: Thirteen studies met the inclusion criteria: eight cross-sectional and five cohort. Qualitative review of the included studies indicated TL is associated with increased incidence and prevalence of DM. TL is also associated with DM-related morbidities including greater prevalence of heart disease, diabetic retinopathy, metabolic syndrome; poorer health-related quality of life; poorer survival of participants with chronic kidney disease; and increased medical expenditure. Overall, the quality of the evidence reviewed was medium, as per the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence. Conclusions/practical implications: This review found significant associations of TL with prevalence and incidence of DM and adverse DM-related outcomes. An interprofessional team-care approach that includes an oral health component could benefit the prevention and management of DM. [ABSTRACT FROM AUTHOR]

The ventral posterior medial nucleus (VPM) is amandatory relay for orofacial sensory information targeting the primary somatosensory cortex. We characterized the morphology of VPM axons arising in the principal trigeminal sensory nucleus (pV) through injections of biotinylated dextran amine (BDA) placed in pV of Macaca fascicularis and mulatta monkeys. Labeled terminals formed a patchy bilateral distribution. Within contralateral VPM, patches were found primarily, but not exclusively, within the laterally located, vertical segment, and in ipsilateral VPM, primarily, but not exclusively, in the medially located, horizontal segment. Two fiber types were labeled: thin and thick. Thin fibers were poorly branched and diffusely distributed. They were studded with small en passant boutons. Most labeled fibers were thick and they branched extensively to form distinctive terminal arbors decorated with numerous boutons that varied in size and shape. Quantitative analysis of thick fiber arbor features showed little difference between the sides, although contralateral boutons were significantly larger than ipsilateral ones. Bouton distribution with respect to counterstained somata suggests that proximal dendrites are their main target. Indeed, ultrastructural examination demonstrated that they provide large diameter dendrites with numerous contacts. Direct comparison of thick fiber terminal arbors to cytochrome oxidase (CO) staining revealed that these arbors are much smaller than individual CO-rich patches believed to designate rods containing discrete body area representations. Thus, each terminal arbor appears to heavily innervate a small number of VPM neurons within a rod. This relationship would serve to maintain relatively small receptive fields within the topographic representation of the face. [ABSTRACT FROM AUTHOR]

Taste and somatosensation both mediate protective behaviors. Bitter taste guides avoidance of ingestion of toxins while pain sensations, such as noxious heat, signal adverse conditions to ward off harm. Although brain pathways for taste and somatosensation are typically studied independently, prior data suggest that they intersect, potentially reflecting their common protective role. To investigate this, we applied electrophysiologic and optogenetic techniques in anesthetized mice of both sexes to evaluate relationships between oral somatosensory and taste activity in the parabrachial nucleus (PbN), implicated for roles in gustation and pain. Spikes were recorded from taste-active PbN neurons tested with oral delivery of thermal and chemesthetic stimuli, including agonists of nocisensitive transient receptor potential (TRP) ion channels on somatosensory fibers. Gustatory neurons were also tested to follow electrical pulse stimulation of an oral somatosensory region of the spinal trigeminal subnucleus caudalis (Vc), which projects to the PbN. Neurons composed classic taste groups, including sodium, electrolyte, appetitive, or bitter cells. Across groups, most neurons spiked to Vc pulse stimulation, implying that trigeminal projections reach PbN gustatory neurons. Among such cells, a subpopulation responsive to the bitter taste stimuli quinine and cydoheximide, and aversive concentrations of sodium, cofired to agonists of nocisensitive TRP channels, including capsaicin, mustard oil, and noxious heat. Such neurons populated the lateral PbN. Further, nociceptive activity in PbN bitter taste neurons was suppressed during optogenetic-assisted inhibition of the Vc, implying convergent trigeminal input contributed to such activity. Our results reveal a novel role for PbN gustatory cells in cross-system signaling related to protection. [ABSTRACT FROM AUTHOR]

Aims and Objectives: The aims of this study were to determine oral health-related quality of life (OHRQoL) among elderly people aged 65 and above years from Hafar Al-Batin area, Saudi Arabia, by utilizing Arabic version of Geriatric Oral Health Assessment Index (GOHAI-Ar). Materials and Methods: This was a cross-sectional study undertaken from October 2017 to December 2017. A convenience sampling methodology was employed to select the elderly patients aged ≥65 years attending dental clinics of primary health-care centers in five different regions of the Hafar Al-Batin, Saudi Arabia. OHRQoL of the participants was measured using the Saudi Arabian version of GOHAI-Ar. The oral examinations performed to record a total number of remaining natural teeth, complete and removable partial dentures, and fixed partial dentures. Descriptive and inferential statistics were performed. Results: A total of 200 elderly participants (M = 157 and F = 43) having mean age (± standard error [SE]) was 69.26 (±0.34) years, participated in the study. Mean ± SE of GOHAI-Ar was 27.68 ± 0.54, physical function 9.12 ± 0.26, pain and discomfort (6.87 ± 0.18), and psychological discomfort (11.69 ± 0.25). Remaining natural teeth and prosthodontic status significantly correlated with pain and discomfort. The presence of prosthesis was found to influence the psychological function. Gender and prosthodontic statuses were found to have significant correlation with OHRQoL. Conclusion: Poor OHRQoL among elderly from Hafar Al-Batin city was found, and presence dental prosthesis showed a positive impact on OHRQoL. [ABSTRACT FROM AUTHOR]

Eating and drinking generate sequential mechanosensory signals along the digestive tract. These signals are communicated to the brain for the timely initiation and regulation of diverse ingestive and digestive processes - ranging from appetite control and tactile perception to gut motility, digestive fluid secretion and defecation - that are vital for the proper intake, breakdown and absorption of nutrients and water. Gut mechanosensation has been investigated for over a century as a common pillar of energy, fluid and gastrointestinal homeostasis, and recent discoveries of specific mechanoreceptors, contributing ion channels and the well-defined circuits underlying gut mechanosensation signalling and function have further expanded our understanding of ingestive and digestive processes at the molecular and cellular levels. In this Review, we discuss our current understanding of the generation of mechanosensory signals from the digestive periphery, the neural afferent pathways that relay these signals to the brain and the neural circuit mechanisms that control ingestive and digestive processes, focusing on the four major digestive tract parts: the oral and pharyngeal cavities, oesophagus, stomach and intestines. We also discuss the clinical implications of gut mechanosensation in ingestive and digestive disorders., (© 2022. Springer Nature Limited.)

An ideal dental repair material should possess certain exclusive properties such as adequate adhesive ability, insolubility, dimensional stability, biocompatibility, bioactivity etc. New materials claiming better performance are continuously being introduced in the market to optimize the care of dental patients. Biodentine has been recently introduced as the "the first all-in-one, bioactive and biocompatible material for damaged dentin replacement". Manufacturers claim that Biodentine has noticeably shorter setting time in contrast to other silicate cements such as Mineral Trioxide Aggregate (MTA) and also has better mechanical and handling properties.This article is aimed to compare the properties of MTA and Biodentine analyzing the research work done in this field so far by various researchers all across the globe. [ABSTRACT FROM AUTHOR]

Background: Study results have shown that chronic exposure to cigarette smoke affects the taste function in humans. However, neither the quantitative impact on taste sensitivity nor the time-course of taste recovery on stopping smoking have been precisely examined. Methods: The experimental design included 2 phases, (i) a case--control phase comparing the taste sensitivity level measured by Electrogustometric (EGM) thresholds from various parts of the tongue (locus) between smokers (n =8 3 ) and non-smokers (n = 48), (ii) a follow-up study looking at the taste sensitivity recovery in smokers after smoking cessation (n = 24) and compared with non-smokers. Results: Smokers exhibited significantly lower taste sensitivity than non-smokers - the higher the nicotine dependence (Fagerström scores), the lower the taste sensitivity. After smoking cessation, EGM thresholds decreased progressively, and reached the taste sensitivity range of non-smokers depending on locus and time. After 2 weeks a recovery could be observed on the 3 Tip and the 2 edge loci; the recovery in the posterior loci was complete after 9 weeks, and in the dorsal loci recovery was observed only after 2 months or more. Conclusions: Smoking cessation does lead to a rapid recovery of taste sensitivity among smokers, with recovery time found to differ based on the sensitivity of loci of the tongue. The use of EGM could potentially be explored as a motivational tool for smoking cessation. [ABSTRACT FROM AUTHOR]

Every day our sensory systems perceive and integrate a variety of stimuli containing information vital for our survival. Pain acts as a protective warning system, eliciting a response to remove harmful stimuli; it may also be a symptom of an illness or present as a disease itself. There is a growing need for additional pain-relieving therapies involving the multisensory integration of smell and taste in pain modulation, an approach that may provide new strategies for the treatment and management of pain. While pain, smell, and taste share common features and are strongly linked to emotion and cognition, their interaction has been poorly explored. In this review, we provide an overview of the literature on pain modulation by olfactory and gustatory substances. It includes adult human studies investigating measures of pain threshold, tolerance, intensity, and/or unpleasantness. Due to the limited number of studies currently available, we have structured this review as a narrative in which we comment on experimentally induced and clinical pain separately on pain-smell and pain-taste interaction. Inconsistent study findings notwithstanding, pain, smell, and taste seem to interact at both the behavioral and the neural levels. Pain intensity and unpleasantness seem to be affected more by olfactory substances, whereas pain threshold and tolerance are influenced by gustatory substances. Few pilot studies to date have investigated these effects in clinical populations. While the current results are promising for the future, more evidence is needed to elucidate the link between the chemical senses and pain. Doing so has the potential to improve and develop novel options for pain treatment.

We coordinated anatomy and physiology lectures and practicals to facilitate an integrated understanding of morphology and function in a basic medical science program for dental students and to reduce the time spent on basic science education. This method is a means to provide the essential information and skills in less time. The overall impression was that the practice of joint central nervous system lectures and practicals was an efficient method for students, which suggests that joint lectures might also be useful for clinical subjects. About two-thirds of students felt that the joint anatomy and physiology lecture on the central nervous system was useful and necessary in understanding the relationship between morphology and function, at least for this subject. One-third of students were neutral on the effectiveness of this method. However, the survey results suggest that improvements are needed in the method and timing of joint lectures and practicals. The present teaching approach can be further improved by conducting combined lectures in which the form and function of anatomic structures are presented by the relevant departments during the same lecture. Finally, joint lecturers and practicals offer an opportunity to increase student understanding of the importance of new research findings by the present authors and other researchers. [ABSTRACT FROM AUTHOR]

Orofacial pain in patients relies on the anatomical pathways that conduct nociceptive information, originating from the periphery towards the trigeminal sensory nucleus complex (TSNC) and finally, to the thalami and the somatosensorical cortical regions. The anatomy and function of the so-called trigeminothalamic tracts have been investigated before. In these animal-based studies from the previous century, the intracerebral pathways were mapped using different retro- and anterograde tracing methods. We review the literature on the trigeminothalamic tracts focusing on these animal tracer studies. Subsequently, we related the observations of these studies to clinical findings using fMRI trials. The intracerebral trigeminal pathways can be subdivided into three pathways: a ventral (contralateral) and dorsal (mainly ipsilateral) trigeminothalamic tract and the intranuclear pathway. Based on the reviewed evidence we hypothesize the co-existence of an ipsilateral nociceptive conduction tract to the cerebral cortex and we translate evidence from animal-based research to the human anatomy. Our hypothesis differs from the classical idea that orofacial pain arises only from nociceptive information via the contralateral, ventral trigeminothalamic pathway. Better understanding of the histology, anatomy and connectivity of the trigeminal fibers could contribute to the discovery of a more effective pain treatment in patients suffering from various orofacial pain syndromes. [ABSTRACT FROM AUTHOR]

Copyright of Médecine Buccale Chirurgie Buccale is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Médecine Buccale Chirurgie Buccale is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The tongue rehabilitation technique developed by the physiotherapist Maryvonne Fournier may be prescribed in several medical disciplines: dentistry, orthodontics, oral and maxillofacial surgery, ENT, pulmonology, pediatrics, neurology and geriatrics. Other health care providers, such as speech therapists and dental hygienists, have also taken an interest in the technique. The aim of this article is to present a simplified non-operator-dependent version of the tongue dysfunction assessment protocol implemented in maxillofacial physiotherapy, that can be used by practitioners in all fields. [ABSTRACT FROM AUTHOR]

Copyright of Médecine Buccale Chirurgie Buccale is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The temperature of taste stimuli can modulate gustatory processing. Perceptual data indicate that the adapted temperature of oral epithelia also influences gustation, although little is known about the neural basis of this effect. Here, we electrophysiologically recorded orosensory responses (spikes) to 25°C (cool) and 35°C (warm) solutions of sucrose (0.1 and 0.3 M), NaCl (0.004, 0.1, and 0.3 M), and water from taste-sensitive neurons in the nucleus of the solitary tract in mice under varied thermal adaptation of oral epithelia. Conditions included presentation of taste stimuli isothermal to adaptation temperatures of 25°C (constant cooling) and 35°C (constant warming), delivery of 25°C stimuli following 35°C adaptation (relative cooling), and presentation of 35°C stimuli following 25°C adaptation (relative warming). Responses to sucrose in sucrose-oriented cells (n = 15) were enhanced under the constant and relative warming conditions compared with constant cooling, where contiguous cooling across adaptation and stimulus periods induced the lowest and longest latency responses to sucrose. Yet compared with constant warming, cooling sucrose following warm adaptation (relative cooling) only marginally reduced activity to 0.1 M sucrose and did not alter responses to 0.3 M sucrose. Thus, warmth adaptation counteracted the attenuation in sucrose activity associated with stimulus cooling. Analysis of sodium-oriented (n = 25) neurons revealed adaptation to cool water, and cooling taste solutions enhanced unit firing to 0.004 M (perithreshold) NaCl, whereas warmth adaptation and stimulus warming could facilitate activity to 0.3 M NaCl. The concentration dependence of this thermal effect may reflect a dual effect of temperature on the sodium reception mechanism that drives sodium-oriented cells. [ABSTRACT FROM AUTHOR]

Introduction: Over the past many years various root end filling materials have been used which have been tested for their physical properties but each of them had certain limitations. In clinical practice, root end filling materials are exposed to oral tissue fluids which may compromise their longevity. Aim: The aim of this study was to investigate the effects of oral tissue fluids on compressive strength of Mineral Trioxide Aggregate (MTA) and biodentine. Materials and Methods: MTA and biodentine cylinders measuring 6 mm × 4 mm were prepared using acrylic blocks. They were divided into six groups; (Group 1) (MTA) (n=3), (Group 2) MTA contaminated with saliva, (MTA-S) (n=3), Group 3: MTA contaminated with blood, MTA-B (n=3), Group 4: Biodentine (BD), Group 5: Biodentine contaminated with saliva (BD-S) (n=5), Group 6: Biodentine contaminated with blood (BD-B) (n=5). The mould was contaminated with saliva and blood and incubated at 37°C at 100% humidity for three days and compressive strength (MPa) was measured using universal testing machine and the data was analyzed statistically using one-way ANOVA test. Results: There was no significant difference in the compressive strength between the three groups i.e., MTA, MTA-S, MTA-B (p > 0.05). However, there was higher compressive strength in the MTA-B group when compared to MTA and MTA-S. Also,there was no statistical significant difference between BD, BD-S, BD-B (p>0.05). Conclusion: This study showed that the compressive strength of MTA and biodentine was not adversely affected by contamination with oral tissue fluids like blood and saliva. [ABSTRACT FROM AUTHOR]

Copyright of Médecine Buccale Chirurgie Buccale is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Changes in oral temperature can influence taste perception, indicating overlap among mechanisms for taste and oral somesthesis. Medullary gustatory neurons can show cosensitivity to temperature, albeit how these cells process combined taste and thermal input is poorly understood. Here, we electrophysiologically recorded orosensory responses (spikes) from 39 taste-sensitive neurons in the nucleus tractus solitarii of anesthetized mice during oral delivery of tastants adjusted to innocuous cool (16 and 18°C), room (22°C, baseline), and warm (30 and 37°C) oral temperatures. Stimuli included (in mM) 100 sucrose, 30 NaCl, 3 HCl, 3 quinine, an umami mixture, and water. Although cooled water excited few cells, water warmed to 30 and 37°C significantly excited 33% and 64% of neurons, respectively. Warmth induced responses of comparable magnitude to room temperature tastants. Furthermore, warming taste solutions influenced the distribution of gustatory responses among neurons and increased (P < 0.05) neuronal breadth of tuning across taste qualities. The influence of warmth on response magnitude was stimulus specific. Across neurons, warming facilitated responses to sucrose and umami in a superadditive manner, as these responses exceeded (P < 0.05) the arithmetic sum of activity to warming alone and the taste stimulus tested at room temperature. Superadditive increases (P < 0.05) in responding were also noted in some cells for warmed HCl. Yet warming induced only simple additive or subtractive effects on responses to quinine and NaCl. Data show temperature is a parameter of gustatory processing, like taste quality and concentration, in medullary circuits for taste. [ABSTRACT FROM AUTHOR]

Trigeminal primary afferent fibers have small receptive fields and discrete submodalities, but second order trigeminal neurons often display larger receptive fields with complex, multimodal responses. Moreover, while most large caliber afferents terminate exclusively in the principal trigeminal nucleus, and pars caudalis (sVc) of the spinal trigeminal nucleus receives almost exclusively small caliber afferents, the characteristics of second order neurons do not always reflect this dichotomy. These surprising characteristics may be due to a network of intratrigeminal connections modifying primary afferent contributions. This study characterizes the distribution and morphology of intratrigeminal cells and axons in a macaque monkeys. Tracer injections centered in the principal nucleus (pV) and adjacent pars oralis retrogradely labeled neurons bilaterally in pars interpolaris (sVi), but only ipsilaterally, in sVc. Labeled axons terminated contralaterally within sVi and caudalis. Features of the intratrigeminal cells in ipsilateral sVc suggest that both nociceptive and non-nociceptive neurons project to principalis. A commissural projection to contralateral principalis was also revealed. Injections into sVc labeled cells and terminals in pV and pars oralis on both sides, indicating the presence of bilateral reciprocal connections. Labeled terminals and cells were also present bilaterally in sVi and in contralateral sVc. Interpolaris injections produced labeling patterns similar to those of sVc. Thus, the rostral and caudal poles of the macaque trigeminal complex are richly interconnected by ipsilateral ascending and descending connections providing an anatomical substrate for complex analysis of oro-facial stimuli. Sparser reciprocal crossed intratrigeminal connections may be important for conjugate reflex movements, such as the corneal blink reflex. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate age-related changes in electrogustometry (EGM) thresholds, in morphology and density of the fungiform papillae (fPap) and in vessels’ shape and density at the tip of the human tongue.In 156 nonsmokers (74 males, 82 females; age range: 10–80 years), divided in age groups, EGM thresholds at the chorda tympani area, at the soft palate area, and at the area of the vallate papillae were recorded bilaterally. Morphology and density of the fPap and blood vessels’ density and morphology at the tip of the tongue were examined using contact endoscopy (CE). EGM thresholds at the chorda tympani area were significantly higher in both men and women ←60 years of age than in younger individuals. At the soft-palatine area, EGM thresholds were significantly higher in men aged 20–29 years and ←60 years compared with men of other age groups. In women older than 50 years, thresholds at all 3 areas were significantly higher than in the younger age groups. No significant differences in EGM thresholds between the two sexes at all locations tested were detected. The density of fPap decreased significantly in men aged >50 years and in women aged >60 years compared with younger individuals. Vascular density decreased significantly and vascular morphology worsened at the tip of the tongue in subjects older than 60 years of age compared with younger subjects. The study showed statistically significant differences in EGM thresholds between the right and the left side of the tongue and between the two sexes. Aging is associated with a progressive increase in EGM thresholds. Density of fPap plays an important role for taste acuity in females aged >60 years and males aged ←50 years. Morphology of fPap and vessels’ density and morphology at the tip of the tongue, as tested by CE, emerge as factors influencing taste function in subjects of both sexes aged >60 years. [ABSTRACT FROM AUTHOR]

The proposed biodynamic model of the articular disc joint has the ability to affect directly the complete chewing mechanism process and its related muscles defining its kinematics. When subjected to stresses from the mastication muscles, the disc absorbs one part and redistributes the other to become completely distorted. To develop a realistic model of this intricate joint a CT scan and MRI images from a patient were obtained to create sections (layers) and MRI images to create an anatomical joint CAD model, and its corresponding mesh element using a finite element method. The boundary conditions are described by the external forces applied to the joint model through a decomposition of the maximum muscular force developed by the same individual. In this study, the maximum force was operating at frequencies close to the actual chewing frequency measured through a cyclic loading condition. The reaction force at the glenoid fossa was found to be around 1035 N and is directly related to the frequency of indentation. It is also shown that over the years the areas of maximum stresses are located at the lateral portion of the disc and on its posterior rim. These forces can reach 13.2 MPa after a period of 32 seconds (s) at a frequency of 0.5 Hz. An important part of this study is to highlight resilience and the areas where stresses are at their maximum. This study provides a novel approach to improve the understanding of this complex joint, as well as to assess the different pathologies associated with the disc disease that would be difficult to study otherwise. [ABSTRACT FROM AUTHOR]

Study design:Histological examination of human spinal ventral roots.Objectives:To determine the proportion of unmyelinated fibers in human ventral roots from the 4th cervical (C4) to 2nd sacral (S2) segment, and to evaluate differences in the proportions of unmyelinated fibers between the cervical, thoracic, lumbar and sacral segments, and between autonomic and other segments.Setting:University Teaching Hospital, Busan, Korea.Methods:Eight embalmed adult human cadavers (six males and two females; mean age 56.3 years) were collected. The ventral root samples were obtained by transverse cuts of the ventral roots within 1 cm proximal to the medial portion of the dorsal root ganglion from the C4 to S2 segment. The number of unmyelinated and myelinated fibers was counted in four fields, and the mean number of unmyelinated fibers was calculated. The percentage of unmyelinated fibers was calculated from the ratio of unmyelinated fibers to total fibers (myelinated fibers+unmyelinated fibers).Results:The mean percentages of unmyelinated axons in cervical (C4–C8), thoracic (T1–T12), lumbar (L1–L5) and sacral (S1–S2) ventral roots were 16.3, 21.4, 17.8 and 20.7%, respectively. The percentage of unmyelinated fibers in thoracic ventral roots was higher than that for other segments (P<0.001). There was no significant difference in proportions of unmyelinated fibers between the sympathetic segments (T11–L2), parasympathetic segments (S2) and the other segments (C4–T10 and L3–S1) (P=0.1784).Conclusions:Approximately 20% of human spinal ventral root fibers were unmyelinated. The proportion of unmyelinated fibers was highest in the thoracic segments.Spinal Cord (2009) 47, 286–289; doi:10.1038/sc.2008.97; published online 5 August 2008 [ABSTRACT FROM AUTHOR]

Glutamate is the most abundant excitatory amino acid in the central nervous system. Neurons using glutamate as a neurotransmitter can be characterised by vesicular glutamate transporters (VGLUTs). Among the three subtypes, VGLUT3 is unique, co-localising with other "classical" neurotransmitters, such as the inhibitory GABA. Glutamate, manipulated by VGLUT3, can modulate the packaging as well as the release of other neurotransmitters and serve as a retrograde signal through its release from the somata and dendrites. Its contribution to sensory processes (including seeing, hearing, and mechanosensation) is well characterised. However, its involvement in learning and memory can only be assumed based on its prominent hippocampal presence. Although VGLUT3-expressing neurons are detectable in the hippocampus, most of the hippocampal VGLUT3 positivity can be found on nerve terminals, presumably coming from the median raphe. This hippocampal glutamatergic network plays a pivotal role in several important processes (e.g., learning and memory, emotions, epilepsy, cardiovascular regulation). Indirect information from anatomical studies and KO mice strains suggests the contribution of local VGLUT3-positive hippocampal neurons as well as afferentations in these events. However, further studies making use of more specific tools (e.g., Cre-mice, opto- and chemogenetics) are needed to confirm these assumptions. [ABSTRACT FROM AUTHOR]

Whenever food is placed in the mouth, taste receptors are stimulated. Simultaneously, different types of sensory fibre that monitor several food attributes such as texture, temperature and odour are activated. Here, we evaluate taste and oral somatosensory peripheral transduction mechanisms as well as the multi-sensory integrative functions of the central pathways that support the complex sensations that we usually associate with gustation. On the basis of recent experimental data, we argue that these brain circuits make use of distributed ensemble codes that represent the sensory and post-ingestive properties of tastants. [ABSTRACT FROM AUTHOR]

This study investigated effects of nicotine applied to the tongue surface on responses of gustatory neurons in the nucleus of the solitary tract (NTS) in rats. In pentobarbital-anesthetized rats, single-unit recordings were made from NTS units responsive to one or more tastants (sucrose, NaCl, citric acid, monosodium glutamate, quinine). Application of nicotine (0.87, 8.7, or 600 mM) excited gustatory NTS units and significantly attenuated NTS unit responses to their preferred tastant in a dose-dependent manner. The depressant effect of nicotine was equivalent regardless of which tastant best excited the NTS unit. Nicotinic excitation of NTS units and depression of their tastant-evoked responses were both significantly attenuated by the nicotinic antagonist mecamylamine, which itself did not excite NTS units. In rats with bilateral trigeminal ganglionectomy, nicotine still excited nearly all NTS units but no longer depressed tastant-evoked responses. Nicotine did not elicit plasma extravasation when applied to the tongue. The results indicate that nicotine directly excites NTS units by gustatory nerves and inhibits their tastant-evoked responses by a nicotinic acetylcholine receptor-mediated excitation of trigeminal afferents that inhibit NTS units centrally. [ABSTRACT FROM AUTHOR]

When scientists describe their research to non-scientists, the most common question is 'what is the practical value of your work?' The methods that are used to measure responses to sensory stimuli in human sensory science and neuroscience research have great potential value to the food and wine industries, as well as promising to advance our understanding of the mechanisms by which sensations are perceived and processed. [ABSTRACT FROM AUTHOR]

Dentists account for up to 10% of all prescribed antibiotics in primary care, with up to 80% being inappropriate. Targeted approaches to change prescription behavior are scarce. This study aimed at identifying specific barriers and facilitators for prudent antibiotic use in German dentistry by using qualitative methods. Nine in-depth interviews and two focus group discussions with another nine dentists were conducted and analyzed thematically. Dentists described being conflicted by the discordance of available treatment time and the necessity of thorough therapy. Lacking the opportunity of follow-up led to uncertainty. Dentists felt a lack of medical competency concerning prophylaxis for infectious endocarditis. A lack of empowerment to make therapeutic decisions interfered with guideline-conformity. The communication with fellow physicians is conflictual and improvement was wished for. In consequence, dentists felt pressure by potential medico-legal liability. Patients demanding quick and easy pain relief put extra strain on the interviewed dentists. Our hypotheses concord with preliminary data, mainly from the UK, but highlighted specifically medico-legal concerns and interprofessional communication as even greater barriers as described before. Tailored interventional concepts based on our findings may have the potential to lower antibiotic prescriptions in German primary dental care. [ABSTRACT FROM AUTHOR]

Background and objectives: Infections caused by resistant bacteria are a growing public health problem that is linked to many different causes, among them the antibiotics' incorrect use plays an important role. According to the World Health Organization (WHO) the most dangerous behaviors are the early interruption of antibiotic therapy and the use of molecules without appropriate prescription. The authors conducted a systematic review to assess if antibiotic prescription with different regimens is connected to the onset of bacterial resistance. Methods: The authors performed an electronic and manual literature search on four databases (Web of Science, Scopus, PubMed, and Cochrane Register of Controlled Trials) from their inception to 15 June 2019. The date of the last search was 27 November 2019. Any article comparing cultural or genic analysis of resistance in patients that took antibiotics with at least two different regimens was included. No language restrictions were applied. Risk of bias for randomized controlled trials (RCTs) was assessed using the Cochrane collaboration's tool whereas case-control and cohort studies were evaluated through the Newcastle–Ottawa scale. Results: The initial search resulted in a total of 1744 titles. After careful evaluation of all results, only three studies satisfied the outcome of the present review. From the qualitative analysis of data, it emerges that even if antibiotics are administered for a shorter period than the conventional one the species that inhabit the oral cavity can adapt quickly and express genes of antibiotic resistance. Additional evidence from this analysis is that not only does the proportion of resistant bacteria increase in the oral cavity, but also in more distant districts such as the intestine. Conclusions: Despite the great number of studies retrieved by electronic databases only few studies investigated the target of this review. The reason for this evidence is that it is not ethical to investigate and compare different antibiotic regimens, shorter or longer than the appropriate one. This evidence is applicable both to prophylactic administrations and to those aimed at treating infections. Besides this, the WHO affirms that, in the absence of infective complications, the prescription of antibiotic after every type of surgical intervention cannot be admitted and that studies dealing with antibiotic regimens that do not comply with drug's pharmacodynamics characteristics cannot be ethically admitted. PROSPERO acknowledgement of receipt [149149]. [ABSTRACT FROM AUTHOR]

The term “pain threshold” refers to the measurement of the intensity of a physical stimulus that evokes pain. To estimate the pain threshold, a mechanical or electrical stimulus with increasing intensity is usually applied until the subject under evaluation refers to a pain sensation. This study aims to evaluate the autoalgometric pain threshold as a perfect technique to determine the effects of stimulation rate in relation to both gender and the site of stimulation. In this experimental model, pressure algometry was applied: the subject under evaluation pushed a finger against a small round metal tip, producing and at the same time controlling the intensity of the noxious stimulus. Through autoalgometry, the stimulus intensity was recorded over time, measuring the force change rate applied and studying the subject’s behavior on approaching pain. This test was performed with 50 healthy volunteers on two days, applying a fast or slow rate of stimulation. The results described demonstrate that there is a positive correlation between the pressure increase rate and the pressure threshold evaluation. In light of these findings, autoalgometry can be proposed as an objective measure of pressure pain threshold for clinical and research use. [ABSTRACT FROM AUTHOR]