Students' perceptions of virtual interactive clinical case-based learning: A comparative study with three different cohorts.

Background/purpose: Since the introduction of virtual learning into dental education, students' perceptions of the effectiveness of virtual versus in-person learning formats have evolved for interactive clinical case-based learning (ICCBL). This study aimed to undertake a comparative analysis of three different cohorts that received various formats of ICCBL instruction. Materials and methods: A survey was distributed to the Classes of 2023, 2024, and 2025 following each class completion of interactive clinical case-based-tutorials (ICCBT) as part of the Treatment of Active Disease (TxAD) course at Harvard School of Dental Medicine. Results: A total of eighty-five participants from the three cohorts, twenty-three students from the Class of 2023 (virtual format, 71.9 % participation rate), thirty-one students from the Class of 2024 (combination of virtual and in-person, 91.2 %), and thirty-one students from the Class of 2025 (in-person, 83.8 %) completed the post-course survey. Across three classes, all cohorts were more likely to perceive the virtual format as more effective than in-person ICCBT. In addition, the classes were more likely to prefer virtual based classes compared to in-person tutorials in the future. Conclusion: This study highlights the dynamic shifts in educational approaches to align with the evolving demands of contemporary students. Our findings show that all cohorts expressed a preference for virtual ICCBT sessions and perceived virtual ICCBT sessions as somewhat more effective for learning compared to in-person sessions. These findings challenge the notion that such sessions must be conducted in person, prompting further research and the exploration of potentially more effective and optimized educational methods.

Evaluating dental student self-assessment across preclinical anatomy waxing and operative exercises.

PURPOSE/OBJECTIVE: A career in healthcare is built on the foundations of continuous self-reflection and self-assessment. Previous studies have solely compared student self-assessment to faculty grades in a single discipline. The objective of this study was to investigate whether associations of a student's self-assessment skills exist across multiple disciplines in the predoctoral setting. METHODS: Sixty-five students from two class years at the Harvard School of Dental Medicine completed preclinical competency exams in dental anatomy waxing and operative dentistry. The difference between the student's self-assessment score and average faculty grade for each exercise was calculated as the student‒faculty (S-F) gap, which served as a proxy to determine how students evaluate their work. Regression analysis was performed to assess associations between wax-up and preclinical operative S-F gaps. RESULTS: Mean S-F gaps for waxing and preclinical operative procedures were positive (5.7 ± 6.1 and 7.6 ± 6.7, respectively). Additionally, students in the lower quartile tended to overestimate performance to a greater degree than their peers in the upper quartile. Furthermore, the waxing S-F gaps were positively associated with S-F gaps of each operative procedure, particularly with the combined operative exercise S-F gaps, where a statistically significant association was seen (coefficient = 0.28; p = 0.04). CONCLUSION(S): Previously, we identified a negative correlation between students' self-assessment skills (S-F gaps) and their preclinical performance. In this study, we further demonstrated an association of S-F gaps in two fundamental exercises: wax-up and operative dentistry. This underscores the roles of S-F gaps as possible indicators of students' preclinical and clinical performance, and it holds potential to become a widely standardized and applicable calculation that may help evaluate the effectiveness of the dental curricula and optimize student learning.

Association of student performance between dental anatomy waxing and preclinical operative dentistry.

Spatial perception and psychomotor skills are critical components to clinical dentistry. However, measures within the dental school curricula have not been sufficiently studied and evaluated for their effectiveness in predicting preclinical performance. The objective of this study was to examine whether students' waxing skills are associated with preclinical operative performance. This study included 65 students from two class years at the Harvard School of Dental Medicine. Regression analysis was utilized to assess associations between waxing scores and operative exam scores. Waxing scores were found to be positively correlated with all operative practical exam scores and significantly associated with the class III resin composite restoration (coefficient, 0.42; P = 0.02) and the combined operative exam scores (coefficient, 0.33; P = 0.04). Wax-up assessments could serve as a predictor for preclinical performance and identify students who would benefit from additional assistance to help foster a more inclusive learning environment.

Neuronal-immune axis alters pain and sensory afferent damage during dental pulp injury.

ABSTRACT: Dental pulp tissue is densely innervated by afferent fibers of the trigeminal ganglion. When bacteria cause dental decay near the pulpal tissue, a strong neuronal and immune response occurs, creating pulpitis, which is associated with severe pain and pulp tissue damage. Neuroimmune interactions have the potential to modulate both the pain and pathological outcome of pulpitis. We first investigated the role of the neuropeptide calcitonin gene-related peptide (CGRP), released from peptidergic sensory afferents, in dental pain and immune responses by using Calca knockout (Calca -/- ) and wild-type (Calca +/+ ) mice, in a model of pulpitis by creating a mechanical exposure of the dental pulp horn. We found that the neuropeptide CGRP, facilitated the recruitment of myeloid cells into the pulp while also increasing spontaneous pain-like behavior 20% to 25% at an early time point. Moreover, when we depleted neutrophils and monocytes, we found that there was 20% to 30% more sensory afferent loss and increased presence of bacteria in deeper parts of the tissue, whereas there was a significant reduction in mechanical pain response scores compared with the control group at a later time point. Overall, we showed that there is a crosstalk between peptidergic neurons and neutrophils in the pulp, modulating the pain and inflammatory outcomes of the disease.

Association between gender and self-assessment skills amongst Japanese dental students.

Background/purpose: Self-assessment in dental education is considered a fundamental skill for proficient oral healthcare providers. While previous studies looked at self-assessment in education, few have done so at Japanese institutions. This study aimed to assess potential associations between gender and self-assessment skills in Japanese dental students. Materials and methods: Dental students from Niigata University (n = 301) completed preclinical prosthodontic exercises and self-assessed their practical exam performance. Three calibrated faculty evaluated students' work using the same rubric. The difference between student self-assessment score and mean faculty grade was defined as the student-faculty (S-F) gap, indicating how accurately students evaluated their work. The gap scores were stratified by quartiles by faculty grade and by gender. Regression analysis was used to investigate potential associations. Results: Students mean S-F gap was 2.9 ± 10.5 % with a significant negative association to faculty grades (coefficient, -0.32; P < 0.001). There was no significant difference between male and female students for faculty grades, self-assessment scores, and S-F gaps. When stratified by quartile, mean S-F gaps of bottom quartile students (5.7 ± 11.9 %) were significantly higher than the rest of the class (1.9 ± 9.8 %; P = 0.01), while the mean S-F gaps of students in the top quartile (-0.8 ± 10.2 %) were significantly lower than the rest of the class (4.2 ± 10.3 %; P < 0.001). Conclusion: Niigata University students generally overestimated their performance. Students with higher faculty grades self-assessed themselves more accurately than students with lower faculty grades. Gender did not influence S-F gaps, despite dentistry in Japan shifting toward a female-dominated field.

SHIELD: Skull-shaped hemispheric implants enabling large-scale electrophysiology datasets in the mouse brain.

To understand the neural basis of behavior, it is essential to measure spiking dynamics across many interacting brain regions. Although new technologies, such as Neuropixels probes, facilitate multi-regional recordings, significant surgical and procedural hurdles remain for these experiments to achieve their full potential. Here, we describe skull-shaped hemispheric implants enabling large-scale electrophysiology datasets (SHIELD). These 3D-printed skull-replacement implants feature customizable insertion holes, allowing dozens of cortical and subcortical structures to be recorded in a single mouse using repeated multi-probe insertions over many days. We demonstrate the procedure's high success rate, biocompatibility, lack of adverse effects on behavior, and compatibility with imaging and optogenetics. To showcase SHIELD's scientific utility, we use multi-probe recordings to reveal novel insights into how alpha rhythms organize spiking activity across visual and sensorimotor networks. Overall, this method enables powerful, large-scale electrophysiological experiments for the study of distributed neural computation.

Defining the Performance of Clinician's Ability to Screen for Laryngeal Mass From Voice.

OBJECTIVE: Defining a clinician's ability to perceptually identify mass from voice will inform the feasibility, design priorities, and performance standards for tools developed to screen for laryngeal mass from voice. This study defined clinician ability of and examined the impact of expertise on screening for laryngeal mass from voice. STUDY DESIGN: Task comparison study between experts and nonexperts rating voices for the probability of a laryngeal mass. SETTING: Online, remote. METHODS: Experts (voice-focused speech-language pathologists and otolaryngologists) and nonexperts (general medicine providers) rated 5-s/i/voice samples (with pathology defined by laryngoscopy) for the probability of laryngeal mass via an online survey. The intraclass correlation coefficient (ICC) estimated interrater and intrarater reliability. Diagnostic performance metrics were calculated. A linear mixed effects model examined the impact of expertise and pathology on ratings. RESULTS: Forty clinicians (21 experts and 19 nonexperts) evaluated 344 voice samples. Experts outperformed nonexperts, with a higher area under the curve (70% vs 61%), sensitivity (49% vs 36%), and specificity (83% vs 77%) (all comparisons p < .05). Interrater reliability was fair for experts and poor for nonexperts (ICC: 0.48 vs 0.34), while intrarater reliability was excellent and good, respectively (ICC: 0.9 and 0.6). The main effects of expertise and underlying pathology were significant in the linear model (p < .001). CONCLUSION: Clinicians demonstrate inadequate performance screening for laryngeal mass from voice to use auditory perception for dysphonia triage. Experts' superior performance indicates that there is acoustic information in a voice that may be utilized to detect laryngeal mass based on voice.

Iron status influences mitochondrial disease progression in Complex I-deficient mice.

Mitochondrial dysfunction caused by aberrant Complex I assembly and reduced activity of the electron transport chain is pathogenic in many genetic and age-related diseases. Mice missing the Complex I subunit NADH dehydrogenase [ubiquinone] iron-sulfur protein 4 (NDUFS4) are a leading mammalian model of severe mitochondrial disease that exhibit many characteristic symptoms of Leigh Syndrome including oxidative stress, neuroinflammation, brain lesions, and premature death. NDUFS4 knockout mice have decreased expression of nearly every Complex I subunit. As Complex I normally contains at least 8 iron-sulfur clusters and more than 25 iron atoms, we asked whether a deficiency of Complex I may lead to iron perturbations, thereby accelerating disease progression. Consistent with this, iron supplementation accelerates symptoms of brain degeneration in these mice, while iron restriction delays the onset of these symptoms, reduces neuroinflammation, and increases survival. NDUFS4 knockout mice display signs of iron overload in the liver including increased expression of hepcidin and show changes in iron-responsive element-regulated proteins consistent with increased cellular iron that were prevented by iron restriction. These results suggest that perturbed iron homeostasis may contribute to pathology in Leigh Syndrome and possibly other mitochondrial disorders.

Iron is a mineral that contributes to many vital body functions. But as people age, it accumulates in many organs, including the liver and the brain. Excess iron accumulation is linked to age-related diseases like Parkinson's disease. Too much iron may contribute to harmful chemical reactions in the body. Usually, the body has systems in place to mitigate this harm, but these mechanisms may fail as people age. Uncontrolled iron accumulation may damage essential proteins, DNA and fats in the brain. These changes may kill brain cells causing neurodegenerative diseases like Parkinson's disease. Mitochondria, the cell's energy-producing factories, use and collect iron inside cells. As people age, mitochondria fail, which is also linked with age-related diseases. It has been unclear if mitochondrial failure may also contribute to iron accumulation and associated diseases like Parkinson's. Kelly et al. show that mitochondrial dysfunction causes iron accumulation and contributes to neurodegeneration in mice. In the experiments, Kelly et al. used mice with a mutation in a key-iron processing protein in mitochondria. These mice develop neurodegenerative symptoms and die early in life. Feeding the mice a high-iron diet accelerated the animals' symptoms. But providing them with an iron-restricted diet slowed their symptoms and extended their lives. Low-iron diets also slowed iron accumulation in the animal's liver and reduced brain inflammation. The experiments suggest that mitochondrial dysfunction contributes to both iron overload and brain degeneration. The next step for scientists is understanding the processes leading to mitochondrial dysfunction and iron accumulation. Then, scientists can determine if they can develop treatments targeting these processes. This research might lead to new treatments for Parkinson's disease or other age-related conditions caused by iron overload.

Recurrent pattern completion drives the neocortical representation of sensory inference.

When sensory information is incomplete or ambiguous, the brain relies on prior expectations to infer perceptual objects. Despite the centrality of this process to perception, the neural mechanism of sensory inference is not known. Illusory contours (ICs) are key tools to study sensory inference because they contain edges or objects that are implied only by their spatial context. Using cellular resolution, mesoscale two-photon calcium imaging and multi-Neuropixels recordings in the mouse visual cortex, we identified a sparse subset of neurons in the primary visual cortex (V1) and higher visual areas that respond emergently to ICs. We found that these highly selective 'IC-encoders' mediate the neural representation of IC inference. Strikingly, selective activation of these neurons using two-photon holographic optogenetics was sufficient to recreate IC representation in the rest of the V1 network, in the absence of any visual stimulus. This outlines a model in which primary sensory cortex facilitates sensory inference by selectively strengthening input patterns that match prior expectations through local, recurrent circuitry. Our data thus suggest a clear computational purpose for recurrence in the generation of holistic percepts under sensory ambiguity. More generally, selective reinforcement of top-down predictions by pattern-completing recurrent circuits in lower sensory cortices may constitute a key step in sensory inference.

Non-aureus Staphylococci and Bovine Udder Health: Current Understanding and Knowledge Gaps.

Despite considerable efforts to control bovine mastitis and explain its causes, it remains the most costly and common disease of dairy cattle worldwide. The role and impact of non-aureus staphylococci (NAS) in udder health are not entirely understood. These Gram-positive bacteria have become the most frequently isolated group of bacteria in milk samples of dairy cows and are associated with (mild) clinical and subclinical mastitis. Different species and strains of NAS differ in their epidemiology, pathogenicity, virulence, ecology and host adaptation, and antimicrobial resistance profiles. They have distinct relationships with the microbiome composition of the udder and may also have protective effects against other mastitis pathogens. Some appear to persist on the skin and in the teat canal and udder, while others seem to be transient residents of the udder from the environment. Analyzing genotypic and phenotypic differences in individual species may also hold clues to why some appear more successful than others in colonizing the udder. Understanding species-level interactions within the microbiome and its interactions with host genetics will clarify the role of NAS in bovine mastitis and udder health.