Visuo-Haptic VR and AR Guidance for Dental Nerve Block Education.

The inferior alveolar nerve block (IANB) is a dental anesthetic injection that is critical to the performance of many dental procedures. Dental students typically learn to administer an IANB through videos and practice on silicone molds and, in many dental schools, on other students. This causes significant stress for both the students and their early patients. To reduce discomfort and improve clinical outcomes, we created an anatomically informed virtual reality headset-based educational system for the IANB. It combines a layered 3D anatomical model, dynamic visual guidance for syringe position and orientation, and active force feedback to emulate syringe interaction with tissue. A companion mobile augmented reality application allows students to step through a visualization of the procedure on a phone or tablet. We conducted a user study to determine the advantages of preclinical training with our IANB simulator. We found that in comparison to dental students who were exposed only to traditional supplementary study materials, dental students who used our IANB simulator were more confident administering their first clinical injections, had less need for syringe readjustments, and had greater success in numbing patients.

Origami-Based Haptic Syringe for Local Anesthesia Simulator.

Although medical simulators have benefited from the use of haptics and virtual reality (VR) for decades, the former has become the bottleneck in producing a low-cost, compact, and accurate training experience. This is particularly the case for the inferior alveolar nerve block (IANB) procedure in dentistry, which is one of the most difficult motor skills to acquire. As existing works are still oversimplified or overcomplicated for practical deployment, we introduce an origami-based haptic syringe interface for IANB local anesthesia training. By harnessing the versatile mechanical tunability of the Kresling origami pattern, our interface simulated the tactile experience of the plunger while injecting the anesthetic solution. We present the design, development, and characterization process, as well as a preliminary usability study. The force profile generated by the syringe interface is perceptually similar with that of the Carpule syringe. The usability study suggests that the haptic syringe significantly improves the IANB training simulation and its potential to be utilized in several other medical training/simulation applications.

Effect of the haptic anchors during balancing and walking tasks in older adults: A systematic review.

BACKGROUND: Older adults are benefited from the continuous tactile information to enhance postural control. Therefore, the aim was to evaluate the effect of the haptic anchors during balancing and walking tasks in older adults. METHODS: The search strategy (up to January 2023) was based on the PICOT (older adults; anchor system during balance and walking tasks; any control group; postural control measurements; short and/or long-term effect). Two pairs of reviewers independently examined all titles and abstracts for eligibility. The reviewers independently extracted data from the included studies, assessed the risk of bias, and certainty of the evidence. RESULTS: Six studies were included in the qualitative synthesis. All studies used a 125-g haptic anchor system. Four studies used anchors when standing in a semi-tandem position, two in tandem walking on different surfaces, and one in an upright position after plantar flexor muscle fatigue. Two studies showed that the anchor system reduced body sway. One study showed that the ellipse area was significantly lower for the 50% group (reduced frequency) in the post-practice phase. One study showed that the reduction in the ellipse area was independent of the fatigue condition. Two studies observed reduced trunk acceleration in the frontal plane during tandem waking tasks. The studies had low to moderate certainty of evidence. CONCLUSION: Haptic anchors can reduce postural sway during balance and walking tasks in older adults. Also, positive effects were seen during the delayed post-practice phase after the removal of anchors only in individuals who used a reduced anchor frequency.

Transforming musculoskeletal anatomy learning with haptic surface painting.

Anatomical body painting has traditionally been utilized to support learner engagement and understanding of surface anatomy. Learners apply two-dimensional representations of surface markings directly on to the skin, based on the identification of key landmarks. Esthetically satisfying representations of musculature and viscera can also be created. However, established body painting approaches do not typically address three-dimensional spatial anatomical concepts. Haptic Surface Painting (HSP) is a novel activity, distinct from traditional body painting, and aims to develop learner spatial awareness. The HSP process is underpinned by previous work describing how a Haptico-visual observation and drawing method can support spatial, holistic, and collaborative anatomy learning. In HSP, superficial and underlying musculoskeletal and vascular structures are located haptically by palpation. Transparent colors are then immediately applied to the skin using purposive and cross-contour drawing techniques to produce corresponding visual representations of learner observation and cognition. Undergraduate students at a United Kingdom medical school (n = 7) participated in remote HSP workshops and focus groups. A phenomenological study of learner perspectives identified four themes from semantic qualitative analysis of transcripts: Three-dimensional haptico-visual exploration relating to learner spatial awareness of their own anatomy; cognitive freedom and accessibility provided by a flexible and empowering learning process; altered perspectives of anatomical detail, relationships, and clinical relevance; and delivery and context, relating to curricular integration, session format, and educator guidance. This work expands the pedagogic repertoire of anatomical body painting and has implications for anatomy educators seeking to integrate innovative, engaging, and effective learning approaches for transforming student learning.

A pilot study of local anesthesia training using a mixed-reality haptic fidelity model.

PURPOSE/OBJECTIVES: One of the most difficult local anesthetic blocks to master in dentistry is the inferior alveolar nerve block (IANB). Historically, dental students have practiced local anesthesia on one another. At the University of Colorado, these practice sessions have been limited to one required laboratory session. The predictability and confidence of student IANB success have not been high in the past. Therefore, the objective of this study was to investigate the impact of a novel IANB simulator, built on a three dimensional (3D)-printed mixed-reality haptic model, for second-year dental students to practice on prior to their laboratory session. METHODS: Thirty-nine student participants volunteered to practice with the IANB simulator. Participants were divided into two groups, Group A and Group B. Self-reported confidence and injection-specific accuracy were measured during IANB simulator practice and the laboratory session. During lab, partner numbness was assessed as a measure of IANB success. Groups A (n = 20) and B (n = 19) practiced with the simulator before and after laboratory, respectively. Injection domains were not assessed during Group B's practice with the IANB simulator. RESULTS: Self-reported confidence increased for both groups (p < 0.001). However, for anesthetic success, Group A exhibited significantly greater success (52.6%) than Group B (17.6%) (p = 0.029). CONCLUSION: Self-reported confidence in performing an IANB improved and higher anesthetic success was achieved for Group A. Further investigation is necessary to determine the long-term impact of using the IANB simulator in dental education.

User-Centered Design Methodologies for the Prototype Development of a Smart Harness and Related System to Provide Haptic Cues to Persons with Parkinson's Disease.

This paper describes the second part of the PASSO (Parkinson smart sensory cues for older users) project, which designs and tests an innovative haptic biofeedback system based on a wireless body sensor network using a smartphone and different smartwatches specifically designed to rehabilitate postural disturbances in persons with Parkinson's disease. According to the scientific literature on the use of smart devices to transmit sensory cues, vibrotactile feedback (particularly on the trunk) seems promising for improving people's gait and posture performance; they have been used in different environments and are well accepted by users. In the PASSO project, we designed and developed a wearable device and a related system to transmit vibrations to a person's body to improve posture and combat impairments like Pisa syndrome and camptocormia. Specifically, this paper describes the methodologies and strategies used to design, develop, and test wearable prototypes and the mHealth system. The results allowed a multidisciplinary comparison among the solutions, which led to prototypes with a high degree of usability, wearability, accessibility, and effectiveness. This mHealth system is now being used in pilot trials with subjects with Parkinson's disease to verify its feasibility among patients.

Novel Soft Haptic Biofeedback-Pilot Study on Postural Balance and Proprioception.

Sensory feedback is critical in proprioception and balance to orchestrate muscles to perform targeted motion(s). Biofeedback plays a significant role in substituting such sensory data when sensory functions of an individual are reduced or lost such as neurological disorders including stroke causing loss of sensory and motor functions requires compensation of both motor and sensory functions. Biofeedback substitution can be in the form of several means: mechanical, electrical, chemical and/or combination. This study proposes a soft monolithic haptic biofeedback device prototyped and pilot tests were conducted with healthy participants that balance and proprioception of the wearer were improved with applied mechanical stimuli on the lower limb(s). The soft monolithic haptic biofeedback device has been developed and manufactured using fused deposition modelling (FDM) that employs soft and flexible materials with low elastic moduli. Experimental results of the pilot tests show that the soft haptic device can effectively improve the balance of the wearer as much as can provide substitute proprioceptive feedback which are critical elements in robotic rehabilitation.

Adults' spatial scaling from memory: Comparing the visual and haptic domain.

The current study compared adults' spatial scaling from memory in the visual and haptic domain. Adults (N = 32, ages 19-27 years) were presented with a spatial-scaling task in a visual condition as well as a haptic condition (in which participants were blindfolded throughout the experimental session). In both conditions, they were presented with an embossed graphic including a target (i.e., a map). Then, they were asked to encode this map and to place a disc at the same spot on an empty referent space from memory. Maps had three different sizes whereas the referent space had a constant size, resulting in three different scaling factors (1:1, 1:2, 1:4). Participants' response times and absolute errors were measured. Order of perceptual condition was counterbalanced across participants. Analyses indicated that response times and absolute errors increased linearly with higher scaling factors in the visual as well as the haptic perceptual condition. In analogy to mental imagery research, these results suggest the usage of mental transformation strategies for spatial scaling.