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Autonomous vehicles are expected to take complete control of the driving process, enabling the former drivers to act as passengers only. This could lead to increased sickness as they can be engaged in tasks other than driving. Adopting different sickness mitigation techniques gives us unique types of motion sickness in autonomous vehicles to be studied. In this paper, we report on a study where we explored the possibilities of assessing motion sickness with electrogastrography (EGG), a non-invasive method used to measure the myoelectric activity of the stomach, and its potential usage in autonomous vehicles (AVs). The study was conducted in a high-fidelity driving simulator with a virtual reality (VR) headset. There separate EGG measurements were performed: before, during and after the driving AV simulation video in VR. During the driving, the participants encountered two driving environments: a straight and less dynamic highway road and a highly dynamic and curvy countryside road. The EGG signal was recorded with a proprietary 3-channel recording device and Ag/AgCl cutaneous electrodes. In addition, participants were asked to signalize whenever they felt uncomfortable and nauseated by pressing a special button. After the drive they completed also the Simulator Sickness Questionnaire (SSQ) and reported on their overall subjective perception of sickness symptoms. The EGG results showed a significant increase of the dominant frequency (DF) and the percentage of the high power spectrum density (FSD) as well as a significant decrease of the power spectrum density Crest factor (CF) during the AV simulation. The vast majority of participants reported nausea during more dynamic conditions, accompanied by an increase in the amplitude and the RMS value of EGG. Reported nausea occurred simultaneously with the increase in EGG amplitude. Based on the results, we conclude that EGG could be used for assessment of motion sickness in autonomous vehicles. DF, CF and FSD can be used as overall sickness indicators, while the relative increase in amplitude of EGG signal and duration of that increase can be used as short-term sickness indicators where the driving environment may affect the driver.

Surface electrogastrography (EGG) is a non-invasive technique that is used to record myoelectrical activity of the stomach using cutaneous electrodes placed on the abdomen. Gastric motility assessment by EGG is a candidate for standard clinical procedure based on the quantification of parameters characteristic of gastric motility disorders. Despite its noticeable benefits, EGG is not widely implemented in clinical practice. The main reasons are: (1) lack of standardization of electrode placement, (2) time-consuming diagnostic procedures and (3) a complex multi-channel recording setup. We proposed a methodology in which an easy-to-use single-channel EGG, with a less time-consuming protocol (−6). We showed that a less time-consuming recording session with light meal intake could be used for the assessment of gastric myoelectrical activity (GMA).

In the era of technological advances and innovations in transportation technologies, application of driving simulators for the investigation and assessment of the driving process provides a safe and suitable testing environment. Although driving simulators are crucial for further improvements in transportation, it is important to resolve one of their main disadvantages&ndash, simulator sickness. Therefore, suitable methods for the assessment of simulator sickness are required. The main aim of this paper was to present a non-invasive method for assessing simulator sickness by recording gastric myoelectrical activity&ndash, electrogastrography. Open-source hardware for electrogastrography together with recordings obtained in 13 healthy volunteers is presented, and the main aspects of signal processing for artifact cancellation and feature extraction were discussed. Based on the obtained results, it was concluded that slow-wave electrical gastric activity can be recorded during driving simulation by following adequate recommendations and that proposed features could be beneficial in describing non-ordinary electrogastrography signals.

The aim of this study was to investigate possible correlation of specific skeletal or dental class in children and adolescents with clinical signs of temporomandibular dysfunction (TMD) with the severity of internal derangement (ID) of the temporomandibular joint.Based on MRI images, the ID of 232 juvenile temporomandibular joints in 116 patients were retrospectively recorded. The distribution of the ID stages within the skeletal and dental classes was compared by means of the χExcluding the comparison between skeletal Class I (S I) and skeletal Class II (S II; p 0.05), no statistically significant differences in the distribution of the ID stages were found between the skeletal classes (p 0.05). No statistically significant differences were found when comparing the distribution of the ID stages between the dental classes (p 0.05).According to these findings, there is no skeletal or dental class that is related to higher degrees of internal derangement in the TMJs of children and adolescents presenting clinical signs of TMD. Therefore, it is not possible to draw conclusions about the severity of the ID in relation to the dental and skeletal class in symptomatic juvenile TMJs.

Numerous studies have been devoted to the causes of craniomandibular dysfunction (CMD). This investigation addressed the effect of class III malocclusion and crossbite on CMD based on a sample of 115 prepubertal and adolescent patients of both sexes. Although class III malocclusion only accounted for 12.2% of the total sample, thus, being the smallest group, the percentage of crossbite (71.4%) among these patients was disproportionately higher than among the other classes. Of the total sample, the prevalence of crossbite was 30.4%. We compared these findings to a large-scale (n=4727) study by Thilander et al. (2002), who reported a strikingly high percentage of class I patients compared to our findings (72.7% versus 27.8%) and a lower percentage of crossbite cases (8.0% versus 30.4%). In accordance with the "orthodontic risk child" concept by Grabowski et al. (2007) and Stahl et al. (2007), we conclude that class III malocclusion and crossbite are keys in the pathogenesis of CMD.

The present case report documents the hitherto unusual application of camouflage orthodontics in one of our patients. Our female patient had previously been treated orthodontically alio loco and had also undergone bimaxillary orthognathic surgery. She presented with TMJ complaints, with associated pains. Despite a dental Class I and centrally seated condyles, her discs had prolapsed anteriorly without reduction and she had developed a massive degenerative-inflammatory TMJ disease. Skeletally, she was a Class II case despite previous orthognathic surgery. In addition, there was also an initial suspicion of rheumatic involvement that could not be confirmed. We distalized the entire lower dental arch without bicuspid extraction. Then we advanced the mandible with the Mandibular Anterior Repositioning Appliance (MARA).We discuss exactly how the modified camouflage therapy was structured and how the individual treatment steps took place.

Occasionally, undesirable post-surgical symptoms of temporomandibular disorder (TMD) and pain have been observed. The aim of this paper is to show how often and to which degree TMJ pathologies occur in orthognathic surgery candidates before surgery, making it recommendable to consider these TMJ pathologies during treatment planning. Between 2002 and 2004, Magnetic Resonance Imaging (MRI) of the TMJ were made in 58 randomly chosen orthognathic surgery patients. 69% of the patients were female, 31% were male. Age averaged 31.6 years (16–61 years). Gender and malocclusion (Class I, II and III) were looked at during analysis of the data (n = 58 patients, n = 116 TMJs). MRI scans were made at the beginning of treatment. We wanted to investigate the TMJ condition before surgery. The largest patients group of this study were the female Class II patients (n = 25). Most patients displayed an Angle Class II (53.4%). The Class III patients followed (32.8%). A Class I molar relationship was found in 13.8% of the studied patients. A similar distribution could be observed in the parameters we studied: 1. condyle (position, degeneration), 2. disc (position, degeneration, prolapse and reduction). 76% of the TMJs (66.7%) showed dorsocranial condylar displacement. 26 of the 114 studied condyles (22.8%) were dorsally displaced. 108 of the studied joints (94.7%) showed condylar displacement. In 31 TMJs (28,4%) we found moderate, in 25 joints (22.9%) severe and in 26 joints (23.9%) we observed slight condylar degeneration. Most discs were displaced ventrally (31%). 22 of the studied 113 discs (19.5%) were displaced medially. 93% of the studied discs were not positioned correctly. 58 of the studied discs (58.6%) displayed flattening, in 8 (8%) we observed both flattening and disc adhesions. Two each of the studied TMJs had discs with perforations and adhesions or only perforations. In 57 (50.4%) of the studied discs we observed partial disc prolapse. Disc prolapse was total in 42.5% (n = 48 TMJs) of the TMJs. Eight TMJs (7%) of the 113 TMJs we analyzed showed no disc prolapse. Disc reduction was total in 71 (62.8%) of the studied TMJs. 15% (n = 17 TMJs) showed a partially reduced disc. 25 (22.1%) of the studied joints showed no disc reduction. Apparently, MRI scans of the TMJ are necessary in almost all potential orthognathic surgery patients to achieve optimal surgical results. Female Class II patients recruited the largest patient group among the studied collective. It is this group that deserves the greatest caution before and after surgery (TMJ pathologies!). In patients with jaw discrepancies, a TMJ examination should be made prior to surgery in order to be able to include the condition of the TMJs in the planning of treatment. This examination best includes Magnetic Resonance Imaging (MRI) and Manual Functional Analysis (MFA).