The Obese Taste Bud study: Objectives and study design.

AIMS: Taste modifies eating behaviour, impacting body weight and potentially obesity development. The Obese Taste Bud (OTB) Study is a prospective cohort study launched in 2020 at the University of Leipzig Obesity Centre in cooperation with the HI-MAG Institute. OTB will test the hypothesis that taste cell homeostasis and taste perception are linked to obesity. Here, we provide the study design, data collection process and baseline characteristics. MATERIALS AND METHODS: Participants presenting overweight, obesity or normal weight undergo taste and smell tests, anthropometric, and taste bud density (TBD) assessment on Day 1. Information on physical and mental health, eating behaviour, physical activity, and dental hygiene are obtained, while biomaterial (saliva, tongue swap, blood) is collected in the fasted state. Further blood samples are taken during a glucose tolerance test. A stool sample is collected at home prior to Day 2, on which a taste bud biopsy follows dental examination. A subsample undergoes functional magnetic resonance imaging while exposed to eating-related cognitive tasks. Follow-up investigations after conventional weight loss interventions and bariatric surgery will be included. RESULTS: Initial results show that glycated haemoglobin levels and age are negatively associated with TBD, while an unfavourable metabolic profile, current dieting, and vegan diet are related to taste perception. Olfactory function negatively correlates with age and high-density lipoprotein cholesterol. CONCLUSION: Initial findings suggest that metabolic alterations are relevant for taste and smell function and TBD. By combining omics data from collected biomaterial with physiological, metabolic and psychological data related to taste perception and eating behaviour, the OTB study aims to strengthen our understanding of taste perception in obesity.

Effects of a disability-simulating learning unit on ableism of final-year dental students - a pilot study.

OBJECTIVES: This study aimed to describe a disability-simulating learning unit (DSLU) to raise dental students' awareness of the special needs of patients with disabilities as well as to measure the effect of the DSLU on ableism. METHODS: A DSLU among final-year undergraduate dental students (n = 33), was developed and evaluated. The students were randomly divided into two groups (Group I, n = 17; Group II, n = 16). Group II only received conventional teaching (control group), whereas Group I was additionally exposed to the DSLU (intervention group). In the DSLU, typical physical restrictions and the associated difficulties in attending dental appointments were simulated with the help of simulation suits. Four different stations offered the opportunity to experience typical signs of disability in a dental context. About 2 months after the DSLU, both groups were asked to answer the Symbolic Ableism Scale (SAS). An analysis was conducted to examine the participants' average total score and several subscores. The Mann-Whitney U Test was employed to control the differences between the study groups. RESULTS: Overall, the students in the intervention group had a significantly (p = .001) lower mean SAS summary score (median = .37; IQR .32-.42) than the students in the control group (median = .50; IQR .39-.53). For the components "individualism" (p < .0001) and "excessive demands" (p = .002) significant group differences could be observed. CONCLUSION: The DSLU is a potentially feasible and effective method for influencing students' ableism attitude.

Acid Resistance of CAD/CAM Resin Composites.

Acid resistance of CAD/CAM resin composites. Erosion-related tooth surface loss is closely related to acid exposure, such as contact with acidic beverages or disease-related reflux. As a result, dental restorations in affected patients are also exposed to acids, which indicates that the performance and longevity of a dental restoration is impacted by the acid resistance of the individually employed restorative materials. However, unlike for ceramic materials, the acid resistance of CAD/CAM resin composites is not commonly evaluated by the manufacturers, and no standardised test methods have yet been established. Against this background, the present in vitro study aimed to examine the long-term resistance of CAD/CAM resin composites (Brilliant Crios, Cerasmart, Grandio blocs, Lava Ultimate, Shofu Block HC) against three acidic media (tonic water, acetic acid, hydrochloric acid) as well as demineralized water and to investigate potential damage mechanisms. Changes in surface roughness (Sa) were detected by confocal laser scanning microscopy (CLSM), and changes in surface hardness were measured using Vickers hardness (HV). The damage mechanisms were analysed by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) and micro X-ray computer tomography (µXCT). For each material, few changes in either Sa or HV were identified for at least one of the different media; for Cerasmart, the sharpest deterioration in surface properties was observed. SEM-EDS revealed leaching of barium, aluminium, and titanium from fillers in a 2 µm zone on the rough but not on the polished surface of the specimen. Within the limitations of the current study, it can be concluded that polished CAD/CAM resin composites can be recommended for clinical use in patients with erosive conditions.

Acid resistance of self-adhesive resin luting cements - changes in surface texture parameters and microhardness.

OBJECTIVES: When consumed in excess, acidic foods and beverages can cause dental erosions leading to irreversible loss of tooth substance. In many cases, prosthetic rehabilitation of the damaged teeth is mandatory. The aim of this in vitro study was to investigate, for the first time on this scale, the resistance of various commonly used self-adhesive resin luting cements (Bifix SE, VOCO; G-Cem LinkAce, GC; RelyX Unicem, 3 M Oral Care; SpeedCEM Plus, Ivoclar ) against acidic media, and to find out whether they can withstand long-term exposure. These results were compared with an adhesive resin luting cement (Panavia V5, Kuraray) that functioned as reference gold standard. Furthermore we applied area roughness parameters for surface texture analysis in the present investigation, to highlight their advantages for investigations on the surface quality of resin luting cements. METHODS: Six specimens with identical diameter (10 mm) and thickness (3 mm) were prepared from each self-adhesive and adhesive resin luting cement and forwarded to an incubation in various acidic media for a period of 232 h. Conductivity and pH-values of each acidic medium was analyzed for each material group prior (t 0) and after exposure (t 1). The specimens were examined for Vickers microhardness and surface quality. For the evaluation of surface roughness, the parameters Sa, Sdr, Spc Spk, Sk, and Svk were investigated by using different filtered surfaces (S-L; S-F) according to ISO 25 178. Statistical analysis was conducted at a significance level of α = 0.050. RESULTS: For the evaluation of the acid resistance of self-adhesive resin luting cements investigations on conductivity and pH-value assessment of storage solution appear unsuitable, while the assessment of microhardness and surface analysis revealed valid data. It could be shown that changes in surface texture of the resin luting cements can be determinend in qualitative and quantitative manner. While the microhardness and surface quality of some resin luting cements hardly changed, others showed significantly reduced values in microhardness and changes in their surface quality (p < 0.001). SIGNIFICANCE: The data of the current study emphasize the relevance of interactions between resin luting cements and acids and suggest further laboratory and clinical studies to elucidate its impact on the clinical performance of the materials investigated.

[How successful can discolored teeth be esthetically restored with monolithic restorative materials - a case report]. / Inwieweit können verfärbte Pfeilerzähne mit monolithischen Restaurationsmaterialien ästhetisch versorgt werden? Ein Fallbericht.

The discoloration of enamel and dentin often has a lasting negative impact on the esthetic appearance. The current clinical case report illustrates which results can be achieved by supplying a patient with restorations fabricated from translucent tooth-colored materials for a traumatically damaged and discolored anterior tooth. A 20-year-old patient sought dental care due to a severe discrepancy in color and shape of tooth 11. As internal bleaching did not reveal a satisfying esthetic outcome, consequently we decided to supply the tooth with a 360° veneer. For material comparisons, the restorations were fabricated from five different monolithic materials. The preparation was performed following the guidelines for 360° veneers, featuring a circular thickness of 0.9 mm. The selected materials included indirect resin composite (Grandio blocs LT, VOCO), feldspathic ceramic (VITABLOCS Mark II LT, VITA Zahnfabrik), leucite-reinforced glass ceramic (IPS Empress CAD LT, Ivoclar Vivadent), lithium disilicate ceramic (IPS e.max CAD LT, Ivoclar Vivadent), and zirconia with 5 mol% yttrium oxide (VITA YZ XT Multicolor LT, VITA Zahnfabrik). The materials were compared for the parameters profitability, esthetics, and patient satisfaction. With a thin layer thickness (0.8-0.9 mm circular), the tooth discoloration could not be adequately covered by any of the 360° veneers. After more extensive preparation, providing a circular thickness of the restoration up to 1.5 mm, all five monolithic materials as well as an additional individually veneered zirconium dioxide crown, serving as a reference, could achieve a satisfactory result. However, the overall esthetic appearance was completely rounded off by the individualized zirconium dioxide crown.

Impact of the DC/TMD instructional video on the practical skills of undergraduate students-A single-blinded, randomized controlled trial.

INTRODUCTION: Competencies in the clinical examination of patients with temporomandibular disorders (TMD) can be achieved by self-instruction. This study aimed to identify the impact of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) instructional video on the practical examination skills of undergraduate students. MATERIALS AND METHODS: One week prior to completing an objective structured clinical examination (OSCE) addressing the examination of patients with TMD, undergraduate students in their third year received either the DC/TMD manual (control group) or additionally watched the instructional video once (intervention group). After passing the OSCE, a feedback questionnaire was completed by the students. RESULT: Fifty undergraduates were recruited to take part in the OSCE prior to their first clinical course. The sum scores achieved in the stations were higher in the intervention group, but missed significance. Participants of the intervention group more often agreed that completing the OSCE stations was easy, which was significant for one station (P = .023). 95.8% of the participating students supported the implementation of the video in dental education. DISCUSSION: Due to the conception of the study, the video was only presented once to ensure that the control group had no access to the medium at all. However, it might be interesting to investigate whether repeated watching of the video enhances its effect. CONCLUSIONS: Clinical competencies in the examination of TMD patients can be achieved by self-instruction with the DC/TMD manual and instructional video. Watching the video for educational purposes was highly recommended by undergraduate students.