Aim This study aimed to evaluate the effect of frozen storage on the physical properties of a silicone-based test food material, highly used to evaluate the masticatory performance in research settings. Methods A total of 1,666 silicone cubes of Optosil Comfort® with 5.6-mm edges were shaped and stored at -18°C. The cubes were subsequently tested for flexural strength (maximum force, displacement, stress, and strain) before breaking (n = 136), changes in weight and size (n = 170), and masticatory performance (n = 1360) at eight timepoints: immediately after cube preparation (baseline, no freezing), and 1, 2, 3 and 4 weeks, and 2, 4 and 6 months after frozen storage. The cubes were thawed 8 h before each assessment. Results The maximum force, stress, maximum displacement, and deformation values for the cubes were not affected by freezing (P > 0.05). At all of the time points, the cubes exhibited similar weight (P = 0.366) and size (identical values). The masticatory performance for the cubes also showed no differences from baseline through 6 months (P = 0.061). Conclusion Freezing Optosil Comfort® silicone cubes did not alter the physical and mechanical properties of the material, being suitable to optimize the assessment of masticatory parameters for research purposes.

Aim This cross-sectional observational study aimed to evaluate the influence of the Universities lockdown measures on academic perspectives and psychosocial aspects of Brazilian final-year dental students. Methods 268 undergraduate students regularly enrolled in a Dentistry course at public universities were asked about anxiety, depression, stress sensitivity, and their academic perspectives by using an online survey. The Hospital Anxiety and Depression Scale (HADS) was used to measure anxiety and depression, while the Perceived Stress Scale (PSS) evaluated stress levels. The academic perspective was evaluated by five affirmatives regarding possible difficulties that will be faced when school reopens and after graduation. The possible association between fear of having COVID-19 with psychosocial outcomes and COVID-19 association with academic perspectives were analyzed by ANOVA and chi-square tests, respectively, considering a significance level of 5%. Results Considering possible associations between the fear of having COVID-19 and psychosocial aspects, significant values were found for anxiety (P = 0.018) and stress sensitivity (P = 0.002). Regarding students’ academic perspectives, COVID-19 had significant impact on less opportunity to perform procedures (P = 0.023), additional expenses with personal protective equipment (P = 0.007), and concerns of consulting elderly people (P = 0.012). Conclusion The COVID-19 pandemic led to increased psychological impairments and enlarged concerns with learning and biosecurity, which might impact academic perspectives. Thus, being aware of these apprehensions, university professors and staff can improve the clinical training of final-year dental students in an empathetic way.

Abstract BoNT-A has been widely used for TMD therapy. However, the potential benefits compared to dry needling techniques are not clear. Objective this study aimed to compare the immediate effects of botulinum toxin type A (BoNT-A) injections and Acupuncture in myofascial temporomandibular disorders (TMD) patients. Methodology 54 women were divided into three groups (n=18). AC patients received four sessions of traditional acupuncture, being one session/week during 20-min. BoNT-A patients were bilaterally injected with 30U and 10U in masseter and anterior temporal muscles, respectively. Moreover, a control group received saline solution (SS) in the same muscles. Self-perceived pain was assessed by visual analog scale, while pressure pain threshold (PPT) was verified by a digital algometer. Electromyographic evaluations (EMG) of anterior temporal and masseter muscles were also measured. All variables were assessed before and 1-month after therapies. The mixed-design two-way repeated measures ANOVA and Tukey’s post-hoc tests were used for analysis, considering a=0.05. Results Self-perceived pain decreased in all groups after one month of therapy (P<.001). BoNT-A was not better than AC in pain reduction (P=0.05), but both therapies were more effective in reducing pain than SS (P<0.05). BoNT-A was the only treatment able to improve PPT values (P<0.05); however, a severe decrease of EMG activity was also found in this group, which is considered an adverse effect. Conclusion after one month of follow-up, all therapies reduced the self-perceived pain in myofascial TMD patients, but only BoNT-A enhanced PPT yet decreased EMG.