Effect of frozen storage on preservation of a silicone-based test food material

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

Academic perspectives and psychosocial aspects of final-year dental students during COVID-19 pandemic

Aim: This cross-sectional observational study aimed to evaluate the influence of the Universities lockdown measures on academic perspectives and psychosocial aspects of Brazilian finalyear 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 chisquare 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

Botulinum toxin type A and acupuncture for masticatory myofascial pain: a randomized clinical trial

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.

Factors associated with oral health-related quality of life of institutionalized elders

Abstract This study aimed to evaluate the correlation between two Oral Health-Related Quality of Life (OHRQoL) questionnaires (the Oral Health Impact Profile (OHIP-14) and the Geriatric Oral Health Assessment Index (GOHAI)) and to investigate the factors associated with the OHRQoL of institutionalized elderly individuals. A cross-sectional multicenter study was performed with 344 institutionalized elderly individuals residing in two Brazilian cities. Six trained researchers interviewed the elderly individuals. Sociodemographic data were collected from medical records. Dental caries experience and the use of and need for dentures were recorded through oral examination performed by two trained examiners. A Likert scale (1-5 points) was used to assess general health and self-perceived oral health. The number of chewing cycles needed to chew a portion of peanuts was used to assess the swallowing threshold. The OHIP-14 and GOHAI were used to evaluate OHRQoL, and statistically significant correlations were assessed using Spearman's correlation test (p < 0.05). Poisson regression (p < 0.05) was used to investigate the association of OHRQoL with independent variables. Scores on the OHIP-14 (7.57 ± 8.63) and GOHAI (32.46 ± 3.85) were strongly and inversely correlated (r2 = -0.671, p < 0.001), although these measures were associated with different factors. A higher OHIP-14 total score (worse OHRQoL) was associated with female gender, a greater number of healthy teeth, worse self-perceived general health and oral health, and a lower swallowing threshold (p < 0.05). A higher GOHAI total score (better OHRQoL) was associated with a greater number of filled teeth, better self-perceived oral health and a greater swallowing threshold (p < 0.05). In conclusion, worse OHRQoL among institutionalized elderly individuals is associated with worse self-perceived oral health and a greater swallowing threshold.

Removable prostheses improve oral health-related quality of life and satisfaction of elderly people with rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease that affects joint tissues and causes severe physical and functional impairments on quality of life due to muscular and articular pain. The involvement of temporomandibular joint in RA interferes with mouth opening and masticatory process. However, no studies addressed the impact of RA on oral health-related quality of life (OHRQoL) and satisfaction with prostheses use in elderly people. Aim: This study assessed the impact of oral rehabilitation with conventional dentures on the OHRQoL and prostheses satisfaction in elderly patients with RA, associated or not with temporomandibular disorder (TMD). Methods: Forty-five elderly were enrolled and divided into three groups: (1) RA and TMD (n=15, experimental), (2) RA without TMD (n=15, experimental), and (3) without RA and without TMD (n=15, control). The OHRQoL and the prostheses satisfaction were evaluated before and after new oral rehabilitation with partial and/or complete dentures. The OHRQoL and prosthesis satisfaction were assessed and verified through OHIP-14 questionnaire and visual analogue scale, respectively. Results: TMD group exhibited the worst mean values (P<0.05) for all OHIP-14 domains before insertion of new dentures. Group 2 showed worst means (P<0.05) compared to controls for functional limitation and physical pain domains of the OHIP-14, but not in the general score. Patients showed better outcomes of satisfaction with prostheses use only after the new rehabilitation. Conclusion: The use of new and well-fitted dentures improves all domains of OHRQoL in patients with RA and TMD and all groups were satisfied with prostheses use after the new rehabilitation with conventional dentures

Mandibular single-implant overdenture as an alternative for full arch rehabilitations: a literature review

Oral rehabilitation with mandibular single-implant overdentures (SIO) has been characterized as a solution to improve retention and stability of conventional complete dentures (CD). Among the benefits of this therapy, it can be mentioned minimally invasive surgery, simple prosthetic technique, better retention, and significantly reduced costs. However, the application of this protocol in daily clinic is still not widespread. Aim: Thus, this study aimed to perform a literature review to address the clinical characteristics of this rehabilitation, when compared to two-implant mandibular overdentures and CD. Methods: For this, a search was conducted in the PubMed database, considering articles published in English language, without date limitation. Results: It was found 243 manuscripts, of which 20 were compatible with the aim of this study after title/abstract reading. The selected papers focused on masticatory muscles function, satisfaction levels and self-reported quality of life, as well as surgical and prosthetic outcomes, such as maintenance, repair and implant failure rates. All evaluated manuscripts showed similar masticatory function and patient's satisfaction with SIO and two-implant overdenture, while results for a SIO were greater when compared to rehabilitations with CD. In addition, SIO have proven to do not damage the implant, being implant loss close to zero. However, the prosthesis fracture adjacent to the implant was a recurrent clinical outcome, which requires further studies to solve this impairment. Conclusion: Thus, it can be concluded that SIO represents an alternative treatment for frail elders or low-income patients, leading to higher masticatory function, as well as improved quality of life

Correlation of mastication and masticatory movements and effect of chewing side preference

The aims of this study were to correlate masticatory performance with mandibular movements during mastication, and to evaluate masticatory performance and mandibular movements of subjects with different types of mastication. Seventy-eight healthy dentate subjects were selected and divided into 2 groups: bilateral and unilateral chewers. This classification was set by using kinesiography during mastication of an artificial material. Unilateral mastication was defined as the majority of the cycles took place at one specific side. The same tracings used to define type of mastication were used to evaluate mandibular movements by means of its parameters. Masticatory performance was analyzed by comminution of the artificial material and a sieving method. Statistical analysis was performed by Spearman’s correlation method, and Mann-Whitney and Studentʼs t-test, when appropriate, at 5 percent significance level. No correlation was found between masticatory performance and parameters of mandibular movement during mastication. Bilateral chewers presented significantly better (p<0.05) masticatory performance than unilateral ones, however no differences in parameters of mandibular movement were found between groups. Within the limits of this study, it may be concluded that parameters of jaw movements during mastication are not related to masticatory performance, and that the presence of a preferred chewing side worsens mastication.

Os objetivos deste estudo foram correlacionar a performance mastigatória com trajetória mandibular durante a mastigação, assim como avaliar performance mastigatória e trajetória mandibular de indivíduos com tipos diferentes de mastigação. Setenta e oito indivíduos saudáveis e dentados foram selecionados e divididos em 2 grupos: mastigação do tipo bilateral e unilateral. Esta classificação foi estabelecida utilizando-se um cinesiógrafo durante a mastigação de um material artificial. A mastigação foi definida como unilateral quando a maioria dos ciclos mastigatórios foi realizada em um lado específico. Os mesmos traçados obtidos para a classificação do tipo de mastigação foram usados para avaliar a trajetória mandibular durante esta função, por meio dos parâmetros do movimento. A performance mastigatória foi analisada pela trituração do material artificial mencionado e um sistema de peneiras. A análise estatística foi determinada pelo método de correlação de Spearman, e pelos testes de Mann-Whitney ou T-Student com nível de significância de 5 por cento. Não foi encontrada correlação entre performance mastigatória e os parâmetros da trajetória mandibular durante a mastigação. Indivíduos com mastigação bilateral apresentaram melhor performance mastigatória do que indivíduos com mastigação unilateral (p<0,05), contudo, os parâmetros da trajetória mandibular não foram diferentes entre os 2 tipos de mastigadores. Nos termos em que este estudo foi conduzido, pode-se concluir que os parâmetros do movimento mandibular durante a mastigação não estão relacionados com a performance mastigatória, que a presença de preferência de lado prejudica a mastigação.