Tumor necrosis factor alpha mediates orofacial discomfort in an occlusal dental interference model in rats: The role of trigeminal ganglion inflammation.

BACKGROUND: Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine that plays an important role in the early stages of inflammation. In this study, we investigated its role in orofacial discomfort in rats subjected to occlusal dental interference (ODI). METHODS: Female Wistar rats (180-200 g) were divided in three groups (n = 30/group): sham group, without ODI, and two experimental groups with ODI pre-treated with 0.1 mL/kg saline (ODI + SAL) or 5 mg/kg infliximab (ODI + INF) and treated every 3 days. The animals were euthanized after 1, 3, and 7 days. The number of bites and scratches and grimace scale scores were determined daily, and the bilateral trigeminal ganglion was histomorphometrically (neuronal body area) analyzed and submitted for immunohistochemistry for TNF-α, nitric oxide synthesis (NOS) neuronal (nNOS) and inducible (iNOS), peroxisome proliferator-activated receptors (PPAR) y (PPARy) and δ/ß (PPARδ/ß), and glial fibrillary acidic protein (GFAP). One-way/two-way ANOVA/Bonferroni tests were used (P < .05, GraphPad Prism 5.0). RESULTS: ODI + SAL showed a large number of bites (P = .002), scratches (P = .002), and grimace scores (P < .001) in the firsts days, and ODI + INF partially reduced these parameters. The contralateral and ipsilateral neuronal body area was significantly reduced on day 1 in ODI + SAL, but returned to the basal size on days 3 and 7, by increase in TNF-α, nNOS, PPARy, PPARδ/ß, and GFAP immunostaining. The infliximab treatment attenuated these alterations (P < .05). There was no iNOS immunostaining. CONCLUSION: Occlusal dental interference induced transitory orofacial discomfort by trigeminal inflammatory mediator overexpression, and TNF-α blockage attenuated these processes.

Conservative management of severe open bite and feeding difficulties in patient with noonan syndrome.

Noonan syndrome is a multiple malformation disorder with an autosomal dominant inheritance pattern. Congenital heart defects, short stature, thoracic deformities, short neck with webbing, hypertelorism, malocclusions, and feeding difficulties are some of the commonly observed clinical features. We report on a case of a patient with Noonan syndrome, severe open bite, associated feeding difficulties, and strong gag reflex, discussing conservative management with myofunctional therapy. Myofunctional therapy has demonstrated a successful outcome, reestablishing masticatory function and routine dental home care after an 18-month follow-up.

Toxicological and genotoxic evaluation of anacardic acid loaded-zein nanoparticles in mice.

Anacardic acid extracted from cashew nut shells of Anacardium occidentale L has demonstrated important biological activities, such as antibacterial activity against the cariogenic specie Streptococcus mutans. Zein nanoparticles containing anacardic acid (9.375 µg/mL) were evaluated in terms of toxicity and genotoxicity in vivo. The subacute toxicity assay was used to evaluate the cumulative effects of the oral administration of nanoencapsulated anacardic acid at 2.25 and 112.5 µg/kg for 7 days in mice, simulating a mouth rinse short-term clinical course treatment. Blank zein nanoparticles and saline solution 0.9 % were used as negative controls. Peripheral blood samples were collected to evaluate the genotoxicity in polychromatic erythrocytes using the micronucleus test. The animals were anesthetized, euthanized and the target organs collected, weighed and submitted to histopathological analysis. Liver, kidney and spleen relative weights did not change. Nevertheless, stomach, lung and heart increased the relative weights in the group receiving the highest dose, in which occasional histopathological findings were also identified. Both doses maintained the micronucleus frequency within the normal range and the animals treated with the highest dose presented a discrete weight lost, which could explain the organs' relative weight reductions. Blank and anacardic acid loaded zein nanoparticles were nontoxic when administered repeatedly for 7 days, as no relevant histopathological changes neither genotoxicity were observed. These preparations demonstrated limited toxicity under the conditions used in this study and could become an antibacterial alternative for preventing/treating oral infections in short-term treatments.

Photobiomodulation and antimicrobial photodynamic therapy as adjunct in the treatment and prevention of osteoradionecrosis of the jaws: A case report.

CASE REPORT: We report on a patient with a history of radiotherapy to the head and neck region exhibiting necrotic bone exposure associated with fistula and purulent exudation in the mandible, with the diagnosis of stage 3 osteoradionecrosis, in addition to a periapical cyst in the maxillary anterior region and multiple root remnants. An antibiotic coverage protocol with amoxicillin and metronidazole was prescribed for subsequent necrotic bone removal. The surgical procedure was performed along with the aPDT using methylene blue and red light, followed by coaptation of the edges of the surgical wound and the healing protocol with LLLT. The extraction of non-rehabilitated teeth was performed two per session using antibiotic coverage, aPDT, and LLLT and mouthwash with 0.12 % chlorhexidine was prescribed until the complete closure of the surgical wound was achieved. Additionally, two aPDT sessions and four LLLT protocols were performed for complete healing of the surgical sites. Extra and intraoral examinations and panoramic and periapical radiographs were performed. No emergence or recurrence of osteonecrosis was observed after 12 months of follow-up.

Effect of Photodynamic Antimicrobial Chemotherapy on Mono- and Multi-Species Cariogenic Biofilms: A Literature Review.

OBJECTIVE: The aim of this literature review is to study the effect of photodynamic antimicrobial chemotherapy (PACT) on mono- and multi-species cariogenic biofilms. METHODS: To this purpose, the database, PubMed, was searched using the descriptors, photodynamic therapy, antimicrobial photodynamic chemotherapy, and photoinactivation, associated with the mandatory presence of the word biofilm. A total of 98 references published from 2003 to 2016 were selected. Moreover, literature reviews (15), investigations that did not have biofilms related to dental caries (65), and those that did not have Streptococcus mutans count as an outcome (7) were excluded, yielding a final amount of 11 publications. RESULTS: The results revealed that Toluidine Blue O was the most used photosensitizer. Among the sources of light, light-emitting diode was the choice, and the biofilm models varied between in vitro and in situ. Multi-species biofilms were more resistant to the antimicrobial effects of PACT due to the thickness and complexity they have, which impede the penetration of the photosensitizer. This fact may also be associated with the type of photosensitizer used as well as with the light exposure time since the antimicrobial effect seems to be dose dependent. Despite this, in all the included publications, the therapy was effective in reducing S. mutans count. CONCLUSIONS: This review demonstrated that under different conditions, PACT is effective in reducing S. mutans count in monospecies biofilms. Multi-species biofilms were more resistant to the antimicrobial action of the therapy, possibly due to their thickness and complexity.

Technology acceptance by professors and adherence of undergraduate dental students to virtual classes during COVID-19 pandemic / Aceitação de tecnologia por professores e adesão de alunos de graduação em Odontologia a aulas virtuais durante a pandemia COVID-19

The aim of this study wastoanalyse the acceptance of technology by professors and the adherence of dental students to virtual teachingduring the social distancing period due to the coronavirus disease (COVID-19) pandemic. This was a retrospective observational cross-sectional study that involved the anonymous opinion of dental schoolprofessors. After each virtual class, the professorsfilled out the e-questionnaire aboutthe remote activities(discipline identification, method used, number of students, satisfaction of the professor, and a technology acceptance model questionnaire) performed between 18 March and 18 May (60 days of virtualisation of theoretical classes during interruption of face-to-face classes). This study showed a good acceptability of this learning technologyby professors(TAM score 81.82 ± 11.79). During the pandemic, live video conferencing classes (n = 632, 63.6%) were the most preferred method of teachingby professors, followed by previously recorded video lessons (n = 403, 40.5%). Theacceptability of professors was strongly associated with the perception of the quality of interaction (p <0.001).Higherstudentparticipation was significantly associated with live videoconference classes (p = 0.019).Prioravailability of articles or documents for study (p = 0.028)andthe absence of technological complications during the virtual classes (p = 0.003)significantly increased acceptability.In conclusion, the virtual class technology usedduring the COVID-19pandemic period was well accepted by professors at a dental school and had good adherence by students, especially in videoconferencing classes (AU).

O objetivo deste estudo foi analisar a aceitação da tecnologia por professores e a adesão dos alunos de odontologia ao ensino virtual durante o período de distanciamento social devido à pandemia do coronavírus (COVID-19). Este foi um estudo transversal observacional retrospectivo que envolveu a opinião anônima de professores de escolasde odontologia. Após cada aula virtual, os professores preencheram um questionário sobre as atividades remotas (identificação da disciplina, método utilizado, número de alunos, satisfação do professor e questionário do modelo de aceitação de tecnologia) realizado entre 18 de março e 18 de maio (60 dias de virtualização das aulas teóricas durante a interrupção das aulas presenciais). Este estudo mostrou uma boa aceitabilidade desta tecnologia de aprendizagem pelos professores (pontuação TAM 81,82 ± 11,79). Durante a pandemia, aulas de videoconferência ao vivo (n = 632, 63,6%) foram o método de ensino preferido pelos professores, seguido por vídeo aulas previamente gravadas (n = 403, 40,5%). A aceitabilidade dos professores esteve fortemente associada à percepção da qualidade da interação (p <0,001). A maior participação dos alunos foi significativamente associada às aulas de videoconferência (p = 0,019). A disponibilidade prévia de artigos ou documentos para estudo (p = 0,028) e a ausência de complicações tecnológicas durante as aulas virtuais (p = 0,003) aumentaram significativamente a aceitabilidade. Concluindo, a tecnologia da aula virtual usada durante o período pandêmico do COVID-19 foi bem aceita pelos professores de uma faculdade de odontologia e teve boa aderência dos alunos, principalmente nas aulas de videoconferência (AU).

Ação do laser infravermelho em suspensões de Streptococcus mutans / Infrared laser action on Streptococcus mutans suspensions

Introdução: os benefícios do laser infravermelho no tratamento da mucosite oral e no controle da dor na disfunção da articulação temporomandibular são bem reconhecidos e já aplicados clinicamente. Porém, o efeito dessa terapia em bactérias da cavidade oral ainda é incerto. Objetivo: analisar o efeito do laser infravermelho Diodo de Arseneto de Gálio Alumínio (AsGaAl) (LIV) nos níveis de suspensões de Streptococcus mutans UA159. Método: o laser de baixa potência infravermelho e comprimento de onda predominante de 880nm (Therapy XT-ESTM, DMC Equipamentos) foi utilizado com potência de 100mW e diâmetro da ponteira 0,0280 cm². A suspensão bacteriana foi ativada em estufa bacteriológica a 37ºC e 5% CO2, durante um período de 18 horas, ajustada para a concentração de 1-2 x 108 unidades formadoras de colônia/mL (UFC/mL). As suspensões foram submetidas aos seguintes protocolos experimentais e controle: grupo 1) LIV 30s; grupo 2) LIV 60s; grupo 3) LIV 90s; grupo 4) NaCl 0,9%. Em seguida, uma alíquota foi retirada para a diluição seriada e semeadura das amostras. As placas permaneceram em estufa bacteriológica a 37ºC e 5% CO2 durante um período de 48 horas para posterior contagem das UFC/mL. O estudo foi conduzido em triplicata. Resultados: os resultados, a seguir, estão expressos em Log UFC/mL: grupo 1 (8,42±0,16); grupo 2 (8,41±0,03); grupo 3 (8,37±0,11); grupo 4 (8,37±0,16). Não foi observada diferença estatisticamente entre os grupos (p>0,05). Conclusão: o estudo mostrou que o laser infravermelho, nas condições experimentais usadas, não demonstrou ação na viabilidade de S. mutans presentes em suspensões in vitro.

Introduction: The benefits of infrared laser in the treatment of oral mucositis and pain control in temporomandibular joint dysfunction are well recognized and applied clinically. However, the effect of this therapy on oral cavity bacteria is still uncertain. Objective: Analyze the effect of infrared laser Gallium Arsenide Diode (AsGaAl) (LIV) on the levels of Streptococcus mutans UA159 suspensions. Method: Low-power infrared laser with predominant wavelength of 880nm (Therapy XT-ESTM, DMC Equipment) was used with 100mW output power and tip diameter 0.0280cm².The bacterial suspension was activated in a bacteriological oven at 37 ° C and 5% CO 2 for a period of 18 h, adjusted to the concentration of 1-2 x 108 colony forming units / mL (CFU / mL).The suspensions were submitted to the following experimental protocols and control: Group 1)LIV 30s; group 2)LIV 60s; Group 3)LIV 90s; Group 4)saline solution. After that, an aliquot was taken for serial dilution and plating of the sample. The plates were kept in a bacteriological oven at 37°C and 5% CO2 for 48 hours for subsequent cfu/ml counts. The study was conducted in triplicates. Results: The following results are expressed in Log ufc/mL: Group 1 (8.42 ± 0.16); Group 2 (8.41 ± 0.03); Group 3 (8.37 ± 0.11); Group 4 (8.37 ± 0.16). There was no statistically significant difference between groups (p>0.05). Conclusion: In the experimental tested conditions, the study showed that the infrared laser had no action on the viability of S. mutans suspensions in vitro.