The effects of re-irradiation on the chemical and morphological properties of permanent teeth.

This study aimed to assess the in vitro effects of re-irradiation on enamel and dentin properties, simulating head and neck cancer radiotherapy retreatment. Forty-five human permanent molars were classified into five groups: non-irradiated; irradiated 60 Gy, and re-irradiated with doses of 30, 40, and 50 Gy. Raman spectroscopy, scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS) were employed for analysis. Raman spectroscopy assessed intensity, spectral area, and specific peaks comparatively. Statistical analysis involved Kolmogorov-Smirnov and One-Way ANOVA tests, with Tukey's post-test (significance level set at 5%). Significant changes in irradiated, non-irradiated, and re-irradiated enamel peaks were observed, including phosphate (438 nm), hydroxyapatite (582 nm), phosphate (960 nm), and carbonate (1070 nm) (p < 0.05). Re-irradiation affected the entire tooth (p > 0.05), leading to interprismatic region degradation, enamel prism destruction, and hydroxyapatite crystal damage. Dentin exhibited tubule obliteration, crack formation, and progressive collagen fiber fragmentation. EDX revealed increased oxygen percentage and decreased phosphorus and calcium post-reirradiation. It is concluded that chemical and morphological changes in irradiated permanent teeth were dose-dependent, exacerbated by re-irradiation, causing substantial damage in enamel and dentin.

Optical coherence tomography and gray scale digital analysis as noninvasive techniques for evaluating molar-incisor hypomineralization severity: A comparative study with microcomputed tomography.

Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel characterized by demarcated opacities present in permanent first molars and other teeth. It is considered a major clinical challenge in dentistry because it makes affected teeth more susceptible to fractures and dental caries. Its diagnosis is mainly clinical and there are few technological resources that allow for a more accurate diagnosis, especially with respect to the depth of the defect in the dental enamel. In this context, optical coherence tomography (OCT), which is routinely used in ophthalmology, can produce images of the depth of the dental enamel, making it a promising method. In this study, 33 teeth with different MIH severities were evaluated using OCT and microcomputed tomography (microCT). Semi-quantitative methods of grayscale pattern analysis were used to compare images obtained from different severities of MIH with the mineral density obtained through microCT. MicroCT evaluation revealed that hypomineralized enamel had a significantly lower mineral density than intact enamel. However, this difference was not observed between the mild and severe MIH lesions. In the OCT evaluation, significant differences were observed between the intact and hypomineralized enamel, and the gray value comparison provided a method for quantitative differentiation between the two. This study suggests that OCT could be a useful adjunct to traditional diagnostic methods for MIH, offering a noninvasive approach to evaluate enamel defects. RESEARCH HIGHLIGHTS: Combining optical coherence tomography with grayscale digital analysis shows potential as a promising method for diagnosing molar-incisor hypomineralization and assessing its level of severity.

Activation of gelatinases in permanent human teeth after different experimental radiotherapy protocols.

The objective of this study was to compare the activation of gelatinases in dentin-enamel junction (DEJ) and underlying dentin of permanent teeth after experimental radiotherapy in conventional and hypofractionated modalities. Newly extracted third molars (n = 15) were divided into three experimental radiotherapy groups: control, conventional (CR), and hypofractionated (HR) (n = 5 per group). After in vitro exposure to ionizing radiation, following standardized protocols for each modality, a gelatinous substrate was incubated on the tooth slices (n = 10 per group). Activation of gelatinases was measured by in situ zymography, expressed in arbitrary fluorescence units (mm2) from three tooth regions: cervical, cuspal, and pit. Fluorescence intensity was compared among radiotherapy protocols and tooth regions in each protocol, considering a significance level of 5%. Considering all tooth regions, the fluorescence intensity of the CR group was higher than the HR and control groups, both in DEJ and underlying dentin (p <0.001). In addition, the fluorescence intensity was higher in underlying dentin when compared to DEJ in all groups (p <0.001). Considering each tooth region, a statistically significant difference between CR and HR was only observed in the pit region of underlying dentin (p <0.001). Significant and positive correlations between fluorescence intensities in DEJ and underlying dentin were also observed (p <0.001). Experimental radiotherapy influenced the activation of gelatinases, as well as exposure to the conventional protocol can trigger a higher activation of gelatinases when compared to hypofractionated, both in DEJ and underlying dentin.

Use of Optical Coherence Tomography for Differential Diagnosis of Severity of Molar Incisor Hypomineralization (MIH).

Purpose: To evaluate descriptively and quantitatively teeth affected by enamel hypomineralization (EH) using optical coherence microtomography (OCT). Methods: Twenty teeth were classified according to the European Academy of Pediatric Dentistry's molar incisor hypomineralization (MIH) index and separated into groups according to the degree of EH severity. For each tooth, scans were performed on both the affected and the non-affected areas, and their corresponding optical images were captured. Results: In the qualitative analyses, in most of the images bright lines were observed in relation to the enamel surface and a high level of photon scattering immediately below the enamel surface. This showed that the shading distribution can be identified as hypomineralized areas in which the scattering signal can be used as a diagnostic criterion. In the quantitative analyses, Tukey's test was performed to evaluate the means of the optical attenuation coefficient, which did not present significant differences. However, considering the correlation, homogeneity and contrast analyses, a statistically significant difference was observed between the groups. The group with severe MIH showed greater homogeneity and correlation, but less contrast. Conclusion: Currently, MIH has its severity measured by essentially clinical means. OCT processing techniques reveal advances in the diagnostic imaging of MIH, showing that image texture analysis can be a promising and useful method to aid in its diagnosis.

Conhecimento e repercussões emocionais da COVID-19 entre estudantes de Odontologia brasileiros / Conocimientos y repercusiones emocionales de la COVID-19 entre estudiantes brasileños de odontología / Knowledge about and emotional impact of COVID-19 among Brazilian dental students

Em decorrência da pandemia de COVID-19, implementou-se atividades remotas de ensino, como medida de distanciamento social. O objetivo deste estudo foi avaliar o conhecimento dos graduandos de Odontologia brasileiros sobre a COVID-19, bem como o possível impacto da pandemia nas condições emocionais e sociais destes estudantes. Trata-se de um estudo transversal com coleta de dados primários, por meio de questionário estruturado. O questionário ficou vigente no período de 11 de agosto a 11 de setembro de 2020, com envios semanais, com amostragem de conveniência. Os dados foram submetidos à análise descritiva. A pesquisa abrangeu discentes doprimeiro ao décimo período do curso de Odontologia, das diferentes regiões brasileiras. Foram coletadas 520 respostas, de 14 estados do país. Os alunos demonstraram ter um alto nível de conhecimento sobre a COVID-19, 77,31% não se sentiam seguros, 85,96% alegaram medo em relação ao futuro e 96,15% afirmaram ter havido prejuízos no seu curso de graduação. Dentre os alunos, 69,56% relataram piora no estado emocional, 83,08% perceberam-se mais estressados, 58,46% afirmaram ter desenvolvido insônia e 51,25% afirmaram que a pandemia afetou negativamente as finanças familiares. Conclui-se que os graduandos de Odontologia brasileiros têm conhecimento sobre a COVID-19 e a pandemia os afetou negativamente em relação aos aspectos emocionais e sociais (AU).

A raíz de la pandemia del COVID-19, se implementaron actividades de enseñanza a distancia como medida de distanciamiento social. El objetivo de este estudio fue evaluar el conocimiento de los estudiantes brasileños de odontología sobre el COVID-19, así como el posible impacto de la pandemia en las condiciones emocionales ysociales de estos estudiantes. Se trata de un estudio transversal con recogida de datos primarios a través de un cuestionario estructurado. El cuestionario estuvo vigente del 11 de agosto al 11 de septiembre de 2020, con envíos semanales, con muestreo porconveniencia. Los datos fueron sometidos a análisis descriptivo. La investigación abarcó estudiantes del primero al décimo período de la carrera de Odontología, de diferentes regiones brasileñas. Se recogieron 520 respuestas de 14 estados del país. Los estudiantes demostraron un alto nivel de conocimiento sobre el COVID-19, el 77,31 % no se sentía seguro, el 85,96 % manifestó tener miedo al futuro y el 96,15 % manifestó haber tenido pérdidas en su carrera de grado. Entre los estudiantes, el 69,56 % reportóun empeoramiento en su estado emocional, el 83,08 % se sintió más estresado, el 58,46 % dijo haber desarrollado insomnio y el 51,25 % dijo que la pandemia tuvo un efecto negativo en la economía familiar. Se concluye que los estudiantes de odontología brasileños son conscientes de la COVID-19 y la pandemia los ha afectado negativamente en los aspectos emocionales y sociales (AU).

As a result of the COVID-19 pandemic, remote teaching activities have been implemented as a social distancing measure. The objective of this study was to assess the knowledge that Brazilian dental students have about COVID-19, as well as the possible impact of the pandemic on these students' emotional and social conditions. This is a cross-sectional study using primary-data collection by means of a structured questionnaire. The latter was open from August 11 to September 11, 2020, with weekly submissions, and with convenience sampling. Data were subjected to descriptive analysis. The research included students attending the first to the tenth period of Dentistry courses, from different Brazilian regions. A total of 520 responses were collected from 14 statesin the country. The students proved to have a high level of knowledge about COVID-19; 77.31% did not feel safe, 85.96% claimed to be afraid of the future, and 96.15% stated that their undergraduate courses went through losses. Moreover, 69.56% reported a worsening in their emotional state, 83.08% perceived themselves as being more stressed, 58.46% said they developed insomnia, and 51.25% stated that the pandemic had a negative effect on family finances. It is concluded that Brazilian dental students have knowledge about COVID-19, and the pandemic has negatively affected them in terms of emotional and social aspects (AU).

Electromyographic analysis of the stomatognathic system of children with Molar-incisor hypomineralization.

INTRODUCTION: Molar-incisor hypomineralization (MIH) is a qualitative defect of dental enamel that affects one or more permanent first molars, with or without involvement of the incisor teeth. This condition leads to challenges to dental care and treatment planning. AIM: Based on the hypothesis that children who have MIH possibly present alterations in postural and masticatory activities and considering the absence of studies investigating these parameters, the present study evaluated the functionality of the stomatognathic system considering the mentioned aspects. MATERIALS: The comparison of individuals with (MIHG; n = 32) and without MIH (CG; n = 32) was evaluated by electromyographic activity of the masseter and temporal muscles (right and left), as well as evaluation of the masticatory cycles during habitual mastication. RESULTS: MIHG showed muscle hyperactivity in postural and dynamic conditions compared to the CG; higher electromyographic values for MIHG when compared to CG in the following postural conditions: at rest for the right temporal (p = 0.00) and left temporal muscles (p = 0.03); in the protrusion to the right temporal muscle (p = 0.02); in the right laterality for the right masseter (p = 0.00) and left temporal muscles (p = 0.01); in the left laterality for the right masseter (p = 0.03) and left temporal (p = 0.04) muscles. In dynamic conditions with consistent food, significance was observed for the left temporal (p = 0.01); and with soft food for the right (p = 0.01) and left temporal muscles (p = 0.04). CONCLUSIONS: Children with MIH seem to have impaired functionality of the stomatognathic system. Children with MIH have alterations in the stomatognathic system.

Auriculotherapy in a patient with Arnold Chiari malformation type II: Case report.

AIMS: Auriculotherapy is a therapeutic method of traditional Chinese Medicine in which a stimulus is exerted on the ear and activates energy channels throughout the body, helping to control anxiety, stress, pain, inflammation, illnesses chronic, and possibly can be used in patient with Arnold Chiari Malformation type II who have painful symptoms that are difficult to resolve. Thus, the aim of this article is to present a case in a patient with Chiari Malformation II where auriculotherapy and effect of laser therapy were performed, to relieve symptoms of agitation, anxiety and healing of self-mutilation injuries. CASE REPORT: Data from medical records were used to collect medical and dental history, complaints and treatments performed. Eight sessions of auriculotherapy and one of laser therapy were carried out in order to heal the lesions. The patient presented lower levels of anxiety, agitation and ceased the habit of self-mutilation and, consequently, the pain. CONCLUSIONS: The use of auriculotherapy led to a considerable improvement in the patient's painful condition and reduced anxiety, also benefiting the interaction with her family members and laser therapy promoted wound healing.

Silver nanoparticles in mouthwashes against infection caused by SARS-CoV-2: a scoping review / Nanopartículas de prata em enxaguatórios bucais para uso em infecções por SARS-CoV-2: uma revisão de escopo

The Silver nanoparticle (AgNPs) have received attention for their antiviral potential against SARS-CoV-2. The objective is to conduct a scope review and map the scientific evidence on the use of AgNPs in mouthwashes as an adjunct in decreasing the viral load in the oral cavity of patients with SARS-CoV-2. A search was performed in the PubMed, Medline, Scielo databases, and a manual search in the reference lists, following the standards of the Joanna Briggs Institute for Scoping Review without restriction of year, language or sample size. Thus, 14 articles were included, where they researched the use of AgNPs with antiviral effect against SARS-CoV-2, mouthwashes for SARS-CoV-2 and AgNPs as mouthwashes. We can suggest that AgNPs are likely antiviral therapies for SARS-CoV-2 and its use in mouthwashes associated with other therapies are promising strands for decreasing viral load and infection by the vírus (AU)

As nanopartículas de prata (AgNPs) têm recebido atenção por seu potencial antiviral no SARS-CoV-2. O objetivo deste trabalho é realizar uma revisão de escopo e mapear as evidências científicas sobre o uso de AgNPs em bochechos como adjuvante na diminuição da carga viral na cavidade oral de pacientes com SARS-CoV-2. Foi realizada busca nas bases de dados PubMed, Medline, Scielo e busca manual nas listas de referências, seguindo os padrões do Joanna Briggs Institute for Scoping Review sem restrição de ano, idioma ou tamanho da amostra. Assim, foram incluídos 14 artigos, onde pesquisaram o uso de AgNPs com efeito antiviral contra SARS-CoV-2, enxaguatórios bucais para SARS-CoV-2 e AgNPs como enxaguatórios bucais, vertentes promissoras para diminuição da carga viral e infecção pelo vírus.(AU)

Activation of gelatinases in permanent human teeth after different experimental radiotherapy protocols

Abstract The objective of this study was to compare the activation of gelatinases in dentin-enamel junction (DEJ) and underlying dentin of permanent teeth after experimental radiotherapy in conventional and hypofractionated modalities. Newly extracted third molars (n = 15) were divided into three experimental radiotherapy groups: control, conventional (CR), and hypofractionated (HR) (n = 5 per group). After in vitro exposure to ionizing radiation, following standardized protocols for each modality, a gelatinous substrate was incubated on the tooth slices (n = 10 per group). Activation of gelatinases was measured by in situ zymography, expressed in arbitrary fluorescence units (mm2) from three tooth regions: cervical, cuspal, and pit. Fluorescence intensity was compared among radiotherapy protocols and tooth regions in each protocol, considering a significance level of 5%. Considering all tooth regions, the fluorescence intensity of the CR group was higher than the HR and control groups, both in DEJ and underlying dentin (p <0.001). In addition, the fluorescence intensity was higher in underlying dentin when compared to DEJ in all groups (p <0.001). Considering each tooth region, a statistically significant difference between CR and HR was only observed in the pit region of underlying dentin (p <0.001). Significant and positive correlations between fluorescence intensities in DEJ and underlying dentin were also observed (p <0.001). Experimental radiotherapy influenced the activation of gelatinases, as well as exposure to the conventional protocol can trigger a higher activation of gelatinases when compared to hypofractionated, both in DEJ and underlying dentin.

Resumo O objetivo deste estudo foi comparar a ativação de gelatinases na junção dentina-esmalte (DEJ) e na dentina subjacente de dentes permanentes após a radioterapia experimental nas modalidades convencional e hipofracionada. Os terceiros molares recém-extraídos (n = 15) foram divididos em três grupos de radioterapia experimental: controle, convencional (CR) e hipofracionada (HR) (n = 5 por grupo). Após a exposição in vitro à radiação ionizante, seguindo protocolos padronizados para cada modalidade, um substrato gelatinoso foi incubado nas fatias de dente (n = 10 por grupo). A ativação das gelatinases foi medida por zimografia in situ, expressa em unidades arbitrárias de fluorescência (mm2) de três regiões do dente: cervical, cúspide e fossa. A intensidade da fluorescência foi comparada entre os protocolos de radioterapia e as regiões do dente em cada protocolo, considerando um nível de significância de 5%. Considerando todas as regiões do dente, a intensidade de fluorescência do grupo CR foi maior do que a dos grupos HR e controle, tanto no DEJ quanto na dentina subjacente (p <0,001). Além disso, a intensidade da fluorescência foi maior na dentina subjacente quando comparada à DEJ em todos os grupos (p <0,001). Considerando cada região do dente, uma diferença estatisticamente significativa entre CR e HR foi observada apenas na região da fossa da dentina subjacente (p <0,001). Também foram observadas correlações significativas e positivas entre as intensidades de fluorescência no DEJ e na dentina subjacente (p <0,001). A radioterapia experimental influenciou a ativação das gelatinases, assim como a exposição ao protocolo convencional pode desencadear uma maior ativação das gelatinases quando comparada ao hipofracionamento, tanto no DEJ quanto na dentina subjacente.

Use of Images and Clinical Experience to Calibrate Dental Surgeons for the Diagnosis of Molar Incisor Hypomineralization

ABSTRACT Objective: To evaluate an imaging protocol for use as a diagnostic and calibration tool for dentists before and after practical activity. Material and Methods: Thirty photos of children's teeth with or without changes in dental enamel were selected and evaluated by a group of experienced dentists previously calibrated to establish the diagnosis defined as the gold standard. After instructions, the images were shown to a group of postgraduate dentists for free identification of dental changes. Subsequently, a lecture on molar incisor hypomineralization (MIH) was carried out, and, at 14 days and all calibration was performed using the criteria previously. The retest was performed at 28 days. After experience in clinical activity in the following two weeks, the post-test was performed at 49 days. Data were analyzed using Cohen's kappa coefficient. Results: Theoretical learning on the subject showed low inter-examiner agreement when the diagnosis of defects was made from images obtained from intraoral photographs. After clinical practice, there was greater intra-examiner agreement. After theoretical training, dentists started to identify different types of enamel alteration, although with low agreement between them. Conclusion: Clinical experience in theoretical and imaging training favored the identification of defects. However, it is necessary to improve the protocol to establish a reliable and viable diagnostic method for calibration in MIH.

Use of Restorative Materials in Primary Teeth - A Retrospective University-Based Study

ABSTRACT Objective: To investigate the types of restorative materials used for restorative treatment in primary teeth through a retrospective university-based study. Material and Methods: The sample consisted of all clinical records of children attended at the Pediatric Dentistry Clinic at the School of Dentistry of Ribeirão Preto at the University of São Paulo in Brazil. Inclusion criteria were primary anterior and posterior teeth that received dental restorations for treatment of dental caries lesions, dental trauma or dental development defects from 2013 to 2018. Restoration repairs and interim restorations during this period were also recorded. Descriptive analyzes were performed to assess the distribution according to the type of restorative material used over the years. Results: A total of 5,236 restorative procedures were performed in primary teeth, including restoration repair and interim restorations. Of those, 69% were done in posterior teeth and 31% in anterior teeth. Sixty percent of the procedures performed during this period were made of composite resin and a lower percentage of glass ionomer cement (18%) followed by silver amalgam (1%). The number of interim restorations was smaller but proportional to those of composite resin over the years. Conclusion: A tendency to carry out restorative treatment of primary teeth with composite resin during the 6 years of follow-up was observed.

Adhesion of a sealant with pre-reacted glass ionomer particles under salivary contamination: an in vitro study

Objective: this in vitro study compared the adhesive strengths of the resin sealant with the Giomer technology sealant under salivary contamination. Materials and Methods: fifty-two bovine incisors were randomly divided into four groups (n=13): GI, a resin sealant (Fluroshield®) without salivary contamination (control of GII); GII, Fluroshield sealant + salivary contamination; GIII, a Giomer technology sealant (BeautiSealant®) without salivary contamination (control of GIV); and GIV, BeautiSealant® sealant + salivary contamination. In the salivary contamination groups, artificial saliva was used through a pipette, and after 20 s, it was air-dried and the sealant was applied. Shear strength tests were performed using a universal testing machine. One-way ANOVA variance and Tukey's test were used for multiple comparisons. The fracture types were analyzed using a stereomicroscope with 40X magnification. Results: the means and standard deviations (SD) of adhesion for Fluroshield® and BeautiSealant® in the group without salivary contamination were 15.27 (±0.96) and 11.90 (±0.94), and for the group with salivary contamination, 13.14 (±1.03) and 8.95 (±1.33), respectively, indicating a statistically significant difference between GI and GII p=0.020, GIII and GIV p=0.041. Mixed failures were detected in GI (38%), GII (44%), GIII (38%), and GIV (62%). Conclusion: there was a statistically significant decrease in the adhesive strength values in the groups with salivary contamination for both the sealants studied. However, no significant difference was observed between the two sealants when the materials used were compared.

Objetivo: este estudo in vitro comparou as forças adesivas do selante resinoso com o selante da tecnologia Giomer sob contaminação salivar. Materiais e Métodos: cinquenta e dois incisivos bovinos foram divididos aleatoriamente em quatro grupos (n=13): GI, um selante resinoso (Fluroshield®) sem contaminação salivar (controle do GII); GII, selante Fluroshield + contaminação salivar; GIII, um selante com tecnologia Giomer (BeautiSealant®) sem contaminação salivar (controle do GIV); e GIV, selante BeautiSealant® + contaminação salivar. Nos grupos de contaminação salivar, a saliva artificial foi utilizada por meio de uma pipeta e, após 20 s, foi seca ao ar e aplicado o selante. Os testes de resistência ao cisalhamento foram realizados usando uma máquina de teste universal. A variância ANOVA de uma via e o teste de Tukey foram usados para comparações múltiplas. Os tipos de fratura foram analisados em estereomicroscópio com aumento de 40X. Resultados: as médias e desvios padrão (DP) de adesão para Fluroshield® e BeautiSealant® no grupo sem contaminação salivar foram 15,27 (±0,96) e 11,90 (±0,94), e após contaminação salivar foram 13,14 (±1,03) e 8,95 (±1,33), respectivamente, indicando haver diferença estatisticamente significante entre GI e GII p=0.020, GIII e GIV p=0.041. Falhas mistas foram detectadas em GI (38%), GII (44%), GIII (38%) e GIV (62%). Conclusão: houve diminuição estatisticamente significativa dos valores de resistência adesiva nos grupos com contaminação salivar para ambos os selantes estudados. No entanto, não foi observada diferença significativa entre os dois selantes quando comparados os materiais utilizados.

Leukotriene B4 Loaded in Microspheres Inhibits Osteoclast Differentiation and Activation.

To investigate osteoclast formation in vivo and if leukotriene B4 (LTB4) loaded in microspheres (MS) could be used as a therapeutical strategy to promote a sustained delivery of the mediator and prevent osteoclast differentiation. Methods: In vivo, apical periodontitis was induced in mice to investigate osteoclast differentiation and signaling in absence of 5-lipoxygenase (5-LO). In vitro, LTB4-MS were prepared using an oil-in-water emulsion solvent extraction-evaporation process. Characterization and efficiency of LTB4 encapsulation were investigated. J774A.1 macrophages were cultured in the presence of monocyte colony-stimulating factor (M-CSF) and ligand for receptor activator of nuclear factor kappa B (RANKL) and then stimulated with LTB4-MS. Cytotoxicity, in vitro MS-LTB4 uptake, osteoclast formation and gene expression were measured. Results: We found that 5-LO negatively regulates osteoclastic formation in vivo during apical periodontitis development. In vitro, LTB4-MS were up-taken by macrophages and were not cytotoxic to the cells. LTB4-MS inhibited osteoclast formation and the synthesis of osteoclastogenic genes Acp5, Mmp9, Calcr and Ctsk. LTB4-MS inhibited differentiation of macrophages into an osteoclastic phenotype and cell activation under M-CSF and RANKL stimulus.

Leukotriene B4 Loaded in Microspheres Inhibits Osteoclast Differentiation and Activation

Abstract To investigate osteoclast formation in vivo and if leukotriene B4 (LTB4) loaded in microspheres (MS) could be used as a therapeutical strategy to promote a sustained delivery of the mediator and prevent osteoclast differentiation. Methods: In vivo, apical periodontitis was induced in mice to investigate osteoclast differentiation and signaling in absence of 5-lipoxygenase (5-LO). In vitro, LTB4-MS were prepared using an oil-in-water emulsion solvent extraction-evaporation process. Characterization and efficiency of LTB4 encapsulation were investigated. J774A.1 macrophages were cultured in the presence of monocyte colony-stimulating factor (M-CSF) and ligand for receptor activator of nuclear factor kappa B (RANKL) and then stimulated with LTB4-MS. Cytotoxicity, in vitro MS-LTB4 uptake, osteoclast formation and gene expression were measured. Results: We found that 5-LO negatively regulates osteoclastic formation in vivo during apical periodontitis development. In vitro, LTB4-MS were up-taken by macrophages and were not cytotoxic to the cells. LTB4-MS inhibited osteoclast formation and the synthesis of osteoclastogenic genes Acp5, Mmp9, Calcr and Ctsk. LTB4-MS inhibited differentiation of macrophages into an osteoclastic phenotype and cell activation under M-CSF and RANKL stimulus.

Resumo O objetivo deste trabalho foi Investigar a formação de osteoclastos in vivo e se o leucotrieno B4 (LTB4) incorporado em microesferas (MS) poderia ser usado como estratégia terapêutica para promover uma entrega sustentada do mediador e prevenir a diferenciação dos osteoclastos. Métodos: In vivo, a periodontite apical foi induzida em camundongos para investigar a diferenciação e sinalização de osteoclastos na ausência de 5-lipoxigenase (5-LO). In vitro, LTB4-MS foi preparado usando um processo de evaporação e extração de solvente de emulsão de óleo em água. A caracterização e a eficiência do encapsulamento do LTB4 foram investigadas. Macrófagos J774A.1 foram cultivados na presença de fator estimulador de colônia de monócitos (M-CSF) e ligante para o receptor ativador do fator nuclear kappa B (RANKL) e, então, estimulados com LTB4-MS. Citotoxicidade, captação in vitro de MS-LTB4, formação de osteoclastos e expressão gênica foram avaliadas. Resultados: A via 5-LO regula negativamente a formação de osteoclastos in vivo durante o desenvolvimento da periodontite apical. In vitro, LTB4-MS foram fagocitadas pelos macrófagos e não foram citotóxicos para as células. LTB4-MS inibiu a formação de osteoclastos e a síntese dos genes pró-osteoclastogênicos Acp5, Mmp9, Calcr e Ctsk. Conclusões: LTB4-MS inibiu a diferenciação de macrófagos em um fenótipo osteoclástico e a ativação celular sob estímulo de M-CSF e RANKL.

Enamel biomineralization under the effects of indomethacin and celecoxib non-steroidal anti-inflammatory drugs.

The aim of this study was to explore the effects of nonsteroidal anti-inflammatory drugs on biomineralization of enamel. Sixty C57Bl6 male mice were used, which were assigned into three groups: celecoxib (n = 20) or indomethacin (n = 20) treatment for a period of 28 days or received no medication (control group, n = 20). Visual inspection and microcomputed tomography were used to analyze enamel morphology. Scanning electron microscopy-Energy dispersive X-ray and Knoop microhardness test were used to quantify chemical element content (Ca, P, C, O) and enamel microhardness, respectively. Tissues were collected to investigate the synthesis, activity or nuclear translocation of metalloproteinase-20, transcription factor Runx2, dentin sialoprotein and cyclooxygenase-2 enzyme by means of immunohistochemistry, in situ zymography and indirect immunofluorescence. Treatment with indomethacin and celecoxib reduced the Ca and P content, microhardness and mineral density in enamel. Treatment with nonsteroidal anti-inflammatory drugs caused an accumulation of metalloproteinase-20 and overall increased enzymatic activity in enamel matrix, while the synthesis of the transcription factor Runx2 was inhibited by these drugs. Interestingly, indomethacin inhibited Runx2 translocation to the nucleus whereas celecoxib did not. Those findings show that non-steroidal anti-inflammatory drugs impact the enamel biomineralization and could be involved in the etiology tooth enamel defects if used during the period of tooth formation and mineralization.

Color stability and microhardness alteration of irradiated dental enamel treated with a high fluoride concentration toothpaste.

OBJECTIVES: Radiotherapy (RT) is a kind of head and neck cancer (HNC) treatment, which is associated to the habit of smoking and can develop collateral effects in the oral cavity, such as the increase of caries prevalence. This study evaluated the color alteration, the microhardness, and the remineralizing potential of high fluoride concentration toothpastes on irradiated teeth. MATERIALS AND METHODS: Forty bovine teeth were used (6 × 6 × 2 mm) and after color (EasyShade, VITA) and microhardness initial readings were separated into two groups: exposed to cigarette smoke and non-exposed. All samples were submitted to RT (30 Gy) and to cariogenic challenge. New color and microhardness readings were done. After RT (60 Gy), the samples were submitted to simulated toothbrushing (73,000 cycles = 5 years of brushing) with two different toothpastes: conventional (1450 ppm) and high fluoride concentration (5000 ppm). Final color and microhardness readings were done after brushing. Data were analyzed with 2-way ANOVA with repeated measures and Tukey's test (p < .05). RESULTS: There was no color difference after RT, nor after brushing (p > .05). However, after brushing, microhardness values increased for the samples treated with high fluoride concentration toothpaste (p < .05). CONCLUSION: Radiotherapy did not influence the teeth color, and the high fluoride concentration toothpaste presented remineralizing potential; therefore, it could be used on the caries prevention related to HNC radiation. CLINICAL RELEVANCE: Considering its remineralizing potential, toothpastes with high fluoride concentration could be a proper alternative for caries prevention in patients undergoing radiotherapy.

Preemptive analgesia with ibuprofen increases anesthetic efficacy in children with severe molar: a triple-blind randomized clinical trial.

Molar incisor hypomineralization (MIH) is often accompanied by dental hypersensitivity and difficulty in achieving effective analgesia. OBJECTIVE: This study evaluated the effectiveness of preemptive analgesia in children with severe MIH, post-eruptive enamel breakdown, and hypersensitivity. METHODOLOGY: Ibuprofen (10 mg/kg child weight) or placebo was administered, followed by infiltrative anesthesia and restoration with resin composite. Hypersensitivity was evaluated in five moments. The data were analyzed using the chi-square test, Fisher's exact test, and t-test. RESULTS: Preemptive analgesia provided benefits for the treatment of severe cases of MIH, with an increase in the effectiveness of infiltrative anesthesia and improved patient comfort during the restorative procedure. CONCLUSION: Preemptive analgesia has shown efficacy in reducing hypersensitivity during restorative dental procedures, evidencing the significance of this study for patients with MIH and hypersensitivity.

Knowledge, attitudes, and psychosocial impacts among Brazilian Pediatric Dentists during COVID-19 pandemic.

In this study, we evaluated the knowledge, attitudes, and psychosocial impacts among Brazilian pediatric dentists during the COVID-19 pandemic. A cross-sectional study with primary data collection was carried out using an online structured questionnaire. Data were submitted to descriptive analysis by using absolute and relative frequencies. A chi-square test was used for association analysis and log-linear regression models to estimate the prevalence ratio (5%). The population comprised mostly women and knowledge regarding COVID-19 was satisfactory (above 80% in most items). N95 masks and faceshields were used, albeit 64.22% reported difficulty in providing dental care to children due to the need for extra Personal Protective Equipment. Thirty eight percent provided urgency/emergency dental care, 59.78% performed invasive procedures, 59.56% used high speed handpieces, 8.44% started using cariostatics, and 6.22% introduced the use of chemomechanical caries removal agents. Fear for the future (PR = 1.21) and use of medications (for anxiety, depression, or insomnia) increased (PR = 1.16) among the ones who had wage losses. Brazilian pediatric dentists have knowledge about COVID-19, and attitudes in their clinical routines changed due the pandemic. Financial life was harmed and a negative impact of the pandemic in psychosocial aspects of workers was found.

Preemptive analgesia with ibuprofen increases anesthetic efficacy in children with severe molar hypomineralization: a triple-blind randomized clinical trial

Abstract Molar incisor hypomineralization (MIH) is often accompanied by dental hypersensitivity and difficulty in achieving effective analgesia. Objective: This study evaluated the effectiveness of preemptive analgesia in children with severe MIH, post-eruptive enamel breakdown, and hypersensitivity. Methodology: Ibuprofen (10 mg/kg child weight) or placebo was administered, followed by infiltrative anesthesia and restoration with resin composite. Hypersensitivity was evaluated in five moments. The data were analyzed using the chi-square test, Fisher's exact test, and t-test. Results: Preemptive analgesia provided benefits for the treatment of severe cases of MIH, with an increase in the effectiveness of infiltrative anesthesia and improved patient comfort during the restorative procedure. Conclusion: Preemptive analgesia has shown efficacy in reducing hypersensitivity during restorative dental procedures, evidencing the significance of this study for patients with MIH and hypersensitivity.

Visual Inspection and Toothbrush Care: A Mother-Baby Paired Cross-Sectional Study

ABSTRACT Objective To evaluate the physical conditions and presence of residues of toothbrushes used by mothers and their babies and mothers' knowledge about toothbrush care. Material and Methods This was a cross-sectional study comprising a convenience sample represented by 60 mother-baby pairs. The mothers answered a questionnaire to evaluate their knowledge of toothbrush care. A calibrated dentist performed a visual inspection of the toothbrushes. Statistical analysis was performed using the chi-square and Fisher's exact tests, with a significance level of 5%. Results It was found that 82% of the mothers had never received instructions regarding the care of toothbrushes after use (p=0.024). Most of them believed that their toothbrushes (70%) and their children's toothbrushes (88%) were in good condition to use (p=0.043). However, most mother's toothbrushes presented an unacceptable deformity of the bristles (65%) and the presence of residues (60%). In addition, babies' toothbrushes also presented unacceptable deformities of the bristles (52%) and residues (55%). There was an association between the lack of instructions received by the mother and the presence of deformity and residues on the mother's toothbrush bristles (p=0.037 and p=0.003, respectively). Conclusion Most mothers had never received instructions regarding toothbrush care, which is reflected in the condition of their and their baby's toothbrushes, which presented unacceptable physical conditions concerning deformation and presence of residues.