Impact of Non-Surgical Periodontal Treatment on the Concentration and Level of MRP-8/14 (Calprotectin) as an Inflammatory Biomarker in Women with Periodontitis and Rheumatoid Arthritis: A Quasi-Experimental Study.

The aim of this study was to evaluate the impact of non-surgical periodontal treatment (NS-PT) on periodontal parameters and inflammatory biomarkers in the concentration and level of calprotectin (CLP) in women with periodontitis and rheumatoid arthritis (RA). In this quasi-experimental study, we evaluated 30 women (mean age: 52.0 ± 5.8 years) with periodontitis and RA who had been diagnosed and treated for RA for more than 3 years and whose activity markers remained at similar values without significant reduction over three consecutive months. Patients underwent NS-PT, which included plaque control, scaling, and root planing. Serum and saliva samples, periodontal indices, RA activity markers, Disease Activity Score-28 (DAS28), the erythrocyte sedimentation rate (ESR), and the C-reactive protein (CRP) and CLP contents were measured at the beginning of the study and 6 and 12 weeks after NS-PT. Parametric and nonparametric tests were used in the analysis. The mean age was 52.0 ± 5.8 years. Compared to the baseline results, all periodontal indices were significantly reduced 6 and 12 weeks after NS-PT (p < 0.001). DAS28 was also significantly reduced after 12 weeks (p < 0.0001). Similarly, the serum CLP concentration decreased 6 and 12 weeks after NS-PT (p < 0.0001). Of the patients, 100% presented lower levels of CRP and ESR (p < 0.0001). Overall, NS-PT reduced inflammation and disease activity, highlighting the importance of oral health in the control and treatment of systemic diseases such as RA and confirming that NS-PT effectively reduces periodontitis activity and plays a key role in modulating RA activity. Therefore, NS-PT should be considered as an adjunct treatment for RA.

The Distribution of Eight Antimicrobial Resistance Genes in Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii Strains Isolated from Dental Plaque as Oral Commensals.

It has been proposed that oral commensal bacteria are potential reservoirs of a wide variety of antimicrobial resistance genes (ARGs) and could be the source of pathogenic bacteria; however, there is scarce information regarding this. In this study, three common streptococci of the mitis group (S. oralis, S. sanguinis, and S. gordonii) isolated from dental plaque (DP) were screened to identify if they were frequent reservoirs of specific ARGs (blaTEM, cfxA, tetM, tetW, tetQ, ermA, ermB, and ermC). DP samples were collected from 80 adults; one part of the sample was cultured, and from the other part DNA was obtained for first screening of the three streptococci species and the ARGs of interest. Selected samples were plated and colonies were selected for molecular identification. Thirty identified species were screened for the presence of the ARGs. From those selected, all of the S. sanguinis and S. oralis carried at least three, while only 30% of S. gordonii strains carried three or more. The most prevalent were tetM in 73%, and blaTEM and tetW both in 66.6%. On the other hand, ermA and cfxA were not present. Oral streptococci from the mitis group could be considered frequent reservoirs of specifically tetM, blaTEM, and tetW. In contrast, these three species appear not to be reservoirs of ermA and cfxA.

Use or abuse of antibiotics as prophylactic therapy in oral surgery: A systematic review.

BACKGROUD: Antibiotics are a type of medication routinely prescribed by dental professionals; however, it is very common that the administration is not justified. Around 15% of dentists admit that they have administered antibiotics unnecessarily more than once a week. The objective of this project is to identify the effectiveness of the use of antibiotics as prophylactic therapy in oral surgery, and to carry out an analysis of the alternatives to pharmacological therapy. METHODS: The search strategy was carried out in the PubMed, Scopus, and ScienceDirect databases. For study selection, a first filter was carried out by title and abstract, which mentioned the use of prophylactic antibiotics in some type of oral surgery. To establish the risk of bias, the JBI Critical Appraisal Checklist for Randomized Controlled Trials was utilized. RESULTS: The type of antibiotics most prescribed as prophylactic therapy were beta-lactams, which were indicated in 100% of the studies. Penicillins predominated, observing amoxicillin as the most indicated drug in 54.1% of the studies (n = 13) followed by the use of amoxicillin in conjunction with clavulanic acid in 33.3% of the studies (n = 8). Of the 21 studies included, 17 mention that there is insufficient evidence to support the use of antibiotics as prophylactic therapy in patients who will undergo some type of oral surgery. CONCLUSIONS: Without a doubt, the biggest challenge is to develop academic update strategies aimed at dentists with active clinical practice and dental students from educational and government institutions to provide updated information about the correct use of prescription drugs.

[Polymorphisms associated with dental caries in pediatric populations: a systematic review]. / Polimorfismos asociados a la caries dental en poblaciones pediátricas: una revisión sistemática.

Single nucleotide polymorphisms (SNPs) have been reported to play an important role in the etiology of dental caries. The aim of this research was, through a systematic review, to identify SNPs recently associated with dental caries in pediatric populations. We included studies performed in humans up to 18 years of age that evaluated the relationship between SNPs and dental caries from 2017 to 2022. Articles that covered other study variables were excluded. PubMed, ScienceDirect and Web of Science were used to search for information and the included articles were evaluated with one of the Joanna Briggs Institute's tools. Twenty-five articles were selected, 60% of which were given high methodological quality. A total of 10,743 research subjects, ranging in age from 20 months to 17 years, participated in the study. The SNPs considered risk factors were identified in the genes miRNA202, VDR, AMELX, TUFT1, KLK4, MBL2, ENAM, DEFB1, HLA-DRB1, TAS1R1, DSPP, RUNX2 and MMP13; those considered protective factors were identified in the genes MMP20, AMBN, MMP9, TIMP2, TNF-α, VDR, IL1B, ENAM and HLA-DRB1. This systematic review presents the genetic polymorphisms that are associated with the etiology of caries in children and adolescents, some of which act as risk factors and others as protective factors against the disease.

Se ha reportado que los polimorfismos de nucleótido único (SNPs) juegan un papel importante en la etiología de la caries dental. El objetivo de esta investigación fue, a través de una revisión sistemática, identificar los SNPs asociados recientemente a la caries dental en poblaciones pediátricas. Se incluyeron estudios realizados en humanos de hasta 18 años de edad que evaluaron la relación entre los SNPs y la caries dental, publicados desde el 2017 hasta el 2022. Se excluyeron los artículos que abarcaron otras variables de estudio. PubMed, ScienceDirect y Web of Science se utilizaron para la búsqueda de información y los artículos incluidos fueron evaluados con una de las herramientas del Instituto Joanna Briggs. Fueron seleccionados 25 artículos, al 60% de ellos se le otorgó calidad metodológica alta. En total participaron 10,743 sujetos de invetigación, cuyas edades variaron de 20 meses a 17 años. Los SNPs considerados factores de riesgo fueron identificados en los genes miRNA202, VDR, AMELX, TUFT1, KLK4, MBL2, ENAM, DEFB1, HLA-DRB1, TAS1R1, DSPP, RUNX2 y MMP13, los considerados factores de protección se identificaron en los genes MMP20, AMBN, MMP9, TIMP2, TNF-α, VDR, IL1B, ENAM y HLA-DRB1. Esta revisión sistemática expone los polimorfismos genéticos que se encuentran asociados a la etiología de la caries en niños y adolescentes, algunos de los cuales actúan como factores de riesgo y otros como factores de protección ante la enfermedad.

Bactericidal Activity of Silver Nanoparticles on Oral Biofilms Related to Patients with and without Periodontal Disease.

BACKGROUND AND OBJECTIVES: Periodontal disease (PD) is a multifactorial oral disease regularly caused by bacterial biofilms. Silver nanoparticles (AgNP) have offered good antimicrobial activity; moreover, there is no available scientific information related to their antimicrobial effects in biofilms from patients with PD. This study reports the bactericidal activity of AgNP against oral biofilms related to PD. MATERIALS AND METHODS: AgNP of two average particle sizes were prepared and characterized. Sixty biofilms were collected from patients with (30 subjects) and without PD (30 subjects). Minimal inhibitory concentrations of AgNP were calculated and the distribution of bacterial species was defined by polymerase chain reaction. RESULTS: Well-dispersed sizes of AgNP were obtained (5.4 ± 1.3 and 17.5 ± 3.4 nm) with an adequate electrical stability (-38.2 ± 5.8 and -32.6 ± 5.4 mV, respectively). AgNP showed antimicrobial activities for all oral samples; however, the smaller AgNP had significantly the most increased bactericidal effects (71.7 ± 39.1 µg/mL). The most resistant bacteria were found in biofilms from PD subjects (p < 0.05). P. gingivalis, T. denticola, and T. forsythia were present in all PD biofilms (100%). CONCLUSIONS: The AgNP showed efficient bactericidal properties as an alternative therapy for the control or progression of PD.

Evaluación antifúngica del ozono contra Candida albicans: estudio in vitro / Antifungal evaluation of ozone against Candida albicans: in vitro study

Introducción: la Candida albicans (C. albicans) es un patógeno fúngico que puede causar infecciones superficiales o potencialmente mortales. Los biofilms de C. albicans muestran rasgos fenotípicos únicos, el más destacado es su notable resistencia a una amplia variedad de agentes antimicóticos. Una de las alternativas para inhibir el crecimiento de este microorganismo es el ozono debido a sus propiedades bactericidas, fungicidas y virucidas; sin embargo, escasa información ha sido reportada en C. albicans. Objetivo: el objetivo de este estudio fue evaluar el efecto fungicida del ozono en C. albicans. Material y métodos: la metodología consistió en agregar ozono a tubos de ensayo con medios de caldo nutritivo en diversas concentraciones y tiempos de ozonización. El efecto fungicida fue determinado con la determinación del número de colonias de C. albicans en agar nutritivo a través de procedimiento microbiológicos estandarizados por triplicado. Resultados: todas las muestras con ozono mostraron adecuados niveles de inhibición de crecimiento del microorganismo. Además, el efecto fungicida del ozono se encontró para ser significativamente dependiente del tiempo de ozonización y de la concentración. Conclusión: el uso de terapia con ozono podría tener potencial en el control de infecciones micóticas causadas por la presencia de C. albicans (AU)

Introduction: Candida albicans (C. albicans) is a fungal pathogen that can cause superficial or life-threatening infections. Biofilms of C. albicans display unique phenotypic traits, the most prominent being their remarkable resistance to a wide variety of antifungal agents. One of the alternatives to inhibit the growth of this microorganism is ozone due to its bactericidal, fungicidal and virucidal properties; however, little information has been reported on C. albicans. Objective: the objective of this study was to evaluate the fungicidal effect of ozone on C. albicans. Material and methods: the methodology consisted in adding ozone to test tubes with nutrient broth media in various concentrations and ozonation times. The fungicidal effect was determined by determining the number of colonies of C. albicans in nutrient agar through standardized microbiological procedures in triplicate. Results: all the ozone samples showed adequate levels of growth inhibition of the microorganism. Furthermore, the fungicidal effect of ozone was found to be significantly dependent on ozonation time and concentration. Conclusion: the use of ozone therapy could have potential in the control of fungal infections caused by the presence of C. albicans (AU)

Root canal microbiota as an augmented reservoir of antimicrobial resistance genes in type 2 diabetes mellitus patients.

BACKGROUND: Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. METHODOLOGY: This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. RESULTS: tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. CONCLUSIONS: Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.

Antimicrobial resistance in odontogenic infections: A protocol for systematic review.

BACKGROUND: It is estimated that up to 90% of head and neck infections have an odontogenic origin, which are considered among the most common in the oral cavity and maxillofacial region. Bacterial resistance has been 1 of the main problems related to the treatment of this type of infection in recent years. The frequency of this resistance is increasing, which is mainly due to patient self-medication and the mutations that bacteria present. Therefore, the objective of this study is to analyze the antimicrobial resistance of antibiotics commonly administered for the treatment of odontogenic infections. METHOD: To carry out the study, PubMed, ScienceDirect, and Scopus databases were reviewed using the keywords "odontogenic infection", "pharmacological treatment", and "microbial resistance. Studies whose main objective was the pharmacological treatment of odontogenic infections were selected. Exclusions were review-type studies, systematic reviews, or in vitro or animal model studies. For the analysis of risk of bias, the Checklist for Analytical Cross-Sectional Studies of the Joanna Briggs Institute was used. The search and analysis of the studies was carried out by 2 researchers independently. RESULTS: A total of 13 studies were included in this review. The mean age was 39.6 years; the location of the infection in the study subjects was in the submandibular and vestibular spaces; there were periodontal, periapical, and dentoalveolar lesions; the main microorganisms identified were Streptococcus, Staphylococcus, Prevotella, Peptostreptococcus, Clostridium, and Klebsiella; and finally, the main microorganisms identified for bacterial resistance were penicillin, clindamycin and amoxicillin. CONCLUSION: The health professional is obliged to update their knowledge to avoid such antibiotic resistance and thus provide better patient care.

Tumor invasion front in oral squamous cell carcinoma.

Oral squamous cell carcinoma is a neoplasm that originates from the epithelial mucosa. It is usually more frequent between the fifth and sixth decades of life, and more than 90% of carcinomas of the oral cavity are squamous cell carcinoma. It is an invasive neoplasia with a significant recurrence rate; 40% of patients present with metastases in the cervical lymph nodes at the time of diagnosis. The tumor invasion front is a characteristic of tumor growth, which can be infiltrative or noninvasive. The histopathological parameters examined include the number of mitoses, depth of the tumor, invasion pattern, degree of keratinization, and nuclear pleomorphism. For the pathologist, these parameters are routinely evaluated but are not reported to the treating physician in all cases, which we consider to be useful information when determining the therapeutic route.

Nanopartículas de plata contra bacterias presentes en biofilm dental de pacientes pediátricos / Silver nanoparticles against bacteria present in dental biofilm of pediatric patients

Introducción: el biofilm dental microbiano es el precursor de diversas enfermedades orales, una de ellas la caries, ésta representa la enferme- dad oral más significativa a nivel mundial, con una incidencia de 1.76 billones de niños afectados. Las nanopartículas de plata (AgNPs) se están usando como alternativa para el control y prevención del biofilm dental, ya que poseen propiedades antimicrobianas contra bacterias relacionadas a estas enfermedades. Sin embargo, no hay estudios que evalúen este comportamiento en pacientes pediátricos. Objetivo: eva- luar la actividad antimicrobiana de las AgNPs en bacterias de aislados clínicos tomados de pacientes pediátricos. Material y métodos: se tomó muestra del biofilm dental de 22 pacientes pediátricos, el efecto micro- biológico se evaluó mediante ensayos microbiológicos estandarizados internacionalmente por triplicado, usando dos diferentes tamaños de AgNPs. Resultados: los dos tamaños de AgNPs mostraron inhibición bacteriana, sin embargo, sólo se vio una diferencia estadísticamente significativa entre el género (p < 0.05), además, en general, hubo una correlación positiva significativa en relación a la concentración de las AgNPs y la velocidad del crecimiento bacteriano (p < 0.05). Conclusión: las AgNPs se pueden considerar como una alternativa para la prevención del biofilm dental y de esta manera para el control de diferentes enfermedades orales (AU))

Introduction: dental biofilm is the precursor of oral diseases, one of them dental caries, this represents the most significant oral disease worldwide with an incidence of 1.76 billion affected children. Silver nanoparticles (AgNPs) are being used as an alternative for the control and prevention of dental biofilm since they have antimicrobial properties against bacteria related to these diseases. However, there are no studies evaluating this behavior in pediatric patients. Objective: to evaluate the antimicrobial activity of AgNPs in bacteria from clinical isolates taken from pediatric patients. Material and methods: a sample of dental biofilm was taken from 22 pediatric patients, the microbiological effect was evaluated by international standardized microbiological tests in triplicate, using two different sizes of AgNPs. Results: the two sizes of AgNPs showed bacterial inhibition, however, only a statistically significant difference was seen between gender (p < 0.05), in addition, in general, there was a significant positive correlation in relation to the concentration of AgNPs and the speed bacterial growth (p < 0.05). Conclusion: AgNPs can be considered as an alternative for the prevention of dental biofilm and thus for the control of different oral diseases (AU)

Anti-Adherence and Antimicrobial Activities of Silver Nanoparticles against Serotypes C and K of Streptococcus mutans on Orthodontic Appliances.

Background and Objectives: Streptococcus mutans (S. mutans) is the main microorganism associated with the presence of dental caries and specific serotypes of this bacteria have been related to several systemic diseases limiting general health. In orthodontics, white spot lesions (WSL), represent a great challenge for clinicians due to the great fluctuation of their prevalence and incidence during conventional orthodontic treatments. Although silver nanoparticles (AgNP) have been demonstrated to have great antimicrobial properties in several microorganisms, including S. mutans bacteria, there is no available information about anti adherence and antimicrobial properties of AgNP exposed to two of the most relevant serotypes of S. mutans adhered on orthodontic materials used for conventional therapeutics. The objective of this study was to determine anti-adherence and antimicrobial levels of AgNP against serotypes c and k of S. mutans on conventional orthodontic appliances. Materials and Methods: An AgNP solution was prepared and characterized using dispersion light scattering (DLS) and transmission electron microscopy (TEM). Antimicrobial and anti-adherence activities of AgNP were determined using minimal inhibitory concentrations (MIC) and bacterial adherence testing against serotypes c and k of S. mutans clinically isolated and confirmed by PCR assay. Results: The prepared AgNP had spherical shapes with a good size distribution (29.3 ± 0.7 nm) with negative and well-defined electrical charges (−36.5 ± 5.7 mV). AgNP had good bacterial growth (55.7 ± 19.3 µg/mL for serotype c, and 111.4 ± 38.6 µg/mL for serotype k) and adherence inhibitions for all bacterial strains and orthodontic wires (p < 0.05). The serotype k showed statistically the highest microbial adherence (p < 0.05). The SS wires promoted more bacterial adhesion (149.0 ± 253.6 UFC/mL × 104) than CuNiTi (3.3 ± 6.0 UFC/mL × 104) and NiTi (101.1 ± 108.5 UFC/mL × 104) arches. SEM analysis suggests CuNiTi wires demonstrated better topographical conditions for bacterial adherence while AFM evaluation determined cell wall irregularities in bacterial cells exposed to AgNP. Conclusions: This study suggests the widespread use of AgNP as a potential anti-adherent and antimicrobial agent for the prevention of WSL during conventional orthodontic therapies and, collaterally, other systemic diseases.

Poly-ε-Caprolactone-Hydroxyapatite-Alumina (PCL-HA-α-Al2O3) Electrospun Nanofibers in Wistar Rats.

Biodegradable polymers of natural origin are ideal for the development of processes in tissue engineering due to their immunogenic potential and ability to interact with living tissues. However, some synthetic polymers have been developed in recent years for use in tissue engineering, such as Poly-ε-caprolactone. The nanotechnology and the electrospinning process are perceived to produce biomaterials in the form of nanofibers with diverse unique properties. Biocompatibility tests of poly-ε-caprolactone nanofibers embedded with hydroxyapatite and alumina nanoparticles manufactured by means of the electrospinning technique were carried out in Wistar rats to be used as oral dressings. Hydroxyapatite as a material is used because of its great compatibility, bioactivity, and osteoconductive properties. The PCL, PCL-HA, PCL-α-Al2O3, and PCL-HA-α-Al2O3 nanofibers obtained in the process were characterized by infrared spectroscopy and scanning electron microscopy. The nanofibers had an average diameter of (840 ± 230) nm. The nanofiber implants were placed and tested at 2, 4, and 6 weeks in the subcutaneous tissue of the rats to give a chronic inflammatory infiltrate, characteristic foreign body reaction, which decreased slightly at 6 weeks with the addition of hydroxyapatite and alumina ceramic particles. The biocompatibility test showed a foreign body reaction that produces a layer of collagen and fibroblasts. Tissue loss and necrosis were not observed due to the coating of the material, but a slight decrease in the inflammatory infiltrate occurred in the last evaluation period, which is indicative of the beginning of the acceptance of the tested materials by the organism.

Root canal microbiota as an augmented reservoir of antimicrobial resistance genes in type 2 diabetes mellitus patients

Abstract Antimicrobial resistance is a global public health problem. Root canal microbiota associated with apical periodontitis represents a well-known reservoir of antimicrobial resistance genes (ARGs). However, the effect of type 2 diabetes mellitus (T2DM) in this reservoir is unknown. This study aimed to establish if root canal microbiota associated with apical periodontitis in T2DM patients is an augmented reservoir by identifying the prevalence of nine common ARGs and comparing it with the prevalence in nondiabetic patients. Methodology This cross-sectional study included two groups: A T2DM group conformed of 20 patients with at least ten years of living with T2DM and a control group of 30 nondiabetic participants. Premolar or molar teeth with pulp necrosis and apical periodontitis were included. A sample was collected from each root canal before endodontic treatment. DNA was extracted, and ARGs were identified by polymerase chain reaction. Results tetW and tetM genes were the most frequent (93.3 and 91.6%, respectively), while ermA was the least frequent (8.3%) in the total population. The distribution of the ARGs was similar in both groups, but a significant difference (p<0.005) was present in ermB, ermC, cfxA, and tetQ genes, being more frequent in the T2DM group. A total of eighty percent of the T2DM patients presented a minimum of four ARGs, while 76.6% of the control group presented a maximum of three. Conclusions Root canal microbiota associated with apical periodontitis in T2DM patients carries more ARGs. Therefore, this pathological niche could be considered an augmented reservoir.

COVID-19 and its manifestations in the oral cavity: A systematic review.

BACKGROUND: SARS-CoV-2 is the virus responsible for coronavirus disease-19 (COVID-19) disease, which has been shown to trigger multiple affectations. One of the first tissue areas to come into contact with the virus is the oral cavity, which develops various alterations. Hence, the objective of this systematic review was to identify the main signs and symptoms of this disease in the oral cavity, and the following research question was established: What are the main oral signs and symptoms in COVID-19-positive persons? METHODS: The electronic databases of PUBMED, SCOPUS, and SCIENCE DIRECT were analyzed, the keywords "ORAL DISEASES," "ORAL MANIFESTACTIONS," and "COVID-19" were used taking into account the following inclusion criteria: studies whose main objective was oral manifestations secondary to the confirmation of COVID-19, plus clinical cases, case series, and retrospective or prospective studies. For the assessment of the risk of bias the JBI Critical Appraisal Checklist for Case Series tool was used. RESULTS: A total of 18 studies were included, the most common initial signs/symptoms after contagion of SARS-CoV-2 were dysgeusia, dry mouth, and burning mouth, and the main signs/symptoms were the presence of ulcerative lesions, dysgeusia, and Candida albicans infections. CONCLUSIONS: It is very important to detect any alteration in the mucosa in patients with COVID-19 and to provide assertive treatment to avoid complications, and try to maintain adequate oral hygiene throughout the course of the disease to avoid the colonization of opportunistic microorganisms and to avoid complications both orally and systemically.

Effect of Streptococcus mutans on surface-topography, microhardness, and mechanical properties of contemporary resin composites.

OBJECTIVE: Dental caries is the most prevalent disease globally, and Streptococcus mutans (S. mutans) is a common associated oral bacteria. Additionally, S. mutans possess esterase activity capable of degrading resin composites (RC). However, the effect of degradation on the physical-mechanical properties of the RC has not been extensively studied. We evaluated the flexure strength (FS), the diametral tensile strength (DTS), the modulus of elasticity (ME), and the microhardness of three contemporary RC to establish if S. mutans could affect them. METHODS: One hundred thirty-eight bar-shaped and 276 disc-shaped specimens were fabricated with Enamel Plus HRi, IPS Empress Direct, and Clearfil AP-X, and physical-mechanical testing was done after been incubated during 30 and 60 days in culture media with or without S. mutans. Also, a scanning electron microscope was used to identify surface changes. RESULTS: None of the tested RC were affected in their mechanical properties (FS, ME, and DTS). However, Clearfil AP-X and Enamel Plus HRI showed eroded surfaces and a decreased microhardness after 30 and 60 days S. mutans incubation. IPS Empress Direct presented the lowest values in all the tests, but its physical-mechanical features and surface were not affected by bacteria's exposure. CONCLUSIONS: Exposure to S. mutans could affect some contemporary RC; however, the effect seems superficial since its mechanical features were not affected.

Evaluación de lesiones orales en pacientes intubados y su asociación con el motivo de hospitalización / Evaluation of oral lesions in intubated patients and its association with the reason of hospitalization

asistencia ventilatoria cuando la vía aérea y la consciencia están comprometidas. Los elementos utilizados en este procedimiento se encuentran en contacto directo con estructuras dentofaciales, causando diversos tipos de lesiones, principalmente bucales. Aunque existen cuidados clínicos durante procesos de intubación, hay poca información, particularmente de la zona norte del país donde se hayan evaluado las posibles asociaciones entre los motivos de consulta más frecuentes y las diversas características, tanto clínicas como no clínicas de pacientes que han sido intubados. Objetivo: Identificar las alteraciones bucodentales más frecuentes en pacientes intubados, así como explorar las posibles asociaciones de acuerdo con los motivos de intubación más frecuentes. Material y métodos: Se realizó un estudio observacional, transversal y comparativo en el cual se evaluaron alteraciones bucodentales y sistémicas de pacientes intubados. Los grupos de estudio se desarrollaron de acuerdo con el motivo de intubación y la determinación de las asociaciones fue con cada una de las alteraciones bucodentales y sistémicas. Resultados: El motivo de intubación más frecuente fue el evento cerebral vascular (EVC) y las alteraciones dentofaciales más prevalentes fueron caries, lengua saburral y cálculo dental, entre otras. Además, se encontraron diferencias significativas entre pacientes con EVC, mostrando una mayor frecuencia en tabaquismo, hipertensión arterial y diabetes mellitus, así como en la presencia de gingivitis y úlceras. Pacientes con traumatismo craneoencefálico (TCE) tuvieron mayor frecuencia en la presencia de periodontitis. Conclusión: El motivo de hospitalización y las condiciones sistémicas preexistentes pueden ser un factor de riesgo para desarrollar lesiones bucales específicas antes y durante el periodo de intubación (AU)

Introduction: Intubation is a procedure that allows ventilatory assistance when the airway and consciousness are compromised. The elements used in this procedure are in direct contact with dentofacial structures causing various types of injuries, mainly oral. Although there is clinical care during intubation processes, there is little information, particularly from the northern part of the country where the possible associations between the most frequent reasons for consultation and the various clinical and non-clinical characteristics of patients who have been intubated have been evaluated. Objective: The objectives of the present study were to identify the most frequent oral alterations in intubated patients, as well as to explore possible associations according to the most frequent reasons for intubation. Material and methods: An observational, cross-sectional and comparative study was carried out in which oral and systemic alterations of intubated patients were evaluated. The study groups were formed according to the reason for intubation and the association was determined with each of the oral and systemic disorders. Results: The most frequent reason for intubation was the vascular cerebral event (CVA) and the most prevalent dentofacial alterations were caries, coated tongue, and dental calculus, among others. In addition, significant differences were found between patients with CVA, showing a higher frequency in smoking, hypertension, and diabetes mellitus, as well as in the presence of gingivitis and ulcers. Patients with traumatic brain injury (TBI) had a higher frequency in the presence of periodontitis. Conclusion: The reason for hospitalization and pre-existing systemic conditions can be a risk factor for developing specific oral lesions before and during the intubation period (AU)

Stem Cells as a Model of Study of SARS-CoV-2 and COVID-19: A Systematic Review of the Literature.

BACKGROUND: The SARS-CoV-2 virus is the cause of the latest pandemic of the 21st century; it is responsible for the development of COVID-19. Within the multiple study models for both the biology and the treatment of SARS-CoV-2, the use of stem cells has been proposed because of their ability to increase the immune response and to repair tissue. Therefore, the objective of this review is to evaluate the role of stem cells against SARS-CoV-2 and COVID-19 in order to identify their potential as a study model and as a possible therapeutic source against tissue damage caused by this virus. Therefore, the following research question was established: What is the role of stem cells in the study of SARS-CoV-2 and the treatment of COVID-19? MATERIALS AND METHODS: A search was carried out in the electronic databases of PUBMED, Scopus, and ScienceDirect. The following keywords were used: "SARS-CoV-2," "COVID-19," and "STEM CELL," plus independent search strategies with the Boolean operators "OR" and "AND." The identified reports were those whose main objective was the study of stem cells in relation to SARS-CoV-2 or COVID-19. For the development of this study, the following inclusion criteria were taken into account: studies whose main objective was the study of stem cells in relation to SARS-CoV-2 or COVID-19 and clinical case studies, case reports, clinical trials, pilot studies, in vitro, or in vivo studies. For assessment of the risk of bias for in vitro studies, the SciRAP tool was used. The data collected for each type of study, clinical or in vitro, were analyzed with descriptive statistics using the SPSS V.22 program. RESULTS: Of the total of studies included (n = 39), 22 corresponded to in vitro investigations and 17 to human studies (clinical cases (n = 9), case series (n = 2), pilot clinical trials (n = 5), clinical trials (n = 1)). In vitro studies that induced pluripotent stem cells were the most used (n = 12), and in clinical studies, the umbilical stem cells derived were the most reported (n = 11). The mean age of the study subjects was 58.3 years. After the application of stem cell therapy, the follow-up period was 8 days minimum and 90 days maximum. Discussion. The mechanism by which the virus enters the cell is through protein "S," located on the surface of the membrane, by recognizing the ACE2 receptor located on the target cell. The evidence that the expression of ACE2 and TMPRSS2 in stem cells indicates that stem cells from bone marrow and amniotic fluid have very little expression. This shows that stem cell has a low risk of infection with SARS-CoV-2. CONCLUSION: The use of stem cells is a highly relevant therapeutic option. It has been shown in both in vitro studies and clinical trials that it counteracts the excessive secretion of cytokines. There are even more studies that focus on long-term follow-up; thus, the potential for major side effects can be analyzed more clearly. Finally, the ethical use of stem cells from fetal or infant origin needs to be regulated. The study was registered in PROSPERO (no. CRD42021229038). The limitations of the study were because of the methodology employed, the sample was not very large, and the follow-up period of the clinical studies was relatively short.

Preliminary Biocompatibility Tests of Poly-ε-Caprolactone/Silver Nanofibers in Wistar Rats.

Currently, nanotechnology is perceived as a promising science that produces materials with diverse unique properties at a nanometric scale. Biocompatibility tests of poly-ε-caprolactone nanofibers, embedded with silver nanoparticles manufactured by means of the electrospinning technique, were carried out in Wistar rats to be used as oral dressings for the eradication of bacteria. Solutions of 12.5, 25, 50 and 100 mM of silver nitrate were made using N-dimethylformamide (DMF) and tetrahydrofuran (THF) as reducing solvents with 8% of poly-ε-caprolactone (PCL) polymer. The solutions were electrospun, and the nanofibers obtained in the process were characterized by infrared spectroscopy, Raman spectroscopy, dark field optical microscopy, scanning electron microscopy and X-ray scattering spectroscopy. The nanofibers had an average diameter of 400 ± 100 nm. Once the characterization of the material was done, three implants of each concentration of the nanofibers were formed and placed in the subcutaneous tissue of the rats. Three experimental subjects were used, leaving the material in them for a length of two, four and six weeks, respectively. The rats showed good healing, with the lesions completely healed at four weeks after implantation. After that time, biopsies were taken, and histopathological sections were made to evaluate the inflammatory infiltrate. The tissues of the rats presented chronic inflammatory infiltrate composed mainly of lymphocytes and giant multinucleated cells. The material was rejected by the rats when a layer of collagen and fibroblasts was produced, coating the material, a process characteristic of a foreign body reaction.

Expression of MicroRNAs in Periodontal Disease: A Systematic Review.

INTRODUCTION: Periodontal disease (PD) is a chronic inflammation of the soft tissues that support the structure of the tooth, and miRNAs are highly dynamic molecules that participate in the regulation of gene expression interfering with multiple genetic targets. The dysregulation of the expression of miRNAs has been associated with different types of pathologies; therefore, they are excellent molecules to be studied as biomarkers. Material and Methods. A search was made in the electronic databases of PubMed, Scopus, and Science Direct. The following key words were used: "microRNAs," "miRNAs," "periodontal disease," "periodontitis," and "biomarker"; employee independent search strategies with the Boolean operators "OR" and "AND"; a further search of the references of the selected studies was performed to detect potential studies that met the selection criteria. The data recollected from each article were author, country, year of publication, sample size, type of sample used to identify miRNAs, methodology used to identify miRNAs, type of periodontal disease, and miRNAs identified. RESULTS: Of the 13 selected studies, 6 used gingival tissue as a sample for the identification of miRNAs, 3 used gingival fluid, 2 used saliva, 1 used serum, and another used periodontal tissue. Chronic periodontitis was the most studied periodontal disease in 9 of the 13 selected articles; 7 used microarrays as the main technique for the identification of miRNAs. qRT-PCR was the assay choice to validate the identified miRNAs. CONCLUSION: The main type of periodontal disease on which most studies are focused is chronic periodontitis, with the main miRNAs being hsa-miR-146a, hsa-miR-146b, hsa-miR-155, and hsa-miR-200. This systematic review is one of the first to carry out an analysis of the current role of miRNAs in PD as biomarkers.

Spindle cell carcinoma of the maxillary sinus with extension to the oral cavity.

Spindle cell carcinoma (SCC) is a rare variant of squamous cell carcinoma characterized by elongated and pleomorphic epithelial cells that resemble a sarcoma. Due to its rareness, and histological resemblance to various sarcomas, the diagnosis of this neoplasia is challenging. Herein we present the case of an 82-year-old female with a polypoid, ulcerated, soft tissue mass located on the left side of the maxilla. The tomographic examination showed a hyperdense mass that infiltrated the orbital cavity, ethmoidal cells, middle and lower nasal concha, maxillary sinus, zygomatic arch, and mandibular ramus on the left side. Histopathologically, the tumor was composed of spindle cells that were sarcomatous in appearance, with aberrant mitosis, along with a group of pleomorphic cells with a more epithelioid and hyperchromatic appearance on a stroma of densely vascularized fibrous tissue. The immunohistochemistry panel used to determine the lineage of the tumor rendered the diagnosis of SCC. The diagnosis of SCC is challenging to the pathologist since its morphology can resemble a sarcoma. Thus, immunohistochemistry is a valuable resource to support the diagnosis. We propose that SCC should be considered when examining a biphasic neoplasm with the aforementioned histological characteristics and markers.