RESUMO

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.

Assuntos

RESUMO

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.

Assuntos

RESUMO

OBJECTIVE: To compare direct visual analysis (DVA) and intraoral scanning (IOS) for the assessment of developmental defects of the enamel (DDE). METHODS: Thirty-nine extracted permanent human teeth with DDE were selected by an experienced examiner and digitised using IOS. The scanning was recorded using the OBS Studio software parallel to the IOS software to obtain a coloured high-definition MP4 file of the process. Two other experienced, blinded, and calibrated examiners randomly analysed the same teeth through DVA and IOS. A third examiner resolved any disagreements between the two examiners. Descriptive statistics were used to analyse the frequencies of the scores. Cohen's kappa test was used to determine whether the DVA scores were different from those assigned using IOS. Spearman's test was used to verify non-random examiner errors. The Chi-square test was used to compare score frequencies. Statistical significance was set at p <0.05. RESULTS: Scores indicating more severe and extended DDE (p <0.05) were more frequently assigned with IOS than with DVA (IOS: 25.64%, 25.64%, 38.46%, and 35.90% between one-third to two-third of the lingual, occlusal, mesial, and distal surfaces, respectively; vs. DVA: 10.26%, 7.69%, 15.38%, and 10.26% for the respective aforementioned tooth surfaces). Contrarily, 'no visible enamel defect' was significantly less assigned for IOS than for DVA (IOS: 15.38%, 43.59%, 35.90%, 15.38%, and 17.95% for buccal, lingual, occlusal, mesial, and distal surfaces, respectively; vs. DVA: 38.46%, 66.67%, 56.41%, 51.28%, and 43.59% for the respective aforementioned tooth surfaces). Kappa agreement ranged from fair to moderate when comparing DVA and IOS; the correlation between both methods was positive, indicating that the examiners assigned the scores properly and the differences arose from employing different methods. CONCLUSION: The assessment of DDE differed depending on the method used. IOS scores indicated more severe and extended DDE than DVA scores. Clinical investigation is the next step in validating the use of IOS for DDE diagnosis. CLINICAL SIGNIFICANCE: This study showed that DDE can be assessed differently using IOS. It is clinically relevant as it directly affects the determination of the severity of the defect and dental treatment planning.

Assuntos

RESUMO

The aim of this study was to evaluate the sensitivity, specificity, and predictive values of the fluorescence microscopy method in the detection of apical dental reabsorption after induction of apical periodontitis in animal models. Forty-first molars of mice, aged 6 to 8 weeks, had their root canals exposed to the oral environment or were maintained healthy as controls (n = 20). After 14 and 42 days, mice were euthanized and tissues were collected for histological evaluation by means of bright field and fluorescence microscopy. The accuracy of fluorescence microscopy in identifying apical external dental resorption was investigated using a diagnostic validation test based on the sensitivity (S) and specificity (E) properties. Bright-field microscopy revealed a higher number of specimens with scores of 1 to 3 - absence of apical dental resorption (n = 29; 52%), while fluorescence microscopy revealed a higher number of specimens with scores of 4 to 6 - presence of apical dental resorption (n = 37; 66%). Out of 56 specimens, 26 were TP, 11 were FP, and 19 were TN. No FN result was observed. Fluorescence microscopy presented a sensitivity value of 1, similar to the bright-field method, while specificity was lower (0.633). The accuracy of the fluorescent method to detect apical dental resorption was 0.804. Fluorescence microscopy revealed a higher number of false positive apical dental resorption than bright-field microscopy. The detection of apical dental resorption was not impacted by the sensitivity of the method but by its specificity.

Assuntos

RESUMO

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.

Assuntos

RESUMO

Purpose: The purpose of this case report is to describe a RUNX2 nonsense mutation associated with cleidocranial dysplasia (CCD) with unusual dental features. The patient was a 12-year-old Brazilian girl who sought dental care due to over-retention of primary teeth and absence of erupted permanent teeth. Clinical and radiographic examinations revealed multiple impacted permanent teeth, a prominent cingulum of the permanent impacted maxillary incisors and enamel defects (hypoplasia and hypomineralization) in addition to skeletal abnormalities. No supernumerary teeth were present. The diagnostic hypothesis of CCD was raised and the patient was refer- red to the genetic medical service, where the diagnosis was cofirmed. After RUNX2 genetic screening, including polymerase chain reaction and sequencing of both DNA strands, a heterozygous nonsense mutation was identified in exon 2 (c.193 C>T [Q65X]). This article reports unusual dental features in a patient with CCD.

Assuntos

RESUMO

Antibiotics misuse and overuse are concerning issues worldwide, especially in low middle-income countries. These practices contribute to the increasing rates of antimicrobial resistance. One efficient strategy to avoid them is antimicrobial stewardship programs. In this review, we focus on the possible approaches to spare the prescription of polymyxins and carbapenems for the treatment of Acinetobacter baumannii, carbapenem-resistant Enterobacterales, and Pseudomonas aeruginosas infections. Additionally, we highlight how to implement cumulative antibiograms and biomarkers to a sooner de-escalation of antibiotics.

RESUMO

Different types of brackets seem to influence the disruption of the oral microbial environment. Therefore, the aim of this study was to evaluate the influence of self-ligating brackets on the gingival crevicular fluid levels of the putative periodontal pathogens Aggregatibacter actinomycetemcomitans sorotype a (Aaa), Tannerella forsythia, Fusobacterium nucleatum, and Porphyromonas gingivalis. Sixty samples of crevicular fluid of twenty patients (11 boys and 9 girls) were analysed at baseline (T0) and after 30 (T1) and 60 (T2) days of bonding of the self-ligating (In-Ovation®R, Dentsply, GAC or SmartClip™, 3 M Unitek, Monrovia, CA, USA) and of one conventional bracket (Gemini™, 3 M Unitek, Monrovia, CA, USA) used with elastomeric ligatures. Total DNA from samples was extracted using CTAB-DNA precipitation method and Real-time PCR was performed to analyse bacterial level. Non-parametric Friedman and Wilcoxon tests were used for data analysis (p value of < 0.05). F. nucleatum presented a different level among the different brackets at T1 (p = 0.025), the highest level in the Gemini™ bracket when compared to the SmartClip™ bracket (p = 0.043). P. ginigvalis levels increased in the In-Ovation®R (p = 0.028) at T1. The subgingival levels of bacterial species associated with periodontal disease P. ginigvalis increased in the self-ligating brackets In-Ovation®R.Clinical Relevance: Some kinds of brackets could provide more retentive sites than others, and it seems to modulate the subgingival microbiota, since, in this study, we could observe the increase of the species associated with periodontal disease. Preventive protocols should be adopted in the use of self-ligating brackets.

Assuntos

RESUMO

BACKGROUND: Coexistence of cancer and COVID-19 is associated with worse outcomes. However, the studies on cancer-related characteristics associated with worse COVID-19 outcomes have shown controversial results. The objective of the study was to evaluate cancer-related characteristics associated with invasive mechanical ventilation use or in-hospital mortality in patients with COVID-19 admitted to intensive care unit (ICU). METHODS: We designed a cohort multicenter study including adults with active cancer admitted to ICU due to COVID-19. Seven cancer-related characteristics (cancer status, type of cancer, metastasis occurrence, recent chemotherapy, recent immunotherapy, lung tumor, and performance status) were introduced in a multilevel logistic regression model as first-level variables and hospital was introduced as second-level variable (random effect). Confounders were identified using directed acyclic graphs. RESULTS: We included 274 patients. Required to undergo invasive mechanical ventilation were 176 patients (64.2%) and none of the cancer-related characteristics were associated with mechanical ventilation use. Approximately 155 patients died in hospital (56.6%) and poor performance status, measured with the Eastern Cooperative Oncology Group (ECOG) score was associated with increased in-hospital mortality, with odds ratio = 3.54 (1.60-7.88, 95% CI) for ECOG =2 and odds ratio = 3.40 (1.60-7.22, 95% CI) for ECOG = 3 to 4. Cancer status, cancer type, metastatic tumor, lung cancer, and recent chemotherapy or immunotherapy were not associated with in-hospital mortality. CONCLUSIONS: In patients with active cancer and COVID-19 admitted to ICU, poor performance status was associated with in-hospital mortality but not with mechanical ventilation use. Cancer status, cancer type, metastatic tumor, lung cancer, and recent chemotherapy or immunotherapy were not associated with invasive mechanical ventilation use or in-hospital mortality.

RESUMO

Although the "seed and soil" hypothesis was proposed by Stephen Paget at the end of the 19th century, where he postulated that tumor cells (seeds) need a propitious medium (soil) to be able to establish metastases, only recently the tumor microenvironment started to be more studied in the field of Oncology. Multiple myeloma (MM), a malignancy of plasma cells, can be considered one of the types of cancers where there is more evidence in the literature of the central role that the bone marrow (BM) microenvironment plays, contributing to proliferation, survival, migration, and drug resistance of tumor cells. Despite all advances in the therapeutic arsenal for MM treatment in the last years, the disease remains incurable. Thus, studies aiming a better understanding of the pathophysiology of the disease, as well as searching for new therapeutic targets are necessary and welcome. Therefore, the present study aimed to evaluate the protein expression profiling of mononuclear cells derived from BM of MM patients in comparison with these same cell types derived from healthy individuals, in order to fill this gap in MM treatment. Proteomic analysis was performed using the mass spectrometry technique and further analyses were done using bioinformatics tools, to identify dysregulated biological pathways and/or processes in the BM microenvironment of patients with MM as a result of the disease. Among the pathways identified in this study, we can highlight an upregulation of proteins related to protein biosynthesis, especially chaperone proteins, in patients with MM. Additionally, we also found an upregulation of several proteins involved in energy metabolism, which is one of the cancer hallmarks. Finally, with regard to the downregulated proteins, we can highlight mainly those involved in different pathways of the immune response, corroborating the data that has demonstrated that the immune system of MM is impaired and, therefore, the immunotherapies that have been studied recently for the treatment of the disease are extremely necessary in the search for a control and a cure for these patients who live with the disease.