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Independent vector analysis (IVA) can be viewed as an extension of independent component analysis (ICA) to multiple datasets. It exploits the statistical dependency between different datasets through mutual information. In the context of motor imagery classification based on electroencephalogram (EEG) signals for the brain–computer interface (BCI), several methods have been proposed to extract features efficiently, mainly based on common spatial patterns, filter banks, and deep learning. However, most methods use only one dataset at a time, which may not be sufficient for dealing with a multi-source retrieving problem in certain scenarios. From this perspective, this paper proposes an original approach for feature extraction through multiple datasets based on IVA to improve the classification of EEG-based motor imagery movements. The IVA components were used as features to classify imagined movements using consolidated classifiers (support vector machines and K-nearest neighbors) and deep classifiers (EEGNet and EEGInception). The results show an interesting performance concerning the clustering of MI-based BCI patients, and the proposed method reached an average accuracy of 86.7 % . [ABSTRACT FROM AUTHOR]

Background: Eccentric instruments have been proposed as more effective and less time‐consuming for endodontic instrumentation. Aim: To compare biomechanical outcomes of different instrumentation systems and time undertaken for instrumentation in resin prototypes. Design: Sixty standardized prototypes of mandibular second primary molars were instrumented according to the following systems: K‐files, ProTaper Next (PTN), XP‐endo Shaper (XPS), XP‐endo Finisher (XPF), XP–Clean (XPC), and Sequence Baby File (SBF; n = 10/each). Irrigation was performed with saline with simultaneous aspiration, and time spent was recorded. The prototypes were micro‐CT‐scanned before and after the instrumentation, and image sets were reconstructed and registered. Non‐instrumented areas, accumulated debris, removed root material volume, and canal transportation were quantified. Data were analyzed through ANOVA, the Kruskal–Wallis test, and the Wilcoxon signed‐rank test (α = 5%). Results: K‐files and SBF resulted in more instrumentation time (p <.05). SBF, XPC and PTN removed less root dentine (p <.05), but PTN left more untouched areas (p <.05). Accumulated debris were lower for XPC and SBF (p <.05). Canal transportation was similar among the groups. Conclusion: Rotary systems reduced instrumentation time, whereas SBF and XPC resulted in more conservative instrumentation, with less debris accumulation and non‐instrumented areas. A dedicated paediatric endodontic system (SBF) outperformed eccentric instruments in terms of effectiveness. [ABSTRACT FROM AUTHOR]

Background: Molar hypomineralization (MH) is defined as a multifactorial condition, and thus, its presence may be defined by interactions between environmental and genetic factors. Aim: To evaluate the association between MH, genes involved in enamel development, and the use of medication during pregnancy in early childhood. Design: One hundred and eighteen children, 54 with and 64 without MH, were studied. The data collected included demographics, socioeconomic data, and the medical history of mothers and children. Genomic DNA was collected from saliva. Genetic polymorphisms in ameloblastin (AMBN; rs4694075), enamelin (ENAM; rs3796704, rs7664896), and kallikrein (KLK4; rs2235091) were evaluated. These genes were analyzed by real‐time polymerase chain reaction using TaqMan chemistry. The software PLINK was used to compare allele and genotype distributions of the groups and to assess the interaction between environmental variables and genotypes (p <.05). Results: The variant allele KLK4 rs2235091 was associated with MH in some children (odds ratio [OR]: 3.75; 95% confidence interval [CI] = 1.65–7.81; p =.001). Taking medications in the first 4 years of life was also associated with MH (OR: 2.94; 95% CI = 1.02–6.04; p =.041) and specifically in association with polymorphisms in ENAM, AMBN, and KLK4 (p <.05). The use of medications during pregnancy was not associated with MH (OR: 1.37; 95% CI = 0.593–3.18; p =.458). Conclusion: The results of this study suggest that taking medication in the postnatal period appears to contribute to the etiology of MH in some evaluated children. There may be a possible genetic influence of polymorphisms in the KLK4 gene with this condition. [ABSTRACT FROM AUTHOR]

Objective: To identify the clinical presentation of molar incisor hypomineralization (MIH) and hypomineralization of second primary molars (HSPM), including the distribution patterns of presence and severity of lesions, and to investigate the association of risk factors during the pre-and postnatal period with the presence of lesions. Material and Methods: This cross-sectional study was conducted with 160 individuals (72 with MIH/HSPM and 88 without lesions). The symmetry analysis regarding the presence and severity of MIH/HSPM was evaluated in pairs of homologous and opposite teeth. Sociodemographic and medical information was obtained using a detailed questionnaire. Data were analyzed by means of chi-square tests, Student’s t-test, and logistic regression (p<0.05). Results: Symmetry of presence and severity of hypomineralization lesions were present in homologous permanent teeth in 53.8% and 70.5% of cases, respectively, with statistically significant results only for the symmetrical pattern of severity of MIH lesions in the maxillary first molars (p=0.016) and mandibular first molars (p=0.02). Otherwise, a non-symmetric presence was statistically significant in homologous second primary molars (p=0.002) and opposite primary and permanent teeth (p≤0.001). An association between MIH/HSPM and systemic diseases during pregnancy and children medication was found (p<0.05); however, no evidence was found between these and MIH/HSPM severity. Conclusion: The symmetric pattern of severity of MIH lesions was statistically significant in permanent homologous teeth. Risk factors during pre and postnatal periods may be related to MIH/HSPM; however, these do not seem to interact with severity. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the cost‐effectiveness of retaining one or more compromised first permanent molars (cFPMs) affected by dental caries or enamel hypomineralization, compared to timely extraction, in children aged 8 years. Methods: A Markov model was developed to simulate the lifetime of a cFPM. Two management strategies were compared: extraction facilitating spontaneous space closure or maintenance of teeth with restorations. Ten health states were utilized to capture long‐term outcomes including various tooth restorations, prostheses or a retained gap at the cFPM site. Outcomes were expressed as Quality Adjusted Tooth‐Years (QATYs). The model was informed by survey data on patient preferences for treatment outcomes and UK data on costs. Discounted costs and QATYs were calculated over 62 years. Results: Regardless of the number of cFPMs, retaining cFPMs was more effective than early removal, generating an additional 2.3 QATYs per cFPM. Early removal of one or two cFPM under general anaesthetic (GA) was more expensive than retention and hence never cost‐effective. Retaining a cFPM was more expensive than early removal under local anaesthesia or where four cFPMs were extracted under GA. In these cases, retaining cFPMs was cost‐effective if a QATY was valued at £100 or £35, respectively. Results were robust to sensitivity analysis. Conclusion: Preserving a cFPM was more cost‐effective than the early loss of one, or two cFPMs under GA. Preservation of four cFPMs was cost‐effective if sufficient value was placed on a QATY. These findings can guide clinical practice on management of cFPMs alongside patient/payer values on maintaining teeth. [ABSTRACT FROM AUTHOR]

Objective: To associate caregivers' sense of coherence (SOC) and untreated caries with oral health status in children covered by a dental public health system. Material and Methods: A convenience sample of caregivers/children in Angra dos Reis, Brazil, was surveyed. Caregivers' SOC was evaluated using the 13- question version questionnaire. For both caregivers/children, sociodemographic information was acquired and caries experience was evaluated by DMFT/dmft and PUFA/pufa index. Statistical associations between children's untreated carious teeth and interest variables from the caregivers were evaluated by binary logistic regression assessed by generalized linear modeling. Results: A total of 233 pairs of caregivers-children were included. Children's untreated permanent and primary carious teeth represented 34.8% and 62.2% of the caries experience, respectively and at least one PUFA/pufa scored tooth was detected in 22.7% of them. Caregivers' DMFT was 13.5±7.0, while 33.6% scored on PUFA. A total of 62.1% of them presented untreated carious lesions. Results from the univariate model, correlating children's untreated caries and caregivers' attributes showed a statistical significance for SOC values (p<0.015), untreated decayed teeth (p<0.035), self-perception of oral health (p<0.022) and oral impact on daily performance (p<0.010). The multivariate logistic first model kept the statistical significance only for the caregiver's untreated decayed teeth. Conclusion: Caregivers' SOC and untreated carious teeth could be used as indicators of dental treatment needs in their offspring. [ABSTRACT FROM AUTHOR]

Objective: To compare the agreement of images in white light (WL), fluorescence (FL), and digital radiographs (DR), on the diagnosis and treatment decisions for occlusal caries lesions against a micro-CT gold standard. Material and Methods: Ten extracted third molars, with enamel and/or dentin caries (ICDAS 2-4), were included. Occlusal surface images were acquired with an intraoral camera (SoproLife®) in WL and FL modes. DR was obtained using an intraoral X-ray and a semi-direct digital system. A total of 780 images were needed, organized in a template, to be later examined by twenty-six dentists invited to compose the study. The Generalized Estimation Equations model was used to compare the proportions of the correct answers between the three methods and the gold standard. When significant, Bonferroni post-hoc test was used to identify differences (α=5%). Results: Most of the examiners were specialists (76.9%) with 14.5 years of experience. All diagnostic methods were similar and showed low agreement (DR 12.7%, WL 16.5%, and FL 16.5%) compared with gold standard caries diagnostic scores. Regarding treatment decisions, mean agreement for all diagnostic methods was higher (43.2%; p<0.001), and among all methods, WL (48.1%) and FL (51.2%) modes performed better than DR (30.4%, p<0.001). Conclusion: SoproLife® images could help clinicians to propose rational, minimally invasive treatments for occlusal caries lesions. [ABSTRACT FROM AUTHOR]