Bacteria are not only ubiquitous on earth but can also be incredibly diverse within clean laboratories and reagents. The presence of both living and dead bacteria in laboratory environments and ...reagents is especially problematic when examining samples with low endogenous content (e.g., skin swabs, tissue biopsies, ice, water, degraded forensic samples or ancient material), where contaminants can outnumber endogenous microorganisms within samples. The contribution of contaminants within high‐throughput studies remains poorly understood because of the relatively low number of contaminant surveys. Here, we examined 144 negative control samples (extraction blank and no‐template amplification controls) collected in both typical molecular laboratories and an ultraclean ancient DNA laboratory over 5 years to characterize long‐term contaminant diversity. We additionally compared the contaminant content within a home‐made silica‐based extraction method, commonly used to analyse low endogenous content samples, with a widely used commercial DNA extraction kit. The contaminant taxonomic profile of the ultraclean ancient DNA laboratory was unique compared to modern molecular biology laboratories, and changed over time according to researcher, month and season. The commercial kit also contained higher microbial diversity and several human‐associated taxa in comparison to the home‐made silica extraction protocol. We recommend a minimum of two strategies to reduce the impacts of laboratory contaminants within low‐biomass metagenomic studies: (a) extraction blank controls should be included and sequenced with every batch of extractions and (b) the contributions of laboratory contamination should be assessed and reported in each high‐throughput metagenomic study.
Forensic dental autopsy is a fundamental procedure for the study of a death under judicial investigation in the search for postmortem (PM) information that can be compared with the antemortem (AM) ...data available from the cadaver. One of the major difficulties in taking postmortem evidence is the opening of the mouth, limited in many cases by the phenomenon of cadaveric rigidity or rigor mortis. The aim of this study was to evaluate the effectiveness of a new device designed to facilitate the opening of the dental arches in rigor mortis corpses. For this purpose, a sample of 30 corpses (22 men and 8 women; mean age 42.18 years and 38.75 years) from the Institute of Legal Medicine of the city of Lima (Peru) was analyzed. A forensic odontologist designed and manufactured the apparatus and carried out the sample analysis process. The initial and maximum measurements of oral cavity opening were recorded and a paired Student's t-test was applied to observe the difference between these initial and maximum measurements obtained (p < 0.05). The results showed that the average oral opening obtained with the new appliance was 43.83 ± 3.62 mm, with an average initial opening of 6.49 ± 3.04 mm (p < 0.001). The efficacy was similar in men and women (maximum opening M: 51.70 mm - F: 53.00 mm). In 29 of the 30 carcasses studied (96.7%) an opening greater than 40 mm was obtained, the latter being a minimum measurement sufficient to access the oral cavity. The efficacy of this new instrument for oral autopsy purposes is highlighted, since it does not cause destruction of the soft tissues and allows the correct manipulation of the oral structures present.
•Forensic odontological autopsy is a procedure to obtain valuable information of a death under judicial investigation.•A new device to facilitate the opening of the dental arches in rigor mortis corpses was developed and tested.•A sample of 30 corpses (22 men and 8 women; mean age 42.18 years and 38.75 years) was analyzed.•In 29 of the 30 cadavers studied (96.7%) an opening greater than 40 mm was obtained.•This useful device fulfilled their required function in a forensic odontological autopsy.
Despite a growing catalog of secreted factors critical for lymphatic network assembly, little is known about the mechanisms that modulate the expression level of these molecular cues in blood ...vascular endothelial cells (BECs). Here, we show that a BEC‐specific transcription factor, SOX7, plays a crucial role in a non‐cell‐autonomous manner by modulating the transcription of angiocrine signals to pattern lymphatic vessels. While SOX7 is not expressed in lymphatic endothelial cells (LECs), the conditional loss of SOX7 function in mouse embryos causes a dysmorphic dermal lymphatic phenotype. We identify novel distant regulatory regions in mice and humans that contribute to directly repressing the transcription of a major lymphangiogenic growth factor (Vegfc) in a SOX7‐dependent manner. Further, we show that SOX7 directly binds HEY1, a canonical repressor of the Notch pathway, suggesting that transcriptional repression may also be modulated by the recruitment of this protein partner at Vegfc genomic regulatory regions. Our work unveils a role for SOX7 in modulating downstream signaling events crucial for lymphatic patterning, at least in part via the transcriptional repression of VEGFC levels in the blood vascular endothelium.
Synopsis
Blood endothelial cells guide patterning of lymphatic vasculature via expression of various signaling molecules. This study reports the role of the blood vascular endothelial‐specific transcription factor, SOX7, as a key driver of dorso‐lateral patterning of lymphatic vessels during development by repressing VEGFC transcription.
SOX7 deletion in blood vascular endothelial cells in mice causes lymphoedema and ectopic lymphangiogenesis.
Loss of SOX7 function upregulates Vegfc transcript levels in arterial endothelial cells.
SOX7 represses VEGFC transcription via the Notch pathway and by directly binding to the Vegfc locus.
Loss of SOX7 function expands the lymphatic endothelial cell progenitor pool and disturbs their distribution, similar to VEGFC gain‐of‐function.
SOX7 represses transcription of the lymphangiogenic factor VEGFC in the blood vascular endothelium to maintain proper patterning of lymphatic vessels.
To compare the root and alveolar bone changes in first premolars adjacent to the orthodontic traction of buccal versus palatal maxillary impacted canines (MIC).
Before and after traction, cone beam ...tomographic computed (CBCTs) of 25 subjects with unilateral/bilateral MIC were included in this follow-up and retrospective study. Thirty-six first premolars were divided into 2 groups, buccal (n = 15) or palatal (n = 21) MIC, and the tomographic images were evaluated before and after orthodontic traction. Root changes in length and area were measured in sagittal, coronal and axial sections. Dimensions of alveolar bone were evaluated in coronal sections. Intergroup and intragroup comparisons were performed using t or Mann-Whitney U tests. Multiple linear regressions analyses were used to evaluate the influence of all predictor variables on root and alveolar bone changes (P<0.05).
Root and alveolar bone changes produced by orthodontic traction were not significant between groups. Root changes were smaller than 1 mm (length) and 2.51 mm2 (area). Alveolar bone changes between buccal and palatal MIC groups ranged from 0.13 mm to 1.69 mm Furthermore, the multivariate analysis showed no significant influence of the impaction condition (buccal or palatal) on root change. Nevertheless, some different predictor variables of the MIC influence these changes. In the alveolar bone, the maximum upper alveolar width (MUAW) is the most affected by the traction of the MIC.
Orthodontic traction of buccal vs palatal MIC produces similar resorptive and appositional root and alveolar bone changes in the adjacent first premolars, without clinical relevance.
Aim
To develop, apply, and evaluate a virtual learning object (VLO) for teaching undergraduate dental students and paediatric dentists to diagnose and manage molar incisor hypomineralization (MIH).
...Design
This controlled educational intervention included 170 undergraduate dental students and 50 paediatric dentists. The student intervention group (VLOG) was trained by the VLO, the control group of students (CG) received a synchronous virtual class, and the group of paediatric dentists (PDG) was trained by the VLO. Pre‐test and post‐test data were analyzed with a mixed one‐way and Tukey’s post hoc ANOVA test (α = 0.05). The answers to the questionnaire were analyzed with the one‐way ANOVA test and Tukey's post hoc test (α = 0.05).
Results
The values obtained in the pre‐test were significantly lower than those obtained in the post‐test for all groups. The specialists showed a higher level of knowledge before and after the MIH training compared with the students (p < .001). Similarly, statistical differences were found in the level of knowledge, which increased after MIH training (p < .001). There were no differences between the CG and VLOG.
Conclusions
The level of knowledge increased in all groups after training regardless of the method used. VLOG works similar to traditional teaching approaches.
This single-center trial aimed to longitudinally compare the oral health-related quality of life (OHRQOL), adaptation and discomfort during anterior open bite (AOB) treatment with lingual spurs and ...build-ups (SBU) versus spurs only (S) approaches. Children (7-11 years) with AOB were randomly allocated into two treatment groups (SBU or S). The Child Perception Questionnaire (CPQ
) was applied 1 and 12 months after installation of the appliances. Questionnaires evaluating functional adaptation and discomfort during the first month of treatment were also applied. A visual analog scale (VAS) was used in these questionnaires. Generalized mixed models were used for analyzing OHRQOL and discomfort data. Generalized linear models were used to assess adaptation outcomes (α = 0.05). The SBU group included 24 patients (7 males and 17 females; mean age 8.2 years) and the S group included 25 patients (11 males and 14 females; mean age 8.3 years). Regardless of the treatment type, overall OHRQOL scores at 12 months were 0.69 times those recorded at 1 month after the appliances installation (i.e., ~ 31% reduction; exp (β) = 0.69; 95% CI: 0.55, 0.88). A significant interaction between treatment and time was detected for the 'functional limitations' domain. For this domain, a significant improvement from the first to the twelfth month was observed in the S group (P < 0.001). Patients in both treatment groups showed similar and easy adaptation to the appliances. Independent of the type of treatment, tongue-related discomfort decreased over time. One week and one month after the appliance's delivery, the discomfort scores were 0.19 (i.e., ~ 81% reduction; exp (β) = 0.19; 95% CI: 0.13, 0.28; P < 0.001) and 0.02 (i.e., ~ 98% reduction; exp (β) = 0.02; 95% CI: 0.01, 0.07; P < 0.001) times, respectively, those issued immediately after the installation of the appliances. Regardless of treatment type; overall OHRQOL improved from the first to the twelfth month of AOB treatment. The functional limitations score decreased in the S group. Children showed easy adaptation, and their discomfort decreased 1 week after the installation of the appliances.Trial registration: Clinicaltrials.gov; NCT03702881, date of registration: October 11, 2018.
Objective
To compare and assess the reproducibility of 3 methods for registration of maxillary digital dental models in patients with anterior open bite.
Settings and sample population
Digital dental ...models of 16 children with an anterior open bite in the mixed dentition were obtained before (T1) and after 12 months of treatment with bonded spurs (T2).
Methods
Landmarks were placed on all T2 models and 3 registration methods (R1, R2 and R3) were independently performed by 2 observers. R1 was based on 10 landmarks placed on posterior teeth. R2 was based on 5 landmarks on the palate (2 anterior, 2 posterior and 1 central). R3 used regions of interest around the 5 palatal landmarks used in R2. The differences between the registration methods were calculated by comparing the mean differences and standard deviations between the corresponding x, y and z coordinates of 6 corresponding landmarks in the T2 registered models. Repeated measures analysis of variance followed by post‐hoc Bonferroni tests were used for comparisons (P < .05). The agreement between methods and the intra and interobserver reproducibility were assessed with Bland‐Altman tests and intraclass correlation coefficients (ICC).
Results
Comparisons of R2 with R3 methods showed greater agreement, mean differences ≤0.50 mm for all landmarks, than comparisons of R1 with R2, and R1 with R3, mean differences >0.50 mm for most of the y and z coordinates (P < .05). The R1 and R3 methods presented excellent intra and interobserver reproducibility and R2 method had moderate interobserver reproducibility.
Conclusions
Longitudinal assessments of open bite treatment using digital dental models could consider the posterior teeth and/or the palate as references. The R1 and R3 methods showed adequate reproducibility and yield different quantitative results. The choice will depend on the posterior teeth changes and dental models’ characteristics.
This randomized clinical trial aimed to compare the three-dimensional dentoalveolar maxillary changes after anterior open bite treatment with bonded spurs and build-ups versus bonded spurs alone. ...Patients from 7 to 11 years of age with anterior open bite were randomly allocated into two groups. Bonded spurs and posterior build-ups were used in the experimental group and only bonded spurs were used in the comparison group. The randomization sequence was generated at www.randomization.com . Opaque, sealed and sequentially numbered envelopes were part of the allocation concealment. Digital dental models were acquired before (T1) and after 12 months of treatment (T2) and de-identified for analysis purposes. Three-dimensional changes of maxillary permanent incisors and first molars were evaluated by means of T1 and T2 dental model superimposition. Landmark-based registration on the posterior teeth and registration on the palate using regions of interest were performed. T or Mann-Whitney U tests were used for intergroup comparisons (P < 0.05). Mean difference (MD) and 95% confidence interval (CI) were calculated. Twenty-four children (17 girls and 7 boys) were included in the experimental group (mean age 8.22 ± 1.06 years) and 25 children (14 girls and 11 boys) were included in the comparison group (mean age 8.30 ± 0.99 years). After 12 months of treatment, inferior displacements of maxillary incisors were similar in the experimental (1.55-2.92 mm) and comparison (1.40-2.65 mm) groups. Inferior displacement of the maxillary molars was also similar in both groups (MD: - 0.13 mm; 95% CI - 0.38, 0.12). The experimental and comparison groups showed medial and lateral displacements of the permanent first molars, respectively (MD, - 0.31 mm; 95% CI - 0.51, - 0.11). Lingual inclination of the permanent first molars were observed in the experimental group and buccal inclination in the comparison group (MD, - 2.16°; 95% CI - 3.72, - 0.60). Similar three-dimensional displacements of maxillary central and lateral incisors, and inferior displacements of maxillary permanent first molars were observed in both groups. Bonded spurs associated with posterior build-ups demonstrated some medial displacement and lingual inclination of the maxillary permanent first molars while opposite changes were noticed in the comparison group.Trial registration: Clinicaltrials.gov; NCT03702881, date of registration: October 11, 2018.
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