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- Klinge, Anna, et al.
(author)
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Craniofacial height in relation to cross-sectional maxillary and mandibular morphology
- 2017
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In: Progress in Orthodontics. - : Springer. - 1723-7785 .- 2196-1042. ; 18:32
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Journal article (peer-reviewed)abstract
- Background In order to gain a better understanding of how growth of the alveolar bone is linked to the vertical development of the face, the purpose of this study was to investigate if there is an association between the cross-sectional morphology of the maxillary and mandibular bodies with the craniofacial height, using images from cone beam computed tomography (CBCT). Methods From 450 pre-treatment CBCT scans, 180 were selected to be included in the study. Lateral head images were generated from the CBCT scans and were used to categorise subjects into three groups based on their vertical craniofacial height. Cross-sectional images from CBCT volumes were reformatted of the maxillary and mandibular bodies at five locations in the maxilla and five in the mandible. Each image was measured at one height and two width measurements. Statistical analysis performed was the one-way analysis of variance with a Tukey post hoc test. A significance level of 5% was used in all comparisons. Results Patients with large vertical craniofacial height had a significantly higher cross-sectional area both in the maxilla and in the mandible. In the same group, the cross-sectional area was significantly thinner in the mandible compared with the other two groups, especially in the anterior region. Conclusions This study further highlights the close relationship between craniofacial height and alveolar bone dimensions and contributes with important knowledge for planning and follow-up of comprehensive dental- and orthodontic treatments.
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| 2. |
- Ludwikow, Katarzyna, et al.
(author)
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Dentofacial characteristics of children and adolescents with foetal alcohol spectrum disorders: a comparison with matched controls
- 2023
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In: PROGRESS IN ORTHODONTICS. - : Springer-Verlag New York. - 2196-1042 .- 1723-7785. ; 24:1
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Journal article (peer-reviewed)abstract
- Background Foetal alcohol spectrum disorders (FASD) include somatic and neurological developmental disturbances after prenatal alcohol exposure, including facial anomalies. However, the knowledge of the orthodontic skeletal and dental cephalometric relations in this group is limited. The aim of the study was to assess the dentofacial characteristics of children and adolescents with FASD and to compare them with a matched control group.Methods The study group comprised all available children and adolescents diagnosed with FASD (> 7 years of age) in whom good quality cephalograms were available. The control group comprised non-syndromic, orthodontically untreated children with normal occlusion and skeletal relations matched with age and gender. Cephalometric analysis included eighteen linear and angular measurements. The general linear model for repeated measures regarding age, gender and the type of FASD was applied.Results The group with FASD included 35 individuals (21 girls and 14 boys) aged 7-18 years including 21 with foetal alcohol syndrome. The mean age in the study and the control group was 12.8 years (SD, range 3.2, 7.1-18.1) and 13.0 (SD, range 2.9, 9.1-18.1), respectively. Statistically significant differences between the groups were found in 15 out of 18 of the cephalometric measurements (83%). In children with FASD the mandible was more retrusive, the incisors were more proclined and the mandibular incisors and the lips were more protruded when compared with controls. There was no significant evidence of an influence of age, gender or FASD type.Conclusions Dentofacial characteristics of children and adolescents with FASD significantly differ from controls. Early orthodontic diagnosis and prophylaxis should play a part of the interdisciplinary care of patients in this group.
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| 4. |
- Abuohashish, Hatem, et al.
(author)
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Angiotensin(1-7) attenuates tooth movement and regulates alveolar bone response during orthodontic force application in experimental animal model.
- 2023
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In: Progress in orthodontics. - 2196-1042. ; 24:1
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Journal article (peer-reviewed)abstract
- Renin-angiotensin system and its ACE2/Ang(1-7)/Mas receptor axis regulates skeletal response to multiple physiological and pathological conditions. Recent research suggested a vital role of Ang(1-7) in regulating alveolar bone metabolism and remodeling. In this context, this study evaluated the effects of the Ang(1-7)/Mas receptor axis on orthodontic tooth movement (OTM) and the alveolar bone response to mechanical load.A coil spring was placed between the right maxillary first molar and the anterior tooth of Wistar rats to apply bidirectional mechanical force. Ang(1-7) with or without a specific Mas receptor antagonist (A779) was infused using subcutaneous osmotic pumps (200 and 400 ng/kg/min: respectively). Animals were killed after 5 and 14 days from the OTM procedure after the clinical evaluation of tooth movement and mobility. Morphometric analysis of alveolar bone structure was conducted using micro-CT and the histological picture was evaluated after H&E staining. Moreover, collagen fiber distribution was assessed using Picro-Sirius red stain. In addition, bone samples were collected from the pressure and tension sites around the anterior tooth for gene expression analysis.Ang(1-7) infusion suppressed the tooth movement and mobility after 14 days of the orthodontic force application. Additionally, Ang(1-7) infusion preserved the morphometric and histological structure of the alveolar bone at pressure and tension sides. These effects were abolished by adding A779 infusion. Collagen fiber distribution was dysregulated mainly by the A779 Mas receptor blockage. Ang(1-7) affected the bone formation, remodeling- and vascularity-related genes in the pressure and tension sides, suggesting a prominent suppression of osteoclastogenesis. Ang(1-7) also improved osteoblasts-related genes on the tension side, whereas the osteoclasts-related genes were augmented by A779 on the pressure side.Collectively, the activation of Ang(1-7)/Mas receptor axis appears to hinder tooth movement and regulates alveolar bone remodeling in response to mechanical force.
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| 5. |
- Alamadi, E., et al.
(author)
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A comparative study of cone beam computed tomography and conventional radiography in diagnosing the extent of root resorptions
- 2017
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In: Progress in Orthodontics. - : Springer Science and Business Media LLC. - 2196-1042. ; 18, s. 1-8
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Journal article (peer-reviewed)abstract
- Root resorptions are assessed and diagnosed using different radiographical techniques. A comparison of the ability to assess resorptions on two-dimensional (2D) and three-dimensional (3D) radiographs is, hitherto, lacking. The aims of this study were to evaluate the accuracy of 2D (periapical radiographs, PA and panoramic radiograph, PAN) and 3D (cone beam computed tomography, CBCT) radiographic techniques in measuring slanted root resorptions compared to the true resorptions, a histological gold standard, in addition to a comparison of all the radiographic techniques to each other. Radiographs (CBCT, PA, and PAN), in addition to histological sections, of extracted deciduous canines from thirty-four patients were analyzed. Linear measurements of the most and least resorbed side of the root, i.e., "slanted" resorptions, were measured using an analyzing software (Facad A (R)). For classification of slanted root resorptions, a modified Malmgren index was used. PAN underestimated the root length on both the least and most resorbed side. Small resorptions, i.e., low modified Malmgren scores, were more difficult to record and were only assessed accurately using CBCT. The root resorption scores were underestimated using PA and PAN. In assessment of linear measures, PAN differed significantly from both CBCT and PA. CBCT is the most accurate technique when measuring and scoring slanted root resorptions.
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| 6. |
- Schatz, J. P., et al.
(author)
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Large overjet as a risk factor of traumatic dental injuries: a prospective longitudinal study
- 2020
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In: Progress in Orthodontics. - : Springer Science and Business Media LLC. - 2196-1042. ; 21:1
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Journal article (peer-reviewed)abstract
- Purpose The aim of this longitudinal prospective study was to evaluate if schoolchildren with large overjet experience a greater risk of traumatic dental injuries (TDI) compared to children with normal or small overjet. Methods A sample of children aged 6-13 years was prospectively evaluated after 1 year: from the initial sample, data concerning trauma cases of 1413 children were collected to determine the number and types of injuries, the influence of overjet on the risk of TDI, and the relationships between trauma, age, and gender. Results The observed prevalence of trauma was higher for boys, with the largest frequency between the ages of 8 to 12 years: 67.9% of all injuries were hard tissue injuries and 32.1% subluxation and luxation injuries. Children with an overjet of 6 mm or more showed a statistically increased risk of getting trauma [RR = 3.37 with CI (1.81; 6.27)]. Conclusion In this prospective study, overjet stood out among variables as the most significant risk factor of TDI: an increased overjet of 6 mm or more had a major impact on the risk of trauma, which would speak in favor of early orthodontic correction of an increased overjet to reduce the prevalence of dental trauma
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| 7. |
- Fougeres, Chloe, et al.
(author)
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Search for Na-22 in novae supported by a novel method for measuring femtosecond nuclear lifetimes
- 2023
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In: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
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Journal article (peer-reviewed)abstract
- Classical novae are thermonuclear explosions in stellar binary systems, and important sources of Al-26 and Na-22. While ? rays from the decay of the former radioisotope have been observed throughout the Galaxy, Na-22 remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV ?-ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The Na-22(p, ?)Mg-23 reaction remains the only source of large uncertainty about the amount of Na-22 ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in Mg-23. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the Mg-23 states, places strong limits on the amount of Na-22 produced in novae and constrains its detectability with future space-borne observatories. The authors report a particle-particle correlation and velocity-difference profile method to measure nuclear lifetime. The results obtained for excited states of 23Mg are used to constrain the production of 22Na in the astrophysical novae explosions.
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