CAMBIAMENTI TRIDIMENSIONALI DEL MASCELLARE SUPERIOREDOPO ESPANSIONE CON LEAF EXPANDER® IN UN CAMPIONEDI PAZIENTI IN ETA¿ EVOLUTIVA.VALUTAZIONE MEDIANTE SOVRAPPOSIZIONE DI MODELLI DIGITALI E DI CTBC

Scopo del lavoro: valutare le modificazioni trasversali delle arcate ottenuti con un\u2019espansione lenta, con forze leggere ed alto controllo del movimento, su un campione di pazienti in crescita, con insufficienza trasversale del mascellare. Materiali e Metodi: sono stati inclusi nello studio n\ub0 10 pazienti (n\ub0 3 maschi, n\ub0 7 femmine) con un\u2019et\ue0 media di 7 anni 5 mesi +/- 7 mesi, trattati con espansione mascellare lenta per la correzione di crossbite posteriore monolaterale (con shift mandibolare), mediante il dispositivo denominato Leaf Expander (L.E.), ancorato sui secondi molari decidui. Su questo campione di n\ub010 pazienti sono stati eseguiti due diversi Studi Pilota. - Studio Pilota I In tutti i pazienti (n\ub010) sono stati realizzati modelli digitali delle arcate dentarie prima dell\u2019inizio del trattamento (T1) e a fine terapia, al momento della rimozione dell\u2019espansore L.E. (T2). I modelli sono stati analizzati rilevando n\ub05 parametri lineari: 1) distanza intermolare sup. (molari permanenti) 2) distanza intermolare sup. (molari decidui) 3) distanza intercanina superiore 4) distanza intermolare inferiore (molari permanenti) 5) distanza intercanina inferiore - Studio Pilota II In n\ub0 5 pazienti, con deficit di spazio a carico dei canini superiori, \ue8 stata effettuata una tomografia computerizzata cone beam (CBCT) prima dell\u2019inizio del trattamento (T1), seguita da una CBCT al momento della rimozione del L.E. (T2). Sono state eseguite misurazioni e sovrapposizioni al fine di valutare n\ub0 3 parametri, i pi\uf9 significativi secondo la letteratura: 1) ampiezza nasale 2) ampiezza mascellare a livello dei II molari decidui 3) ampiezza mascellare a livello di primi molari permanenti Risultati: In tutti i pazienti si \ue8 realizzata la correzione del crossbite posteriore, con 4 mesi di trattamento in media. Tutti i parametri oggetto di valutazione, dentali e scheletrici, relativi all\u2019arcata superiore, sono aumentati significativamente durante la fase di espansione lenta mascellare. Il percorso eruttivo e la prognosi dei canini inclusi risultano migliorati. Per quanto riguarda l\u2019arcata mandibolare abbiamo rilevato la riduzione del diametro intermolare 6-6 e l\u2019incremento del diametro intercanino. Conclusioni: i risultati dei due Studi Pilota convalidano l\u2019efficacia dell\u2019espansore lento Leaf Expander, nel trattamento delle insufficienze trasversali del mascellare, nel giovane paziente, con azione sia dentoalveolare sia scheletrica.Aim of the researche: The purpose of this study was to evaluate and compare the dental and bone effects of slow maxillary expansion, with low forces and hight movement control, in a sample of young patients with unilateral transversal maxillary deficiency, with mandibular shift. Materials and method: have been included in the study 10 patients (n\ub0 3 male, n\ub0 7 female) with an average age of 7.5 yrs +/- 7, treated with a slow maxillary expansion by Leaf Expander appliance . - Pilot Study I: for all ten patients, the digital models have been made at the beginning of the therapy (T1), at the end of expansion (T2). Five parameters have been measured with the cast analysis: 1) the distance between the first upper permanent molars 2) the distance between the upper second deciduous molars 3) the distance between the upper canine cusps 4) the distance between the lowers molars 5) the distance of the lower canine cusps. - Pilot Study II: for only 5 patients, with loss of space for upper cusps, a cone beam computed tomography (CBCT) have been performed at the beginning of the therapy (T1) and after expansion (L.E. remotion) (T2). Misurations and superimpositions have been performed to evaluate the three parameters, most relevant on basis of literature: 1) nasal width 2) basal bone 3) intermolar diameter at II deciduous molars Results: In all the patients the complete correction of posterior crossbite has been achieved in 4 monts, on average. Significant increases in the dental and skeletal transversal diameters were obtained with slow maxillary expansion. Increases were also obtained about anterior mandibular arch (+ 1mm). Conclusions: the Pilot Studys performed confirm the soundness of Leaf Expander appliance in the transversal deficiency correction with a both dental-alveolar and skelectal action in the treatment of young patients

Three-dimensional evaluation of rapid maxillary expansion anchored to primary molars: Direct effects on maxillary arch and spontaneous mandibular response

Aim The purpose of this study was to evaluate the effects of rapid maxillary expansion (RME) on maxillary and mandibular arch in the mixed dentition. Methods Forty-four consecutive patients with transverse maxillary deficiency were recruited. Test group: 21 patients (10 male, 11 female; 7.4 \ub1 1.2 years) who underwent RME (Haas type) therapy banded on the primary second molars. Control group: 17 patients (10 male, 7 female; 7.3 \ub1 1.1 years old) who did not receive any orthodontic treatment. Dental casts obtained pre-treatment and after appliance removal (11 months) were processed by means of a three-dimensional scanner (3Shape D250 laser, DK). Digital landmarks were traced using the VAM software (Canfield Scientific Inc., Fairfield-NJ, USA). Arch Length, interdental width and torque differences were measured before and after the removal of the appliance. The t-test (P < 0.05) for paired data was applied to evaluate the measurements values before and after treatment. The linear regression model was employed to assess the correlations between treatment effects. Results The efficacy of the RME was confirmed both on maxillary and mandibular arch. Mandibular intermolar width (+2.02 mm) together with primary intermolar (+1.39 mm), intercanine width (+0.95mm) and torque variations significantly increased. The untreated control group showed no significant statistical differences between T0 and T1. The linear regression between maxillary and mandibular data showed correlations between the torque of the teeth 16/46 and 65/85 (P < 0.05). Conclusions RME anchored on primary molars is an effective treatment option to correct tranverse maxillary deficiencies. All the measurements increased significantly confirming the indirect effect of RME on the mandibular arch

A Domain Decomposition Approach to Finite Volume Solutions of the Euler Equations on Triangular Meshes

we report on our recent efforts on the formulation and the evaluation of a domain decomposition algorithm for the parallel solution of two-dimension- al compressible inviscid flows. The starting point is a flow solver for the Euler equations which is based on a combined finite element/finite volume formulation on unstructured triangular meshes for the spatial discretiz- ation. Time integration of the resulting semi-discrete equations is obtained using a linearized backward Euler implicit scheme. As a result, each pseudo time step requires the solution of a sparse linear system for the flow variables. In this study, a non-overlapping domain decomposition algorithm is used for advancing the solution at each implicit time step. First, we formulate an additive Schwarz algorithm using appropriate matching conditions at the subdomain interfaces. In accordance with the hyperbolic nature of the Euler equations, these transmission conditions are Dirichlet conditions for the characteristic variables corresponding to incoming waves. Then, we introduce interface operators that allow to express the domain decomposition algorithm as a Richardson type iteration on the interface unknowns. Algebraically speaking, the Schwarz algorithm is equivalent to a Jacobi iteration applied to a linear system whose matrix has a block structure. A substructuring technique can be applied to this matrix in order to obtain a fully implicit scheme in terms of interface unknowns. In our approach, the interface unknowns are numerical (normal) fluxes

A Non-Overlapping Domain Decomposition Method for Solving the Navier-Stokes Equations on Unstructured Triangular Meshes

we report on our recent efforts on the formulation and the evaluation of a non-overlapping domain decomposition method for the parallel solution of two-dimensional compressible viscous flows. This work extends a previous study [11] which was concerned with the design of a domain decomposition solver for the Euler equations discretized on unstructured triangular meshes. As in [11], the method relies on the formulation of an additive Schwarz type algorithm where the interface conditions express the continuity of the normal flux components. The starting point is a flow solver for the Navier-Stokes equations which is based on a combined finite element/finite volume formulation on unstructured triangular meshes for the spatial approxima- tion. Time integration of the resulting semi-discrete equations is performed by using a linearized backward Euler implicite scheme. As a result, each pseudo time step requires the solution of a sparse linear system for the flow variables. In this study, a non-overlapping domain decomposition algorithm is used for advancing the solution at each implicit time step. Algebraically speaking, the Schwarz algorithm is equivalent to a Jacobi iteration applied to a linear system whose matrix has a block structure. A substructuring technique can be applied to this matrix in order to obtain a fully implicit scheme in terms of interface unknowns. In our approach, the interface unknowns are numerical fluxes

Out of the forest: past and present range expansion of a parthenogenetic weevil pest, or how to colonize the world successfully

Previous research revealed complex diversification patterns in the parthenogenetic weevil Naupactus cervinus. To understand the origin of clonal diversity and successful spreading of this weevil, we investigated its geographic origin and possible dispersal routes and whether parthenogens can persist in habitats under unsuitable environmental conditions. This study is based on samples taken throughout a broad area of the species’ range. We used both mitochondrial and nuclear markers and applied phylogenetic and network analyses to infer possible relationships between haplotypes. Bayesian phylogeographic analyses and ecological niche modeling were used to investigate the processes that shaped genetic diversity and enabled the colonization of new geographic areas. Southeastern Brazil emerges as the original distribution area of N. cervinus. We detected two range expansions, one along natural corridors during the Pleistocene and the other in countries outside South America during recent times. Isolation due to climate shifts during the early Pleistocene led to diversification in two divergent clades, which probably survived in different refugia of the Paranaense Forest and the Paraná River delta. The origin of the clonal diversity was probably a complex process including mutational diversification, hybridization, and secondary colonization. The establishment of N. cervinus in areas outside its native range may indicate adaptation to drier and cooler conditions. Parthenogenesis would be advantageous for the colonization of new environments by preventing the breakup of successful gene combinations. As in other insect pests, the present distribution of N. cervinus results from both its evolutionary history and its recent history related to human activities.Facultad de Ciencias Naturales y Muse

Phylogenetic analysis of the Pantomorus-Naupactus complex (Coleoptera: Curculionidae: Entiminae) from North and Central America

We undertook the first cladistic analysis of the Pantomorus-Naupactus complex (Coleoptera: Curculionidae) from North and Central America, based on 35 species and 61 morphological characters, plus 1151 bp of the mtDNA COI and Cyt b genes. The morphological and the combined matrices analyzed with TNT yielded a single most parsimonious cladogram that allows recognition of two main lineages within the Pantomorus-Naupactus complex in North and Central America. One is represented by the species formerly placed in Phacepholis and the Pantomorus species group II sensu Sharp, ranging along the Pacific coast of Central America and Mexico and reaching the Great Plains of North America in the United States, yet not occurring in South America. The other lineage is represented by the species of Naupactus and Pantomorus: species group I, with closer relationships to the South American species of these genera. The Pantomorus group I includes the type species of the genus P. albosignatus Boheman whereas the Pantomorus group II includes the type species of Athetetes Pascoe, 1886 (A. globicollis Pascoe). Based on the results of our phylogenetic analysis, we recommend retaining the name Pantomorus Schoenherr for most species of the Pantomorus group I, except P. stupidus (Boheman) and P. femoratus Sharp which should be transferred to Naupactus Dejean. Moreover, we enlarge the previous concept of Phacepholis to include most species of the Pantomorus group II, and we establish the synonymy of Athetetes Pascoe, 1886 with Phacepholis Horn, 1876, being the latter the valid name, by priority.We undertook the first cladistic analysis of the Pantomorus-Naupactus complex (Coleoptera: Curculionidae) from North and Central America, based on 35 species and 61 morphological characters, plus 1151 bp of the mtDNA COI and Cyt b genes. The morphological and the combined matrices analyzed with TNT yielded a single most parsimonious cladogram that allows recognition of two main lineages within the Pantomorus-Naupactus complex in North and Central America. One is represented by the species formerly placed in Phacepholis and the Pantomorus species group II sensu Sharp, ranging along the Pacific coast of Central America and Mexico and reaching the Great Plains of North America in the United States, yet not occurring in South America. The other lineage is represented by the species of Naupactus and Pantomorus: species group I, with closer relationships to the South American species of these genera. The Pantomorus group I includes the type species of the genus P. albosignatus Boheman whereas the Pantomorus group II includes the type species of Athetetes Pascoe, 1886 (A. globicollis Pascoe). Based on the results of our phylogenetic analysis, we recommend retaining the name Pantomorus Schoenherr for most species of the Pantomorus group I, except P. stupidus (Boheman) and P. femoratus Sharp which should be transferred to Naupactus Dejean. Moreover, we enlarge the previous concept of Phacepholis to include most species of the Pantomorus group II, and we establish the synonymy of Athetetes Pascoe, 1886 with Phacepholis Horn, 1876, being the latter the valid name, by priority.Fil: Rosas, María V.. Universidad Nacional Autónoma de México; MéxicoFil: Morrone, Juan José. Universidad Nacional Autónoma de México; MéxicoFil: del Rio, Maria Guadalupe. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Lanteri, Analia Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentin

Correlation between dental vestibular-palatal inclination and alveolar bone remodeling after orthodontic treatment: A CBCT analysis

The aim of this study was to evaluate the correlation between dental vestibular-palatal inclination changes and the cortical bone remodeling after fixed orthodontic treatment using cone beam computed tomography (CBCT). Twenty-two patients with Angle Class I malocclusion, permanent dentition, and mild to moderate dental crowding were included in the present three-dimensional (3D) analysis. Bone dimensions were evaluated by CBCT scans obtained before and after orthodontic treatment, whereas the torque values were calculated by means of digital models using the 3D VistaDent software. A paired t-test was used to compare the changes between the pretreatment and post-treatment measurements. The correlations between variables were analyzed with linear regression analysis. A significant correlation between torque variations and bone thickness changes was observed for the apical buccal level of the anterior side (P < 0.05). Limited and not significant alveolar bone resorption for the apical thickness of anterior teeth occurred at \ub15 degrees of torque variation, while for tooth inclination exceeding +5 or-5 degrees, the bone remodeling was more evident. The present study demonstrated that anterior region was the most affected area by bone remodeling and that torque variation was highly related to apical bone thickness adaptation for maxillary and mandibular incisors and maxillary canines

A CBCT based analysis of the correlation between volumetric morphology of the frontal sinuses and the facial growth pattern in caucasian subjects. A cross-sectional study

open7noBackground: The aim of this study was to evaluate the relationship between frontal sinus shape and facial growth pattern. Methods: The three-dimensional examination was carried out by means of 80 CBCT scans selected from a sample of 1247 records of patients treated, for different reason, at the Department of Biomedical Surgical and Dental Sciences at University of Milan, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico Milan. The sample (age ranges between 12 and 40 years) was divided according to gender and age in four groups (12-17, 18-20, 21-30, 31-40). Left and right frontal sinus volume (VOL), surface (SUP) and linear maximum width (XMAX), depth (ZMAX) and height (YMAX) were calculated using Mimics Research 17.0 (Materialise N.V., Leuven, Belgium). Cephalometric analysis has been performed for all subjects to categorize the patients depending on their facial growth pattern. Univariate and multivariate regression analysis were performed to investigate any association of frontal sinuses measurements (height, width, depth, volume and surface) and cephalometric variables. P value < 0.05 was considered statistically significant. Results: A total of 160 frontal sinuses were measures in 80 patients: 40 men and 40 women, average age of 23.5 ±14.6. Globally the frontal sinuses had the following average dimensions: volumes of 9055.8 ± 6505 mm3 and surfaces of 3820.3 ± 2125 mm2. The statistical analysis showed that frontal sinus volume was statistically significant (p=0.003) greater for male (11,425 mm3) than female (6597.5 mm3). Similarly, the surface showed to be greater in men than in women (p=0.005). No correlation between age and frontal sinuses characteristics has been found. A statistically significant (p<0.05) increase of frontal sinus depth, surface and volume was correlated with SNB angle. In addition, frontal sinus volume increased in subjects with greater anterior skeletal dimension values and with a superior length of the cranial base. Furthermore, a decrease of ANB has been found related to an increase in frontal sinus volume (p=0.04). Conclusions: The present study showed a correlation between frontal sinuses dimensions and craniofacial aspects, despite the inter-individual variability of their morphology. The results suggested that young adults in whom the frontal sinuses have reached their maximum size, while vertical growth continues, a larger frontal sinus may be associated with future vertical growth.openAbate A.; Gaffuri F.; Lanteri V.; Fama A.; Ugolini A.; Mannina L.; Maspero C.Abate, A.; Gaffuri, F.; Lanteri, V.; Fama, A.; Ugolini, A.; Mannina, L.; Maspero, C

Comparison of a tridimensional cephalometric analysis performed on 3T-MRI compared with CBCT : a pilot study in adults

OBJECTIVE: Since the introduction of cone-beam computed tomography (CBCT) in dentistry, this technology has enabled distortion-free three-dimensional cephalometric analysis for orthodontic and orthognathic surgery diagnosis. However, CBCT is associated with significantly higher radiation exposure than traditional routine bidimensional examinations for orthodontic diagnosis, although low-dose protocols have markedly reduced radiation exposure over time. The objective of this preliminary feasibility study is to compare the accuracy and diagnostic capabilities of an already-validated three-dimensional cephalometric analysis on CBCT to those of an analysis on 3-T magnetic resonance imaging (3T-MRI) to assess whether the latter can deliver a comparable quality of information while avoiding radiation exposure. MATERIALS AND METHODS: In order to test the feasibility of three-dimensional cephalometry on 3T-MRI, 18 subjects (4 male; 14 female) with mean age 37.8\u2009\ub1\u2009SD 10.2, who had undergone both maxillofacial CBCT and maxillofacial 3T-MRI for various purposes within 1 month, were selected from the archive of the Department of Dentistry and Maxillofacial Surgery of Fondazione Ospedale Policlinico Maggiore, IRCCS, Milano, Italy. A three-dimensional cephalometric analysis composed of ten midsagittal and four bilateral landmarks and 24 measurements (11 angular, 13 linear) was performed on both scans using Mimics Research\uae v. 17.0 (NV, Technologielaan 15, 3001 Leuven, Belgium). Cephalometric analysis was performed twice by two independent orthodontists for each scan, and each orthodontist repeated the measurements 3 weeks later. Statistical analysis was performed with SPSS\uae 20.00 for Windows (IBM\uae Corporation, Sommers, NY, USA). A Bland-Altman test for each cephalometric value was performed to assess the agreement between the procedures. The intraclass correlation coefficient (ICC) was used to assess interobserver and intraobserver reliability. The coefficient of variation was used to evaluate precision. RESULTS: Both procedures showed good reliability, with mean intraobserver ICCs of 0.977/0.971 for CBCT and 0.881/0.912 for MRI. The average interobserver ICCs were 0.965 for CBCT and 0.833 for MRI. A Bland-Altman analysis for the cephalometric tracing revealed a similar range of agreement between the two modalities; the bias range (mean\u2009\ub1\u2009SD) was -\u20090.25-0.66\u2009mm (0.174\u2009\ub1\u20090.31) for distances and -\u20090.41-0.54\ub0 (0.12\u2009\ub1\u20090.33) for angles. CONCLUSIONS: Within the main limitation of this pilot study, that is, the small sample, it is possible to state that cephalometric measurements on 3T-MRI seem to possess adequate reliability and repeatability and that they show satisfying agreement with values measured on CBCTs. An MRI examination does not expose patients to ionizing radiation and could provide an alternative to CBCT for three-dimensional cephalometrics in the future