Plan d’occlusion: Mythe architectural ou mythe proprioceptif?

From two radiographic pictures of the head in profile, in meantime of few years, with the same person, the author proves that occlusal plane doesn’t vary during growth in comparison with the pterygo-clivien compass (Stable zone leasing against pterygoïd process and superior clivus).The orientation of occlusal plane crossing by contact of the first molars and the middle of incisive intersection has an approximately analogous value. This value is equal to 110 degrees for the sample population, whatever the person’s morphology and the lapsed time is. The occlusal plane moves parallel to himself and gets lower on a sagittal téléradiographic picture.From two radiographic pictures of the head in profile, in meantime of few years, with the same person, the author proves that occlusal plane doesn’t vary during growth in comparison with the pterygo-clivien compass (Stable zone leasing against pterygoïd process and superior clivus).The orientation of occlusal plane crossing by contact of the first molars and the middle of incisive intersection has an approximately analogous value. This value is equal to 110 degrees for the sample population, whatever the person’s morphology and the lapsed time is. The occlusal plane moves parallel to himself and gets lower on a sagittal téléradiographic picture

Climate-related default probabilities

Climate risk refers to the risks associated with climate change and has already started to impact various sectors of the economy. In this work, we focus on the impact of physical risk on the probability of default for a firm in the agribusiness sector. The probability of default is estimated based on the Merton model, where the firm defaults when its asset value falls below the threshold defined by its liabilities. We study the relationship between the stock value of the firm and global surface temperature anomalies, observing that an increase in temperature negatively affects the stock value and, consequently, the asset value of the firm. A decrease in the asset value of the firm translates into an increase in its probability of default. We also propose a model to assess the exposure of the firm to transition risk

Hedging at-the-money digital options near maturity

Hedging at-the-money digital options near maturity, remains a challenge in quantitative finance. In the present work, we carry out a hedging strategy by means of a bull spread. We study the probability of super- and sub-hedge the digital option and minimize the probability of a sub-hedge considering the cost of hedging and illiquidity issues. We perform a wide variety of numerical experiments under different models for the underlying asset dynamics. A calibration to market data is provided and used to get the optimal composition of the bull spread satisfying the cost of hedging restriction (...

Influence du développement vertical du massif facial supérieur sur les différents composants palatins

We put the vertical rotations of the premaxilla and of the hard palate in relation with the vertical development of the maxillary fied. The latter has been evaluated by the changes of length of the right segment that was defined by the prof. Delaire point and its MH1 projection of the hard palate.The vertical variations of the maxillary fields, evaluated from the M-MH1, have an influence on the orientation of the hard palate and the premaxilla in relation to the angle of the pterygoclivian compass.This action is very perceptible at the level of the premaxilla-palatinal junction. It is lower at the level of the hard palate and of the premaxilla when these are separately studied.We got the impression that the front and the back nasal thorns are relatively steady zones during the growth compared to the premaxillo-palatinal junction.Nous avons mis en relation les rotations dans le sens vertical du prémaxillaire et des lames palatines avec le développement vertical du champ maxillaire. Celui-ci a été évalué par les changements de longueur du segment de droite défini par le point M. de DELAIRE et sa projection MH1 sur les lames palatines.Les variations verticales du champ maxillaire, évaluées à partir de MMH1 influencent l'orientation des lames palatines et du prémaxillaire par rapport au compas ptérygo-clivien. Cette action est fort sensible au niveau de la jonction prémaxillo-palatine. Elle est moindre au niveau des lames palatines et du prémaxillaire lorsque ceux-ci sont étudiés séparément.Nous avons tiré l'impression que les épines nasales antérieure et postérieure sont des zones relativement fixes par rapport à la jointure prémaxillopalatine

Etude télécrânienne des mouvements cervicaux et palatins au cours de la croissance

The sagittal and anterior position of the hyoid bone is at the origin of the changes in orientation of the palatine laminae. A posterior-anterior movement of this bone allows the tongue to liberate the posterior part of the oral cavity; the palatine laminae rotate forwards and downwards. The opposite case is verified in the same way; the naso-palatine canal is a very malleable area, allowing a lowering of the anterior part of the palatine laminae. The vertical variations of the hyoid bone have little effect on the palate.La position sagittale de l’os hyoïde est à l’origine des modifications d’orientation des lames palatines. Ceci a été montré à partir de télécrânes sagittaux. Un mouvement postéro-antérieur de cet os permet à la langue de libérer la partie postérieure de la cavité buccale: les lames palatines font une rotation vers le bas et l’avant. Le contraire se vérifie de la même façon. Le canal naso-palatin est une zone très plastique; il permet un abaissement de la partie antérieure de la lame palatine. Les variations verticales hyoïdiennes influencent peu le palais

Premières molaires permanentes et variations palatine ou mandibulaire

101 children, each of them with two teleradiographies, were selected. The first X-ray was taken at the time of the mixed dentition, the second one, when the permanent dentition was established. The purpose of the research is to show the oscillations of the palatine and mandibular planes, and their link to the movements of the first permanent molars. The palatine plane is found to swing between - 7° and +5°, with an average of -0.97°. The posterior part of that plane rocks downwards in 51% of the children. The limits are -7° and -1°, with an average of -3.2°. In 22%, the plane rocks upwards between +1° and +5° with an average of +3.1°. In 27% it moves parallel to itself. The posterior part of the mandibular plane varies between -6° and +5°, with an average of -1.1°. It rocks downwards in 48% of the cases, between -6° and -1° with an average of -3.9°. In 22% of the children, this plane rocks upwards between +1° and +5°with an average of +2.5°. In 30%, it moves parallel to itself. The overall result is that the more the posterior part of the palate, or of the mandibule moves downwards, the more the first permanent molars get straight or move forwards.Le but de ce travail est de déterminer les oscillations des plans palatin et mandibulaire ainsi que leur lien avec les mouvements des premières monophysaires. Les téléradiographies, prises à quelques années d’intervalle, de 101 enfants, sont superposés sur le compas ptérygo-clivien. Plus la partie postérieure des lames palatines ou de la mandibule s’abaisse, plus les premières molaires se redressent ou se déplacent vers l’avant

Le trièdre ptérygo-clivien: reconstruction en 3D, stabilité ou variations possibles au cours de la croissance

The growth’s study, from skull’s radiographics, needs the use of superposition’s structures. Three X ray radiographics pictures from the front, from profile and from under are retalling by a soft. This orthogonazilation’s step has been realized for every child at two different ages. The reconstruction of the «clivus» straight and «pterygoïde» straights from three views gives the « pterygo-clivus triedre» which stability is studied for time.L’étude de la croissance, à partir de télécrânes, nécessite l’emploi de structures de superposition. Trois clichés radiographiques rayons X de face, de profil, en incidence axiale, ont été orthogonalisés par un logiciel. Cette étape a été réalisée pour chaque enfant à deux âges différents. La reconstruction de la droite clivienne et des droites ptérygoïdiennes sur les trois vues forme le trièdre ptérygo-clivien dont nous étudions la stabilité dans le temps

La symphyse mandibulaire. Ses variations transversales au cours de la croissance

The statistical study on transversal variations of fifty children’s symphysae seams to show that symphysae tends to become in harmony with mandible nervous courses, mandible corpus axis and condyle axis.L’étude statistique des variations transversales de la symphyse mentonnière sur cinquante enfants ayant été traités, semble montrer que la symphyse a tendance à s’harmoniser avec les trajets nerveux mandibulaires, l’axe des corpus mandibulaires et l’axe des condyles

Méthode d'orthogonalisation de clichés radio X par traitement d'images autorisant la reconstruction 3D d'éléments de la tête

In order to known better the unrolling of the growth, we dispode several radiographies elements which is sometimes difficult to connect with themselves.Using the computer, may give us the solution to this problem. We describe here a soft which authorizes the 3D reconstruction dating from X-ray radiographic pictures. During step called orthogonalization, the three pictures from the front, from profile and from under, are retalling by the soft. When it’s realized, any visible point from two views will automatically be visible in the third view.Pour mieux connaître le déroulement de la croissance, nous pouvons disposer de plusieurs éléments radiographiques qu’il est parfois difficile de relier entre eux.La réponse à ce problème peut être apportée par l’utilisation de moyens informatiques. Nous décrivons ici un logiciel qui autorise la reconstruction en 3D à partir de clichés radiographiques rayons X. Les trois clichés de face, de profil, et de dessous sont recadrés par le logiciel dans une étape dite «d’orthogonalisation». Une fois celle-ci réalisée, n’importe quel point visible sur deux vues sera automatiquement visible sur la troisième