Diffusion model to describe osteogenesis within a porous titanium scaffold.

In this study, we develop a two-dimensional finite element model, which is derived from an animal experiment and allows simulating osteogenesis within a porous titanium scaffold implanted in ewe's hemi-mandible during 12 weeks. The cell activity is described through diffusion equations and regulated by the stress state of the structure. We compare our model to (i) histological observations and (ii) experimental data obtained from a mechanical test done on sacrificed animal. We show that our mechano-biological approach provides consistent numerical results and constitutes a useful tool to predict osteogenesis pattern

In vivo study of human mandibular distraction osteogenesis. P. 2, Determination of callus mechanical properties

Distraction Osteogenesis (DO) is a surgical technique used to reconstruct bone defects. To improve the current treatment protocols, the knowledge of the mechanical properties of the bone regenerate is of major interest. The aim of this study, constituting the second part of our paper previously published in Acta of Bioengineering and Biomechanics, was to identify the elastic and viscous properties of bone callus. This is done in the case of a mandibular DO by analyzing the experimental measurements of the forces imposed on bone regenerate by a distraction device. The bone transport forces were evaluated thanks to strain gauges glued on the distraction device. A rheological model describing the callus constitutive behavior was developed and the material constants involved were identified. The time-dependent character of the bone regenerate mechanical behavior was confirmed. The viscous response of the mesenchymal tissue was described by two characteristic times. The first one describing the viscoelastic callus behavior was estimated to be 140 seconds and the second one representing the permanent bone callus lengthening was evaluated to be 5646 seconds. An average value of 0.35 MPa for the regenerate Young’s modulus was deduced. The elastic properties of mesenchymal tissue found are in agreement with the rare data available in the literature

La dimension psychique dans les protocoles chirurgico-orthodontiques

Si de nombreuses études ont évalué les corrélations entre profil psychologique et insatisfaction post-opératoire, aucune n’a cherché à étudier en quoi la demande initiale pouvait être le vecteur majeur de l’insatisfaction post-opératoire. Les résultats d’une étude exploratoire ont permis de dégager la spécificité de la demande de protocole chirurgico-orthodontique. Nous proposons la mise en place d’un protocole de recherche observationnel et prospectif : 100 patients inclus seront suivis de manière longitudinale sur trois ans (temps moyen entre la première consultation et six mois en post-opératoire). La durée totale de l’étude est de quatre ans et se découpe en trois temps : proposition de traitement, HDJ pré- opératoire, HDJ post-opératoire (trois entretiens psychologiques après l’administration d’un questionnaire clinique, de l’échelle d’affirmation de soi de Rathus, de l’échelle de dépression et d’anxiété d’Hamilton et de l’échelle de qualité de vie SF-36). L’objectif principal de la recherche est d’étudier la corrélation entre la demande initiale et le degré de satisfaction. Les objectifs secondaires sont l’évaluation de l’évolution des scores d’estime de soi, d’anxiété et de dépression, et de qualité de vie aux trois temps de la recherche; l’impact du suivi psychologique sur cette évolution; la mise en place d’un questionnaire portant sur la demande initiale susceptible d’orienter le praticien sur l’adéquation du traitement

Psychological aspects of ortho-surgical protocols

By the results of an exploratory research, we were able to put forward the specificity of the request in ortho-surgical protocol. Even if many studies evaluated correlations between psychological profiles and postoperative dissatisfaction, no one asked for the link between initial request and postoperative dissatisfaction. We suggest setting up an observation and forwardlooking research’s protocol: 100 patients must been followed in a longitudinal way during 3 years (medium time between the first consultation and 6 months after the surgery). The whole duration of the study is about 4 years. It’s divided in three times: treatment’s proposal, preoperative hospitalization’s day, postoperative hospitalization’s day (three psychological interviews after the auto-administration of a clinical questionnaire, the Rathus Scale, the Hamilton depression and anxiety scale and the SF-36 quality of life scale. The research’s main objective is to study the correlation between initial request and the satisfaction level. The second objectives are the evaluation of self-respect, anxiety, depression, and quality of life scales at the three times of the research, and the evaluation of the psychological following’s impact on the results. Thirdly, we want to set up a questionnaire upon the initial request to help the practitioners

The multidisciplinary approach to orthodontic–surgical protocols in the Maxillofacial Department of Pitié-Salpêtrière Hospital

The creation of a multidisciplinary consultation in the maxillofacial service of the Pitié-Salpêtrière – Charles-Foix hospital, improved the efficiency of patient care. They don’t only see a maxillofacial surgeon and an orthondontist, they also have a follow up by an psychologist, a physiologist and a nutritionist. Preoperating day is the focal point of the patient care: it’s the link between the preoperative time and the operative time

L’approche pluridisciplinaire des protocoles chirurgico-orthodontiques du service de chirurgie maxillo-faciale de l’hôpital Pitié-Salpêtrière

La mise en place d’une consultation pluridisciplinaire orthodontico-chirurgicale, dans le service de chirurgie maxillo-faciale du groupe hospitalier Pitié-Salpêtrière – Charles-Foix, a permis d’améliorer la prise en charge des patients. Ils ne sont plus vus seulement par un orthodontiste et un chirurgien, ils sont également suivis sur le plan psychique, physiologique et nutritionnel. La journée pré-opératoire est l’élément central de la prise en charge; elle permet de faire le lien entre le temps préopératoire et le temps opératoire