Development of professional recommendations on orthodontic retention: short version / Développement de recommandations professionnelles sur la contention en orthodontie : version courte

Introduction: Retention is the set of means, processes or devices that contribute to maintain the teeth in the position and the arches in the shape given by the treatment as long as possible. Given the heterogeneity of practices, devices used and follow-up modalities, the French Society of Dentofacial Orthopedics, a scientific society, has proposed Clinical Practice Guidelines (CPG) for orthodontic retention. This article presents the method used to develop the CPG full-text and the guidelines produced. Materials and Methods: A review of the literature was carried out after a bibliographic search of databases. The CPG full-text and guidelines were drafted, graded according to the level of evidence, then reread, discussed and validated by the experts of the workgroup. A second review by a group of external experts was then carried out before final validation of the CPG for publication. Results: Of 652 articles selected, 53 met the inclusion criteria and were used to prepare the CPG full-text to produce 41 grade C items and 23 expert agreements, constituting 40 guidelines. Discussion: There is still no consensus on the choice of materials. The literature remains poor on the functions. Some devices, more used in France, are poorly documented in the literature. Conclusion: The CPGs provide recommendations on the factors to consider before using a retainer, the effectiveness of the different devices, their failures and adverse effects, as well as the follow-up procedures.

Introduction: La contention est l'ensemble de moyens, de procédés ou de dispositifs contribuant à maintenir le plus longtemps possible les dents dans la position et les arcades dans la forme données, par le traitement. Compte tenu de l'hétérogénéité des pratiques, des dispositifs utilisés et des modalités de suivi, la Société Française d'Orthopédie Dento-Faciale, société savante, a proposé des recommandations de bonne pratique (RBP) sur la contention orthodontique. Cet article présente la méthode d'élaboration de l'argumentaire scientifique et les recommandations produites. Matériels et méthodes: Une revue de la littérature a été réalisée après recherche bibliographique dans les banques de données. Un argumentaire scientifique et des recommandations gradées en fonction du niveau de preuve ont été rédigés, puis relus, discutés et validés par les experts du groupe de travail. Une deuxième relecture par un groupe de lecture, composé d'experts externes, a ensuite été effectuée avant la validation finale des recommandations pour diffusion. Résultats: Sur 652 articles sélectionnés, 53 répondaient aux critères d'inclusion et ont permis de rédiger l'argumentaire scientifique pour en tirer 41 items de grade C et 23 accords d'expert constituant 40 RBP. Discussion: Le choix des matériaux ne fait pas encore consensus. La littérature reste pauvre sur les fonctions. Quelques dispositifs, davantage utilisés en France, sont peu documentés dans la littérature. Conclusion: Les RBP fournissent des recommandations sur les facteurs de choix préalables à la réalisation d'une contention, l'efficacité des différents dispositifs, les échecs et les effets indésirables de ceux-ci, ainsi que sur les modalités de suivi.

GlialCAM, an immunoglobulin-like cell adhesion molecule is expressed in glial cells of the central nervous system.

Using structure based genome mining targeting vascular endothelial and platelet derived growth factor immunoglobulin (Ig) like folds, we have identified a sequence corresponding to a single transmembrane protein with two Ig domains, which we cloned from a human brain cDNA library. The cDNA is identical to hepatocyte cell adhesion molecule (hepaCAM), which was originally described as a tumor suppressor gene in liver. Here, we show that the protein is predominantly expressed in the mouse and human nervous system. In liver, the expression is very low in humans, and is not detected in mice. To identify the central nervous system (CNS) regions and cell types expressing the protein, we performed a LacZ reporter gene assay on heterozygous mice in which one copy of the gene encoding the novel protein had been replaced with beta-galactosidase. beta-galactosidase expression was prominent in white matter tracts of the CNS. Furthermore, expression was detected in ependymal cells of the brain ventricular zones and the central canal of the spinal cord. Double labeling experiments showed expression mainly in CNPase positive oligodendrocytes (OL). Since the protein is predominantly expressed in the CNS glial cells, we named the molecule glial cell adhesion molecule (GlialCAM). A potential role for GlialCAM in myelination was supported by its up-regulation during postnatal mouse brain development, where it was concomitantly expressed with myelin basic protein (MBP). In addition, in vitro, GlialCAM was observed in various developmental stages of OL and in astrocytes in processes and at cell contact sites. In A2B5 positive OL, GlialCAM colocalizes with GAP43 in OL growth cone like structures. Overall, the data presented here indicate a potential function for GlialCAM in glial cell biology.

The envelope protein of a human endogenous retrovirus-W family activates innate immunity through CD14/TLR4 and promotes Th1-like responses.

Multiple sclerosis-associated retroviral element (MSRV) is a retroviral element, the sequence of which served to define the W family of human endogenous retroviruses. MSRV viral particles display proinflammatory activities both in vitro in human mononuclear cell cultures and in vivo in a humanized SCID mice model. To understand the molecular basis of such properties, we have investigated the inflammatory potential of the surface unit of the MSRV envelope protein (ENV-SU), the fraction that is poised to naturally interact with host cells. We report in this study that MSRV ENV-SU induces, in a specific manner, human monocytes to produce major proinflammatory cytokines through engagement of CD14 and TLR4, which are pattern recognition receptors of primary importance in innate immunity. ENV-SU could also trigger a maturation process in human dendritic cells. Finally, ENV-SU endowed dendritic cells with the capacity to support a Th1-like type of Th cell differentiation. The data are discussed in the context of immune responses and chronic proinflammatory disorders.

Correlation between disease severity and in vitro cytokine production mediated by MSRV (multiple sclerosis associated retroviral element) envelope protein in patients with multiple sclerosis.

MSRV is a retroviral element previously isolated in cell cultures from patients with multiple sclerosis. It is part of a new multi-copy endogenous retrovirus family named HERV-W and displays pro-inflammatory properties both in vitro in human PBMC cultures and in vivo in a humanized SCID mice model. In the present study, we have evaluated potential links between the pro-inflammatory properties of MSRV envelope protein and MS disease. Thus, cytokine productions mediated by the surface unit of MSRV envelope protein were evaluated in PBMC of MS patients and compared with healthy controls. Divergent reactivity to ENV-SU between MS and control PBMC was observed and was reflected by a significant increase of IFN-gamma, IL-6 and IL-12p40 production by the tested MS population. Interestingly, the overproduction of IL-6 and IL-12p40 was found to correlate with disease severity (EDSS) in most patients. Altogether our data suggest that MSRV envelope protein may induce an abnormal cytokine secretion, thus contributing to the inflammatory process in MS.

Increased blood myeloid dendritic cells and dendritic cell-poietins in Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH), previously known as histiocytosis X, is a reactive proliferative disease of unknown pathogenesis. Current therapies are based on nonspecific immunosuppression. Because multiple APCs, including Langerhans cells and macrophages, are involved in the lesion formation, we surmised that LCH is a disease of myeloid blood precursors. We found that lin(-) HLA-DR(+)CD11c-+ precursors of dendritic cells, able to give rise to either Langerhans cells or macrophages, are significantly (p = 0.004) increased in the blood of LCH patients. The analysis of serum cytokines in 24 patients demonstrated significantly elevated levels of hemopoietic cytokines such as fms-like tyrosine kinase ligand (FLT3-L, a dendritic cell-mobilizing factor, approximately 2-fold) and M-CSF ( approximately 4-fold). Higher levels of these cytokines correlated with patients having more extensive disease. Serum levels of FLT3-L and M-CSF were highest in high risk patients with extensive skin and/or multisystem involvement. Finally, patients with bone lesions had relatively higher levels of M-CSF and of stem cell factor. Thus, early hemopoietic cytokines such as FLT3-L, stem cell factor, and M-CSF maybe relevant in LCH pathogenesis and might be considered as novel therapeutic targets.