Biomaterials and osteoradionecrosis of the jaw: Review of the literature according to the SWiM methodology.

OBJECTIVES: To systematically present and interpret the current literature on research and treatment perspectives for mandibular osteoradionecrosis (mORN) in the field of biomaterials. MATERIAL AND METHODS: A systematic review of the literature using the "Synthesis without meta-analysis" (SWiM) methodology was performed on PubMed, Embase and Cochrane, focusing on the implantation of synthetic biomaterials for bone reconstruction in mORN in humans and/or animal models. The primary endpoints were the composition, efficacy on mORN and tolerance of the implanted synthetic biomaterials. RESULTS: Forty-seven references were obtained and evaluated in full-text by two assessors. Ten (8 in humans and 2 in animal models) met the eligibility criteria and were included for analysis. Materials most often comprised support plates or metal mesh (5 of 10 cases) in combination with grafts or synthetic materials (phosphocalcic ceramics, glutaraldehyde). Other ceramic/polymer composites were also implanted. In half of the selected reports, active compounds (molecules, growth factors, lysates) and/or cells were associated with the reconstruction material. The number of articles referring to implantation of biomaterials for the treatment of mORN was small, and the properties of the implanted biomaterials were generally poorly described, thus limiting a thorough understanding of their role. CONCLUSION: In preventing the morbidity associated with some reconstructive surgeries, basic research has benefitted from recent advances in tissue engineering and biomaterials to repair limited bone loss.

[Acquired autoimmune haemophilia: Where is the place of rituximab in the treatment strategy? Reflection from a monocentric series of 8 patients and literature review]. / Hémophilie acquise auto-immune : quelle est la place du rituximab dans la stratégie thérapeutique ? Réflexion à partir d'une série monocentrique de 8 patients et revue de la littérature.

INTRODUCTION: Autoimmune acquired haemophilia is a rare autoimmune disease. The purpose of immunosuppressive therapy is to stop the production of autoantibodies that inhibit clotting factors VIII or IX. A corticosteroids-cyclophosphamide combination is recommanded as first-line therapy. From our experience at the University Hospital of Nîmes, we discuss the place of rituximab in the therapeutic arsenal. METHODS: We report a monocentric observational retrospective study. Our data are discussed in light of literature data, in particular cohorts EACH2 and SACHA. RESULTS: Eight patients (7 with FVIII anibodies) were consecutively included from 2005. The average age was 68.5 years with a male predominance (62.5%). Bleeding manifestations were usually spontaneous and superficial. A pathology, mostly autoimmune or neoplastic, was associated in 5/8 patients. A "by-pass" haemostatic treatment was prescribed for 3/8 patients. Rituximab was prescribed for 5/8 patients, three times as first-line therapy, and always associated with corticosteroids. Three patients received a cyclophosphamid/cortisone combination, two were treated exclusively with oral corticosteroids. Remission was obtained in all patients, without subsequent relapse. The average time to obtain remission under rituximab (after the first injection) was 32.5 days (10-143). The results observed in our series of patients are consistent with the data from the literature. CONCLUSIONS: Rituximab appears to be an effective and well-tolerated treatment for autoimmune acquired haemophilia. However, its place remains to be specified.

[Severe Mast Cell Activation Syndrome in a 15-year-old patient with an hypermobile Ehlers-Danlos syndrome]. / Le cas clinique du mois. Syndrome d'Activation Mastocytaire sévère chez un patient de 15 ans présentant un syndrome d'Ehlers-Danlos de type hypermobile.

We report the history of a 15-year old patient with a hypermobile Ehlers-Danlos syndrome (hEDS) (his mother, his two brothers and his sister have the same phenotype as him). He suffers mainly from a severe mast cell activation syndrome (MCAS) with an overreaction of the skin to any kind of contact (water of the shower, clothes, bed sheets) but he has also fatigue, headaches, and rash. This impressive rash is exacerbated after the shower and he has the urge to rest («shower's sign¼). We describe the MCAS and its easy, fast and very effective medication management, without any significant side effects as well as its frequent association with the hEDS. We finally introduce the original term of «MASED¼ to this MCAS, associated, linked or entangled to hEDS.

Nous présentons le cas d'un jeune patient âgé de 15 ans atteint d'un syndrome d'Ehlers-Danlos (SED) de type hypermobile (sa mère, ses deux frères et sa soeur présentent le même phénotype que lui). Il présente principalement un syndrome d'activation mastocytaire (SAMA) sévère avec une atteinte démesurée au niveau de la peau exposée au simple contact (avec l'eau, les draps, les vêtements), mais également de la fatigue, des céphalées ainsi que des éruptions qui sont exacerbées après la douche avec l'envie impérieuse de se reposer (le «signe de la douche¼). Nous décrivons le SAMA, sa prise en charge médicamenteuse simple, rapide et efficace et dépourvue d'effets secondaires notables ainsi que son association fréquente au SED. Nous introduisons finalement le terme original de «SAMED¼ à ce SAMA associé, lié ou intriqué au SED.

Combinatorial MAPLE deposition of antimicrobial orthopedic maps fabricated from chitosan and biomimetic apatite powders.

Chitosan/biomimetic apatite thin films were grown in mild conditions of temperature and pressure by Combinatorial Matrix-Assisted Pulsed Laser Evaporation on Ti, Si or glass substrates. Compositional gradients were obtained by simultaneous laser vaporization of the two distinct material targets. A KrF* excimer (λ=248nm, τFWHM=25ns) laser source was used in all experiments. The nature and surface composition of deposited materials and the spatial distribution of constituents were studied by SEM, EDS, AFM, GIXRD, FTIR, micro-Raman, and XPS. The antimicrobial efficiency of the chitosan/biomimetic apatite layers against Staphylococcus aureus and Escherichia coli strains was interrogated by viable cell count assay. The obtained thin films were XRD amorphous and exhibited a morphology characteristic to the laser deposited structures composed of nanometric round shaped grains. The surface roughness has progressively increased with chitosan concentration. FTIR, EDS and XPS analyses indicated that the composition of the BmAp-CHT C-MAPLE composite films gradually modified from pure apatite to chitosan. The bioevaluation tests indicated that S. aureus biofilm is more susceptible to the action of chitosan-rich areas of the films, whilst the E. coli biofilm proved more sensible to areas containing less chitosan. The best compromise should therefore go, in our opinion, to zones with intermediate-to-high chitosan concentration which can assure a large spectrum of antimicrobial protection concomitantly with a significant enhancement of osseointegration, favored by the presence of biomimetic hydroxyapatite.

A comparative physico-chemical study of chlorapatite and hydroxyapatite: from powders to plasma sprayed thin coatings.

Due to their bioactivity and osteoconductivity, hydroxyapatite (HA) plasma sprayed coatings have been widely developed for orthopedic uses. However, the thermodynamic instability of HA leads frequently to a mixture of phases which limit the functional durability of the coating. This study investigates the plasma spraying of chlorapatite (ClA) powder, known to melt without decomposition, onto pure titanium substrates using a low energy plasma spray system (LEPS). Pure ClA powder was prepared by a solid gas reaction at 950 °C and thermogravimetric analysis showed the good thermal stability of ClA powder in the range 30-1400 °C compared to that of the HA powder. Characterization of ClA coating showed that ClA had a very high crystalline ratio and no other crystalline phase was detected in the coating. HA and ClA coatings composition, microstructure and in vitro bioactivity potential were studied, compared and discussed. In vitro SBF test on HA and ClA coatings revealed the formation of a poorly crystalline apatite on the coating surface suggesting that we could expect a good osteoconductivity especially for the ClA coating prepared by the LEPS system.