[Membranes in pre-implantation surgery]. / Les membranes en chirurgie pré-implantaire.

The use of membranes in pre-implantation surgery is part of the guided bone regeneration (GBR) concept, one of the usual bone augmentation techniques. Membranes for GBR procedures have two main uses: a mechanical function to maintain bone regeneration space and a physical function as cellular barrier. The goal is to promote colonization of the regeneration space located under the membrane, by osteogenic cells from the residual bone walls. GBR was the subject of numerous publications and protocols since its first use in the 1980s. These protocols are mainly supported by team experience and the level of evidence is poor. Few indications are truly validated. The goal of our study was to review the recent literature on membrane use for pre-implantations surgery, and, in the absence of any consensus, to provide some arguments for their rational use.

[Massive sinus-lift procedures with beta-tricalcium phosphate: long-term results]. / Greffes sinusiennes massives par phosphate tricalcique. Résultats à long terme.

INTRODUCTION: The use of bone substitutes in massive sinus-lift pre-implant procedures remains controversial. The aim of our study was to evaluate the long-term reliability of pure-phase beta-tricalcium phosphate (betaTCP, Cerasorb, Curasan, Kleinostheim, Germany) used in this particular indication. MATERIAL AND METHOD: Twenty patients (33sinus) presenting with severe sinus floor atrophy (class 4 to 6 according to Cawood) and having undergone a sinus lift procedure by mean of betaTCP were followed in a prospective study between January 2002 and May 2008. The surgical approach was classical (under local anesthesia in eight patients) and the sinuses were filled with betaTCP (6 cm3 on average per sinus) and autologous growth factors (platelet rich plasma PRP and platelet rich fibrin PRF, according to the technique described by Dohan and Weibrich). One hundred and twenty-three dental implants were inserted in the grafted sinuses between the fourth and the eighth postoperative month (Nobel Biocare MK III and MK IV-mean length: 12.44 mm) using a 2-step buried technique and loaded between the fourth and the sixth month. Follow-up included regular clinical examination and panoramic X-rays to screen for possible sinus and implant complications. The control X-rays also allowed measuring the biomaterial resorption rate. RESULTS: The mean postoperative follow-up was 4.5 years for the sinus lift procedures and 4 years for the implants. We noted one case of local infection at the 15th postoperative day (3%). The implant success rate was 97.6% (lack of osteo-integration for two implants in the same patient, one failure after loading). The prosthetic success rate was 100%. The mean resorption rate of the material was 20.3% and the mean gain of height was 16.9 mm. DISCUSSION: The use of betaTCP associated to growth factors (PRP ou PRF) without bone graft, in massive sinus-lift procedures induces few complications. The implant success rate is comparable to the one obtained by using autologous bone grafts. The resorption rate of the material is comparable to that of autologous bone.

A novel type of resistance plasmid in Haemophilus influenzae.

Resistance plasmids of a novel type were found in two Haemophilus influenzae clinical isolates. pPJ301 and pPJ302 are 10.0 kilobases in size, carry a Tn2-like transposable element, and are related only by their common beta-lactamase genes to the other two types of resistance plasmids known to occur in H. influenzae.