implants - international magazine of oral implantology International Edition

I industry report Fig. 1_Implant tested – D. Fig. 2_Reference implant – B. Fig. 3_Drilling of implant wells. Fig. 4_Positioning of the implants on the maxilla. Fig. 5_Implants in place. Fig. 6_Periimplant bone organisation. _Introduction Nowadays, numerous studies attempttoshowtheimportance of implant surface treatment1 for accelerating the osseointe- grationprocess.2 Surfacefinish- ing, notably roughness genera- tion, has allowed to increase the abilityoftitaniumtolinkdirectly to bone without any intermedi- ary fibrous tissue.3 Thus, it seems that if the osteoblast response is obviously measured by histology, it does not inform on long-term implant success but only on the cell organisation of the peri- implantbonetissueanditprovidesnoinformationon the architecture of this tissue.4 Only the study of newly-formedtrabecularbonetissuearoundtheim- plant can provide predictive results concerning im- plant durability. Trabecular tissue forms only 20 per cent of the skeletal mass but 80 per cent of the ex- change surface between bone and marrow. This mi- crostructure plays a mechanical role because it en- sures that the external loads be cor- rectly distributed in the bone vol- ume.Duetoitsmechanicalfunction, trabecular bone is a preferential site to study the spatial and geometrical propertiesofthisbonetissueandthe interactionbetweenmedicalappara- tus and bone tissue. The future of a dental implant after loading mainly depends on: trabecular organisation, intimacy of contact between metal structureandbone,surroundingbone volume, bone density.5 The aim of the present work was to characterise the periimplant bone organisation and to evaluatetheinfluenceofimplantshapeon osseointegration, using a porcine model. Implanta- tions were carried out on growing piglets on maxilla andtrabecula,becausetheexperimentalresultspub- lished up to now mostly concern fixtures set on tibia or iliac of pork or dog (results so obtained concern mainlycorticalboneandlesstrabecularbone).6 _Material and method 28 implant fixtures (diameter 3.5 mm, length 7mm)weresetinthejawbonesofeightpigs,16inthe mandibleand12inthemaxilla.Twotypesofimplant were used: implant B with a cylindrical body and im- plantDpresentingashrinkunderitsneckasshownin Figs.1and2.Histomorphometricanalysiswascarried out on samples taken 45 days after implantation. Sampleswereanalysedwitharesolutionof18µ. _Animal experiments Experiments were carried out on eight pigs of meanweightof12.1kgatday0and32.3kgwhensac- rificed.Initialdentureismixed,completeandhealthy for each animal. The project was presented to the ethiccomityofInstituteofExperimentalSurgery(ICE) of Centre Léon Bérard (Lyon, France). Animal choice andcare,andexperimentalprocedurewereapproved bythecommittee. Influence of implant design on osseointegration Authors_Dr R. Fromental, Dr S. Langonnet, S. Chesnay, Prof. J.C. Béra, Dr B. Lavandier, Dr A. Gleizal, Dr M. Paris, Dr R. Gourmet & Prof. M. Rivoire, France 32 I implants1_2014 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 2 Fig. 1