[en] Dental implants have emerged as the preferred choice for tooth replacement, reaching about one million implantations per year. Among factors affecting dental implant success, surface topography has been recognised as an important parameter since it is known to affect the cellular response and, ultimately, osseointegration. Although it has generally been overlooked, the topography integrity may be jeopardised due to the stresses to which implant surfaces are subjected during surgical insertion. The study of this phenomenon is of great importance because the surface topography alteration may lead to a cellular response that differs from the ones analysed in in vitro assays, as well as to titanium particle release, which has been related to increased bone resorption, peri-implantitits and implant failure. The main goal of the present dissertation was to analyse and predict the topographic alteration of endosseous dental implants generated during the surgical insertion. In light of the lack of standardisation regarding dental implant topographic characterisation, the effect of the data acquisition and processing variables on the 3D topographical parameters was first evaluated. Then, based on the results obtained, a generalized topographical characterization strategy for endosseous dental implant was established. Aimed at elucidating the effect of the insertion forces on the topography of implants, commercial dental implants were inserted into cow rib bones using standard surgical procedures. 3D topographical characterisation techniques were employed to quantify the modification and to approximate the material loss. Post-inserted implants showed wear and plastic deformation of the most prominent peaks, and released titanium particles were observed in the bone site underlying the implants. The obtained results suggest that the surface modification is a complex phenomenon conditioned by the combination of surface treatment, implant macrogeometry and surgical procedure. Additionally, an in vitro study was conducted to investigate whether the topographic alteration generated during dental implant insertion affects the cell response. Within the limits of the study, the experimental data rejected the hypothesis that osteoblast attachment and proliferation could be significantly affected by the topographical modification generated during dental implant insertion. Finally, the correlation between the surface modification and certain physically meaningful properties of surface topography was successfully established through the newly developed product of 3D topographical parameters named Si. This novel parameter is presented as a useful tool to predict whether a surface is more prone to suffer alterations during insertion, and may therefore contribute to foster advancements in the design of better performing endosseous implants.

[eu] Hortz inplanteak hortzak ordezkatzeko lehen aukera bilakatu dira, eta urtean milioi bat inguru inplante ezartzera iritsi dira. Hortz inplante arrakastatsu bat lortzeko erabakigarriak diren faktoreen artean, gainazalaren topografia parametro garrantzitsutzat jotzen da, jakina baita erantzun biologikoan eta, finean, osteointegrazioan eragina duela. Orokorrean aintzat hartu ez den arren, gainazalaren topografiaren osotasuna konprometitua egon daiteke intsertzio kirurgikoan sortzen diren esfortzuak direla eta. Fenomeno horren azterketa garrantzi handikoa da, topografiaren alterazioaren ondorioz erantzun zelularra in vitro saiakuntzetan aztertutakoaren ezberdina izan eta titanio partikulak askatu daitezkeelako, zeina hezurraren erresortzio, periinplantitis eta inplantearen porrotarekin lotu den. Tesi doktoral honen helburu nagusia, intsertzio kirurgikoan sorturiko hortz inplanteen gainazalaren topografiaren alterazioa aztertu eta aurreikusteko teknikak garatzea izan da. Hortz inplanteen karakterizazio topografikorako estandarizaziorik ez dagoela eta, lehenik eta behin datuak eskuratzen eta prozesatzen parte hartzen duten parametroek 3Dko parametro topografikoen balioetan duten eraginaren analisi bat egin da, eta, lorturiko emaitzetan oinarrituz, hortz inplanteen topografia karakterizatzeko estrategia bat garatu da. Intserzio kirurgikoaren esfortzuek hortz inplanteen gainazalean duten efektua aztertzeko helburuarekin, hortz inplante komertzialak behien saiheski hezurrean txertatu ziren prozedura kirurgiko estandarrak jarraituz, eta 3Dko karakterizazio teknikak erabili ziren modifikazioa kuantifikatu eta material galera kalkulatzeko. Txertatu ondoren, hortz inplanteek tontor garaienen desgastea eta deformazio plastikoa erakutsi zuten, eta titanio partikulak aurkitu ziren inplantea inguratzen duen hezurrean. Lorturiko emaitzek iradoki zuten hortz inplanteen modifikazioa fenomeno konplexua dela, gainazalaren tratamendu, inplantearen makro-geometri eta prozesu kirurgikoarekiko duen menpekotasunaren ondorioz. Are gehiago, in vitro analisi bat burutu zen ea intsertzioan zehar sorturiko alterazio topografikoek erantzun zelularrean efekturik duen ikertzeko. Ikerketaren mugak kontuan izanik, datu esperimentalek baztertu egin zuten modifikazio topografikoak osteoblastoen ugalketan eta adhesioan efektua dutelako hipotesia. Azkenik, gainazalaren modifikazioaren eta propietate topografikoen arteko korrelazioa arrakastarekin ezarri zen, garatutako 3Dko parametro topografikoen produktu berri baten bitartez. Si izena eman zaion parametro berri horri esker, gainazal batek alterazioak jasateko duen joera aurreikusi daiteke, eta beraz, hortz inplante funtzionalagoen diseinuan aurrerapenak sustatzeko erreminta egokitzat aurkezten da.