On the Biotribological Surfaces of Dental Implants: investigation in the Framework of Osseointegration

In the last decades, the use of dental implants has been growing exponentially, but some clinical issues such as inflammations, infections or mechanical complications like fractures or implant loosening, are still open, leading to a failure and implants' revision surgery. Many researchers state that one of the main reasons is certainly due to a not complete or stable implant osseointegration respect the surrounding bone. As stated in literature the formation and the growth of the bone in contact with the implant is strictly correlated with the micro topography of the implant contact surfaces, because of the biotribological, biological and chemical interactions occurring on the surface. To date, however, only arithmetical roughness is reported in the most part of investigations as a valid surfaces' topographical parameter which could be correlated with osseointegration. Moreover, a consolidated and standardized procedure for dental implant surface measurements is not established. Hence, the aim of this investigation was to propose an advanced methodology for analyzing dental implant surfaces based on optical measurements and accurate data processing, and to discuss the results obtained on a real implant, in the framework of osseointegration and biotribological contact literature findings. With reference to a commercial dental implant, the topography was accurately achieved by an optical confocal and interferometric apparatus and then post processed to obtain all the quantities necessary for the contact surface accurate description dis- cussing the role of the topographical quantities on the influence of bone/implant contact/osseointegration phenomena. Height, spatial, hybrid and functional parameters were presented for both waviness and roughness profiles providing significant discrepancies in most of the roughness values. On the other hand, the additional specific investigations such as surface isotropy or particle analysis may yield the basis for a novel protocol of surfaces topographical characterization procedure in dentistry.