The aims were to investigate whether the use of platelet-rich fibrin membranes (PRF) for socket filling could improve microarchitecture and intrinsic bone tissue quality of the alveolar bone after premolar extraction and to assess the influence of the surgical procedure before implant placement. Twenty-three patients requiring premolar extraction followed by implant placement were randomized to three groups: (1) simple extraction and socket filling with PRF, (2) extraction with mucosal flap and socket filling with PRF, and (3) controls with simple extraction without socket filling. Implant placement was performed at week 8, and a bone biopsy was obtained for histomorphometric analysis. Analysis by microcomputed tomography showed better bone healing with improvement of the microarchitecture (P < 0.05) in group 1. This treatment had also a significant effect (P < 0.05) on intrinsic bone tissue quality and preservation of the alveolar width. An invasive surgical procedure with a mucosal flap appeared to completely neutralize the advantages of the PRF. These results support the use of a minimally traumatic procedure for tooth extraction and socket filling with PRF to achieve preservation of hard tissue.

Dental implants are commonly used in daily practice; however, most surgeons do not really know the characteristics of these biomedical devices they are placing in their patients. The objective of this work is to describe the chemical and morphological characteristics of 14 implant surfaces available on the market and to establish a simple and clear identification (ID) card for all of them, following the classification procedure developed in the Dohan Ehrenfest et al (2010) Codification (DEC) system. Fourteen implant surfaces were characterized: TiUnite (Nobel Biocare), Ospol (Ospol), Kohno HRPS (Sweden & Martina), Osseospeed (AstraTech), Ankylos (Dentsply Friadent), MTX (Zimmer), Promote (Camlog), BTI Interna (Biotechnology Institute), EVL Plus (SERF), Twinkon Ref (Tekka), Ossean (Intra-Lock), NanoTite (Biomet 3I), SLActive (ITI Straumann), Integra-CP/NanoTite (Bicon). Three samples of each implant were analyzed. Superficial chemical composition was analyzed using X-ray photoelectron spectroscopy/electron spectroscopy for chemical analysis, and the 100 nm in-depth profile was established using Auger electron spectroscopy. The microtopography was quantified using light interferometry. The general morphology and nanotopography were evaluated using a field emission-scanning electron microscope. Finally, the characterization code of each surface was established using the DEC system, and the main characteristics of each surface were summarized in a reader-friendly ID card. From a chemical standpoint, of the 14 different surfaces, 10 were based on a commercially pure titanium (grade 2 or 4), 3 on a titanium-aluminum alloy (grade 5 titanium), and one on a calcium phosphate core. Nine surfaces presented different forms of chemical impregnation or discontinuous coating of the titanium core, and 3 surfaces were covered with residual aluminablasting particles. Twelve surfaces presented different degrees of inorganic pollutions, and 2 presented a severe organic pollution overcoat. Only 2 surfaces presented no pollution (Osseospeed and Ossean). From a morphological standpoint, 2 surfaces were microporous (anodization) and 12 were microrough, with different microtopographical aspects and values. Ten surfaces were smooth on the nanoscale, and therefore presented no significant and repetitive nanostructures. Four implants were nanomodified: 2 implants were nanorough (Osseospeed and Ossean), and 2 were covered with nanoparticles (NanoTite and SLActive). TiUnite and Kohno HRPS were covered with extended cracks all over the surface. Only 8 surfaces could be considered homogeneous. This systematic approach allowed the main characteristics of these commercially available products to be gathered in a single ID card. It can be used as an experimental tool or a method for controlling industrial implant productions. The DEC system could be an interesting basis for the development of a clear and simple ISO standard for dental implant surfaces and other implantable devices.