RESUMO
OBJECTIVES: The main purpose of this work was to assess the short-term bone regenerative potential of new osteoconductive implants. The novelty of the study lies in the analysis of the effectiveness of a novel two-step treatment which combines shot-blasting with a thermo-chemical treatment, at very short times after implant placement in a minipig model. MATERIALS AND METHODS: Three hundred twenty implants with four different surface treatments, namely bioactivated surfaces, micro-rough grit-blasted, micro-rough acid-etched and smooth as-machined titanium implants were placed into the bone of 20 minipigs. The percent of bone-to-implant contact was determined 3 days, 1, 2, 3 and 10 weeks after implant placement by histomorphometric analysis. Surface composition, topography and wettability of the implant specimens were analysed. RESULTS: The combination of shot-blasting and thermo-chemical treatment accelerated bone regeneration at early stages in comparison with all other treatments between day 3 and week 3 (p < 0.05). The value of osseointegration attained at week 2 was maintained until the end of the experiment without any significant changes (percent direct contact ≈ 85 %). This was mostly attributed to the ability of these implants to form in vivo a layer of apatitic mineral that coated the implant and could rapidly stimulate bone nucleation and growth from the implant surface. CONCLUSIONS: The surface quality resulting from this treatment on cpTi provided dental implants with a unique ability of rapid bone regeneration and osseointegration. CLINICAL RELEVANCE: This treatment represents a step forward in the direction of reducing the time prior to implant loading.