RESUMEN
Biofunctionalization was investigated for polymers and metals considering their scarce integration ability. On the contrary few studies dealt with ceramic biofunctionalization because the bioactive and bioresorbable surfaces of ceramics are able to positively interact with biological environment. In this study the cell-response improvement on biofunctionalized wollastonite and diopside-based scaffolds was demonstrated. The ceramics were first obtained by heat treatment of a silicone embedding reactive oxide fillers and then biofunctionalized with adhesive peptides mapped on vitronectin. The most promisingin vitroresults, in terms of h-osteoblast proliferation and bone-related gene expression, were reached anchoring selectively a peptide stable toward proteolytic degradation induced by serum-enriched medium. Inin vivoassays the anchoring of this protease-stable adhesive peptide was combined with self-assembling peptides, for increasing cell viability and angiogenesis. The results demonstrated external and internal cell colonization of biofunctionalized scaffolds with formation of new blood vessels (neoangiogenesis) and stimulation of ectopic mineralization.
Asunto(s)
Regeneración Ósea/efectos de los fármacos , Sustitutos de Huesos , Cerámica , Péptidos , Andamios del Tejido/química , Adulto , Animales , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cerámica/química , Cerámica/farmacología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Péptidos/química , Péptidos/farmacología , Ingeniería de Tejidos/métodosRESUMEN
Nickel is a constituent of many dental alloys. This paper reviews mainly papers published after 1985 with regards to biological reactions to nickel in dentistry. Nickel is an allergen, but there is no evidence that individual patients are at a significant risk of developing sensitivity solely due to contact with nickel-containing dental appliances and restorations. Hypersensitivity reactions to nickel are only likely to occur with prior sensitization from non-dental contacts and even these are rare. Clinical evidence has been presented to show that small doses of nickel, e.g. from dental appliances, may induce tolerance to this allergen. The papers reviewed report low rates of release of nickel from dental alloys. Some nickel compounds, which are mildly cytotoxic, have been implicated as carcinogens by inhalation in industrial settings, but these compounds are not present in dentistry-related operations, including dental technology procedures. Nickel-containing alloys and compounds have not been associated with increased cancer risk by oral or dermal routes of exposure. It is concluded that, subject to use according to established techniques, nickel-containing dental alloys do not pose a risk to patients or members of the dental team.
