Duffo G, Barreiro M, Olmedo D, Crosa M, Guglielmotti M B, Cabrini R L
Materials and Radiobiology Departments, National Atomic Energy Commission, Dental Materials and Oral Pathology Departments, Faculty of Dentistry, University of Buenos Aires, Argentina.
Acta Odontol Latinoam. 1999;12(1):3-10.
Corrosion phenomena would appear to play a decisive role in metallic implant long term behaviour. This study presents a method to correlate results obtained in "in vivo" and "in vitro" studies on materials used for metallic implants. Samples of titanium and copper immersed in saline solution (pH 7.4 and 5.2) were used for the "in vitro" study. Implants of these same materials were placed in rat tibiae following the method previously described by Cabrini et al. The animals were killed 14 days post-implantation, the tibiae were resected, radiographed and embedded in acrylic resin. Polarization curves revealed high corrosion in copper implants and low corrosion in titanium implants. It is important to point out that the titanium samples suffered slightly higher corrosion when immersed in a lower pH medium (pH 5.2), as in chronic inflammatory processes. A passive film was found on titanium samples as opposed to the strong corrosion observed in the copper implants. Microscopy revealed osseointegration around titanium implants and a severe inflammatory reaction with abscesses surrounding the copper implants. The method presented herein would allow to correlate "in vivo" and "in vitro" studies on corrosion in different implant materials and establish their relation with cell response.
腐蚀现象似乎在金属植入物的长期性能中起着决定性作用。本研究提出了一种方法，用于关联在金属植入物所用材料的“体内”和“体外”研究中获得的结果。将钛和铜样品浸入盐溶液（pH 7.4和5.2）中用于“体外”研究。按照Cabrini等人先前描述的方法，将这些相同材料的植入物植入大鼠胫骨中。植入后14天处死动物，切除胫骨，进行放射照相并嵌入丙烯酸树脂中。极化曲线显示铜植入物中的腐蚀程度高，而钛植入物中的腐蚀程度低。需要指出的是，与慢性炎症过程中一样，当钛样品浸入较低pH值的介质（pH 5.2）中时，其腐蚀程度会略高一些。与在铜植入物中观察到的强烈腐蚀相反，在钛样品上发现了一层钝化膜。显微镜检查显示钛植入物周围存在骨整合，而铜植入物周围有严重的炎症反应并伴有脓肿。本文提出的方法将能够关联不同植入材料腐蚀的“体内”和“体外”研究，并确定它们与细胞反应的关系。
