History and current state of metal adhesion systems used in prosthesis fabrication and placement.

The adhesion techniques used in prosthetic dentistry have substantially improved with respect to retention of veneering resin to the metal framework of resin-veneered restorations and the bonding of resin-bonded fixed partial dentures (RBFPDs) to abutment teeth. In the early 1970s, prostheses relied on macromechanical retention for veneering surfaces and the retention holes of retainers. Later, retention was achieved by using small spherical particles. In addition, the use of small pits created by electrochemical corrosion was tested in resin-veneered restorations and RBFPDs. Thus, micromechanical retention gradually supplanted macromechanical retention. First-generation adhesive monomers were introduced at the end of the 1970s and were succeeded in the early 1980s by the marketing of adhesive resin cements, which were effective for use with non-noble alloys when surface oxidation procedures were used. In 1994, a second-generation adhesive primer for noble alloys was introduced, which prompted development of other adhesive primers. These primers were applied mainly to silver-palladium-copper-gold and type IV gold alloys and improved the reliability of RBFPDs. Recent studies have confirmed the effectiveness of such primers when used with high-gold-content metal ceramic alloys. Due to these developments, RBFPDs now have excellent esthetic characteristics.

[Publications related to dental materials in all the volumes of the journal Fogorvosi Szemle]. / Az anyagtannal összefüggô közlemények a Fogorvosi Szemle eddig megjelent évfolyamaiban.

Among all the publications of the hundred-years-old Fogorvosi Szemle, there are only a few that deal with dental materials relative to other areas of dentistry. However, even this small number of articles reveals the change and advancement of dental materials and technologies.

The high-copper dental amalgam alloys.

For many years, the amalgamation of silver with mercury to produce a condensable mixture which could be used to restore carious defects in teeth followed a tortuous path of negative results. However, at the turn of the century, amalgam alloys having acceptable characteristics for successful clinical use emerged. From that point on, silver amalgam was widely accepted as the material of choice for low-cost, easily placed, and durable restorations. About 60 years later, a major discovery occurred that resulted in a most significant improvement in the clinical performance of this material. The key to this improvement was an increase in the Cu content of the amalgam alloy which previously had been considered to be inappropriate. This paper describes the history of this discovery, which produced what has come to be known as high-copper dental amalgam alloys.

Reflections on my involvement in orthodontic research.

Some years ago, Professor Takihashi, who was then the greatest living professor of orthodontics in Japan, called on us in Ann Arbor just before his retirement. I asked Dr. Takihashi who would replace him? and he replied, "There's a young man who will do better than I because he will be able to take Japanese orthodontics to the world and bring the world's orthodontics to Japan." That young man was Fujio Miura. Fujio Miura has, in the years since Takihashi spoke to me, written one of the most amazing records in the history of our specialty. His research is as far ranging as anyone's. For example, in biology he has written well on the ethnology of Japanese craniofacial morphology and that of the aborigines in Japan. He has written on developmental biology and on the tissue reaction of tooth movements. In metallurgy he has contrived alloys that have revolutionized our appliances, for he was a pioneer in the use of nickel-titanium wires. Fujio Miura invented direct bonding. Professor Miura has fulfilled Professor Takihashi's predictions well for he has become the most famous orthodontic professor in Japan's history. It is interesting to see that his students occupy most of the chairs of orthodontics in Japan and many elsewhere. Miura is an accomplished artist who has exhibited his work. This personable scholar probably attends more meetings of the American Association of Orthodontists Society than most American members, and he is equally at home in the European society, and many other orthodontic groups in the world.

Contribuiçäo para a avaliaçäo da biocompatibilidade de ligas de cromo-níquel pelo estudo histomorfológico das reaçöes teciduais em conjuntivo de ratos / Contribution to the evaluation of chromium-nickel containing dental alloys by histomorphological study of reaction in connective tissues of rats

A finalidade de nosso trabalho experimental foi a avaliaçäo histológica das reaçöes teciduais que 3 ligas metálicas de cromo-níquel pudessem causar no tecido conjuntivo de ratos, bem como sugerir uma regiäo alternativa para a implantaçäo dos corpos-de-prova. A avaliaçäo microscópica mostrou, na grande maioria dos casos, encapsulamento dos implantes e escasso infiltrado inflamatório. Em alguns casos verificamos ora pequena quantidade de pigmento finamente granular, ora a formaçäo de grumos grosseiros, e até algumas estruturas de aspecto cristalino e coloraçäo esverdeada. Em apenas 1 dos casos verificamos um espessamento da cápsula devido à intensa reaçäo inflamatória crônica do tipo granuloma por corpo estranho. Estes fatos nos levaram a concluir que as 3 ligas ensaiadas apresentaram resultados variáveis. Com relaçäo à regiäo escolhida para a localizaçäo dos implantes, esta mostrou-se satisfatória, tanto pelo acesso quanto pela facilidade de localizaçäo quando da remoçäo dos corpos-de-prova