Int..I. DeL Hiu1.39: 13-23(1995) 13 The tooth as a model in organogenesis An interview with Professor Harold C. Slavkin Organogenesis is a complex process in which, as a result of several instructive and permissive cell-cell interactions, there ap- pear new cell strains, precise modifications of the extracellular matrix, morphological and topographical changes and new tissue functions. This set of alterations occurs within a specific sequence in which regional alterations take place one after anolher until, finally, well defined organs emerge wholly integrated into the general physiology of the organism they are part of. The secondary induction mechanism within developing organs is usually analyzed through the study of experimental models from which general hypotheses applicable to most tissue complexes may be inferred. Tooth is undoubtedly one of the most complete, and most useful, of such models. The ease with which it lends itself to experimental study, to in vitro cultivation and cytological and molecular analysis, together with the precise delimitation of its presumptive territories (dental papilla and dental lamina), the morphological characteristics of its typical cells (odontoblasts and adamantoblasts), the spectacular changes in its extracellular ma- trix and subsequent secretion ot products (predentine/dentine and enamel), and its patterns of mineralization and regional differences (e.g. between incisors, moiars, etc.) - all these things make tooth a unique model with extraordinary appeal for developmental biolo- gists and obvious medical significance. For decades now, a number of outstanding scientists have explored the advantages of tooth as a model for the experimental study of organogenesis by applying a wide range and variety of techniques, mainly in the fields of cell and molecular biology. Since among these investigators one of the most distinguished over fhe past twenty-five years has been Professor Harold Slavkin, we felt that a good way of introducing the subject would be to review the enormous scientific progress achieved in this field through an analysis of his highly enlightening career. --- JUAN ARECHAGA* Department of Cell Biology, Univesity of the Basque Countrty, Leioa, Spain Harold Slavkin was born in 1938 in Chicago, Illinois, the first son of a Russian couple who in the previous decade had emigrated from the Soviet Union. His parents - his father was a pharmacist. his mother a nurse - were very young when they arrived in the United States with their respective families and adapted to their new homeland with all the enthusiasm and tenacity of pioneers. At the same time they managed to imbue their own children with what they saw as the new, specifically American values, while also providing them with a European cultural background. This mixture of Old and New World qualities made a profound impression on the young Harold Slavkin: "my parents shared beliefs that anything was possible and that the art of criticism was a valuable part of living: they ioved family, friends, card playing, Mozart, Chopin, Beethoven and Picasso, Monet and books: they modeled for their childrentraditional first-generation American values: work hard ... be the besf you can... life is fair... always be kind to others." The quality of perseverance and the constant need to do better incui- cated in him during his childhood and youth were to become a hallmark of his professional career, and they have also contributed to making Harold Slavkin the attractive and somewhat unusual figure he is today. Shortly after the Korean War, at the tender age of 17, Slavkin joined the US Army Dental Corps as a technician and began work at the Walter Reed Army Medical Center's huge dental iaboratory in Washington D.C., where he remained for three years. The money saved during his army service was put towards a University education, and he graduated from the University of Southern California in 1961. He was then hired as Research Technical Assistant by the Department of Anatomy of the University of California's School of Dentistry and Medicine at Los Angeles and, once again, Slavkin put the money earned there to good use: his savings funded his studies in dentistry and he was awarded his -Address for reprints: Department of Cell Biology, School of Medicine, University of the Basque Country, £-48940 leioa, Spain. FAX: 34.44648966. 0214-62X2/95/S03.00 OURC I'fcn "rinlcd in Sr~in - -