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The pattern of progressive mineralisation in human dental enamel
Arch. orrrl Bill.
V01.7, pp.655-656,
1962.
Pergamon Press Ltd.
BOOK H. S. M.
CRABB
Enamel.
International
Printed in Ct. Britain.
REVIEWS
and A. I.
DARLING: The Pattern of Progressive Mineraiisation in Human Dental &vies of Monographs in Oral Riology, No. 2. Pergamon Press, Oxford,
1962. 100 pp., 3%. monograph, the second of a series on oral biology, CRABB and DARLING examine the available evidence on the anatomical pattern of mineral accretion within developing human dental enamel. Starting with a rCsumC of the results obtained and the theories propounded by earlier workers, the authors consider in detail the findings of the recent independent studies of HAMMARLUND-ESSLER, CRABB and ALLAN, which used microradiography, polarization microscopy and decalcified material. The four chapters devoted to this consideration form the basis of the monograph, which concludes with two short discussions and a summary. The chapter dealing with the recent microradiographic studies describes the essentially centrifugal mineralization pattern observed by all three workers: the variations therein found in the surface zone, striae of Retzius, rods, and central parts of the enamel; and includes a section on quantitative assessment. There seems to be almost complete agreement on both the observations and the interpretation thereof presented in this chapter, although the diagram illustrating the basic pattern may well over-emphasize the concavity of the mineralization front. Then follow the results of the recent polarization microscopy studies, which again shou a large measure of agreement, and confirm the mineral distribution shown by microradiography. However, the conclusion of the monograph’s authors, that the differences between the values obtained for the intrinsic and the form birefringence in the quantitative studies indicate a withdrawal of organic material from the enamel matrix, is not beyond criticism. The recent studies on decalcified material, described in Chapter 7, undoubtedly form the least coherent section of the monograph, as the authors themselves recognize. The nature and the significance of the alterations within the decalcified organic matrix which result in staining changes and matrix loss and “solubility”, remain obscure. While the variable results reported in the staining of the enamel matrix, particularly in the surface zone, and misunderstandings on the interpretation of matrix “solubility”, highlight the uncertainty and divergence of opinions which still exist in this part of the subject. Perhaps, however, it is in the discussions that the central difliculty associated with the decalcified material emerges most clearly. Here we recognize the limitations of the staining affinity and “solubility” of the matrix as guides to the overall mineralization pattern, but neverthcless accept the importance of the matrix in mineralization processes, and realize the frequent concurrence of mineral and matrix defects. This excellent monograph gives a balanced assessment of present knowledge on the subject. The authors and the publishers are to be congratulated on a book well produced and lucidly written, which includes numerous good photomicrographs, some in colour, and a comprehensive reference list. J. H. AI L.AK IN THIS
T. ROSEBURY: $15.00.
Microorganisms
Indigenous
to Man.
McGraw-Hill,
New York,
1962. 435 pp.,
Microorganisms Indigenous to Man provides a comprehensive treatment of a subject which has never been dealt with previously in a systematic and satisfying way. This is not to suggest that the topics dealt with have been neglected, though this idea is implied in a sense in the author’s Preface. He states that “this book has come to deal with the more neglected microorganisms of medical importance”. “Neglected” they have been as far as any such total treatment as offered here is concerned; but the literature, as proven by the author’s heroic coverage, is enormous. To most readers the range and diversity of investigations in this whole field, as disclosed in the pages of this book, will come as a surprise. The listing of quoted references following the eleven chapters occupies seventy-six pages and this fact alone is evidence for the need for a book of this
655
V01.7, pp.655-656,
1962.
Pergamon Press Ltd.
BOOK H. S. M.
CRABB
Enamel.
International
Printed in Ct. Britain.
REVIEWS
and A. I.
DARLING: The Pattern of Progressive Mineraiisation in Human Dental &vies of Monographs in Oral Riology, No. 2. Pergamon Press, Oxford,
1962. 100 pp., 3%. monograph, the second of a series on oral biology, CRABB and DARLING examine the available evidence on the anatomical pattern of mineral accretion within developing human dental enamel. Starting with a rCsumC of the results obtained and the theories propounded by earlier workers, the authors consider in detail the findings of the recent independent studies of HAMMARLUND-ESSLER, CRABB and ALLAN, which used microradiography, polarization microscopy and decalcified material. The four chapters devoted to this consideration form the basis of the monograph, which concludes with two short discussions and a summary. The chapter dealing with the recent microradiographic studies describes the essentially centrifugal mineralization pattern observed by all three workers: the variations therein found in the surface zone, striae of Retzius, rods, and central parts of the enamel; and includes a section on quantitative assessment. There seems to be almost complete agreement on both the observations and the interpretation thereof presented in this chapter, although the diagram illustrating the basic pattern may well over-emphasize the concavity of the mineralization front. Then follow the results of the recent polarization microscopy studies, which again shou a large measure of agreement, and confirm the mineral distribution shown by microradiography. However, the conclusion of the monograph’s authors, that the differences between the values obtained for the intrinsic and the form birefringence in the quantitative studies indicate a withdrawal of organic material from the enamel matrix, is not beyond criticism. The recent studies on decalcified material, described in Chapter 7, undoubtedly form the least coherent section of the monograph, as the authors themselves recognize. The nature and the significance of the alterations within the decalcified organic matrix which result in staining changes and matrix loss and “solubility”, remain obscure. While the variable results reported in the staining of the enamel matrix, particularly in the surface zone, and misunderstandings on the interpretation of matrix “solubility”, highlight the uncertainty and divergence of opinions which still exist in this part of the subject. Perhaps, however, it is in the discussions that the central difliculty associated with the decalcified material emerges most clearly. Here we recognize the limitations of the staining affinity and “solubility” of the matrix as guides to the overall mineralization pattern, but neverthcless accept the importance of the matrix in mineralization processes, and realize the frequent concurrence of mineral and matrix defects. This excellent monograph gives a balanced assessment of present knowledge on the subject. The authors and the publishers are to be congratulated on a book well produced and lucidly written, which includes numerous good photomicrographs, some in colour, and a comprehensive reference list. J. H. AI L.AK IN THIS
T. ROSEBURY: $15.00.
Microorganisms
Indigenous
to Man.
McGraw-Hill,
New York,
1962. 435 pp.,
Microorganisms Indigenous to Man provides a comprehensive treatment of a subject which has never been dealt with previously in a systematic and satisfying way. This is not to suggest that the topics dealt with have been neglected, though this idea is implied in a sense in the author’s Preface. He states that “this book has come to deal with the more neglected microorganisms of medical importance”. “Neglected” they have been as far as any such total treatment as offered here is concerned; but the literature, as proven by the author’s heroic coverage, is enormous. To most readers the range and diversity of investigations in this whole field, as disclosed in the pages of this book, will come as a surprise. The listing of quoted references following the eleven chapters occupies seventy-six pages and this fact alone is evidence for the need for a book of this
655