CORRESPONDENCE
Fluoridation Sir,--I was somewhat amazed to read in your editorial comment in your issue of June, 1957, that fluoridation" " . . . will not, of course, reduce the incidence of orthodontic defects . . . . " This statement would, I am sure, scarcely meet with general acceptance by dentists. The Scottish Health Services Council's publication "Preventive Dental Services," 1952, has this to say: "We wish to emphasise that premature loss of teeth in children is not just a loss in itself but is a piling-up of trouble for the future." There are, of course, a number of orthdontic problems which do arise whether there has been early loss of teeth or not, but every dental officer is only too well aware of the orthodontic troubles which are the direct result of early loss of deciduous teeth and first permanent molars. The reports of ten-year fluoridation studies in U.S.A. and Canada clearly show the great reduction in dental caries of both deciduous and permanent dentitions which fluoridation can achieve. The greater caries resistance offered to deciduous teeth by fluoridation and their consequent retention for a longer period cannot but lessen the hazard of malocclusion of the permanent dentition. It is also somewhat surprising to read that fluoridation of water supplies should still be looked at askance in official quarters. The ministerial remarks in reply to a debate in Parliament on the shortage of dentists (H. of C. Hansard, March 8th, 1957) would certainly not suggest any such thing. It would not seem that it is up to all who are interested in preventive dentistry, particularly in its broader aspect as a part of preventive medicine, to make an energetic start in paving the way for a further extension of the fluoridation areas in this country by the education of the lay public, and also of their professional brethren perhaps not so well informed on the subject as themselves. The fluoridation symposium at this year's Royal Society of Health Congress at Folkestone made an excellent beginning, which it is to be hoped will everywhere be forcefully followed up. West Garth, Yours faithfully, Cowley Bridge Road, Exeter, Devon. JEFFREY FLETCHER. 9th June, 1957.
BOOK REVIEW C A N N E D F O O D S : A N I N T R O D U C T I O N TO T H E I R MICROBIOLOGY. By J. G. BAUMGARTNER. (Pp. 283. Price 21s. net.) London : J. & A. Churchill, Ltd., 1956. This excellent little handbook has now appeared in its fourth edition. It is designed particularly for the food technologist, but is equally valuable to the public health inspector and to the medical officer of health. Much ground is covered and mention is made of such diverse subjects as tenderising meat by ultra violet rays, off-flavours in hams caused by faecal streptococci and the spoilage of canned food by the cooling water. The book is well worth acquiring, but there is an unfortunate error on page 13 where it is stated that a particular species of bacterium " i s variously known as Salmonella typhimurium, Bacterium enteritidis and Bacillus paratyphosus B " ! 192