32 Australian Dental Journal, February, I968 The cariostatic effect of calcium sucrose phosphate in a group of chidren aged 5- 1 7 yearsy Robert Harris,t Rerso G. Schamschula,tt John Beveridge,ttt Geoffrey Gregory $ Introduction A preliminary report on the planning and establishment of a clinical trial of the emcacy of calcium sucrose phosphate as a cariostatic agent was published in 1967.'" A number of institutions in New South Wales were selected and agreed to participate in the trial. The children, aged 5-17 years, who formed the subjects of the trial were boarders living for the major portion of each year in the institutions. The institutions were classified either as Treatment or Control. In the case of the. former, calcium sucrose phosphate at the rate of 4.3 gm. per child per day was added to certain of the refined carbo- hydrates eaten by the children. A central organization was responsible for the preparation and distribution of these refined carbohydrate foods for the Treatment Group and samples of these treated foods were analysed weekly to ensure the consumption of the food followed the requirements of the plan for the trial. *Financial support for this project has been given by the Colonial Sugar Refining Company Ltd., and the assistance of Mr. R. Rutledge and Mr. P. Lambert in the computational work is appreciated. t Director, Institute of Dental Research, Sydney. tt Research Fellow in Dental Science, Institute of Dental Research, Sydney. ttt Professor of Paediatrics and Head of the School of Psediatrics, University of New South Wales. $ Reader, Department of Statistics, University of Melbourne. (')Harris, R., Schamschula, R. G., Gregory, G., Roots, Miriam, and Beveridge, J.-Observations on the cariostatic effect of calcium sucrose phosphate in a group of children aged 5-17 years. Preliminary report. Austral. D. J., 12 : 2, 105-113 (April) 1967. Medical supervision of the children was carried out by staff from the School of Paedia- trics, University of New South Wales. The dental observations were made by one of us (R.S.) under standard conditions based on the proposals similar to those of the Federation Dentaire Internationale Commission on classification and statistics for oral condi- tions [Principal requirements for controlled clinical trials].$$ The incidence of new carious lesions in the children in the Treatment Group was compared with the incidence in children of similar ages in the Control Group. At the end of one year of the trial there was a significant reduction in dental caries increment in children 5-12 years of age from the Treatment Group. This paper surveys the results of the trial for the first two years. Materials and methods The trial commenced in February, 1965, with the participation of a total of 1,506 children aged 5-17 years living in 19 institutions. Three of the institutions have sections for both boys and girls and for the purpose of analysing the data such sections are considered separately. Throughout the trial some children left the institutions and were replaced by newcomers; separate analyses were performed for the data obtained from them and will be considered in the final analysis at the conclusion of the trial. $$ Principal requirements for controlled clinical trials. Ed. 0. Backer Dirks, L. J. Baume, G. N. Davies, G. L. Slack. Int. D. J., 17: 1, 93-103 (Mar.) 1967.
Transcript
32 Australian Dental Journal, February, I968
The cariostatic effect of calcium sucrose phosphate in a group of chidren aged 5- 1 7 yearsy
Robert Harris,t Rerso G. Schamschula,tt John Beveridge,ttt Geoffrey Gregory $
Introduction
A preliminary report on the planning and establishment of a clinical trial of the emcacy of calcium sucrose phosphate as a cariostatic agent was published in 1967.'"
A number of institutions in New South Wales were selected and agreed to participate in the trial. The children, aged 5-17 years, who formed the subjects of the trial were boarders living for the major portion of each year i n the institutions. The institutions were classified either as Treatment or Control.
In the case of the. former, calcium sucrose phosphate at the rate of 4.3 gm. per child per day was added to certain of the refined carbo- hydrates eaten by the children.
A central organization was responsible for the preparation and distribution of these refined carbohydrate foods for the Treatment Group and samples of these treated foods were analysed weekly to ensure the consumption of the food followed the requirements of the plan for the trial.
*Financial support for this project has been given by the Colonial Sugar Refining Company Ltd., and the assistance of Mr. R. Rutledge and Mr. P. Lambert in the computational work is appreciated.
t Director, Institute of Dental Research, Sydney. t t Research Fellow in Dental Science, Institute
of Dental Research, Sydney. t t t Professor of Paediatrics and Head of the
School of Psediatrics, University of New South Wales.
$ Reader, Department of Statistics, University of Melbourne. (')Harris, R., Schamschula, R. G., Gregory, G.,
Roots, Miriam, and Beveridge, J.-Observations on the cariostatic effect of calcium sucrose phosphate in a group of children aged 5-17 years. Preliminary report. Austral. D. J., 12 : 2, 105-113 (April) 1967.
Medical supervision of the children was carried out by staff from the School of Paedia- trics, University of New South Wales.
The dental observations were made by one of us (R.S.) under standard conditions based on the proposals similar to those of the Federation Dentaire Internationale Commission on classification and statistics for oral condi- tions [Principal requirements for controlled clinical trials].$$
The incidence of new carious lesions in the children in the Treatment Group was compared with the incidence in children of similar ages in the Control Group. At the end of one year of the trial there was a significant reduction in dental caries increment in children 5-12 years of age from the Treatment Group.
This paper surveys the results of the trial for the first two years.
Materials and methods The trial commenced in February, 1965, with
the participation of a total of 1,506 children aged 5-17 years living in 19 institutions. Three of the institutions have sections for both boys and girls and for the purpose of analysing the data such sections a r e considered separately.
Throughout the trial some children left the institutions and were replaced by newcomers; separate analyses were performed for t h e data obtained from them and will be considered in the final analysis at the conclusion of the trial.
$ $ Principal requirements for controlled clinical trials. Ed. 0. Backer Dirks, L. J. Baume, G. N. Davies, G. L. Slack. Int. D. J., 1 7 : 1, 93-103 (Mar.) 1967.
Australian Dental Journal, February, I968
All the institutions boarded the children for the major portion of the year and during this time the food supplies to the Treatment Group were controlled so tha t 4-3 gm. of calcium sucrose phosphate per child per day was main- tained.
The participating institutions were allocated to either Control or Treatment Group by the following considerations :
Fluoride
Control . . 36
3 3
Non- Total fluoride
443 479
balance of numbers; balance of ages; balance of sexes; willingness of the controlling authorities of an institution to participate in the Treat- ment Group; random allocation.
to maintain the general dietary patterns that existed a t the commencement of the trial.
The Control Group consisted of 86.5 per cent boys and the Treatment Group 71.7 per cent boys. The procedures and criteria as reported(1) were followed throughout the two years and permanent teeth only were examined for the recording of dental caries incidence.
Analyses of variance on the increments in D.M.F. surfaces for each subject were carried out using the standard procedure described in Davies.‘” The components of variance con- sidered were “between treatment and control groups”, “between institutions within treatment and control groups”, and “within institutions”. The analyses considered all surfaces and the
Treatment . . 23 219 242
-- Total . . )IIrl 662 ITT
The numbers of children included in observa- tions for this two-year programme and divided into Control and Treatment Groups were:
Control Treatment Total 1965 886 621 1506 1966 632 408 1030 1967 479 242 721
While the majority of institutions were Situ- ated in non-fluoridated areas, four institutions (two Control, two Treatment) were located in a country town having a fluoridated water supply for approximately four years prior to the commencement of the trial. The results of the observations in the two areas have been treated separately.
The numbers in the two areas are shown in Table 1.
Initially there was a n imbalance in age between the two groups of children and a boarding school for boys was included i n the Control Group to restore the balance five months afte.r the initial examination. Conse- quently the “first year” for this institution covers a period of seven months. A dietitian made regular visits to all institutions in order
proximal surfaces of bicuspid and molar teeth alone. Comparisons were made on increments in D.M.F. surfaces in subjects examined in 1965 and 1967, and on increments between 1966 and 1967 for subjects present in 1965 and not present in 1965.
Results The dental caries experience of the 662 chil-
dren in non-fluoride areas, expressed as D.M.F. teeth per subject at the commencement of the trial and at the end of two years, is shown in Table 2. It will be noted that initially the average numbers of caries free teeth per subject were very similar for the two groups, although the numbers of erupted teeth in the Control Group were greater. After two years the subjects in the Treatment Group had an average of 2.72 more caries free teeth than the subjects in the Control Group. The total number of erupted teeth was comparable.
An analysis of the incidence of dental caries expressed as mean D.M.F. surfaces increment is shown in Table 3 and is compared with that of children present during 1966-1967 only.
(*) Davies, 0. L.-Statistical methods in research and production. Edinburgh, Oliver and Boyd, 3rd ed., revised, 1957 (pp. 109-114).
34
1965 - - ~ _ _ - _ _ Teeth per child
Control I Treatment
Australian Dental Journal, February, I968
1967
Control I Treatment
TABLE 2 Mean DMF teeth per rhild of 662 children of the Comirol and l’reatnaent Groups residing in
nun-.fluwide a r m (1965-1,067)
Sex
DMF Surface Increments for Boys and Girls ~ _ __ . ___._ _ _
Age Group Present a t 1965, 1966 and 1967 examinations Present a t 1966, 1967 examinations only
I t will be noted that there is a difference in D.M.F. surface increment ranging from 13 per cent in the girls 11-17 years to 25.8 per cent in the boys of the same age group whilst the younger children had similar increments for the two years. In those children present for one year there is a wider range of differences: 58.20 per cent for the girls and 17.60 per cent for the boys at 11-17 years, whereas in the younger girls the Treatment Group, certainly smaller in number, had more than twice the number of carious surfaces than the Control Group.
An analysis of the surfaces of the teeth showed that there is a difference in the effe.c- tiveness of the cariostatic properties of the additive depending upon the region of the mouth.
Table 4 shows that if the proximal surfaces of the bicuspid and molar teeth of the Control and Treatment Groups are compared, there is 50 per cent and 58.6 per cent less increment of dental caries respectively for girls and boys aged 11-17 years. The reduction for those chil- dren aged 5-10 years is between 20 and 40 per cent.
TABLE 3 T h e increment of dental cariea ezpremed as DMF surfaces in thc Control (443) and Treatment (219) Uroup& of children for the yeam 1965-1967 compared with two groups (Control 145, Treatment 127) of children ywent
for the qear 1966-1967
Boys . . 1 6-10 1 1 91 29
Boys . _ 11-17 c I I T ! fzi Diflerenca (per cent)
100 (Average Control --Avarage Treatment). Average Control
Difference=
* Significant at 5% level. ** Significant a t 1% Icvel. C : Control subjects. T : Treatment subjects. N : Number of subjects.
Australian Dental Journal, February, I968 35
The observations made on the children living in the fluoridated area are shown in Table 5 and the difference in the increment is approxi- mately 42 per cent. It will be noted that the age of the Control Group children was similar to that of those in the Treatment Group (10.2- 10.5 years) and that the latter had initially a somewhat higher D.M.F. teeth rate per child than that of the Control Group. The increase in D.M.F. teeth for the Treatment Group was about 42 per cent less (2.35-4.06). It should also be noted that the initial D.M.F. teeth per child is about half that of children living in non-fluoride areas.
A comparison of the dental caries increment between the children resident in fluoride and non-fluoride areas is shown in Table 6, where the numbers of children have been divided into two age groups. It will be noted that in the 11-17 years of age fluoride group there is a difference in favour of the children receiving the additive of 72.9 per cent. The difference noted in the 11-17 years non-fluoride group for proximal surfaces of bicuspid and molar teeth is 55.8 per cent. The total number of children in the fluoride plus calcium sucrose phosphate group is, however, small.
Discussion
The role of phosphates in dental caries has been reviewed in the literature and a brief commentary was presented in the preliminary report'l) of this study. The subject was exten- sively discussed in the Conference on Phos- phates and Dental Caries in 1962.@) The chair- man of that conference, in his introductory remarks, referred to the way in which he and his colleagues had, in 1950, stumbled on the discovery that phosphates are effective in pre- venting dental caries in rodents.
Before this time numbers of papers had been presented on the influence of dietary calcium and phosphorus upon tooth formation by Gaunt and Irving") and Agnew, Agnew and Tisdall.@) Klein and McCollum(e) had demonstrated that
' 8 ) Harris, R. S.-Definition and objectives of the Conference on Phosphates and Dental Caries. J. D. Res., 4 3 : Suppl. 6, 999-1001 (Nov.-Dec.) 1 9 6 4 .
( 4 ) Gaunt, W. E., and Irving, J. T.-The influence of dietary calcium and phosphorus upon tooth formation. J. Physiol.. 9 9 : 1, 18-29 (Dec.) 1 9 4 0 .
(5) Agnew, Mary C., Agnew, R. S., and Tisdall, F. F.-The production and prevention of dental caries. Am. D. A. J., 2 0 : 2 , 193-212 (Feb.) 1933 . Y
(0) Klein, H., and McCollum, E. V. A.-A preliminary note on the significance of the phosphorus intake in the diet and blood DhosDhorus con- centration in the experimental production of caries immunity and caries susceptibility in the rat. Science, 7 4 : 662 (Dec.) 1931 .
low phosphorus diets were cariogenic in rats. Osborn,'?) having previously studied the relation between diet and dental caries in the South African Bantu, demonstrated that decalcifica- tion of extracted teeth in witro was slower when they were incubated with crude cereals and with sugar cane juice than with reflned carbo- hydrates. He found that certain calcium and phosphate salts could protect teeth from decal- cification in witro when they were incubated in saliva plus sucrose or saliva plus refined flour. His results suggested that phosphates gave better protection if in inorganic form and calcium gave better protection if in organic form.
There are more than 100 studies of trials of phosphate in animals, mostly rodents, and these have been reviewed by Nizel and Harris.@) More recently Beveridge, Harris, Gregory and Savage(O) referred to the subject. However, i t should be noted that the calcium and phosphate concentrations of human saliva are higher than rat saliva and the pH is lower.(l0)
There are marked differences between results achieved in the use of phosphates as cariostatic agents in rodents' teeth and in the teeth of humans. There are probably many reasons for this among which, in addition to those men- tioned, are caries susceptibility of the animals, the oral microflora, length and frequency of feeding periods, care and housing of the animals, and the stage of maturation when the teeth are exposed to the diet.
Previous reports'") (-) 0') from studies on schoolchildren suggested a n equivocal result
(7)Osborn T. W. B.-Further studies on the in vitro'decalcification of teeth. J. D. Res., 20 : 1 , 59 -69 (Feb.) 1941 .
(s)Nizel, A. E., and Harris, R. %-The effect of phosphates on experimental dental carles : a literature review. J. D. Res., 4 3 : Suppl. 6, 1123-1136 (Nov.-Dec.) 1 9 6 4 .
(8) Beveridge J. Harris, R., Gregory, G., and Savage, D. C. L.'-Prevention of dental caries : 1 . Phos- phates and dental caries. Med. J. Aust., 2 : 2 , 54-57 (July 8 ) 1967 .
(10) Brudevold F Amur, B. H., Vogel, J. J., and Spinelli, M.2Effect of ingested supplementary phosphate on the tooth surface. J. D. Res., 4 3 : Suppl. 6, 1168-1176 (Nov.-Dec.) 1964 .
(u) Str%lfors, A.-The effect of calcium phosphate on dental caries in school children. J. D. Res., 4 3 : Suppl. 6, 1137-1143 (Nov.-Dec.) 1964 .
(12) Ship, I. I., and Mickelsen, 0.-The effects of calcium acid phosphate on dental caries in children : a controlled clinical trial. J. D. Res., 4 3 : Snppl. 6, 1144-1149 (Nov.-Dec.) 1964 .
(Ya) Averill, H. M., and Bibby, B. G.-A clinical test of additions of phosphate to the diet of children. J. D. Res., 4 3 : Suppl. 6, 1150-1155 (Nov.-Dec.) 1964 .
(I4) Averill. H. M.. Friere. P. S.. and Bibbv. B. G.- The effect of' dietary phosphate supplkments on dental caries incidence in tropical Brazil. Arch. Oral Biol.. 11 : 3, 315-322 (Mar.) 1966 .
36 Australian Dental Journal. February, I968
1965-1967
1.79 1.07
40.20
6.40 2.61
58.60**
_ _ _ _ _
T-4RLE 4 The increment of dmtul caries of% the proximal surfwee of the bicuapid aid ntolar teeth of the ti62 children i n the
clinical trial fov the two years compared with t l t d of the children wesent .for one year
N
46 15
~-
-
59 92
2.10 1.68
20.00
5.94 2.97
50.00**
22 9
~ -
18 11
Age (Fa.)
Mean DMF Surfaces lncrement _ _ _ _
Non-fluoride __
No. I DMFS
Fluoride
No. I DMFS
I DMF Surface Increments for Boys and Girls
sex 1 Age Group Present a t 1966, 1967
Present at 1965, 1966 and 1967 examinations examinations only -~
100 (Avorage Control-Average Treatment). Average Control Difference =
* Significant at 5% level. ** Significant at 1% level. C : Control mbjects. T : Treatment subjects. N : Number of subjects.
TABLE 5 Mean DMF teeth per child of 59 children of both, Control and Treotrnenl Groups living i n a flwrridded area
(1965-1967)
DMF teeth per child Difference 1966-1967
~~ No. of I Age 1 children 1965 1 1066 1 1967
Control . . . . 1 36 1 10.2 1 4.33 I 6.11 I 8.39 I 4.06
Treatment 1 23 1 10.5 I 4.61 1 5.74 1 6.96 1 2-36
TABLE 6 Mean DMF slirfacea increment for all children (721) aged 5-17 years living i n ,both fluoride and non-fluuride
nrms (1965-1967)
Cont.rol 4.28 (0.61) 11-17 I :: I 15.00 (4.44)
120 8.18 (1.89) 323 I 15.14 (6.26**)
Treatment . . ~ ~~~~ ~
4.00 (-0.15) 11-17 7.40 (1.30)
Total I 59 I 662 I N.B.-Figures in brackets are for proximal surfaces on bicuspid and molar teeth. ** Significant at, 1 per cent. level.
Australian Dental Journal. February, I968
could be expected when calcium phosphate, calcium acid phosphate or dicalcium phosphate was used as a food additive to certain refined carbohydrate foods.
In the trial reported here indications were clear a t the end of one year that some beneficial effect was apparent in the use of the calcium sucrose phosphate as a food additive.") It was shown that when the additive at the average daily rate of 4.3 gm. per child was regularly eaten, even though not for the whole year, there was a reduction in dental caries per child 5-8 years of age of 1.42 surfaces, 9-12 years of age of 1.97 surfaces, and 13-17 years of age of 1.25 surfaces. Considered by ages this reduction is significant for children aged 5-12 years.
Furthermore, the medical investigations showed no differences, in growth or other physical factors, between the children of the Control and Treatment Groups.
Since it is inevitable that all the children will not remain in the homes throughout the trial, some loss of subjects occurs. Nevertheless, of the original 1,506 children 721 had partici- pated throughout and were present at the end of two years.
Because of this loss in numbers the results have been reported for the age groups 5-10 and 11-17 years only.
The initial dental examinations made in 1965 of the children in the non-fluoride areas showed somewhat more caries in the Control Group and this group had on average more teeth per child. Furthermore, it should be noted that the addi- tion, five months after the commencement of the trial, of a number of boys reduces their first year to seven months. This could only produce bias in favour of the Control Group in the subsequent analysis.
In 1967 the numbers cf erupted teeth per child were for all practical purposes equal and the children of the Treatment Group had 2.62 less carious teeth per child than those of the Control Group.
The cariostatic effect is consistent and shows an improvement of approximately 25 per cent in favour of the Treatment Group (Table 3 ) . In only three analyses, however, can statistical significance be claimed and then only a t the five per cent level. The pattern in Table 4 is fa r more convincing. Here the result is assessed for proximal surfaces of bicuspid and molar teeth. Not only are the reductions greater and more consistent, but there are now flve instances of significance a t the one per cent
37
level. Subjects were subdivided by age into the two sub-groups covering the ranges 5-10 years and 11-17 years in 1965. This was done to make variability within a sub-group more homogeneous. It is based on experience with data from the first year and supported by data from Barnard.(=) In Table 4 significance is conflned to the older age groups. Similar rela- tive results have been demonstrated for the younger groups but since eruption count of the bicuspid and molar teeth is considerably less in these groups the true effect may have been obscured by the inherent variability oper- ating over a smaller effective population.
In the Control Group, aged between 11-17 years in 1965, 41-4 per cent of all D.M.F. sur- faces observed during the trial were in the proximal surfaces of the bicuspid and molar teeth. It is estimated that the addition of calcium sucrose phosphate to the diet has reduced the incidence of caries in these surfaces by 50 per cent.
Of particular importance is the cumulative effect in reducing caries increment for those children resident in the fluoridated area. At the commencement of the study those children with a n average age 10.2-10.5 years had a D.M.F. index of 4.57 (Table 5 ) compared with D.M.F. 7.98 in the non-fluoridated area (Table 2 ) . At the end of the two years the D.M.F. index for the Control Groups was 13.48 and 8.39 and for the Treatment Groups 10.82 and 6.96 (Tables 2, 5 ) .
Both the increments in D.M.F. teeth are less than the corresponding values in the other institutions. There is also a reduction in this measurement in favour of the calcium sucrose phosphate diet.
Some idea of the interaction between the effects on teeth of fluoridated water and of calcium sucrose phosphate may be deduced from Table 6 in which is shown the average increase of D.M.F. surfaces and the average increase of D.M.F. proximal surfaces per subject. Both effects are beneficial with fluoride showing the largest improvement in the younger group and calcium sucrose phosphate appears to be the better agent in the older group. Significance tests carried out show the difference to be a t the 1 per cent level for calcium sucrose phosphate in the fluoridated area for older children. The evidence indicates that the
(16) Barnard, P. D.-Dental survey of State school children in New South Wales, Jan. 1984-June 1955. N.H.M.R.C. Su. Rut. Series No. 8. Can- berra, 1956
38 Australian Dental Journal, February, I968
and 12.38 years respectively. No significant differences in the initial D.M.F. teeth were observed in those who remained at the end of 2.5 years in the three groups of children. At the end of 2.5 years there was a significant reduction in the sugar f phosphate group in D.M.F. surfaces. No significant difference was observed when considering teeth only. A similar trend was revealed when the group that chewed the sugar gum was compared with the group that chewed the sugarless gum. When the group that chewed the sugarless gum was compared with the group that chewed the sugar + phos- phate gum there was no appreciable difference between them whether teeth or surfaces were compared. If proximal surfaces of all teeth were considered the group that chewed the phosphate gum showed “a statistically signifi- cant mean difference in all of the computations over the group that chewed the sugar gum amounting to between 39.7 and 52.9 per cent”. The difference between sugarless gum and phos- phate gum was less. It is interesting to note that these studies showed a greater effect in the proximal areas. Chewing gum involves posterior more than anterior teeth as well as promoting a greater salivary flow and one might expect therefore that they would show greater effect. It should be noted that each child chewed five strips of gum for 20 minutes daily (two sticks between breakfast and lunch, one stick after school and two after dinner in the evening) and that the posterior teeth of all children appeared “unusually clean” compared with the upper anteriors.
Chewing gum as a vehicle for introducing cariostatic agents to the oral cavity has been used, for example incorporating synthetic Vitamin K.”J
The incorporation of the cariostatic agent in food has a distinct advantage over i ts use in a chewing gum. It does not require any addi- tional cooperation from the subjects nor a change i n the habits and practices. Chewing gum is not universally acceptable.
The incorporation of the cariostatic agent in one refined carbohydrate food only also has the disadvantages that the food may not be taken at every meal, i t may be chewed in limited degree and its effect may be overwhelmed by the amounts and effect of the other carbo- hydrates. The placing of the calcium sucrose phosphates in a number of the refined carbo-
effects of the two preventive measures are addi- tive. A similar hypothesis was suggested by the results of studies on rats by Lilienthal.(leJ
Str%lfors(’’) using radiographic examination of the upper incisor teeth found a reduction of G O per cent in the first year and 44 per cent in the second year. Dibasic calcium phosphate was mixed i n a n amount of 2 per cent into four ingredients of the school luncheon food- soft bread, hard bread, wheat flour used for cooking and sugar. The source of phosphate was changed a t the end of the first year since i t had been found that some samples contained 250 ppm. fluorine. Stookey, Carroll and Muhler(17) observed the effect on caries of 1.0 per cent NaH,PO, when added to presweetened ready-to-eat breakfast cereals and noted a reduc- tion of between 40 and 20 per cent in D.M.F.S. increment. Their study reported results on 500 children after two years and the observa- tions were made by two examiners. It should be noted that a t the end of the first year of their trial Na,HPO, was added so that the cereals contained 1 per cent of a mixture of NaH,PO, and NhHPO,. Apparently the 1 per cent NaH,PO, altered the taste of the cereal product. The addition of the N&HPO, is not mentioned as playing any role as a cariostatic agent. The authors noted a “preferential effect of the phosphates in the reduction of the incidence of new lesions on proximal surfaces during the flrst year of the study”. This was maintained during the second year a t a lesser rate. Other studies are in progress. Finn and Jamison(’) and Finn(1e) observed the effect of dicalcium phosphate dihydrate added to chewing gum used by 138 children aged 6-18 years and resident in school about nine months of the year. The additive amounted to 225 mg. per stick of sugar gum and its effect was compared with a group of children who chewed sugar coated gum and another group using sugarless gum. The average age of the children was 12.36, 12.45,
(10) Lilienthal, B., Bush, Elizabeth, Buckmaster. M., Gregory, G.. Gagolski, J., Smythe. B. M., Curtin, J. H and Napper, D. H.-The cariostatic effect ”of carbohydrate phosphates in the diet. Austral. D. J., 11: 6, 388-395 (Dec.) 1966.
(17) Stookey, G. H., Carroll, R. H., and Muhler, J. C.-The clinical effectiveness of phosphate enriched breakfast cereals on the incidence of dental caries in children: results after two years. J.A.D.A., 7 4 : 4 . 752-758 (Mar.) 1967.
Finn, S. B., and Jamison, H. C.-The effect of dicalcium phosphate chewing gum on caries incidence in children: 30 month results. J.A.D.A., 7 4 : 5, 987-995 (Apr.) 1967.
(lD) Finn, S. B.-The role of dicalcium phosphate chewing gum in the control of human dental caries. Int. D. J.. 1 7 : 2, 339-352 (June) 1967.
Burrill. D. Y., Calandra. J. D., Tilden, E. B., and Fosdick, L. S.-Effect of Z-methyl-1,4- naphthoquinone on the incidence of dental caries. J. D. Res., 2 4 : 6, 273-282 (Dee.) 1945.
Australian Dental Journal, February, I968
hydrate foods would tend to eliminate. those disadvantages.
The results of our study can be compared with those of Stookey, Carroll and Muhler,(17) Finn and Jamison(”) and Finn.(18)
That the greater reduction is observed in posterior teeth has considerable practical signi- ficance since these surfaces are difficult to restore. Furthermore, we must agree with Stookey, Carroll and Muhler that such lesions a re frequently overlooked by the patient and hence are least likely to be restored and often require. extensive tooth preparation to gain access for the operative procedures.
Summary
The results of a controlled clinical trial of calcium sucrose phosphates as food additives
39
in certain refined carbohydrate foods for two years are reported.
There is a n overall reduction of approxi- mately 25 per cent in caries increment in the mouths of children eating the treated food and this reduction is mainly demonstrated in the proximal surfaces of posterior teeth which show more than 50 per cent less caries.
The effect of calcium sucrose phosphates is additional to that noted from fluoridated water. Calcium sucrose phosphates are safe, soluble and readily incorporated in various foods. The study is continuing.
The Institute of Dental Research, United Dental Hospital,
2 Chalmers Street, Surry Hills, N.S.W. 2010.
Tmorrow In research, pay-off8 in a therapeutic, curative, or preventive triumph do not come piecemeal, but like the jackpot after an indefinite and usually costly number of trials. Such dental jackpots are in the making and their impact will be significant but not threatening. From early studies of communities that have been fluoridating their water supply for a number of years, it is already becoming apparent that the changing dental health situation does have an effect on the nature of the demand for service. There are fewer emergency cases, a lessening demand for reparative work, and a related decline in the amount of endodontal and periodontal disease. These are offset by an increase in the demand for oral health care with emphasis on maintenance and the correction of malocclusion. They see more patients per day and have increased incomes. Somewhat curiously, t.he demand for oral surgery does not appear to change. Although these observations are no more than preliminary readings from fluoridated districts, they suggest that preventive measures in dentistry, far from eliminating the need for dentists, will have the reverse effect. This is precisely what happened in the field of medicine.-Roy 0. Greep, Harvard Dental Alumni Bulletin, Spring, 1967.
