I 9 9

U T I L I Z I N G DIETARY FLUORIDES;

AN APPRAISAL OF THEIR EFFECTIVENESS,

PRACTICALITY, AND SAFETY

A d e l e Montgomery, D . H .

I n t h e p a s t few y e a r s f l u o r i d a t i o n o f t he communal supp ly o f water has become a c o n t r o v e r s i a l issue--even though i t s s a f e t y and b e n e f i t s have been proved beyond a reasonab le doubt. As a r e s u l t o f t h i s con- t r o v e r s y , many a l t e r n a t i v e s f o r supp lement ing t h e d i e t w i t h f l u o r i d e s have been advocated. The f o l l o w i n g s ta tements appeared i n a l e t t e r t o the e d i t o r of t he " D e t r o i t Free Press" on October 1, 1962: "Good solu- t i o n s t o the f l u o r i d a t i o n problem have been suggested, such as s p e c i a l m i l k and f l u o r i d e t a b l e t s . I t would be cheaper f o r t h e c i t y t o a i d t h e u n d e r p r i v i l e g e d i n t h i s way. B u t no! F l u o r i d e must be i n o u r water and no s u b s t i t u t e w i l l p lease those who are pushing t h i s system." I n v iew o f t he c u r r e n t pub1 i c i t y , i t may be concluded t h a t the sa fe ty , p r a c t i c a l i t y and e f f e c t i v e n e s s o f a l t e r n a t i v e methods f o r t he sys temic a d m i n i s t r a t i o n o f f l u o r i d e s shou ld be appra ised. A c r i t i c a l examina- t i o n o f t h e p e r t i n e n t s c i e n t i f i c l i t e r a t u r e on s u p p l e m e n t a t i o n w i t h f l u o r i d e s now has become impor tan t . A l t e r n a t i v e v e h i c l e s suggested f o r t he sys temic a d m i n i s t r a t i o n o f f l u o r i d e s have inc luded t a b l e t s , 1 i q u i d p r e p a r a t i o n s , m i l k , j u i c e , t a b l e s a l t , v i t a m i n s , c e r e a l , and cherr ing gum.

R E V I E W O F THE LITERATURE

Several s t u d i e s o f t h e use o f f l u o r i d e i n t h e t a b l e t form have been repo r ted . Bibby and o thers ' repo r ted , i n 1955, t h a t the use of lozen- ges reduced c a r i o u s l e s i o n s by a c t i n g on the e x t e r n a l s u r f a c e s o f t he t e e t h and n o t because o f s y s t e m i c e f f e c t . T h i s c o n c l u s i o n was based on a study o f 119 i n s t i t u t i o n a l i z e d c h i l d r e n who chewed f l u o r i d e lozen- ges and 113 c h i l d r e n who swal lowed p i l l s c o n t a i n i n g 2.21 mg. o f sodium f l u o r i d e . A rno ld and o the rs4 , i n 1960, repo r ted a s tudy of 121 c h i l d - ren, 4-15 y e a r s o l d , i n t h e a r e a o f Washington, D. C . , who r e c e i v e d sodium f l u o r i d e t a b l e t s c a n t a i n i n g 1 . 0 mg. o f f l u o r i n e f o r an average o f t w o - t h i r d s o f t h e i r l i v e s . The de f and DMF t e e t h were found t o be comparab le t o t h o s e found i n Grand Rapids, M ich igan , 10 y e a r s a f t e r f l u o r i d a t i o n . D e r r o w l l and S i x l e r 7 repo r ted , i n 1960, t h a t when f l u o - r i d e s were admin i s te red d a i l y i n t a b l e t form, ~ l o o d l e v e l s o f f l u o r i d e remained e l e v a t e d f o r ve ry s h o r t p e r i o d s o f t ime.

A I & - y e a r s t u d y was r e p o r t e d by Fe l tman and K o s e 1 , 1 4 9 1 5 f i r s t i n 1955 and aga in i n 1961, when the research was completed. F l u o r i d e tab- l e t s were a d m i n i s t e r e d i n t h r e e forms ( c a l c i u m f l u o r i d e c o n t a i n i n g 1.0 mg. o f f l u o r i n e , sodium f l u o r i d e c o n t a i n i n g 1.2 mg. o f f l u o r i r l e and sodium mono- f l uo rphospha te c o n t a i n i n g 0.825 mg. o f f l u o r i n e ) t o

p r e g n a n t women and t o c h i l d r e n t h r o u g h t h e i r e i g h t h y e a r o f l i f e .

Conc lus ions were based on t h e f i n d i n g s o b t a i n e d from ana lyses made o f p l a c e n t a l t i s s u e o b t a i n e d f rom 332 women and 251 c o n t r o l s , f rom t h e analyses o f t he b lood from the c o r d o f 361 women and 240 c o n t r o l s , and the c l i n i c a l f i n d i n g s (DMF and d e f r a t e s ) f r o m 672 c h i l d r e n and 461 c o n t r o l s . They c o n c l u d e d t h a t f l u o r i d e i n g e s t e d by p r e g n a n t women e n t e r e d t h e m a t e r n a l c i r c u l a t i o n , was s t o r e d i n t h e p l a c e n t a and passed th rough t h e p l a c e n t a l b a r r i e r t o e n t e r t he f e t a l b lood. F luo - r i d e i n the f e t a l blood, they concluded, a f f e c t e d the deve lop ing t e e t h t o make them more r e s i s t a n t than usua l t o d e n t a l c a r i e s . F l u o r i d e s , they concluded, were b e n e f i c i a l o n l y when begun i n t h e f i r s t and sec- ond t r i m e s t e r o f pregnancy and o f no b e n e f i t when begun i n t h e t h i r d t r i m e s t e r . One p e r c e n t o f t h e women and c h i l d r e n , t hey s t a t e d , p r e - sented evidence o f undes i rab le s i d e e f f e c t s o f therapy w i t h f l u o r i d e s - - eczema, a t o p i c d e r m a t i t i s , u r t i c a r i a , e p i g a s t r i c d i s t r e s s , emesis and headache which d isappeared f o l l o w i n g the use o f p lacebo t a b l e t s , o n l y t o r e c u r when the f l u o r i d e t a b l e t was a d m i n i s t e r e d aga in .

K r u s i c l g , i n 1961, r e p o r t e d a s tudy o f t h r e e years i n d u r a t i o n c a r - r i e d o u t a t t h e U n i v e r s i t y o f L jub jana , Yugos lav ia , w i t h 168 s e l e c t e d 8 - t o 15-year -o lds , who r e c e i v e d c a l c i u m f l u o r i d e t a b l e t s d a i l y . They were examined p e r i o d i c a l l y a t t he d e n t a l c l i n i c o f t he U n i v e r s i t y . Be- f o r e i n g e s t i n g the c a l c i u m f l u o r i d e , the c a r i o u s l e s i o n s o f the c h i l d - ren , i n c l u d i n g t h e two groups o f c o n t r o l s (91 and 77 c h i l d r e n ) , had been e l i m i n a t e d by r e s t o r a t i o n s . The decrease i n the i nc idence o f new c a r i o u s l e s i o n s o f t h e exper imen ta l groups o f c h i l d r e n , when compared w i t h t h e c o n t r o l s , ranged f rom 12.93 t o 86.80 p e r c e n t . No deve lop - ment o f d e n t a l f l u o r o s i s was r e p o r t e d . The C o u n c i l on Denta l Thera- p e u t i c s o f t h e Amer ican D e n t a l A s s o c i a t i o n ' has d e s i g n a t e d t a b l e t s c o n t a i n i n g f l u o r i d e , i n t h e form o f c a l c i u m f l u o r i d e , i n group D (un- a c c e p t a b l e ) because o f t h e d i f f i c u l t y or i m p o s s i b i l i t y o f p r o v i d i n g an a c c u r a t e l y c o n t r o l l e d l e v e l o f " e f f e c t i v e " f l u o r i d e f o r t he p a t i e n t t h rough a d m i n i s t r a t i o n o f a s l o w l y s o l u a b l e f l u o r i d e .

Ziemnorwicz-Glowacka,25 i n 1961, r e p o r t e d a s t u d y o f t h r e e y e a r s d u r a t i o n i n t h e Den ta l School o f t h e Med ica l Academy o f Lodz, Poland, i n which 3,434 c h i l d r e n 3 - t o 5-years-old were fed F luodar (NaF) t a b l e t s and 3,688 c h i l d r e n s e r v e d as c o n t r o l s . The c h i l d r e n were examined p e r i u i i c a l l y and DMF t e e t h were recorded on i n d i v i d u a l c h a r t s . A f t e r t he f i r s t year, i t was imposs ib le t o draw any conc lus ions . Dur ing the second yea r o f o b s e r v a t i o n , t h e c h i l d r e n i n g e s t i n g F l u o d a r deve loped 7.1-38.5 p e r c e n t fewer c a v i t i e s than t h e c o n t r o l s . The o b s e r v a t i o n s a f t e r t h r e e yea rs i n d i c a t e d t h a t t he d i f f e r e n c e between the groups had become 21.6-42.4 p e r c e n t . The average DMF was 1.2 i n c h i l d r e n f rom s i x - t o - e i gh t - yea rs -o ld , whereas, i n the c o n t r o l s i t was 9.5. Hender- shot,18 recommended i n 1961, s ince the consumption o f f l u o r i d a t e d water by i n f a n t s was sa fe , t h a t t h e i n f a n t s younger than two y e a r s o f age shou ld be g iven w t e r c o n t a i n i n g one ppm o f f l u o r i d e r a t h e r than be ing g i ven a f i x e d amount o f f l u o r i d e .

20 I

The Counc i l on Den ta l T h e r a p e u t i c s o f t he American Den ta l Associa- t i o n , ’ i n 1958, and the Canadian Denta l A s s o c i a t i o n , * i n 1961, advised a g a i n s t i n d i s c r i m i n a t e d i s t r i b u t i on o f d i e t a r y supp lements o f f 1 uo- r i d e s . D r i n k i n g water should c o n t a i n l e s s than 0.7 ppm o f f l u o r i d e and shou ld be c a r e f u l l y ana lyzed b e f o r e supp lements a r e p r e s c r i b e d . The p r e s c r i p t i o n and t h e i n s t r u c t i o n s , wh ich change w i t h t h e age o f t he c h i l d , shou ld be w r i t t e n and p r e s c r i p t i o n s shou ld be l i m i t e d t o those ins tances i n wh ich t h e p a r e n t may be expec ted t o f o l l o w i n s t r u c t i o n s c a r e f u l l y , Since f l u o r i d e i s a po ison and may be a hazard i n the home, t h e b o t t l r shou ld be marked c l e a r l y .

Dudenbostel,12 i n 1961, s e n t q u e s t i o n n a i r e s on p o s t ca rds t o 17,848 d e n t i s t s i n the U n i t e d S ta tes , t o de te rm ine the p r e s c r i p t i o n o f f l u o - r i d e s . Responses from 12,525 (12 p e r c e n t ) o f these d e n t i s t s i n d i c a t e d t h a t 31 .1 p e r c e n t p r e s c r i b e d f l u o r i d e f o r p a t i e n t s l i v i n g i n a reas i n wh ich f l u o r i d e s were a b s e n t f r o m t h e w a t e r . F o r t y - s i x commerc ia l b rands o f f l u o r i d e - - I g i n t a b l e t fo rm and 27 i n s o l u t i o n - - w e r e b e i n g used. P r e f e r e n c e f o r t h e t a b l e t was de te rm ined as 2 : l . O f t he den- t i s t s p r e s c r i b i n g s o l u t i o n s , 83.2 p e r c e n t suggested no brand o r dosage f o r v a r i o u s ages. O f t h e d e n t i s t s s t a t i n g t h a t they “sometimes recom- mend sodium f l u o r i d e i n t e r n a l l y , ” o n l y 23.7 p e r c e n t appeared t o f o l l o w the dosages recommended by the Counc i l on Denta l Therapeut ics . O f t he d e n t i s t s i n d i c a t i n g t h a t t h e y “ r o u t i n e l y recommend NaF i n t e r n a l l y , ” o n l y 19.9 p e r c e n t appear t o f o l l o w t h e t a b l e t dosages recommended by the Counci 1.

P u b l i c Hea l th Reports,24 i n 1959, s t a t e d t h a t t a b l e t s had a p o s i t i v e e f f e c t , a l t h o u g h the exper imen ts w i t h the t a b l e t s have been performed f o r a much s h o r t e r t i m e and on a much s m a l l e r s c a l e than t h e e x p e r i - ments w i t h f l u o r i d a t e d d r i n k i n g wa te r . Con t inued r e s e a r c h on such methods o f f l u o r i d a t i o n shou ld be ancduraged. I f t h e i r e f f e c t i v e n e s s , p r a c t i c a o i 1 i t y and s a f e t y o f app l i c a t i o n can be demonstrated, they may become v a l u a b l e i n r e g i o n s where f l u o r i d a t i o n i s imposs ib le .

The Counci l on Research o f the Canadian Dental Assoc ia t i on ,8 i n 1961, s t a t e d , “There i s as y e t no re1 i a b l e ev idence r e g a r d i n g the e f f e c t i v e - ness o f f l uo r ida t .ed m i l k o r s a l t f o r the c o n t r o l o f den ta l decay. Even i f they were e f f e c t i v e , problems o f s t a n d a r d i z a t i o n would be m u l t i p l i e d w i t h the need f o r c o n t r o l a t each d a i r y o r s a l t r e f i n e r y . ”

I n the f i r s t p lace , the assumption t h a t t he use o f f l u o r i d a t e d m i l k neces- s a r i l y wou ld r e s u l t i n a r e d u c t i o n o f c a r i o u s l e s i o n s had n o t been tes ted . Secondly, i f f l u o r i d e were a v a i l a b l e o n l y i n d a i r y m i l k , many i n f a n t s would r e c e i v e l i t t l e o r none d u r i n g the f i r s t weeks o f l i f e and g row ing c h i l d r e n would o b t a i n i t i s v a r y i n g degrees depend ing on t h e i n d i v i d u a l l i k i n g f o r m i l k . T h i r d l y , t h e r e wou ld be t h e prob lem o f d e c i d i n g the a c t u a l amount o f f l u o r i d e t h a t would have t o be added t o m i l k t o ensure an i n t a k e t h a t m i g h t produce e f f e c t i v e r e s u l t s i n con- t r o l l i ng the a c t i v i t y o f c a r i e s . Pearlman c r i t i c i z e d f u r t h e r the safe- t y and p n c t i c a l i t y o f a d m i n i s t e r i n g f l u o r i d e i n m i l k . F l u o r i d e i s i n -

Pearlman,22 i n 1953, c r i t i c i z e d m i l k as a v e h i c l e f o r f l u o r i d e .

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troduced i n t o d r i n k i n g water by a d e v i c e f o r c o n s t a n t f e e d i n g which i s au tomat i ca l l y c o n t r o l l e d and requ i res minimum o f a t t e n t i o n and produces no danger o f a t o x i c c o n c e n t r a t i o n . I n a d a i r y , however, t h e chemical wou!d have t o be added t o i n d i v i d u a l v a t s o f m i l k , and g r e a t c a u t i o n w u l d be r e q u i r e d t o m a i n t a i n t h e c o n c e n t r a t i o n s as a c o n s t a n t . I f f l u o r i d a t e d m i l k were used, i t would be necessary t o r e g u l a t e the d i s - t r i b u t i o n so t h a t t he m i l k would n o t be sent i n t o areas where the water conta ined the o p t i m a l o r more than o p t i m a l amount o f f l u o r i d e . F luo- r i d a t e d water c o s t s , on the average, 8.8 cen ts per c a p i t a per year b u t i f the c o s t o f f l u o r i d a t e d m i l k were o n l y one f o u r t h o f a c e n t above the r e g u l a r p r i c e per q u a r t ( a low es t ima te ) i t would c o s t 90 cen ts per c a p i t a per year more than f l u o r i d a t e d water.

i n 1962, a f o u r - y e a r s t u d y o f 65 c h i l d r e n , a t t e n d i n g the Labora tory School o f Lou is iana S ta te U n i v e r s i t y , who r e c e i v e d d a i l y a h a l f p i n t o f f l u o r i d a t e d m i l k s u p p l y i n g sodium f l u o r i d e ( 1 mg.). D u r i n g t h e summer, t h e p a r e n t s added t h e same a- mount t o a g l a s s o f m i l k . A n o t h e r 64 c h i l d r e n f r o m a n o t h e r schoo l served as c o n t r o l s . The average o v e r - a l l percentage o f DMF t e e t h per c h i l d f o r a l l ages was 5.95 percent f o r the t r e a t e d group and 27.64 per- c e n t f o r the c o n t r o l s . The b e n e f i c i a l r e s u l t s ob ta ined i n t h i s s tudy , by the use o f f l u o r i d a t e d m i l k i n the p reven t ion o f d e n t a l c a r i e s , were r e p o r t e d t o be s i m i l a r t o pub1 ished r e p o r t s on the r e s u l t s o f f l u o r i - da ted water. There was a 70 pe rcen t r e d u c t i o n of the c a r i o u s l es ions .

B i b b ~ , ~ i n 1962, repo r ted t h a t exper iments w i t h r a d i o a c t i v e iso topes o f f l u o r i n e had shown t h a t when f l u o r i n e was added t o m i l k t h a t some f l u o r i n e d i d e n t e r t h e t e e t h , b u t t h a t t h e amount was l e s s than t h a t t aken up by t h e t e e t h f rom f l u o r i d e i n t h e water . There seems t o be no d i r e c t l a b o r a t o r y o r c l i n i c a l e v i d e n c e r e l a t i n g t o t h e up take o f f l u o r i n e f rom f r u i t j u i c e s .

E u s o f f and o t h e r s , 2 3 r e p o r t e d ,

Cremer , lo i n 1961, r e p o r t e d t h a t f l u o r i n e added t o t a b l e s a l t ( I 0 mg. o f sodium f l u o r i d e pe r 1.0 kg. o f s a l t ) has been s t u d i e d on a se- l e c t i v e b a s i s m a i n l y i n Sweden and S w i t z e r l a n d . He s t a t e d t h a t con- v i n c i n g ev idence o f t h e v a l u e o f f l u o r i d a t e d s a l t was l a c k i n g .

Ege,I3 i n 1962, recommended t h a t enr ichment of c e r e a l s w i t h f l u o r i d e be cons idered. I n Denmark, s t u d i e s had shown t h a t t he q u a n t i t y o f t o - t a l c e r e a l s consumed by i n d i v i d u a l s was s u r p r i s i n g l y c o n s t a n t i n r e l a - t i o n t o t h e t o t a l c a l o r i c i n take . i3y a n a l y z i n g the s tudy , "Danish I n - v e s t i g a t i o n s on Human Food I n t a k e " , the c o n c l u s i o n was reached t h a t i f 3.5 mg. o f f l u o r i n e were added t o each k i l o g r a m o f c e r e a l , 98 pe rcen t o f the popu la t i on would rece ive from 0.6 t o 1.5 mg. o f f l u o r i n e per day.

The Counc i l on Den ta l The rapeu t i cs o f t h e American Denta l Associa- t i o n ' , i n 1961, s t a t e d t h a t i t does n o t approve the a d d i t i o n o f f l u o - r i d e t o v i t a m i n s . V i t a m i n s have n o t been proved t o i nc rease t h e e f - f e c t i v e n e s s o f t h e f l u o r i d e i n r e d u c i n g t h e a c t i v i t i e s o f d e n t a l ca- r i e s . The q u a n t i t y o f admin i s te red f l u o r i d e has become a c r i t i c a l con- s i d e r a t i o n and i n ins tances i n wt i ch f l u o r i d e may occur i n the d r i n k i n g

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water , t h e f i x e d comb amins.

DISCUSSION

p r e s c r i b e r must l ower t h e amount o f f l u o r i d e , n a t i o n , wou ld a l s o reduce t h e amount o f admin

which, i n a s t e r e d v i t -

Al though 3 ibby and o t h e r s 4 repo r ted b e n e f i t s from f l u o r i d e lozenges, they l a t e r s t a t e d i n the same paper t h a t no p o s i t i v e conc lus ions cou ld be drawn because o f the s h o r t d u r a t i o n o f t h e i r s tudy ( 1 2 t o 14 months) and the smal l number o f p a t i e n t s . There was such a g r e a t l o s s o f c h i l d - ren f rom one group o f c o n t r o l s t h a t t h i s g roup was o m i t t e d . I n one i n s t i t u t i o n o f c h i l d r e n were examined by a d i f f e r e n t d e n t i s t . The c h i l d r e n were n o t examined r a d i o g r a p h i c a l l y . T h i s p rocedure would be v a l u a b l e i n a s t u d y o f such s h o r t d u r a t i o n . The d a t a were p resen ted as new c a r i o u s l e s i o n s p e r p a t i e n t ( 6 . 6 f o r t h e c h i l d r e n i n g e s t i n g

f l u o r i d e p i l l s ; 4.") f o r the c h i l d r e n chewing f l u o r i d e lozenges; and 6.7 f o r t h e c o n t r o l s ) . There was no i n d i c a t i o n t h a t t h e s e f i g u r e s were s t a t i s t i c a l l y s i g n i f i c a n t . The da ta were ob ta ined from a group o f i n - s t i t u t i o n a l i z e d c h i l d r e n and, hence, were n o t n e c e s s a r i l y rep resen ta - t i v e o f the t o t a l p o p u l a t i o n . There was no i n d i c a t i o n t h a t the c h i l d - ren, who chewed the lozenges, d i d n o t swal low them. I f the p i l l s were swallowed, the r e s u l t s m igh t be a t t r i b u t e d t o sys temic as w e l l as t o p i - c a l e f f e c t . T h i s research was completed i n 1945 b u t was n o t r e p o r t e d u n t i l 1955.

A rno ld and o t h e r s 4 s t a t e d t h a t t he ev idence o f t h e c a r i o s t a t i c e f - f e c t o f d a i l y consumpt ion o f f l u o r i d e t a b l e t s was p resumpt i ve , i nas - much as the d a t a c o u l d n o t be compared d i r e c t l y w i t h the d a t a ob ta ined f rom a group o f c o n t r o l s . A group o f 221 c h i l d r e n r e c e i v e d the tab - l e t s , b u t o n l y the records o f about h a l f were made a v a i l a b l e . For the f i r s t two years o f the s tudy , t he pa ren ts added concen t ra ted s o l u t i o n s o f sodium f l u o r i d e t o t h e d r i n k i n g water ( 1 ppm). T h i s method o f ad- m i n i s t r a t i o n was changed t o t h e d a i l y a d m i n i s t r a t i o n o f t a b l e t s , be- cause t a b l e t s were c o n s i d e r e d l e s s v a r i a D l e . The o e n e f i t s , i f any, t h e r e f o r e , shou ld n o t be a t t r i b u t e d t o the t a D l e t s a lone. T h i s s tudy presented some o f t he problems o f s a f e t y and p r a c t i c a l i t y . Parents had t o be cau t ioned t o analyze the home-supply o f water be fo re adding f l u o - r i d e s t o the d i e t . W r i t t e n i n s t r u c t i o n s and c a r e f u l e x p l a n a t i o n s were p rov ided f o r t h e p a r e n t s i n o r d e r t h a t t he amount, f requency , and ad- m i n i s t r a t i o n o f t h e t a b l e t s would be s tandard i zed . T h i s group o f pa- r e n t s c o n s i s t e d o f d e n t i s t s , phys i c ians , and p r o f e s s i o n a l employees o f t l : U n i t e d S t a t e s P u b l i c H e a l t h S e r v i c e and t h e members o f t he group were accepted as capab le o f f o l l o w i n g i n s t r u c t i o n s c o n s t a n t l y and ex- a c t l y . These p a r e n t s were n o t r e p r e s e n t a t i v e o f t he t o t a l p o p u l a t i o n s i n c e they were v e r y w e l l educated and p r o b a b l y m o t i v a t e d r e a d i l y t o p r o v i d e good d e n t a l h e a l t h f o r t h e i r c h i l d r e n . I n s p i t e o f t he favor - a b l e aspec ts o f t h e p a r e n t s concerned, o n l y one h a l f o f t h e f a m i l i e s c o n t i n u e d t o g i v e t a b l e t s t o t h e i r c h i l d r e n f o r t h e necessary number o f years. The c h i l d r e n ' s i n t a k e o f fe rmentab le carbohydra te cou ld have

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been eva lua ted as an i m p o r t a n t f a c t o r i n d e n t a l c a r i e s . The s t u d i e s o f D e r r o w l ' and B i x l e r 7 were p r e s e n t e d as papers , i n

1960, a t t h e mee t ing o f t h e I n t e r n a t i o n a l A s s o c i a t i o n f o r Den ta l Re- search i n Chicago, and t h e r e was no i n d i c a t i o n t h a t they have been pub- l i s h e d s ince t h a t t ime. The experiments; conducted w i t h bo th dogs and human beings, have shown, a f t e r i n g e s t i o n o f f l u o r i d e t a b l e t s , t h a t the f l u o r i d e i n t h e b l o o d was r a p i d l y c l e a r e d by t h e plasma and e x c r e t e d i n the u r ine . They reported, under such p h y s i o l o g i c c o n d i t i o n s , t h a t i t would seem imposs ib le t o m a i n t a i n those c o n d i t i o n s i n t h e b lood which must be p r e s e n t i n o r d e r t o have t h e optimum s u b s t i t u t i o n o f f l u o r i d e i n the deve lop ing t o o t h t o the e x t e n t requ i red f o r p roduc ing res i s tance t o d e n t a l c a r i e s . The t a b l e t s would n o t produce the s i t u a t i o n known t o occur when a c h i l d consumes d r i n k i n g water c o n t a i n i n g 1.0 ppm f l u o r i n e th roughout the day.

The evidence f o r the conc lus ions drawn by Feltman and Kosel14 scarce- l y was s u b s t a n t i a t e d by the d a t a presented. That an inc reased concen- t r a t i o n o f f l u o r i d e e x i s t e d i n b o t h t h e b lood o f t h e c o r d and i n t h e p l a c e n t a l t i s s u e o f t he women i n g e s t i n g f l u o r i d e s was s u b s t a n t i a t e d by t h e d a t a p resented . The r e s t o f t h e d a t a p resen ted d i d n o t c o r r e l a t e w i t h the conc lus ions o f the i n v e s t i g a t o r s . The da ta f o r suppor t i ng the c o n c l u s i o n s t h a t f l u o r i d e i n t h e f e t a l b lood a f f e c t e d t h e d e v e l o p i n g t e e t h by making them more r e s i s t a n t t o d e n t a l c a r i e s was presented i n t a b u l a r form. The i n v e s t i g a t o r s , however, d i d n o t ana lyze t h e i r data. The d a t a were presented as the average d e f and DMF r a t e s o f 618 s tudy "cases" compared t o 416 c o n t r o l s . The t a b l e was broken down i n t o 162 c h i l d r e n who rece ived f l u o r i d e s ( t y p e n o t i n d i c a t e d ) p r e n a t a l l y b u t n o t p o s t n a t a l l y , 288 c h i l d r e n who r e c e i v e d f l u o r i d e s p r e n a t a l l y and pos t - n a t a l l y and t h e 416 c o n t r o l s . Simple a d d i t i o n r e v e a l s t h a t t h e d a t a i nc luded o n l y 450 c h i l d r e n i n s t e a d o f t h e o r i g i n a l 618 c h i l d r e n . The i n v e s t i g a t o r s f a i l e d t o e x p l a i n t h i s i n c o n s i s t e n c y .

Fel tman and Kosel p resen ted no d a t a t o s u b s t a n t i a t e t h e s ta temen t t h a t f l u o r i d e s were D e n e f i c i a l o n l y when begun i n t h e f i r s t and second t r i m e s t e r o f pregnancy. The i n v e s t i g a t o r s d i d n o t r e p o r t t he t ype of f l u o r i d e t a b l e t t h a t p roduced " a d v e r s e " r e a c t i o n s i n t h e p a t i e n t s . They c o n t r o l l e d t h e t e s t f o r t h e f a c t o r o f t he b i n d e r b u t a p p a r e n t l y d i d n o t c o n t r o l f o r t h e f l u o r i d e s a l t a d m i n i s t e r e d . They f a i l e d t o i n d i c a t e t h e number o f p a t i e n t s h a v i n g "adve rse " r e a c t i o n s who were p r e g n a n t women r a t h e r than c h i l d r e n . I f most o f them were p regnan t women, t h e r e i s t h e p o s s i D i l i t y t h a t t h e r e a c t i o n s were caused by the comb ina t ion o f hormonal changes and t h e t a b l e t r a t h e r than the t a b l e t a lone. P h i l i p Jay s t a t e d ( i n a persona l i n t e r v i e w , Oct. 1962) t h a t he knew o f no c o n c l u s i v e ev idence t h a t suppor ted the theo ry t h a t supp le- mentary f l u o r i d e enab les pregnant women t o p r o t e c t t he t e e t h o f t h e i r unborn c h i l d r e n . He s t a t e d t h a t he had reviewed Feltman and Kosel .

The r e s u l t s o f K r u s i c l s l g s t u d y were based on a l i m i t e d number o f schoo l c h i l d r e n and have t o be regarded as i n c o n c l u s i v e evidence. The

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Counc i l on Denta l The rapeu t i cs has expressed the o p i n i o n t h a t f l u o r i d e from t a b l e t s c o n t a i n i n g c a l c i u m f l u o r i d e can n o t be c o n t r o l l e d accu- r a t e 1 y.

The s tudy by Ziemnorwica-GlowackaL3 r e p o r t e d D e n e f i c i a l e f f e c t s from the a d m i n i s t r a t i o n o f t a b l e t s o f sodium f l u o r i d e , b u t the r e s u l t s were n o t as b e n e f i c i a l as the i n g e s t i o n o f f l u o r i d a t e d water (60-70 pe rcen t r e d u c t i o n o f c a r i o u s l e s i o n s ) . Such a study needs t o be con t inued f o r more than t h r e e years i n o rde r t o e s t a b l i s h the e x t e n t t h a t f l u o r i d e i n t h e form o f inges ted t a D l e t s w i l l reduce c a r i o u s l e s i o n s .

The o p i n i o n expressed ~y t h e Counc i l o f Denta l T h e r a p e u t i c s o f the American Denta l A s s o c i a t i o n 2 and t h e Canadian Denta l A s s o c i a t i o n * was t h a t p recau t ions must be taken i n the d i s t r i b u t i o n o f any d i e t a r y sup- plements o f f l u o r i d e s . DudenDostle, Grissom and S te inbe rg12 completed an e x t e n s i v e survey and found t h a t a ve ry smal l percentage o f d e n t i s t s were f o l l o w i n g the C o u n c i l ' s recommended p r e c a u t i o n s f o r d i s t r i b u t i n g f l u o r i d e s . The s a f e t y o f such i n d i s c r i m i n a t e use o f f l u o r i d e s shou ld be cons ide red s e r i o u s l y .

i n 1952, c r i t i c i z e d t h e use o f m i l k as a v e h i c l e f o r f l u o r i d e . H i s c r i t i c i s m s , based on a r e v i e w o f t h e l i t e r a t u r e , were w e l l presented. Except f o r the f i r s t c r i t i c i s m , none have been ser ious- l y chal lenged.

Rusoff and o t h e r s 2 3 conducted a w e l l c o n t r o l l e d exper iment--use o f t h e b l i n d t e s t f o r t he c l i n i c a l and r a d i o g r a p h i c examina t ions and the use o f two d e n t i s t s t o c o n f i r m the d i a g n o s i s f o r each c h i l d . The da ta were analyzed s t a t i s t i c a l l y (use o f t he "t" t e s t t o de termine the l e v e l o f s t a t i s t i c a l s i g n i f i c a n c e ) . They de te rm ined t h a t t h e v a r i a t i o n i n inc rements o f new DMF t e e t h i n t h e group s t u d i e d ( c h i l d r e n i n g e s t i n g f l u o r i d a t e d m i l k ) when compared t o the c o n t r o l s was h i g h l y s i g n i f i c a n t . The d i f f e r e n c e s i n percentages o f DMF t e e t h per c h i l d (9-11 y e a r s ) o f t he group s t u d i e d and the c o n t r o l s were n o t s i g n i f i c a n t s t a t i s t i c a l l y . The d i f f e r e n c e between the va lues f o r the 12 yea r -o lds was s i g n i f i c a n t a t t he f i v e pe rcen t l e v e l o f p r o b a b i l i t y . They r e p o r t e d t h a t t he l ack of s t a t i s t i c a l s i g n i f i c a n c e was the r e s u l t , most l i k e l y , o f t h e smal l number o f c h i l d r e n i n each age-group. Since c l u s t e r samples were used ( c h i l d r e n from t h e U n i v e r s i t y School served as t h e exper imen ta l group and c h i l d r e n f rom t h e H i g h l a n d E lemen ta ry School s e r v e d as t h e con- t r o l s ) , t h e samples shou ld be s i m i l a r i n o r d e r t o p r o v i d e s i g n i f i c a n t da ta . They d i d n o t r e p o r t how f a m i l i a l backgrounds, e d u c a t i o n a l and f i n a n c i a l backgrounds were made s i m i l a r f o r bo th groups. They repo r ted t h a t no s p e c i a l d i e t s were p rov ided t o e i t h e r group. The d i e t s o f the c h i l d r e n shou ld have been s t u d i e d c a r e f u l l y , inasmuch as the number of c h i l d r e n was smal l and the d u r a t i o n of the s tudy sho r t . More research, hence, i s i nd i ca ted .

EgeI3 f a i l e d t o cons ide r t h a t the q u a n t i t y of t o t a l c e r e a l s migh t be cons tan t i n r e l a t i o n t o the t o t a l c a l o r i c in take , but, i f f l u o r i d e s were added t o ce rea ls , t h e amount o f f l u o r i n e t h a t each i n d i v i d u a l wou ld re - c e i v e would v a r y w i t h h i s c a l o r i c i n t a k e . Two y e a r - o l d s , w i t h t h e i r

_ -

Pearlman22,

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low c a l o r i c i n t a k e , most l i k e l y would need as much f l u o r i d e f o r t h e i r d e v e l o p i n g t e e t h as t h e e i g h t y e a r - o l d s , y e t t h e amount o f f l u o r i d e t h a t they doould r e c e i v e would be c o n s i d e r a b l y less. The same problems o f s a f e t y , p r a c t i c a l i t y , and d i s t r i b u t i o n would e x i s t w i t h f l u o r i d a t e d c e r e a l s as e x i s t f o r f l u o r i d a t e d mi lk . These problems must a l s o be con- s ide red i n any e v a l u a t i o n o f the f l u o r i d a t i o n o f t a b l e s a l t and v i tamins .

SUMMARY

This r e p o r t has presented the f i n d i n g s o f an appra i sa l o f the l i t e r a -

t u r e on t h e s u p p l e m e n t a t i o n o f t h e d i e t w i t h f l u o r i d e s . The s t u d i e s t h a t have been reviewed on the d i e t a r y supp lementa t ion o f f l u o r i d e s by i n g e s t i n g t a b l e t s i n d i c a t e a p o s s i b i l i t y o f a r e d u c t i o n o f c a r i o u s l e - s ions . The s t u d i e s have been o f s h o r t d u r a t i o n , lacked c o n t r o l s , used sma l l groups o f s u b j e c t s , o r lacked a randomized sample. S t a t i s t i c a l a n a l y s i s o f t e n was n o t c a r r i e d o u t i n t h e s t u d i e s repo r ted . The pro- blems o f t he p r a c t i c a l i t y , t he s a f e t y , and t h e d i s t r i b u t i o n o f t a b l e t s o f f l u o r i d e were presented.

A recen t study o f f o u r years d u r a t i o n i n d i c a t e d t h a t 65 c h i l d r e n i n - g e s t i n g f l u o r i d a t e d m i l k may have had as much r e d u c t i o n as 70 pe rcen t o f c a r i o u s les ions . A l ack o f s t a t i s t i c a l s i g n i f i c a n c e was repo r ted be- cause o f the smal l number o f c h i l d r e n i n each age group. The rev iew o f t h e l i t e r a t u r e p resen ted no s o l u t i o n s f o r t h e problems o f t h e sa fe ty , p r a c t i c a l i t y , and t h e d i s t r i b u t i o n o f f l u o r i d a t e d m i l k . None o f t h e s t u d i e s reviewed p rov ided c o n v i n c i n g evidence o f t he va lue o r the prac- t i c a l i t y o f f l u o r i d a t i n g t a b l e - s a l t , f r u i t j u i c e s , v i t am ins , o r ce rea l .

Cont inued research on the va r ious methods o f a d m i n i s t e r i n g f l u o r i d e s i s i n d i c a t e d . I f t h e i r e f f e c t i v e n e s s , p r a c t i c a l i t y and s a f e t y o r ap- p l i c a t i o n can be demonstrated, they may become v a l u a b l e i n a r e a s where i t i s imposs ib le t o f l u o r i d a t e t h e communal water.

CONCLUSIONS

1 . The s t u d i e s repo r ted have i n d i c a t e d t h a t f l u o r i d e s inges ted as tab- l e t s may have c a r i o s t a t i c e f f e c t s b u t the b e n e f i t s have n o t beem estab- 1 i shed s u f f i c i e n t l y t o show t h a t they a r e as g r e a t as those rece i ved f r o m d r i n k i n g f l u o r i d a t e d water .

2. The s t u d i e s o f t h e a d d i t i o n o f f l u o r i d e s t o m i l k have n o t es tab - l i s h e d beyond doubt t h a t t h i s p rocedure w i l l reduce c a r i o u s l e s i o n s as much as 70 percent.

3. No conc lus i ve evidence has been submi t ted t o e s t a b l i s h b e n e f i t s from t h e a d d i t i o n o f f l u o r i d e s t o s a l t , c e r e a l , v i t a m i n s , o r f r u i t - j u i c e .

4. F l u o r i d a t i o n o f m i l k , ce rea l , f r u i t - j u i c e , t a b l e - s a l t , v i t am ins and t a b l e t s p resents problems of sa fe ty , d i s t r i b u t i o n and p r a c t i c a l i t y t h a t must be so lved b e f o r e ex tens i ve use can be recommended.

M r s . M o n t g o m e r y l i v e s a t 1 2 1 0 H e n r y S t r e e t , A n n A r b o r , M i c h i g a n .

207

B I B L I O G R A P H Y

I .

2 .

3 -

4 .

5 .

6 .

7

8

10.

11.

1 2 .

13.

14.

15.

1 6 .

1 7 -

1 8 .

1 9 .

20.

2 1 .

2 2 .

23.

2 4 .

2 5 .

A m e r i c a n D e n t a 1 A S S O C i a t i o n , C o u n c i 1 o n D e n t a I T h e r a p e u t l c s . A m e r i c a n D e n t a l A s s o c i a t i o n l i s t s d i e t a r y f l u o r i d e s u p p l e m e n t s i n g r o u p D . A m . D e n t . A . J . , 6 ~ : 2 8 0 , F e b . 1 9 6 2 .

---------- . P r e s c r i b i n g s u p p \ e m e n t s o f d i e t a r y f l u o r i d e s . A m . D e n t . A . J . , 5 6 : 5 8 9 - 9 1 , A p r . 1 9 5 8 . A l t e r n a t i v e s t o w a t e r f l u o r i d a t i o n . 3 a n a d . D e n t . A . J . , 2 7 : 5 2 2 - 4 , O c t . 1 9 6 1 .

A r n o l d , F . A . , J r . , e t a \ . S o d i u m f l u o r i d e t a b l e t s f o r c h i l d r e n . D e n t . P r o g r e s s , 1:8-12, O c t . 1 9 6 0 .

B i b b y , B . G . M i l k o r f r u i t j u i c e a s a v e h i c l e f o r f l u o r l n e . A m . M e d . A . J . , 1 7 9 : 9 5 , O c t . 7 , 1 9 6 1 .

B i b b y , 8 . G . , W i I k l n s , E s t h e r , a n d W i t o l , E v e l y n . A p r e l i m i n a r y s t u d y o f t h e e f f e c t s o f f l u o r i d e l o z e n g e s a n d pills o n d e n t a l

c a r i e s . O r a l S u r g . , O r a l M e d . a n d O r a l P a t h . , 8 : 2 1 3 - 6 , M a y 1 9 5 5 . B i x l e r , D a v i d . B l o o d a n d u r i n a r y s t u d i e s u s i n g f l u o r i d e t a b l e t s . A b s t r . J . D e n t . R e s . , 3 9 : 1 1 9 , N o v . - D e c . 1 9 6 0 -

C a n a d i a n D e n t a l A s s o c i a t i o n , C o u n c i l o n R e s e a r c h . S e l f - a d m i n i s - t r a t i o n o f f l u o r i d e s . C a n a d . D e n t . A . J . , 2 7 : 1 6 7 , M a r . 1 9 6 1 .

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C r e m e r , H . D . F l u o r i n e d o s a g e s . D e n t . A b s t r . , 6 : 1 1 6 , F e b . 1 9 6 1 . D e r r o w , D . E . F l u o r l d e a v a i l a b i l i t y f r o m f l u o r i d e t a b l e t s . A b s t r . J . D e n t . R e s . , 3 9 : 7 0 5 , J u l y - ~ u g . 1 9 6 0 .

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E g e , R i c h a r d . E n r i c h m e n t o f c e r e a l s w i t h f l u o r i n e . D e n t . A b s t r . , 7 : 9 3 - 4 , F e b . 1 9 6 2 .

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---------- . P r e n a t a l a n d p o s t n a t a l i n g e s t i o n o f f l u o r i d e s ; f o u r - t e e n y e a r s o f i n v e s t i g a t i o n ; f i n a l r e p o r t . J . D e n t . M e d . , 1 6 :

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S t a t e m e n t s o n p r o p o s e d a l t e r n a t i v e s t o f l u o r i d a t i o n o f w a t e r s u p - p l i e s . P u b . H e a l t h R e p . , 7 4 : 5 1 1 - 2 0 , J u n e 1 9 5 9 .

Z i e m n o r w i c z - G l o w a c k a , W a n d a . S o d i u m f l u o r i d e t a b l e t s a s a m e a n s t o r e d u c e t h e i n c i d e n c e o f c a r i e s i n k i n d e r g a r t e n p u p i l s . D e n t . A b s t r . , 6 : 3 9 7 - 8 , J u l y 1 9 6 1 .

237 1 9 5 5 .

1 9 0 - 9 , O c t . 1 9 6 1 .