Australian Dental Journal, June, 1975
170
SIX years of fluoridation on the goldfields of Western Australia 0. W. Medcalf, B.D.Sc. Dental Health Education Oflicer, Dental Health Service Public Health Department of Western Australia
ABSTRACT-T~~ Kalgoorlie-Boulder-Kambalda area in arid inland Western Australia receives its water supply from distant Perth, through a pipeline constructed in the fabulous goldrush period at the turn of the century. This water was fluoridated at the source in 1%8. Comparison of dental data obtained by examination of goldfields schoolchildren before and after 6 years of fluoridation shows improved dental health through reduced caries rates, less tooth loss, and a change in the pattern of child dental care. (Received for publication July. 1974)
Introduction Residents of the Western Australian goldfields receive their drinking water by pipeline from a dam in the Darling Ranges, 370 miles away. Prior to 1%8, this water, which is obtained by surface catchment, contained 0.1 to 0.2 milligrams of fluoride per litre. Fluoridation of the goldfields water supply commenced in January 1968, using sodium silicofluoride and gravimetric dry feed equipment at the dam site. During the first three years, the recommended fluoride level was 0.7 ppm during the This survey was conducted by the Public Health Depactment of Western Australia under the direction of the Commissioner of Public Health, Dr W. S. Davidson. Permission to publish is acknowledged. The assistance of Dr M. Lugg, Health Statistician, Department of Pubhc Health, Western Australia is also acknow-
ledped.
summer months (October to March) and 0.9 ppm from April to September. This seasonal variation was discontinued as from 1st October, 1971, in favour of a constant level of 0.9 ppm. The study was carried out to assess the effect of six years of fluoridation of the goldfields water supply on the dental health of selected age groups of goldfields school children. Examinations were carried out by the author. Method In December 1967, prior to fluoridation, a group of goldfields children who had never used fluoride supplement was examined'. In December 1
Medcalf, G. W.-Report on caries experience and treatment needs in Western Australian children aged 6-14 years. Auslral. D.J., 15:l. 50-54 (Feb.) 1970.
TABLE 1
Comparison of .the dentition of the children on the goldfields of Western Australia before and after six years of fluoridation
1967 (PRE-FLUORIDD Deciduous teeth
Permanent teeth ar th
Age
Me8n teeth
Mean DMF teeth
1.37 3.13 3.66 4.08 6.66
4.6 9.0 11.6 14.8 16.7
cgfd
cE;d
First Missing first
molars
No.
0 9 8 7
6 7 8 9 10
mo!Fs requiring extraction
Per chid No.
-
-
Teeth filled
Per child No.
Mean df teeth teeth C K I
c3h
Per child
Missing first and sccond molars Itotal) No.
Teeth
requiring extraction
Per chi'd No,
Teeth filled
Per chi,d No.
Children Questionable Number fluorosisof with carbs no exurience children
Per chid
~
39
64
1 .016 .26 5 .20 11 .49 22
1 15 16 32
.01 3 - 23 28 .14 61 .33 72
.*
.03 .38 .49 .77 1.1
16 6.25 11.9 5.36 8.4 4.38
140 112 167
1.38 1.86 2.92
90 50 22
.89
33 .38
23
23 33
.22
.38 S7
-2
-
~
2
1973 Reduction in DMF teeth p r child ( p r cent)
Age when fluoridation beam
(months)
7 6
6 7 8 9 10
M
64
3
1-12 13-24 25-36 3748 49-60
4.4 8.7 11.4 14.3 17.3
0.94 2.33 2.73 3.72 5.48
31.4 25.6 25.4 8.8 17.7
I1
.02
-2
.03
4 2 9 22
-
-
.08 .18
Rediiction in df teeth per child laer cent)
- 2 .02 14 .09 16 .06 82 .19 125
A1
17
7 23
.016
17.3 3.74 13.5 4.53 10.3 4.12
.I1
.14 .74 1.02
30 115 179
40.2 15 5 5.9
.23 41 .93 59 1.56 52
.32 44 .48 110 .45 105
.34 .89 .91
14 4 3 4 1 26
10 5
2 3 1
21
I72 1973, children who had lived on the goldfields water supply system since fluoridation and who had no history of fluoride supplementation either before or after 1967 were examined. The Type 2 limited examination (clinical only), as defined by the Special Commission on Oral and Dental Statistics of the Federation Dentaire Internationale, was used in each survey.
Australian Dental Journal, June, 1975 criteria used for “requiring extraction” were: “Less than half the crown remaining”, or “obvious pulp involvement”. In the deciduous dentition, the reduced tooth loss is even more marked. In the 6 to 7-year-old
TABLE 2
A comparison of children aged six, seven and eighi years before and after fluoridation
Results and discussion A comparison of the dental condition of the two groups of children is made in Table 1. None of the 1973 group has had lifetime exposure to fluoridation. The 6-year-old group, born during 1967, were all less than 1 year old when fluoridation began. Those aged 7 were between 1 and 2 years of age and the 8-year-olds were all over 2 years, at which age their deciduous dentition may be considered fully erupted. In the permanent teeth, the 1973 group shows a reduction in DMF teeth per child ranging from 31 per cent in 6-year-olds to 9 per cent in 9-yearolds. In the deciduous dentition, the index of df teeth per child has been reduced by 40 per cent for 6-year-olds, 16 per cent for age 7, and 6 per cent for the 8-year-old group. This pattern of reduction in caries prevalence is similar to that shown in other fluoridated areas where the duration of fluoridation has been similar, although the magnitude of the reduction in permanent teeth is not as greatz, 3 . * # 6 . 8. This is presumed t o be due to the low average level in the first three and one-half years.
Tooth loss: In 1967 there were 17.7 missing first permanent molars per 100 children aged 6-10 years. In the same age group in 1973, the rate was 6.1 missing first permanent molars per 100 children ( x z 11.28, p = .001). In addition, the number of first permanent molars requiring extraction had dropped from 10.8 per 100 children to 7.1 per 100 children ( x 2 8.95, p = .01). The
F. A.. Jay. P., and Knutson, J. W.Studies on mass control of dental caries through fluoridation of the public water supply. U.S. Public Health Service publication No. 825, 1962 (pp. 198-200). 3 Arno!d. F. A., Dean, H. T . , and Knutson, J. W.-Effect of fluoridated Public Water supplies on dental caries prevalence. 7th year of Grand Rapids Muskegon study. U.S. Public Health Service publication No. 825, 1962 (PP. 2W206). 4 Russel, A,, L . , and Carl L. While-Dental caries in Maryland children after 5 years of fluoridation. U.S. Public Health Service publication No. 825. 1962 (pp. 245-250). 5 Russel, A. L., and Carl L. White-Dental caries in Maryland children after 7 years of fluoridation. U.S. Public Health Service publication No. 825, 1962 (pp. 25.0-253). 8 Ludwig T O.-The Hastings fluoridation propct 111. Denial ekects between 1954 and 1961. New Zealand D.J., 58:271, 22-24 (Jan.) 1962. 2 Dean, H . T . , Arnold,
Deciduous teeth
- f:df ratio
No. of children
Age
Filled teeth per child
df teeth per child
ratio f:df teeth per child
1967
101 60 57
6 7 8
.22 .38 .57
6.25 5.36 4.38
.035 .070 .13
129 123 115
6
1973
7 8
.34 .89 .91
3.74 4.53 4.12
.091 .196 .221
TABLE 3
A comparison of the ratio of decayed surfaces to decayed teeth in children aged six and seven years before and after fluoridation (deciduous teeth)
1967 1973
Decayed teeth per child
Decayed surfaces per child
Ratio ds:d teeth p e r child
6 7
6.03 5.05
10.00 9.40
1.66 1.86
6 7
3.40 3.62
4.77 5.41
1.40 1.49
No. of children
Age
101 60 129 123
group, the number of missing first and second deciduous molars had fallen from 156 per 100 children in 1%7 to 58 per 100 children in 1973. It is reasonable to assume that missing first and second deciduous molars in this age group have been extracted due to caries. As a result of this reduction in extracted teeth, children aged 6, 7, and 8 in 1973 have one more tooth per child than children of the same age in 1967. During the same period, the number of deciduous teeth requiring extraction in the 6 to 7 age group fell from 87 per 100 children to 40 per 100 children. Conservative treatment: Another indication of the improvement in dental health is the change in the ratio of filled deciduous teeth to decayed plus filled deciduous teeth, as shown in Table 2. In the 6 to 8-year-old group, this ratio has doubled during the period of fluoridation. There has been no change in the dentist/population ratio on the goldfields during the 6-year period. It is clear
173
Australian Dental Journal, June, 1975 that dental care for the 6, 7, and 8-year-old children has become more conservative since fluoridation began.
Proximal surfaces: The preferential protection that fluoridation gives to the proximal surfaces is evident in the improved ratio of decayed surfaces to decayed teeth in the deciduous dentition of 6 and 7-year-old children (Table 3). The ratio has changed from 1.66 to 1.40 in 6-year-olds, and from 1.86 to 1.49 in 7-year-olds. Caries free children: The number of children aged 6-10 completely free from caries and with a full complement of teeth has increased from .55 per 100 children in 1%7 to 4.32 per 100 children in 1973 ( x 2 9.74, p = .01). Fluorosis: No cases of unacceptable dental fluorosis were seen. Ten children aged 6 years
showed white flecking of first permanent molar cusps and in other age groups a similar effect was seen on the newly-erupted teeth of a few individuals as shown in Table 1. In all cases, the classification was “questionable” or “very mild” on Dean’s scale. Conclusion After six years of fluoridation on the goldfields of Western Australia, the benefit to dental health is becoming apparent in the younger age groups of school children. The 6,7, and &year-old groups are dentally healthier than the same age groups of six years ago because they have more sound teeth, fewer missing teeth, fewer decayed teeth, and more of their decayed deciduous teeth have been filled. Dental Health Service Department of Public Health Box 265, P.O..West Perth, W.A. 6005
Rickets In the industrialized countries the incidence of rickets began to decline early in the twentieth century, although a few mild cases are still seen occasionally in most large cities. In a few parts of the world, however, rickets is still considered a major problem in child health. The disease has been reported as not uncommon in many parts of Asia and Africa. It is difficult to interpret some of these reports because the criteria for diagnosing mild cases are not well established. But the presence of even a few mild cases in a Rickets community serves as a warning against relaxation of the preventive measures persists today for two reasons. In northern cities the amount of sunlight, esrxcially during the long dark winters, is just barely adequate. In sunny parts of the world, it is often customary to keep infants and young children swaddled or indoors, which means they are not sufficiently exposed to the ultraviolet rays. While in theory a dietary supply of vitamin D appears to be unessential, in practice it is wise in countries far away from the equator to try to make sure that all infants and young children receive some vitamin from the diet. This also is true for communities where custom and habit prevent the exposure of children to sunlight.-WHO Chronicle, February, 1975.
...
170
SIX years of fluoridation on the goldfields of Western Australia 0. W. Medcalf, B.D.Sc. Dental Health Education Oflicer, Dental Health Service Public Health Department of Western Australia
ABSTRACT-T~~ Kalgoorlie-Boulder-Kambalda area in arid inland Western Australia receives its water supply from distant Perth, through a pipeline constructed in the fabulous goldrush period at the turn of the century. This water was fluoridated at the source in 1%8. Comparison of dental data obtained by examination of goldfields schoolchildren before and after 6 years of fluoridation shows improved dental health through reduced caries rates, less tooth loss, and a change in the pattern of child dental care. (Received for publication July. 1974)
Introduction Residents of the Western Australian goldfields receive their drinking water by pipeline from a dam in the Darling Ranges, 370 miles away. Prior to 1%8, this water, which is obtained by surface catchment, contained 0.1 to 0.2 milligrams of fluoride per litre. Fluoridation of the goldfields water supply commenced in January 1968, using sodium silicofluoride and gravimetric dry feed equipment at the dam site. During the first three years, the recommended fluoride level was 0.7 ppm during the This survey was conducted by the Public Health Depactment of Western Australia under the direction of the Commissioner of Public Health, Dr W. S. Davidson. Permission to publish is acknowledged. The assistance of Dr M. Lugg, Health Statistician, Department of Pubhc Health, Western Australia is also acknow-
ledped.
summer months (October to March) and 0.9 ppm from April to September. This seasonal variation was discontinued as from 1st October, 1971, in favour of a constant level of 0.9 ppm. The study was carried out to assess the effect of six years of fluoridation of the goldfields water supply on the dental health of selected age groups of goldfields school children. Examinations were carried out by the author. Method In December 1967, prior to fluoridation, a group of goldfields children who had never used fluoride supplement was examined'. In December 1
Medcalf, G. W.-Report on caries experience and treatment needs in Western Australian children aged 6-14 years. Auslral. D.J., 15:l. 50-54 (Feb.) 1970.
TABLE 1
Comparison of .the dentition of the children on the goldfields of Western Australia before and after six years of fluoridation
1967 (PRE-FLUORIDD Deciduous teeth
Permanent teeth ar th
Age
Me8n teeth
Mean DMF teeth
1.37 3.13 3.66 4.08 6.66
4.6 9.0 11.6 14.8 16.7
cgfd
cE;d
First Missing first
molars
No.
0 9 8 7
6 7 8 9 10
mo!Fs requiring extraction
Per chid No.
-
-
Teeth filled
Per child No.
Mean df teeth teeth C K I
c3h
Per child
Missing first and sccond molars Itotal) No.
Teeth
requiring extraction
Per chi'd No,
Teeth filled
Per chi,d No.
Children Questionable Number fluorosisof with carbs no exurience children
Per chid
~
39
64
1 .016 .26 5 .20 11 .49 22
1 15 16 32
.01 3 - 23 28 .14 61 .33 72
.*
.03 .38 .49 .77 1.1
16 6.25 11.9 5.36 8.4 4.38
140 112 167
1.38 1.86 2.92
90 50 22
.89
33 .38
23
23 33
.22
.38 S7
-2
-
~
2
1973 Reduction in DMF teeth p r child ( p r cent)
Age when fluoridation beam
(months)
7 6
6 7 8 9 10
M
64
3
1-12 13-24 25-36 3748 49-60
4.4 8.7 11.4 14.3 17.3
0.94 2.33 2.73 3.72 5.48
31.4 25.6 25.4 8.8 17.7
I1
.02
-2
.03
4 2 9 22
-
-
.08 .18
Rediiction in df teeth per child laer cent)
- 2 .02 14 .09 16 .06 82 .19 125
A1
17
7 23
.016
17.3 3.74 13.5 4.53 10.3 4.12
.I1
.14 .74 1.02
30 115 179
40.2 15 5 5.9
.23 41 .93 59 1.56 52
.32 44 .48 110 .45 105
.34 .89 .91
14 4 3 4 1 26
10 5
2 3 1
21
I72 1973, children who had lived on the goldfields water supply system since fluoridation and who had no history of fluoride supplementation either before or after 1967 were examined. The Type 2 limited examination (clinical only), as defined by the Special Commission on Oral and Dental Statistics of the Federation Dentaire Internationale, was used in each survey.
Australian Dental Journal, June, 1975 criteria used for “requiring extraction” were: “Less than half the crown remaining”, or “obvious pulp involvement”. In the deciduous dentition, the reduced tooth loss is even more marked. In the 6 to 7-year-old
TABLE 2
A comparison of children aged six, seven and eighi years before and after fluoridation
Results and discussion A comparison of the dental condition of the two groups of children is made in Table 1. None of the 1973 group has had lifetime exposure to fluoridation. The 6-year-old group, born during 1967, were all less than 1 year old when fluoridation began. Those aged 7 were between 1 and 2 years of age and the 8-year-olds were all over 2 years, at which age their deciduous dentition may be considered fully erupted. In the permanent teeth, the 1973 group shows a reduction in DMF teeth per child ranging from 31 per cent in 6-year-olds to 9 per cent in 9-yearolds. In the deciduous dentition, the index of df teeth per child has been reduced by 40 per cent for 6-year-olds, 16 per cent for age 7, and 6 per cent for the 8-year-old group. This pattern of reduction in caries prevalence is similar to that shown in other fluoridated areas where the duration of fluoridation has been similar, although the magnitude of the reduction in permanent teeth is not as greatz, 3 . * # 6 . 8. This is presumed t o be due to the low average level in the first three and one-half years.
Tooth loss: In 1967 there were 17.7 missing first permanent molars per 100 children aged 6-10 years. In the same age group in 1973, the rate was 6.1 missing first permanent molars per 100 children ( x z 11.28, p = .001). In addition, the number of first permanent molars requiring extraction had dropped from 10.8 per 100 children to 7.1 per 100 children ( x 2 8.95, p = .01). The
F. A.. Jay. P., and Knutson, J. W.Studies on mass control of dental caries through fluoridation of the public water supply. U.S. Public Health Service publication No. 825, 1962 (pp. 198-200). 3 Arno!d. F. A., Dean, H. T . , and Knutson, J. W.-Effect of fluoridated Public Water supplies on dental caries prevalence. 7th year of Grand Rapids Muskegon study. U.S. Public Health Service publication No. 825, 1962 (PP. 2W206). 4 Russel, A,, L . , and Carl L. While-Dental caries in Maryland children after 5 years of fluoridation. U.S. Public Health Service publication No. 825. 1962 (pp. 245-250). 5 Russel, A. L., and Carl L. White-Dental caries in Maryland children after 7 years of fluoridation. U.S. Public Health Service publication No. 825, 1962 (pp. 25.0-253). 8 Ludwig T O.-The Hastings fluoridation propct 111. Denial ekects between 1954 and 1961. New Zealand D.J., 58:271, 22-24 (Jan.) 1962. 2 Dean, H . T . , Arnold,
Deciduous teeth
- f:df ratio
No. of children
Age
Filled teeth per child
df teeth per child
ratio f:df teeth per child
1967
101 60 57
6 7 8
.22 .38 .57
6.25 5.36 4.38
.035 .070 .13
129 123 115
6
1973
7 8
.34 .89 .91
3.74 4.53 4.12
.091 .196 .221
TABLE 3
A comparison of the ratio of decayed surfaces to decayed teeth in children aged six and seven years before and after fluoridation (deciduous teeth)
1967 1973
Decayed teeth per child
Decayed surfaces per child
Ratio ds:d teeth p e r child
6 7
6.03 5.05
10.00 9.40
1.66 1.86
6 7
3.40 3.62
4.77 5.41
1.40 1.49
No. of children
Age
101 60 129 123
group, the number of missing first and second deciduous molars had fallen from 156 per 100 children in 1%7 to 58 per 100 children in 1973. It is reasonable to assume that missing first and second deciduous molars in this age group have been extracted due to caries. As a result of this reduction in extracted teeth, children aged 6, 7, and 8 in 1973 have one more tooth per child than children of the same age in 1967. During the same period, the number of deciduous teeth requiring extraction in the 6 to 7 age group fell from 87 per 100 children to 40 per 100 children. Conservative treatment: Another indication of the improvement in dental health is the change in the ratio of filled deciduous teeth to decayed plus filled deciduous teeth, as shown in Table 2. In the 6 to 8-year-old group, this ratio has doubled during the period of fluoridation. There has been no change in the dentist/population ratio on the goldfields during the 6-year period. It is clear
173
Australian Dental Journal, June, 1975 that dental care for the 6, 7, and 8-year-old children has become more conservative since fluoridation began.
Proximal surfaces: The preferential protection that fluoridation gives to the proximal surfaces is evident in the improved ratio of decayed surfaces to decayed teeth in the deciduous dentition of 6 and 7-year-old children (Table 3). The ratio has changed from 1.66 to 1.40 in 6-year-olds, and from 1.86 to 1.49 in 7-year-olds. Caries free children: The number of children aged 6-10 completely free from caries and with a full complement of teeth has increased from .55 per 100 children in 1%7 to 4.32 per 100 children in 1973 ( x 2 9.74, p = .01). Fluorosis: No cases of unacceptable dental fluorosis were seen. Ten children aged 6 years
showed white flecking of first permanent molar cusps and in other age groups a similar effect was seen on the newly-erupted teeth of a few individuals as shown in Table 1. In all cases, the classification was “questionable” or “very mild” on Dean’s scale. Conclusion After six years of fluoridation on the goldfields of Western Australia, the benefit to dental health is becoming apparent in the younger age groups of school children. The 6,7, and &year-old groups are dentally healthier than the same age groups of six years ago because they have more sound teeth, fewer missing teeth, fewer decayed teeth, and more of their decayed deciduous teeth have been filled. Dental Health Service Department of Public Health Box 265, P.O..West Perth, W.A. 6005
Rickets In the industrialized countries the incidence of rickets began to decline early in the twentieth century, although a few mild cases are still seen occasionally in most large cities. In a few parts of the world, however, rickets is still considered a major problem in child health. The disease has been reported as not uncommon in many parts of Asia and Africa. It is difficult to interpret some of these reports because the criteria for diagnosing mild cases are not well established. But the presence of even a few mild cases in a Rickets community serves as a warning against relaxation of the preventive measures persists today for two reasons. In northern cities the amount of sunlight, esrxcially during the long dark winters, is just barely adequate. In sunny parts of the world, it is often customary to keep infants and young children swaddled or indoors, which means they are not sufficiently exposed to the ultraviolet rays. While in theory a dietary supply of vitamin D appears to be unessential, in practice it is wise in countries far away from the equator to try to make sure that all infants and young children receive some vitamin from the diet. This also is true for communities where custom and habit prevent the exposure of children to sunlight.-WHO Chronicle, February, 1975.
...
