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The prevalence of dental caries in 5 and 15-year-old hereford children
PubL Hhh, Lond. ('1978) 92, .125:-130
The Prevalence ,of:Dental Caries in 5 and 15-year-old Hereford Children R: J. izon B.D.S.. D.D.P.H.R.C.S.
R. C: ,Pullen* B.D.S.
and G. A. Scivier .B,D,S., D.D.H,. D~D.P.H.R.C.S.
Hereford and 'Worcester Area Health ,4 uthority, Bedwardine House, Upper Wick Lane, Rushwick, Worcester
The survey involved the dental examination o f a random sample of 273 5-year-old chi'idren and 282 15-year.,old :children attending schools withira the City of Hereford. The results reveal a high prevalence of dental caries, a geographical variation .within the city, and a high percentage of affected teeth which are actively decaying. The community's possible 'response to the problem is discussed.
Introduction The purpose of" this survey was to investigate the prevalence of dental caries in 5 and 15-year-old children in Hereford, and to transform intb meaningful statistical figures the situation that the practising dentist sees in a clinical setting. In Short, it hopefully answers the question " H o w bad are children's teeth in Hereford ?" Instead o f the reply "Pretty b a d " or "'Not very g o o d , , which are comments based on that individual's clinical opinion o f a specific section o f the community and which in truth mean very little, one can now produce statements o f much greater detai:l wit'h correspondingly greater confidence. Providing the same diagnostic criteria and the conduct o f the examinations are,rigorously adhered ,to, it 'will be possible t o compare future 5 and 15-year-olds with their present-day counterparts. It is hoped that fluoridation will soon be introduced in Hereford, and the existence o'f reliable base-line ,data will thus allow comparisons to be made of future alterations in the level o f dental caries.
Subjects Two age groups were chosen, those aged 5 and 15 on 31 March 1977. Theadvantages o f 5-year-old children are that they are easily accessible, being in their first year of primary schoOl, in that they provide .a measure of decay for deciduous teeth and thirdly that any marked reduction in the level o f dental .caries due .to fluoridation will first be reflected in the younger age groups. The advantages o f choosing 15-year-olds for the survey are that they .too are easily accessible for sampling, being in their .last full y e a r o f school life and that information concerning the permanent dentition can b e ascertained without the complications of deciduous teeth being present, as one would have with, say, 12-year-olds. *Also at: New House, Garway Hill, Hereford. 0038-3506/78/920.3-0125 S01.O0/0
© 1978 The Society of Communily Medicine
126
R. J. lzon; R. C. Pullen and G. A. ~civier
~?ive-year-olds There are 13 schools within the city :that :provide education for 5-year-olds. Rather than have ,to disturb all these schools, it was decided to take a random sample o f six. The I3 schools were weighted according to their number o f 5-year-old .pupils, and using random number tables, the following six schools were selected: All Saints' Parochial Infants School Hunderton Infants School Our Lady's Roman Catholic Primary School St James' Church of England Infants School St Paul's Church of England Primary School Trinity Primary School The head teachers were approached and willingly gave their consent to the survey. Lists o f "children aged between 5 and 6 on 31 March 1977 were obtained from each o f the six schools. These children were arranged alphabetically and three out o f every four were sampled-a total o f 304. Two hundred and seventy-three 5-year-old children with a n average age of 5 years 6 months (and 10,days) were eventually examined. This was 9 0 ~ of those sampled, the remainder having moved o r been absent :through illness, and represented about 33 ~ of all 5-year-old children in the city. Fifteen-year-olds There are four maintained schools within the city providing education for 15-year-olds. Aylestone School Bishop of Hereford's Bluecoat School Haywood High School Whitecross School The head teachers were approached and all willingly gave their consent to the survey. One headmaster requested that a letter be sent tO the parents of all children who were sampled to tffke part. This was done, and we h a d n o refusals for examination. Lists ofchiidren aged between 15 and 16 on 31 March 1977 were obtained from each of the four schools. These children were ,arranged alphabetically and two out of every five were sampled--a total of 328. Two hundred and eighty-two 15-year-old children with an average age of 15 years 6 months(and 3 days)were eventually examined. This was 8 6 ~ of those sampled, and represented about 34 Yo of all 15-year-old children in the city. The last .week in March was chosen f o r the clinical examinations. Besides being :roughly the mid-point of the academic year, absenteeism was thought to be lower, certainly than the main winter months, and one did not encroach upon the summer term with its ,more interesting pursuits, not to mention examinations. Calibration The results and consequences o f epidemiological studies are invalid unless the methods of data collection are standardized and the criteria for identifying the conditions are Clearly defined and reproducible. A pre-pilot, pilot, calibration ,and :reproducibility studies were hdd for the three examiners and their respective recorders. We were thus able t o assess and to keep inter-and intra- examiner variability within acceptable statistical limits. The Clinical Examination The children were examined in the chair of a mobile dental unit. Illumination was by means o f a .60 W bulb in an Angtepoise lamp. Plane No. 4 disposable mirrors and probes were used, ~he probes being of a type with replaceable points and changed after every 10 examinations.
Dental caries in Hereford children
127
The diagnostic criteria and surface codes were as follows:
COdes 0 Sound 1 2
Unerupted Extracted
(ortho) 4
Decayed
5
Decayed (unrestorabte)
6
Missing
7
Filled
8
Filled and carious Traumatized
9
In the case of a partly erupted tooth, where some surfaces were not visible, these were recorded as "sound". No part of the t o o t h was wisible. Includes both unerupted and congenitally absent teeth. Teeth extracted for orthodontic reasons. N o attempt was made to decide if the tooth was sound o r carious prior to extraction. The surfaces were recorded as "decayed" if there was a carious cavity not invoMng tb~: p u ~ , (i.e. the cavity that was restorable without pulpal treatmer~'~.). Arrested caries was not diagnosed as "'decayed". The c a d o u s cavity that involved the pulp (i.e. the cavity that necessitated extraction o f the tooth or root canal treatment). F o r guidance, a deciduous tooth with a break in the marginal ridge o f more than two-thirds its width was usually recorded as "unrestorable". Extracted due to caries or missing d u e ~ o trauma. Does not include exfotiated teeth or extractions due to orthodontics. Surfaces containing a permanent restoration o f any material. Lesions containing a temporary dressing or when a filling has been partially or completely lost were recorded in the appropriate category o f "decayed". A surface that had a fillingand a carious lesion, unless the lesion was c o d e d as 5 (unrestorable), in which case the filling was ignored. Surfaces which were fractured, b u t not decayed, o r surfaces which had been .fractured but restored with a crown or bonding.
Results The main findings of t h e survey can b e summarized as follows:
Five-year-olds (Tables 1 and 2) (I) (2) (3) (4) (5)
The average number o f decayed, extracted and filled teeth ( d e f ) p e r child was 4-82. F o u r o u t o f every five children ( 8 1 - 3 ~ ) a l r e a d y suffer from dental caries. Less than o n e child in five (18-75~o) had perfectly healthy teeth. The average 5-year-old has o n e q u a r t e r •f his deciduous teeth affected by decay. At the age o f 5 m o r e deciduous teeth had been extracted than had been filled. TABLE I. Five-year-olds--all children: Deciduous teeth and surfaces Teeth standard Mean error Decayed (d) Extracted (e) Filled (f) def
3-76 0-55 0-51 4,82
0"30 0"13 0"10 0"35
Surfaces Standard Mean error 7'99 2"69 I"00 11"70
0"89 0"64 0"19 1"18
I28
R. J. Izon, R. C. Pulten and G. A. Scivier TABLE2. Five-year-olds--by school: Deciduous teeth ,
.
H,
St Paul's Mean deft Children with no experience of decay ~/o Children with deft o f ten or more
3-47
.,r
,
School Our St All Lady's James' Saints 3.67
4.31
4.74
,
Trinity
Hundenon
All children
5-33
5-69
4-82
33-3
33-3
17-1
14.3
17-7
11-2
18-8
8-9
16.7
11~4
11-4
13-7
15.7
13-2
(6) Only I0 ~o o f all decayed deciduous teeth were filled and otherwise sound. (7) 78 % o f all affected deciduous teeth ~were still actively decaying. (8) One child in eight (13-2%) had 10 or more deciduous teeth affected by decay (i.e. half or more o f t h e deciduous dentition).
(9) There was considerable variation between children in different schools. There was much more dental caries in schools south o f the River Wye and in the west o f the city. The lowest amounts of decay were found in the schools east o f the city centre. The average child at Hunderton had 64 % more affected teeth than his counterpart at St. Paul's. One child in three (33.3 %) at St. Paul's h a d no experience o f decay, only one child in nine (I t-2~o) at Hunderton. Fifteen-year-olds (TabIes 3 :and 4) (1) The average 15-year-old in Hereford had over nine permanent teeth affected by decay (Mean DMF=9-15). (2) Only one child in 140 (0.71%) had completely healthy teeth. (3) Two out o f five 15-year-olds (40-8%) had t0 or more permanent teeth affected by decay~ (4) 42.5% o f all decayed permanent teeth were still actively decaying. 'TABLE 3. Fifteen-year-olds--all children: Permanent teeth and surfaces
Decayed (D) Missing (M) Filled (F) DMF r
(5)
Teeth Standard Mean error
Surfaces Standard Mean error
3-89 0-47 4.79
5.21 2-35 9.63
0.46 0-47 0.67
17"18
1-04
0.29 0-09 0-28
9-15 i
.
,.,,
:
,J
,,,,
0-40 ,
,
,.,.,
_
,
i
,
,,
t
,,,
There was considerable 'variation between children in different schools, broadly following the geograph~:cal divisions found in 5-year-old children. Whitecross had the highest, m e a n D M F , which represented 76~o more decaying teeth ~than at Aylestone. At Aylestone, 15 ~ of children h a d l 0 or more decayed permanent teeth, at Whitecross, 67~o :had 10 o r more affected teeth.
Dental caries in ttereford children
129
"I'An~.E4. Fifteen-year-olds--byschool: Permanent teeth .
.
.
.
.
r,
,
i
,
School Aylestone DMFT Children with no experience of decay YoChildren with DMFT of 10 or more ,
,
Haywood Bishop's
Whitecross
All children
6-59
8-25
1t-16
11-63
9"15
2-7
0.0
0-0
0.0
0-7
14-9
33.0
58.7
66.7
,
r
r
40'8 ,,,
i
,,
Discussion For most dental surgeons, the majority o f these findings will confirm t:heir clinical impressions built up over a number of years in practice in Hereford. The results indicate very high levels o f dental caries in 5 and IS-year-old children. What may come as more Of a surprise are the figures dealing with a proportion of decayed teeth that have received treatment. "42-5 ~ o f all decayed permanent teeth need attention" and "78 ~o o f all affected deciduous teeth still actively decaying" are quite horrifying statistics suggesting that dentists just cannot keep pace with the treatment o f such a widespread disease. The problem is obviously how to reduce the appallingly high level o f dental caries in children to manageable proportions so that the scarce resources, both financial and .professional, can better cope with the situation. Eor ~hat reason, a dental care programme must have its basis in the prevention of disease rather than treatment of its consequences. The only preventive measure shown to be effective on a community basis is :fluoridation. TABLE5. Five-year-olds--deciduousteeth ,
Hereford--1977 Scun~horpe--1969* Scunthorpe--1975t Birmingham--1976,
,
,
i
,,,,,,,
,,
deft
~o Children With no experience of decay
YoChildren with deft,of 10 or more
4..82 4.28 1-80 1.96
18"8 20.9 45.9 46.0
13-2 8.2 1-2 2-1
*Pre-fluoridationstudy. tFluoridated 1969. ~.Eluofidated 1964. Table 5 shows the results of :four studies carried out along similar lines to illustrate the effect that fluoridation might have upon the prevalence of dental caries in Hereford. The figures for Scunthorpe in 1969are similar to those of Hereford in t977. In 1975, after nearly six years o f fluoridation, the levels of dental decay :in Scunthorpe now approximate to those of Birmingham. It would not be unreasonable to expect similar dramatic reductions in the prevalence o f dental caries in Hereford children following fluoridation. The responsibility for dental health is shared by the Government, the Profession and the Community, both collectively and individually. The attainment of dental health will only be realized b y a radical alteration from the belief that dental decay is an inevitable part ~of life t o an acceptance by the community o f safe and effective preventive measures.
130
R.J. Izon, R. C. Pullen and G. A. Scivier
Acknowledgements We wish to acknowledge the time and facilities accorded by the Area Health Authority and the County Education Officer o f Hereford and Worcester, without which this study would not have been possible. W.e extend our thanks for the analysis of the .data to the University o f Birmingham Dental School and to Miss Gillian Bradnock in particular for her help and advice. The examiners also wish to thank the three recorders, Miss R. A. White, Mrs J. G. Edwards and Miss D. Leng and Miss M. M. Halfacre for her secretarial assistance in the preparation of this paper. Our sincere thanks axe extended to the head teachers o f the schools concerned and t o The Grove School, Malvem, and o f course to the 555 children who so willingly and amiably took part in the survey.
The Prevalence ,of:Dental Caries in 5 and 15-year-old Hereford Children R: J. izon B.D.S.. D.D.P.H.R.C.S.
R. C: ,Pullen* B.D.S.
and G. A. Scivier .B,D,S., D.D.H,. D~D.P.H.R.C.S.
Hereford and 'Worcester Area Health ,4 uthority, Bedwardine House, Upper Wick Lane, Rushwick, Worcester
The survey involved the dental examination o f a random sample of 273 5-year-old chi'idren and 282 15-year.,old :children attending schools withira the City of Hereford. The results reveal a high prevalence of dental caries, a geographical variation .within the city, and a high percentage of affected teeth which are actively decaying. The community's possible 'response to the problem is discussed.
Introduction The purpose of" this survey was to investigate the prevalence of dental caries in 5 and 15-year-old children in Hereford, and to transform intb meaningful statistical figures the situation that the practising dentist sees in a clinical setting. In Short, it hopefully answers the question " H o w bad are children's teeth in Hereford ?" Instead o f the reply "Pretty b a d " or "'Not very g o o d , , which are comments based on that individual's clinical opinion o f a specific section o f the community and which in truth mean very little, one can now produce statements o f much greater detai:l wit'h correspondingly greater confidence. Providing the same diagnostic criteria and the conduct o f the examinations are,rigorously adhered ,to, it 'will be possible t o compare future 5 and 15-year-olds with their present-day counterparts. It is hoped that fluoridation will soon be introduced in Hereford, and the existence o'f reliable base-line ,data will thus allow comparisons to be made of future alterations in the level o f dental caries.
Subjects Two age groups were chosen, those aged 5 and 15 on 31 March 1977. Theadvantages o f 5-year-old children are that they are easily accessible, being in their first year of primary schoOl, in that they provide .a measure of decay for deciduous teeth and thirdly that any marked reduction in the level o f dental .caries due .to fluoridation will first be reflected in the younger age groups. The advantages o f choosing 15-year-olds for the survey are that they .too are easily accessible for sampling, being in their .last full y e a r o f school life and that information concerning the permanent dentition can b e ascertained without the complications of deciduous teeth being present, as one would have with, say, 12-year-olds. *Also at: New House, Garway Hill, Hereford. 0038-3506/78/920.3-0125 S01.O0/0
© 1978 The Society of Communily Medicine
126
R. J. lzon; R. C. Pullen and G. A. ~civier
~?ive-year-olds There are 13 schools within the city :that :provide education for 5-year-olds. Rather than have ,to disturb all these schools, it was decided to take a random sample o f six. The I3 schools were weighted according to their number o f 5-year-old .pupils, and using random number tables, the following six schools were selected: All Saints' Parochial Infants School Hunderton Infants School Our Lady's Roman Catholic Primary School St James' Church of England Infants School St Paul's Church of England Primary School Trinity Primary School The head teachers were approached and willingly gave their consent to the survey. Lists o f "children aged between 5 and 6 on 31 March 1977 were obtained from each o f the six schools. These children were arranged alphabetically and three out o f every four were sampled-a total o f 304. Two hundred and seventy-three 5-year-old children with a n average age of 5 years 6 months (and 10,days) were eventually examined. This was 9 0 ~ of those sampled, the remainder having moved o r been absent :through illness, and represented about 33 ~ of all 5-year-old children in the city. Fifteen-year-olds There are four maintained schools within the city providing education for 15-year-olds. Aylestone School Bishop of Hereford's Bluecoat School Haywood High School Whitecross School The head teachers were approached and all willingly gave their consent to the survey. One headmaster requested that a letter be sent tO the parents of all children who were sampled to tffke part. This was done, and we h a d n o refusals for examination. Lists ofchiidren aged between 15 and 16 on 31 March 1977 were obtained from each of the four schools. These children were ,arranged alphabetically and two out of every five were sampled--a total of 328. Two hundred and eighty-two 15-year-old children with an average age of 15 years 6 months(and 3 days)were eventually examined. This was 8 6 ~ of those sampled, and represented about 34 Yo of all 15-year-old children in the city. The last .week in March was chosen f o r the clinical examinations. Besides being :roughly the mid-point of the academic year, absenteeism was thought to be lower, certainly than the main winter months, and one did not encroach upon the summer term with its ,more interesting pursuits, not to mention examinations. Calibration The results and consequences o f epidemiological studies are invalid unless the methods of data collection are standardized and the criteria for identifying the conditions are Clearly defined and reproducible. A pre-pilot, pilot, calibration ,and :reproducibility studies were hdd for the three examiners and their respective recorders. We were thus able t o assess and to keep inter-and intra- examiner variability within acceptable statistical limits. The Clinical Examination The children were examined in the chair of a mobile dental unit. Illumination was by means o f a .60 W bulb in an Angtepoise lamp. Plane No. 4 disposable mirrors and probes were used, ~he probes being of a type with replaceable points and changed after every 10 examinations.
Dental caries in Hereford children
127
The diagnostic criteria and surface codes were as follows:
COdes 0 Sound 1 2
Unerupted Extracted
(ortho) 4
Decayed
5
Decayed (unrestorabte)
6
Missing
7
Filled
8
Filled and carious Traumatized
9
In the case of a partly erupted tooth, where some surfaces were not visible, these were recorded as "sound". No part of the t o o t h was wisible. Includes both unerupted and congenitally absent teeth. Teeth extracted for orthodontic reasons. N o attempt was made to decide if the tooth was sound o r carious prior to extraction. The surfaces were recorded as "decayed" if there was a carious cavity not invoMng tb~: p u ~ , (i.e. the cavity that was restorable without pulpal treatmer~'~.). Arrested caries was not diagnosed as "'decayed". The c a d o u s cavity that involved the pulp (i.e. the cavity that necessitated extraction o f the tooth or root canal treatment). F o r guidance, a deciduous tooth with a break in the marginal ridge o f more than two-thirds its width was usually recorded as "unrestorable". Extracted due to caries or missing d u e ~ o trauma. Does not include exfotiated teeth or extractions due to orthodontics. Surfaces containing a permanent restoration o f any material. Lesions containing a temporary dressing or when a filling has been partially or completely lost were recorded in the appropriate category o f "decayed". A surface that had a fillingand a carious lesion, unless the lesion was c o d e d as 5 (unrestorable), in which case the filling was ignored. Surfaces which were fractured, b u t not decayed, o r surfaces which had been .fractured but restored with a crown or bonding.
Results The main findings of t h e survey can b e summarized as follows:
Five-year-olds (Tables 1 and 2) (I) (2) (3) (4) (5)
The average number o f decayed, extracted and filled teeth ( d e f ) p e r child was 4-82. F o u r o u t o f every five children ( 8 1 - 3 ~ ) a l r e a d y suffer from dental caries. Less than o n e child in five (18-75~o) had perfectly healthy teeth. The average 5-year-old has o n e q u a r t e r •f his deciduous teeth affected by decay. At the age o f 5 m o r e deciduous teeth had been extracted than had been filled. TABLE I. Five-year-olds--all children: Deciduous teeth and surfaces Teeth standard Mean error Decayed (d) Extracted (e) Filled (f) def
3-76 0-55 0-51 4,82
0"30 0"13 0"10 0"35
Surfaces Standard Mean error 7'99 2"69 I"00 11"70
0"89 0"64 0"19 1"18
I28
R. J. Izon, R. C. Pulten and G. A. Scivier TABLE2. Five-year-olds--by school: Deciduous teeth ,
.
H,
St Paul's Mean deft Children with no experience of decay ~/o Children with deft o f ten or more
3-47
.,r
,
School Our St All Lady's James' Saints 3.67
4.31
4.74
,
Trinity
Hundenon
All children
5-33
5-69
4-82
33-3
33-3
17-1
14.3
17-7
11-2
18-8
8-9
16.7
11~4
11-4
13-7
15.7
13-2
(6) Only I0 ~o o f all decayed deciduous teeth were filled and otherwise sound. (7) 78 % o f all affected deciduous teeth ~were still actively decaying. (8) One child in eight (13-2%) had 10 or more deciduous teeth affected by decay (i.e. half or more o f t h e deciduous dentition).
(9) There was considerable variation between children in different schools. There was much more dental caries in schools south o f the River Wye and in the west o f the city. The lowest amounts of decay were found in the schools east o f the city centre. The average child at Hunderton had 64 % more affected teeth than his counterpart at St. Paul's. One child in three (33.3 %) at St. Paul's h a d no experience o f decay, only one child in nine (I t-2~o) at Hunderton. Fifteen-year-olds (TabIes 3 :and 4) (1) The average 15-year-old in Hereford had over nine permanent teeth affected by decay (Mean DMF=9-15). (2) Only one child in 140 (0.71%) had completely healthy teeth. (3) Two out o f five 15-year-olds (40-8%) had t0 or more permanent teeth affected by decay~ (4) 42.5% o f all decayed permanent teeth were still actively decaying. 'TABLE 3. Fifteen-year-olds--all children: Permanent teeth and surfaces
Decayed (D) Missing (M) Filled (F) DMF r
(5)
Teeth Standard Mean error
Surfaces Standard Mean error
3-89 0-47 4.79
5.21 2-35 9.63
0.46 0-47 0.67
17"18
1-04
0.29 0-09 0-28
9-15 i
.
,.,,
:
,J
,,,,
0-40 ,
,
,.,.,
_
,
i
,
,,
t
,,,
There was considerable 'variation between children in different schools, broadly following the geograph~:cal divisions found in 5-year-old children. Whitecross had the highest, m e a n D M F , which represented 76~o more decaying teeth ~than at Aylestone. At Aylestone, 15 ~ of children h a d l 0 or more decayed permanent teeth, at Whitecross, 67~o :had 10 o r more affected teeth.
Dental caries in ttereford children
129
"I'An~.E4. Fifteen-year-olds--byschool: Permanent teeth .
.
.
.
.
r,
,
i
,
School Aylestone DMFT Children with no experience of decay YoChildren with DMFT of 10 or more ,
,
Haywood Bishop's
Whitecross
All children
6-59
8-25
1t-16
11-63
9"15
2-7
0.0
0-0
0.0
0-7
14-9
33.0
58.7
66.7
,
r
r
40'8 ,,,
i
,,
Discussion For most dental surgeons, the majority o f these findings will confirm t:heir clinical impressions built up over a number of years in practice in Hereford. The results indicate very high levels o f dental caries in 5 and IS-year-old children. What may come as more Of a surprise are the figures dealing with a proportion of decayed teeth that have received treatment. "42-5 ~ o f all decayed permanent teeth need attention" and "78 ~o o f all affected deciduous teeth still actively decaying" are quite horrifying statistics suggesting that dentists just cannot keep pace with the treatment o f such a widespread disease. The problem is obviously how to reduce the appallingly high level o f dental caries in children to manageable proportions so that the scarce resources, both financial and .professional, can better cope with the situation. Eor ~hat reason, a dental care programme must have its basis in the prevention of disease rather than treatment of its consequences. The only preventive measure shown to be effective on a community basis is :fluoridation. TABLE5. Five-year-olds--deciduousteeth ,
Hereford--1977 Scun~horpe--1969* Scunthorpe--1975t Birmingham--1976,
,
,
i
,,,,,,,
,,
deft
~o Children With no experience of decay
YoChildren with deft,of 10 or more
4..82 4.28 1-80 1.96
18"8 20.9 45.9 46.0
13-2 8.2 1-2 2-1
*Pre-fluoridationstudy. tFluoridated 1969. ~.Eluofidated 1964. Table 5 shows the results of :four studies carried out along similar lines to illustrate the effect that fluoridation might have upon the prevalence of dental caries in Hereford. The figures for Scunthorpe in 1969are similar to those of Hereford in t977. In 1975, after nearly six years o f fluoridation, the levels of dental decay :in Scunthorpe now approximate to those of Birmingham. It would not be unreasonable to expect similar dramatic reductions in the prevalence o f dental caries in Hereford children following fluoridation. The responsibility for dental health is shared by the Government, the Profession and the Community, both collectively and individually. The attainment of dental health will only be realized b y a radical alteration from the belief that dental decay is an inevitable part ~of life t o an acceptance by the community o f safe and effective preventive measures.
130
R.J. Izon, R. C. Pullen and G. A. Scivier
Acknowledgements We wish to acknowledge the time and facilities accorded by the Area Health Authority and the County Education Officer o f Hereford and Worcester, without which this study would not have been possible. W.e extend our thanks for the analysis of the .data to the University o f Birmingham Dental School and to Miss Gillian Bradnock in particular for her help and advice. The examiners also wish to thank the three recorders, Miss R. A. White, Mrs J. G. Edwards and Miss D. Leng and Miss M. M. Halfacre for her secretarial assistance in the preparation of this paper. Our sincere thanks axe extended to the head teachers o f the schools concerned and t o The Grove School, Malvem, and o f course to the 555 children who so willingly and amiably took part in the survey.