Australian Dental Journal, October, I965 371

A study of dental caries in a group of Western Australian children. Part IV. The bilaterality

of dental caries

Spyros E. Halikis, B.D.Sc. (Qld.)

Introduction The results of Cheyne and Drain have been The phenomenon of bilaterality of the pre- substantiated for the first permanent mOkU',("'

Sence of dental caries has been commented and for the deciduous molars(e) by this author upon by many authors but observations have in a previous study. been confined to individual teeth or types of Strusser and Dwyer") have noted that caries teeth. occurs with consistent bilaterality while

Brekhus'" first noted in 1928 that tooth mortality was bilaterally equal to a high degree of consistency. Knutson and Klein(*) recognized that tooth eruption and the occur- rence of caries in teeth are symmetrical and bilaterally equal, and they reported that the mortality of the lower first permanent molars of Hagerstown children tended to be constantly bilaterally equal. From information obtained while preparing for a controlled study on the efflcacy of silver nitrate as a n arrestor of dental caries, Bertram and Brown@) concluded that the phenomenon of bilaterality of dental caries withstood statistical analysis. Cheyne and Drain") found no demonstrable difference in permanent tooth loss between the right and left sides of the mouth for either sex.

Leigh(*) and Hyatt@) have attributed the bi- laterality of dental caries to the similar morphology of the tooth pairs. It is interest- ing to note that Hyatt demonstrated the phenomenon of bilaterality even in a popula- tion with a relatively low caries attack rate. Hadjimarkos has studied this phenomenon of bilaterality in terms of DMF teeth, and has shown that this characteristic peculiar to caries attack can be utilized profitably in the field of public health dentistry as a simplifled but accurate technique for measuring the dental status and dental needs of large popula- tion groups.

I t is the purpose of this paper to determine whether this phenomenon of bilaterality of dental caries can be demonstrated In terms of DMF teeth and surfaces (decayed, missing,

~

Received for publication, May, 1965. (1) Brekhus, P. J.-Investigations of loss of human "I Halikis, S. E.-The incidence of flrst permanent

teeth. J.A.D.A., 15: 4, 679-690 (ADr.) 1928. molar IOSY in Western Australian children. Austral. D. J.. 4: 3. 201-206 (June) 1959.

(2) Knutson, J. W., and Klein, H.-Studies of dental caries. Pa r t IV. Tooth mortality in elemen- tary school children. Pub. Health Rep., 53 : 6, 1021-1032 (June) 1938.

( 8 ) Bertram, F. P., and Brown, J., E., Jr.-Pheno- menon of bilateral dental caries : A statistical analysis. J.A.D.A., 30 : 17, 1392-1395 (Sept.) 1943.

( 0 ) Halikis, S. E.-The incidence of deciduous molar loss in Western Australian children. Austral. D. J., 5: 1, 32-37 (Feb.) 1960.

( 7 ) Strusser, H., and Dwyer, H. S.-Summary in dental caries. Chicago, American Dental Asso- ciation, 2nd ed.. 1941 (D. 214).

Leigh, R. W.-Summary in dental caries. Chicago, American Dental Association, 2nd ed., 1941 (p. 157).

(4) Cheyne, V. D., and Drain, C. L.-Dental caries (O) Hyatt, T. P.-Summary in dental caries. and permanent tooth extraction. J. D. Res., Chicago, American Dental Association, 2nd 1 9 : 6, 571-584 (Dec.) 1940. ed., 1941 (p. 132).

r

3 72

Right Age Last Standard

Birthday Mean Deviation

2 1.75 2 . 1 4 3 4 . 4 4 2 .31 4 5 .41 2 .11 5 5.58 2.31 6 6 .71 2 .24

Australian Dental Journal. October, 1965

years and fifteen years, as shown in Table 1. Of these 361 children between the ages of two years and six years were used in the study of the deciduous dentition, while 1,195 between the ages of five years and fifteen years were included in the studies of the permanent dentition.

Each child was examined while seated i n a dental chair. All examinations were conducted by the author with the use of a plane mouth mirror and a sharp sickle probe. Each child’s name, sex, and date of birth, and the date of examination were recorded. The teeth were examined in order from the lower left to the lower right and then from the upper left to the upper right. Each tooth was classified as present, unerupted, missing, or requiring extraction. Each surface of each tooth was classified as non-carious, carious, or filled. Teeth and surfaces which had been previously filled and had subsequently again become carious were classified as carious. Teeth known to have been lost through accident or for orthodontic reasons were excluded. The carious lesions recorded were those which can usually be observed on a careful clinical examination. Pits and fissures were considered carious if the point of a sharp probe required a definite pull for its removal or if softness was palpable. Proximal surfaces were con- sidered carious if a roughness was present capable of holding the point of a sharp probe. A tooth was considered due for extraction when its state was such that i t would not be normally repaired or where roots only remained.

Left

Standard Mean Deviation

1.58 2 .19 4 .52 2 .20 5 .65 2.31 5 .91 2.41 6.07 2 .32

TABLE 1 Age and sex distribution of 1,353 boys and girls examined in 1959 at the Custafson Dental Clinic,

Fremantle, Western Austral i

2 3 4 5 6

(Last Male Birthday)

2 .14 1.72 2 .43 2 .15 4 .39 2 .52 4 .36 2 .83 4 .88 2 .36 4 .93 2 .43 5 .26 2 .60 5 .06 2.47 5.17 2 .32 5 .19 1 .94

2 3 4 5 6 7 8 9

10 11 12 13 14 15

12 54 84 98

102

All ages

0 .26 0 . 0 4 0.10 0 .39 0 .05

12 27 46 55 41 54 68 60

51 37 32

641

Female

7 28 43 50 52 73 89 69 62 58 58 63 33 32

717

Both Sexes

19 35 89

105 93

127 157 129 117 113 106 114 70 64

1358

and filled) in the permanent dentition and defm teeth and surfaces (decayed, indicated for extraction, filled, and missing molars) in the deciduous dentition of a population with a high caries rate.

Material and method Subjects for this study were patients who

presented for examination a t the Gustafson Dental Clinic, Fremantle, Western Australia, during the period March, 1959, to the end of August, 1959. They consisted of a group of 1,358 boys and girls between the ages of two

TABLE 2 Urnparison of dejm (decayed, extraction indicated, fi l led, and deciduous molars missing) teeth between the right

and left sides of the mouths of children aged 2-6 years

Sex

Male

Female

The hypothesis that there is essentially no difference between the means 01 each age group csnnot be rejected at a 0.01 level of si@cance.

Degrees of

Froodom

22 52 90

108 80

t

0 .18 0 .02 0 .23 0 . 3 0 0 .55

Australian Dental Journal, October, I965 3 73

TABLE 3 Comparison of defm (decayed, extraction indicated, filled, and deciduous molars missing) tooth surfaces between

the right and left sides of the mouths of children aged 2-6 years

Right Left I Degrees Standard of Deviation Freedom

t Age Next

Birthday

2 3 4

6

2 3 4

i)

22 52 90

108 80

12 54 84 98

102

Standard Deviation

0.23 0.08 1.43 0.47 0.19

0.26 0.47 0.05 0.20 0.68

Sex

Mean

Mean

2.50 7.90

10.99 11.38 14.08

Standard Error

Mean

' 0.05 ' 0.11

0.09 0.06 0.12 0.20 0.25 0.30 0.27 0.47 0.46

Male

2.74 7.78 9.34

10.81 13.81

2.58 5 . 5 8 5.37 6.45 6.36

2.28 5.46 6.03 6.15 6.45

2.15 7.05 5.88 5.85 5.52

2.43 7.63

10.00 10.12 12.01

2.14 6.79 9.94

10.36 11.32

1.72 6.00 6.33 6.03 4.86

Female

I

The hypothesis that there is essentially no difference between the means of the right and left sides in each age group cannot be rejected at a 0.01 level of significance.

Results missing) teeth for the right and left sides, is shown in Table 2; expressed as defm tooth surfaces, the dental caries experience of the

The dental caries experience Of children two sides in these children is shown in between the ages of two Years and Six Table 3. Statistical analysis of these flgures Years, expressed defm (decayed, indicated reveals that the phenomenon of bilateral for extraction, filled, and deciduous molars occurrence of dental caries appears in the

TABLE 4 Comparison of DMF (decayed, missing, andfclled) teeth between the right and le f t sides of the mouths of children

Deciduous dentition

aged 5-15 years

Right Standard Error

of Difference

Age Last

Birthday

Differ- ence Sex Standard

Error Mean

0.07 0.44 1.24 1.98 2.12 2.89 3.94 4.90 6.20 6.76 7.22

0.08 0.67 1.28 2.00 2.39 3.03 4.33 6.05 7.14 7.30 8.53

5 6 7 8 9

10 11 12 13 14 15

0.05 0.12 0.12 0.10 0.11 0.21 0.24 0.29 0.38 0.43 0.42

0.04 0.58 1.22 1.91 2.32 2.74 3.94 5-25 6.25 7.49 7.50

0.03 0.11 0.12 0.12 0.15 0.22 0.24 0.35 0.36 0.43 0.40

0.03 -0.14

0.02 0.07

-0.20 0.15 0.00

-0.35 -0.05 -0.72 -0.28

0.06 0.16 0.17 0.16 0.19 0.30 0.34 0.45 0.52 0.61 0.58

Male

Female

5 6 7 8 9

10 11 12 13 14 15

0.05 0.11 0.10 0.06 0.12 0.18 0.25 0.35 0.30 0.50 0-52

0.06 0.65 1.37 2.08 2.36 3.05 4.10 5.96 7.24 7.57 8.84

0.02 0.02

-0.09 -0.08

0.03 -0.02

0.23 0.09

-0.10 -0.27 -0.31

0.07 0.16 0.13 0.08 0.17 0.27 0-35 0.43 0.40 0.69 0.69

The difference between the means in each 8ge group can be considered statistically s w c a n t when the difference is more than twice the standard error of difference.

3 7 4 Australian Dental Journal, October, I965

TABLE 5 Comparison of DMF (decayed, missing, and j i l l e d )

children

sex

Male

Female

The dif

Age Next

Birthday

> 6 7 x !)

10 11 12 13 14 15

5 t; 7 8 !)

10 11 12 13 14 15

*ence b e t w

Right

~

Mean

0.07 0.58 1.89 3.12 4.10 5.26 7.81 9.31

11.77 13.24 14.59

0.10 0.83 1.93 3.43 4 ' 00 5.33 7.93

11.02 13.33 14.56 17.86

Standar Error

0.03 0.18 0.23 0.23 0.24 0.39 0.54 0.61 0.77 1.06 1.04

0.06 0.16 0.19 0.15 0.26 0.34 0.43 0.42 0.74 1.36 1.21

!n the moans in each agi difference is more than twire the standard err61

deciduous dentition of this young group i n both the male and female. It is equally apparent whether caries experience be expressed as defm teeth or defm tooth sur- faces.

P e r m a n e n t d e n t i t i o n

The phenomenon of bilateral occurrence of caries is also demonstrated in the permanent dentition as shown in Tables 4 and 5. Statistical analysis confirms that the caries experience of the permanent teeth in the male and female between the ages of five years and fifteen years is bilaterally equal, whether expressed as DMF (decayed, missing or filled) teeth, or DMF tooth surfaces.

Hadjimarkos(lo) in his study of the dental condition of freshman students shows that the dental status and dental needs of the 17, 18, and 19-year-olds can be ascertained readily and accurately by limiting the observations on the condition of the teeth of either side of the mouth. It is obvious that this conclu- sion can be extended to any age group between

(lo)Hadjimarkos, D. M., and Storvick, Clara A.- Bilateral occurrence of dental caries. A stud'y of Oregon State College freshman students. Oral Surg., Oral Med. and Oral Path., 3: 9, 1206-1209 (Sept.) 1950.

surfaces between the right a n d left side8 of the mouths of 5-15 years

Left

Mean

0.05 0.73 1.85 3.19 4.13 5.47 7.60 9.49

12.52 14.62 15.43

0.06 0.90 2.05 3.64 4.45 5.59 7.51

11.44 13.39 15.91 19.57

ip can be co iifference.

Standard Error

0.03 0.16 0.22 0.25 0.27 0.43 0.52 0.74 0.78 1.08 1.21

0.04 0.16 0 . l!) 0.16 0.26 0.33 0.44 0.42 0.71 1.41 1.12

idered statis

Differ- ence

0.02 -0.15

0.04 -0.07 -0.03 -0.21

0.21 -0.18 -0.75 -1.38 -0.84

Standard Error

of Difference

0.04 0.22 0.32 0.36 0.36 0.57 0.75 0.96 1.09 1.51 1.59

0.04 -0.07 -0.12 -0.21 -0.36

0.24 0.42

-0.42 -0 .06 -1.35 -1.71

0.07 0.22 0.26 0.22 0.37 0.47 0.62 0.59 1.02 1.96 1.65

:ally significant when the

the ages of two years and fifteen years in both the male and female, and that it is true for both the deciduous and the permanent denti- tions in a high caries p~pula t ion . '~ ' ) (~*) (~~)

Summary Data obtained from the dental examination

of 1,358 boys and girls from two years of age to fifteen years of age a t the Gustafson Dental Clinic, Fremantle, Western Australia, were analysed to ascertain whether the phenomenon of bilateral occurrence of dental caries is present in these children.

Statistical analysis of data obtained from the examination of 361 children between the ages of two years and six years verifies that the caries experience of both the male and female of each age group in this population,

(11) Halikis, S. E.-A study of dental caries in a group of Western Australian children. Part I. The incidence of dental caries in permanent teeth. Austral. D. J., 7 : 6 , 465-470 (Dec.) 1962.

(12) Halikis, S. E.-A study of dental caries in a group of Western Australian children. Part 11. The incidence of dental caries in children aged 2-6 years. Austral. D. J., 8 : 2, 114-122 (Apr.) 1963.

(13) Halikis, S. E.-A study of dental caries in a group of Western Australian children. Part 111. Caries experience expressed as DMF tooth surfaces. Austral. D. J., 1 0 : 2, 132-138 (Apr.) 1965.

Australian Dental Journal, October, I965 375

whether expressed as defm teeth (decayed, extraction indicated, filled, deciduous molars missing or as defm tooth surfaces, is bilaterally equal.

Statistical analysis of data obtained from the dental examination of 1,195 children be- tween the ages of five years and flfteeen years (permanent teeth only), confirms that the phenomenon of bilateral occurrence of dental

caries exists in the male and female in each of these age groups for this population whether the caries experience be expressed as DMF (decayed, missing, filled) teeth, or as DMF tooth surfaces.

6 Hale Street, North Beach,

Western Australia.

Ecology Beyond the clearings the forest floor is carpeted with a n inextricable tangle of shrubs and exotic plants : esoteric mushrooms, voluptuous orchids, and sensuous, insatiable plants that lure insects into their clutches and devour them. In equatorial forests, these insects practically have the ground floor to themselves. There are very few great wild beasts, no huge pythons or anacondas, for there is little there for them to eat. And there is no sight or sound of birds, except at dawn and sunset, when a chorus of cries and singing breaks out from the treetops, where the birds and monkeys live within striking distance of the fruit, t.he blossoms and the butterflies.-Lionel Birch, RPalitcis, April, 1965.