clinical-detection-of-caries-in-the-primary-dentition-with-and-without-bitewing-radiography.docx

Australian Dental Journal 2009; 54: 23–30

S C I E N T I F I C A R T I C L E

doi: 10.1111/j.1834-7819.2008.01084.x

Clinical detection of caries in the primary dentition with and without bitewing radiography

B Newman,* WK Seow,< S Kazoullis, D Ford, T Holcombe*

*Southside Health Service District, Queensland Health.

<School of Dentistry, The University of Queensland.

Private Practice, Queensland.

ABSTRACT

Background: Inadequate detection of caries in the primary dentition due to non-use of bitewing radiography is commonly encountered in paediatric practice. The present study investigated the increased benefits of using bitewing radiography in addition to the visual-tactile examination technique for detection of primary dentition caries in a non-fluoridated community, and determined the prevalence of ‘‘hidden’’ occlusal caries in the primary dentition.

Methods: Primary teeth were scored for caries at the restorative threshold using a visual-tactile technique followed by bitewing radiographic examination in a sample of 611 schoolchildren aged 6.4 ± 0.5 yrs to 12.1 ± 0.8 yrs residing in a non-fluoridated city.

Results: Overall, at the restorative threshold, the visual-tactile technique could detect 62 per cent of occlusal caries compared to 74 per cent for bitewing radiography (p < 0.001). The prevalence of ‘‘hidden’’ occlusal caries was 12 per cent. In contrast, for primary molar proximal surface caries, the visual-tactile technique could detect only 43 per cent of caries compared with 91 per cent for bitewing radiography (p < 0.001).

Conclusions: In the primary dentition, use of bitewing radiography increases the detection rate of proximal surface caries substantially. It is recommended that bitewing radiography be included as part of the routine examination of children with proximal surfaces that cannot be visualized.

Key words: Primary dentition caries, deciduous caries, hidden caries, bitewing radiography.

Abbreviations and acronyms: dmft = decayed, missing due to caries, filled, teeth; dmfs = decayed, missing due to caries, filled, surfaces.

(Accepted for publication 23 April 2008.)

INTRODUCTION

The majority of studies which investigate the efficacy of the visual-tactile technique for caries detection have been largely in vitro, and performed mainly on extracted

permanent teeth.1–7 To date, the few studies performed on primary teeth are in vitro reports, and there is a paucity of in vivo studies on the sensitivity and specificity of the visual-tactile technique for caries diagnosis in the primary dentition.

Although bitewing radiography for diagnosis of caries in individual patients is an established clinical technique, the value of bitewing radiography for the detection of caries in

large population groups is still controversial.8 Previous studies addressing this issue were performed mainly in adults and adolescents, and there is limited information for the primary dentition. The increased benefit of bitewing radiographs over

ª 2009 Australian Dental Association

visual examination for assessing caries experience in young children for epidemiological purposes is thus

unclear.6 Studies in the permanent dentition suggest that the improvement in caries detection was generally in the order of around 3–5 per cent, and that bitewing radiography probably has greatest value in those

populations with the highest caries rates.9–13 In addi-tion, ‘‘hidden’’ occlusal caries which refer to caries that cannot be diagnosed by the visual-tactile techniques can be revealed only by radiographic examination. Although ‘‘hidden’’ caries is increasingly recognized as an important clinical entity in paediatric dentistry, its prevalence in the primary dentition has not been reported previously.

The present study aimed firstly, to investigate the increased benefits of bitewing radiography for detection of occlusal and proximal caries compared to the visual-tactile technique in the primary dentition, and to detect

23

the prevalence of ‘‘hidden’’ caries in the primary denti-tion. The second aim was to compare the sensitivity and specificity of the visual-tactile clinical examination with bitewing radiographic examination for detection of caries in the primary dentition for children at Australian primary school years 1, 3, and 7 (aged approximately 6, 8 and 12, respectively). The sensitivity of a technique is related to the accuracy of detecting disease when it is present, while the specificity is related to the accuracy of diagnosing the

absence of disease.14

SUBJECTS AND METHODS

The present study was approved by the relevant institutional Human Research Ethics Committees. The subjects were schoolchildren who were scheduled on their records to have a full dental examination at primary schools in the Logan-Beaudesert area, a non-fluoridated community located in the Australian state of Queensland. The consent rate for the study was 87 per cent.

The examinations were carried out by four examiners who were calibrated for intra- and inter-examiner variability. The calibration examinations were per-formed on six children aged 5–12 years who were examined twice by each of the examiners on two separate occasions, a week apart. The Kappa statistic was used to test inter- and intra-

examiner reliability.15

The children were examined in school dental clinics. The visual-tactile examination was performed in the dental chair using an operating light, a dental mirror and dental explorer. Teeth were dried with a triplex syringe prior to examination. Bitewing radiographs were exposed using standard techniques. These radio-graphs were read using a radiographic viewer without magnification. The radiographs were read blind to the data from the visual-tactile examination. All primary

tooth surfaces were scored for caries using criteria listed in Table 1.

The total dmft figure, i.e., decayed (d), missing due to caries (m) and filled (f) teeth (t) was calculated from the results for the visual-tactile examination and also for the radiographic examination respectively. The diagnostic information from bitewing radiographic examination was used to compute the total dmfs, i.e., decayed (d), missing due to caries (m), filled (f) surfaces

(s) values for each age group.

Table 1 describes the visual-tactile (clinical) and radiographic criteria employed in the present study. As can be noted in the table, a visual-tactile score of C3 (cavitations which are detected with an explorer) or a radiographic score of R3 (radiolucent areas which are present in the inner half of enamel) are thresholds which are generally employed to determine the need for

restorative treatment. These criteria provide the restor-ative threshold which determines restorative needs in a health service district considered high risk for caries. The lesions which meet the criteria C3 ⁄ R3 to C5 ⁄ R5 (clinical ⁄ radiographic evidence that caries is present in dentine) and C8–C9 ⁄ R8 (clinical ⁄ radiographic evidence of recurrent caries) were thus categorized as caries present to follow generally accepted clinical guidelines for caries diagnosis. Those which meet the criteria of C1 ⁄ R1 and C2 ⁄ R2 were considered non-carious (enamel) lesions (clinical ⁄ radiographic evidence that lesions are limited to enamel only).

Sensitivity was computed by determining the pro-portion of carious surfaces that were detected respec-tively, from visual-tactile examination and bitewing technique compared to the total number of lesions that can be detected by both techniques. Specificity was computed by determining the proportion of non-carious surfaces that were detected respectively, from visual-tactile examination and bitewing technique

Table 1. Clinical and radiographic criteria employed in the present study

Clinical

Radiographic

C1

– Sound surface

R1

– Sound

C2

– Discoloured surface which the sickle explorer could not enter

R2

– Radiolucency in outer half of enamel

C3

– Decayed surface which the sickle explorer withdrew with some

R3

– Radiolucency in inner half of enamel

resistance

C4

– Decayed lesion, not involving pulp, in which the sickle explorer

R4

– Radiolucency in the dentine

moved freely

C5

– A lesion involving pulp

R5

– Radiolucency with obvious spread in the outer half of the

dentine (less than halfway through to the pulp)

C6

– Restoration present-amalgam

R6

– Radiolucency with obvious spread in the inner half of the

dentine (greater than halfway through to the pulp)

C7

– Restoration present-plastic

R7

– Filled surface and sound

C8

– Restored with recurrent caries- amalgam

R8

– Filled, with secondary caries (radiolucency and filling on

the same surface)

C9

– Restored with recurrent caries-plastic

R9

– Extracted due to caries

C10

– Fractured amalgam restoration no caries-needs redoing

C11

– Fractured plastic restoration no caries-needs redoing

C12

– Extracted due to caries

C13

– Fractured teeth-trauma

24 ª 2009 Australian Dental Association

compared to the total number of non-carious surfaces determined by both techniques.

Sensitivity and specificity were determined at the C3 ⁄ R3 level which is considered the level at which restorative work is generally indicated for the commu-nity under study (restorative threshold). For compari-son purposes, specificity and sensitivity were also determined at C2 ⁄ R2 level.

Data were recorded in comprehensive data charts and analysed using the Chi-square, student’s t-test and ANOVA tests. A level of 0.05 was employed to determine statistical significance.

RESULTS

The intra- and inter-examiner consistencies were high, and there was substantial agreement reached among the four examiners. The unweighted Kappa statistic for both intra- and inter-examiner variability for visual-tactile examination and bitewing radiography was 0.76.

Demography of study population

The study sample consisted of a total of 611 primary school children (322 boys and 289 girls) from a total of nine schools in the Logan-Beaudesert health service district of Queensland. The region is non-fluoridated and has one of the lowest socio-economic status in the state. The children examined for primary denti-tion caries were selected from primary school Year 1 (n = 242, mean age of 6.4 ± 0.5 yrs), Year 3 (n = 246,

Detection of primary dentition caries

mean age of 8.5 ± 0.4 yrs) and Year 7 (n = 123, mean age of 12.1 ± 0.8 yrs). The children were randomly selected on the basis that they were scheduled for their two-year recall examination within the public school dental programme.

Comparison of dmft and dmfs determined by visual-tactile examination with and without bitewing radiography

Table 2 shows the differences in dmft and dmfs values obtained with and without bitewing radiography. As shown in the table, the mean dmft rates obtained from visual-tactile examination were 4.1 ± 4.1 for primary school Year 1, 3.4 ± 2.8 for Year 3 and 1.3 ± 1.7 for Year 7. When bitewing radiographs were employed, the dmft increased to 4.9 ± 4.2 in Year 1, 4.0 ± 2.9 in Year 3 and 1.5 ± 1.8 in Year 7 (Table 2). As shown in Fig 1, the percentage increases in dmft rates when bitewing radiography was employed was around 20 per cent for Year 1 (p = 0.05) and Year 3 (p = 0.01), and 13 per cent for Year 7 (n.s.).

In the case of dmfs, the rates obtained from visual-tactile examination were 8.3 ± 11.8 for Year 1 primary school, 5.9 ± 6.7 for Year 3 and 2.5 ± 3.9 for Year 7 (Table 2). When bitewing radiographs were employed, the dmfs increased to 9.6 ± 12.1 in Year 1, 7.2 ± 7.0 in Year 3 and 3.0 ± 4.5 in Year 7. As shown in Fig 2, the percentage increases in dmfs rates when bitewing radiography was employed was around 16 per cent for Year 1 and 20 per cent for each of Years 3 and 7 (n.s. for Year 1, p < 0.05 for Year 3 and n.s. for Year 7).

Table 2. dmft and dmfs obtained using visual-tactile (clinical) and radiographic examination techniques

Year 1 (Mean age 6.4 ± 0.5 yrs)



N = 242 children

N = 246 children

N = 123 children

N = 1843 primary teeth



dmft

Visual-tactile (clinical)

Mean

4.1

3.4

1.3

SD

4.1

2.8

1.7

Visual-tactile + radiographic

Mean

4.9

4.0

1.5

SD

4.2

2.9

1.8

Difference

Mean

0.8

0.6

0.2

SD

1.3

1.2

0.6

p-value (visual-tactile vs. radiograph)

p = 0.05

p = 0.01

n.s.

dmfs

Visual-tactile (clinical)

Mean

8.3

5.9

2.5

SD

11.8

6.7

3.9

Visual-tactile + radiographic

Mean

9.6

7.2

3.0

SD

12.1

7.0

4.5

Difference

Mean

1.3

1.3

0.5

SD

1.8

1.7

1.2

p-value (visual-tactile vs. radiograph)

n.s.

p = 0.01

n.s.

n.s. = not significant.

ª 2009 Australian Dental Association 25

B Newman et al.

Fig 1. Caries experience of children at primary school Years 1, 3 and 7 obtained using visual-tactile technique with and without bitewing radiographs expressed in percentages of dmft.

*The difference in dmft among the year groups using visual-tactile technique with and without radiographic examination is statistically significant (p < 0.001).

120

*p < 0.001

dmfs Percentage Difference

dmfs VT alone

100

80

cent

60

per

40

20

0

Year 7meanage12.1±0.8years

Year 1meanage6.4±0.5years

Year 3

mean age8.5±0.4years

All yearsmeanage8.4±2.2years

Fig 2. Caries experience of children at primary school Years 1, 3 and 7 obtained using visual-tactile technique with and without bitewing radiographs expressed in percentages of dmfs.

*The difference in dmfs among the year groups using the visual-tactile technique with and without radiographs is statistically significant (p < 0.001).

Sensitivity and specificity of visual-tactile and bitewing radiographic examination techniques

The sensitivity of occlusal and proximal caries detection at the restorative threshold of C3 ⁄ R3 for the visual-

tactile and bitewing radiography is depicted in Table 3, while the corresponding specificity values are shown in Table 4.

As shown in Table 3, in total, the visual-tactile technique showed that sensitivity of caries detection at restorative threshold (C3 ⁄ R3) for occlusal surfaces varied from 0.56 for the maxillary first primary molar to 0.73 for the maxillary second primary molar. By contrast, for proximal primary molar surfaces, the visual-tactile technique showed significantly lower sensitivity ranging from 0.31 for the mandibular second primary molar to 0.52 for the mandibular first primary molar (p < 0.001) (Table 3).

In contrast, the bitewing technique gave sensitivity values for occlusal surfaces ranging from 0.66 for the maxillary second molar to 0.78 for the mandibular second molar. For proximal molar caries detection using the bitewing technique, the sensitivity values were significantly higher, and ranged from 0.89 for the mandibular second molar and the maxillary first molar, to 0.93 for the mandibular first primary molar (Table 3).

Overall, the sensitivity for bitewing radiography for occlusal surfaces was 0.74 compared to 0.62 for the visual-tactile technique (Table 3). The additional 12 per cent of occlusal lesions which were detected from bitewing radiographs but not detectable by visual-tactile examination alone is the prevalence rate of occlusal

‘‘hidden’’ caries.16

For proximal caries detection at restorative thresh-old, the sensitivity was 0.91 compared to only 0.43 for the visual-tactile technique (p < 0.001). For both visual-tactile and bitewing radiography technique, specificity values at the restorative level of C3 ⁄ R3 for all primary occlusal and proximal tooth surfaces are very high (> 0.90; p < 0.001) (Table 4).

At the non-restorative level of C2 ⁄ R2 (Table 5), the sensitivity values are similar at 0.70 for caries detection of occlusal caries using the visual-tactile technique and 0.65 for bitewing radiographs. However, the sensitivity was only 0.43 for proximal surface caries detection in all primary molar teeth but at the non-restorative level, specificity values for the visual-tactile technique for detection of both occlusal and proximal surfaces was high (0.94 and 0.99, respectively) (Table 6).

DISCUSSION

Although it is well accepted that bitewing radiography has additional benefit in the detection of non-cavitated and small cavitated proximal lesions, evidence for their value in epidemiological studies is still controversial. Hopcraft

and Morgan17 reported that a clinical exam-ination detected only 60 per cent of all occlusal and proximal dentine caries on posterior teeth of young adults, and suggested that epidemiological surveys



Table 3. Sensitivity of occlusal and proximal caries detection using visual-tactile and bitewing examinations at the restorative threshold

Occlusal surfaces

N

Sensitivity

Visual-tactile

Bitewing

Y1

Y3

Y7

All

p-value

Y1

Y3

Y7

All

p-value

Maxillary D

969

0.64

0.39

0.67

0.56

p < 0.001

0.70

0.89

0.50

0.74

p = 0.05

Maxillary E

1099

0.77

0.68

0.65

0.73

p = 0.01

0.65

0.62

0.74

0.66

n.s.

Mandibular D

948

0.69

0.36

0.75

0.58

p < 0.001

0.82

0.67

0.75

0.76

p = 0.01

Mandibular E

1084

0.74

0.34

0.56

0.59

p < 0.001

0.77

0.77

0.82

0.78

n.s.

All occlusal surfaces

0.72

0.42

0.63

0.62*

p < 0.001

0.74

0.73

0.75

0.74*

n.s.

N

1843

1785

472

4100

1843

1785

472

4100

p-value

n.s.

p < 0.001

p < 0.001

p = 0.01

n.s.

p < 0.001

p < 0.001

p = 0.05

Proximal surfaces

N

Visual-tactile

Bitewing

Y1

Y2

Y3

All

p-value

Y1

Y3

Y7

All

p-value

Maxillary C

1787

0.67

0.91

0.6

0.74

n.s.

0.72

0.36

0.60

0.59

p < 0.001

Mandibular C

1635

0.33

1.00

1.0

0.60

p < 0.001

0.89

0.50

N ⁄ A

0.67

p < 0.001

Maxillary D

1932

0.43

0.46

0.41

0.44

n.s.

0.92

0.85

0.91

0.88

n.s.

Maxillary E

2192

0.44

0.42

0.38

0.42

n.s.

0.89

0.94

0.95

0.92

n.s.

Mandibular D

1900

0.55

0.45

0.44

0.52

p < 0.001

0.96

0.90

0.82

0.93

p = 0.01

Mandibular E

2177

0.42

0.15

0.64

0.31

p = 0.01

0.93

0.95

0.89

0.89

n.s.

All proximal surfaces

0.47

0.38

0.46

0.43

n.s.

0.92

0.9

0.88

0.91

n.s.

N

5355

5083

1185

11623

5355

5083

1185

11623

p-value

p < 0.001 p = 0.05 p < 0.001

n.s.

p < 0.001 p = 0.01

p < 0.001

n.s.

‘‘Hidden’’ occlusal caries: *Difference between visual-tactile and bitewing sensitivity values: 0.12.

Table 4. Specificity of occlusal and proximal caries detection using visual-tactile and bitewing examinations at the restorative threshold

Primary tooth

Specificity

Visual-tactile

Bitewing

Y1

Y3

Y7

All

p

Y1

Y3

Y7

All

p

Occlusal

Maxillary D

0.97

0.99

0.96

0.98

n.s.

0.96

0.96

0.97

0.96

n.s.

surfaces*

Maxillary E

0.93

0.97

0.96

0.95

n.s.

0.95

0.98

0.95

0.96

n.s.

Mandibular D

0.97

0.97

0.94

0.97

n.s.

0.95

0.94

0.94

0.94

n.s.

Mandibular E

0.94

0.97

0.97

0.96

n.s.

0.93

0.91

0.93

0.92

n.s.

All occlusal

0.95

0.98

0.96

0.96

n.s.

0.95

0.95

0.94

0.95

n.s.

p-value

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

Proximal

Maxillary C

0.99

0.99

0.99

0.99

n.s.

0.99

1.00

0.99

1.00

n.s.

surfaces*

Mandibular C

1.00

1.00

0.97

1.00

n.s.

0.99

1.00

1.00

1.00

n.s.

Maxillary D

0.99

0.98

0.99

0.98

n.s.

0.90

0.92

0.90

0.91

n.s.

Maxillary E

0.99

0.99

0.99

0.99

n.s.

0.93

0.94

0.92

0.93

n.s.

Mandibular D

0.99

0.98

0.96

0.99

n.s.

0.89

0.91

0.93

0.90

n.s.

Mandibular E

0.99

0.99

0.98

0.98

n.s.

0.90

0.86

0.91

0.91

n.s.

All proximals

0.99

0.99

0.98

0.99

n.s.

0.94

0.93

0.93

0.93

n.s.

p-value

n.s.

n.s.

n.s.

n.s.

n.s.

n.s

n.s.

n.s.

n.s. = not significant.

*Number of surfaces assessed were the same as in Table 3.

which did not use bitewings will underestimate the caries prevalence by about 10 per cent. Pooterman and co-

workers18 also reported underestimation figures of between 1 to 12 per cent in the absence of bitewing radiography. On the other hand, other authors have reported that the use of bitewing radiography did not result in a significant increase in permanent dentition

caries experience rates in subjects under the age 12

years.19–21 As the majority of permanent teeth in

children under 12 years have been erupted for relatively


short periods of time and their proximal caries expe-rience was low, inclusion of bitewing radiography for epidemiological purposes for this age group of children

would yield only a minimal increase in caries rates over

the visual examination.9,10,22

Previous studies suggest that bitewing radiography has the greatest value in detecting caries in subjects with the highest susceptibility to caries. The present results support this hypothesis in that inclusion of bite-wing radiography in these high-caries risk children of

27

B Newman et al.

Table 5. Sensitivity of occlusal and proximal caries detection using visual-tactile and bitewing examinations at the non-restorative threshold

Primary tooth

Sensitivity

Visual-tactile

Bitewing

Y1

Y3

Y7

All

p-value

Y1

Y3

Y7

All

p-value

Occlusal

Maxillary D

0.71

0.47

0.83

0.64

surfaces

Maxillary E

0.83

0.75

0.74

0.80

Mandibular D

0.74

0.44

0.83

0.64

Mandibular E

0.80

0.47

0.68

0.67

All occlusal

0.78

0.52

0.74

0.70

p-value

n.s.

p < 0.001

n.s.

p = 0.025

Proximal

Maxillary C

0.75

0.85

0.60

0.76

surfaces

Mandibular C

0.33

0.80

1.00

0.56

Maxillary D

0.43

0.46

0.41

0.44

Maxillary E

0.42

0.42

0.40

0.42

Mandibular D

0.54

0.46

0.53

0.51

Mandibular E

0.40

0.18

0.68

0.33

All proximals

0.46

0.38

0.50

0.43

p-value

p < 0.001

n.s.

p < 0.001

p = 0.01

n.s.

0.60

0.77

0.50

0.65

n.s.

p = 0.025

0.57

0.53

0.63

0.57

n.s.

p < 0.001

0.74

0.61

0.75

0.69

n.s.

p < 0.001

0.71

0.65

0.71

0.69

n.s.

p < 0.001

0.70

0.63

0.67

0.65

n.s.

n.s.

p < 0.001

p < 0.001

n.s.

n.s.

0.65

0.39

0.60

0.55

p < 0.001

p < 0.001

0.89

0.60

0.00

0.69

p < 0.001

n.s.

0.92

0.84

0.91

0.89

n.s.

n.s.

0.89

0.93

0.93

0.91

n.s.

n.s.

0.96

0.91

0.82

0.93

p = 0.01

n.s.

0.93

0.95

0.86

0.89

n.s.

n.s.

0.92

0.89

0.86

0.90

n.s.

p < 0.001

p < 0.001

p < 0.001

p = 0.025

Table 6. Specificity of occlusal and proximal caries detection using visual-tactile and bitewing examinations at the non-restorative threshold

Primary tooth

Specificity

Visual-tactile

Bitewing

Y1

Y3

Y7

All

p-value

Y1

Y3

Y7

All

p-value

Occlusal

Maxillary D

0.95

0.98

0.96

0.97

n.s.

0.96

0.96

0.99

0.96

n.s.

surfaces*

Maxillary E

0.89

0.96

0.94

0.93

n.s.

0.96

0.98

0.96

0.97

n.s.

Mandibular D

0.95

0.96

0.94

0.96

n.s.

0.95

0.94

0.96

0.95

n.s.

Mandibular E

0.91

0.94

0.94

0.93

n.s.

0.93

0.91

0.94

0.92

n.s.

All occlusal

0.93

0.96

0.94

0.94

n.s.

0.95

0.95

0.96

0.95

n.s.

p-value

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

Proximal

Maxillary C

0.99

0.99

0.99

0.99

n.s.

0.99

1.00

0.99

1.00

n.s.

surfaces*

Mandibular C

1.00

1.00

0.97

1.00

n.s.

0.99

1.00

1.00

1.00

n.s.

Maxillary D

0.98

0.97

0.99

0.98

n.s.

0.89

0.91

0.90

0.90

n.s.

Maxillary E

0.99

0.99

0.99

0.99

n.s.

0.92

0.93

0.92

0.92

n.s.

Mandibular D

0.99

0.98

0.96

0.99

n.s.

0.88

0.90

0.93

0.89

n.s.

Mandibular E

0.99

0.99

0.98

0.98

n.s.

0.89

0.85

0.92

0.90

n.s.

All proximals

0.99

0.99

0.98

0.99

n.s.

0.93

0.93

0.93

0.93

n.s.

p-value

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s.

n.s. = non-significant.

*Number of surfaces assessed were the same as in Table 3.

approximate mean ages of 6 and 8 years, reveals a significant increase of dmft of approximately 0.6–0.8 and dmfs of 1.3. These differences represent significant increases of around 20 per cent in both dmft and dmfs for almost all age groups when bitewing radiography was employed compared to the visual-tactile examina-tion alone. The present data, therefore, suggest that previous studies that did not include radiographs were likely to have significantly under-reported the caries experience of the primary dentition in children with high caries rates.

As in the permanent dentition, the sensitivity and specificity of detection methods for occlusal and proximal lesions of the primary dentition is likely to depend on

whether a cavitation (restorative) or non-cavitation threshold level is used for caries detection.

28

In an in vitro study, Lussi23 reported that the sensitivity for detection of occlusal caries using a visual-tactile examination increased from 14 per cent when a non-cavitation threshold was employed, compared to 82 per cent when a frank cavitation threshold was employed. Similarly, in the case of the bitewing examination, the non-cavitation threshold for caries was associated with only 45 per cent detection compared to 79 per cent when a cavitation threshold was used. These figures are supported

by the studies of Verdonschot and co-workers24 who also

noted that frank cavitation significantly increased diagnostic sensitivity of the visual-tactile technique.

As previous studies have reported that inclusion or non-inclusion of cavitated lesions can impact on occlusal caries detection, it is of interest to note


differences in sensitivity and specificity of the visual-tactile and bitewing radiography techniques when a restorative threshold is employed compared to when a non-restorative threshold is employed. In the present study, the criteria used for caries detection at the restorative threshold are those generally used for making a clinical decision for determining need for restorative treatment for the present cohort of children, who have relatively high caries risk. When such a restorative threshold was employed, the radiographic technique was more sensitive in detecting early occlusal caries compared to the visual-tactile technique. The present findings are thus supported by previous in vitro studies which reported similar trends in

extracted teeth.4

The prevalence rate of occlusal caries which cannot

be detected by visual-tactile examination alone, or

‘‘hidden’’ caries3,25–27 is found by the difference in

sensitivity values between the visual-tactile and radio-graphic techniques. The present finding of a prevalence of occlusal hidden caries of 12 per cent suggests that a significant number of occlusal caries lesions in the primary dentition will be missed if bitewing radio-graphs are not exposed. While the occurrence rates of hidden caries in the permanent dentition have been reported to be around 4–50

per cent in adolescents and young adults,3,25 the prevalence of this condition in the primary dentition has not been reported before. To the authors’ knowledge, the present study thus provides the first in vivo data of the prevalence rate of ‘‘hidden’’ occlusal caries in the primary dentition.

Proximal surface caries are well known to be more difficult to detect using a visual-tactile technique compared to occlusal lesions. Hence it is not surprising that the present study reveals that sensitivity of the visual-tactile technique for detecting proximal lesions was only 0.43. By contrast, bitewing radiography gave a sensitivity value twice as high, which suggests that the majority of proximal lesions at the restorative threshold will be detected by bitewing radiography.

In contrast to sensitivity, the specificity of both visual-tactile and bitewing techniques for primary molars are consistently high with all values greater than 90 per cent for both occlusal and proximal lesions. While there are no previous similar studies on primary teeth, comparisons with the permanent dentition showed similar high

specificity values.28–33 The present data thus suggest that both visual-tactile and bitewing techniques have high accuracy in detecting the absence of caries in the primary dentition of both occlusal and proximal surfaces at the restorative level.

The present results support the recommendations of paediatric dentistry worldwide that bitewing radiogra-phy be considered part of the routine initial dental examination of children who are old enough to cooperate and have proximal surfaces that cannot be



visualized.34,35 For recall examinations, the frequency of bitewing radiographs is usually tailored to the individual’s caries risk as determined clinically.

CONCLUSIONS

At the restorative threshold, for primary molar prox-imal surface caries, the visual-tactile technique detected only 43 per cent of lesions compared with 91 per cent for bitewing radiography. For occlusal caries, the visual-tactile technique detected 62 per cent of lesions compared to 74 per cent for bitewing radiography. The prevalence of ‘‘hidden’’ occlusal caries which is detect-able only by radiography is approximately 12 percent.

REFERENCES

Bader JD. A systematic review of the performance of methods for identifying carious lesions. J Public Health Dent 2002;62:201– 213.

Cortes DF, Ekstrand KR, Elias-Beneta AR, Ellwood RP. An in vitro comparison of the ability of fibre-optic transillumination, visual inspection and radiographs to detect occlusal caries and evaluate lesion depth. Caries Res 2000;34:443–447.

Kidd EA, Naylor MN, Wilson RF. The prevalence of clinically undetected and untreated molar occlusal dentine caries in ado-lescents on the Isle of Wight. Caries Res 1992;26:397–401.

Ketley CE, Holt RD. Visual and radiographic diagnosis of occlusal caries in first permanent molars and in second primary molars. Br Dent J 1993;174:364–370.

Ismail AI. Clinical diagnosis of precavitated carious lesions. Community Dent Oral Epidemiol 1997;25:13–23.

Downer MC. Validation of methods of caries diagnosis. Int Dent J 1989;39:241–246.

Chong MJ, Seow WK, Purdie DM, Cheng E, Wan V. Visual-tactile examination compared with conventional radiography, digital radiography and Diagnodent in the diagnosis of occlusal hidden caries in extracted premolars. Paediatr Dent 2003;2:314– 319.

Ricketts DN, Kidd EA, Wilson RF. A re-evaluation of electrical

resistance measurements for the diagnosis of occlusal caries. Br Dent J 1995;178:11–17.

World Health Organization. Oral health surveys: basic methods. 4th edn. Geneva: WHO, 1997.

Richardson PS, McIntyre IG. The difference between clinical and bitewing detection of approximal and occlusal caries in Royal Air Force recruits. Community Dent Health 1996;13:65–69.

Kidd EA, Pitts N. A reappraisal of the value of the bitewing

radiograph in the diagnosis of posterior approximal caries. Br Dent J 1990;169:195–200.

Fracaro MS, Seow WK, McAllan LH, Purdie DM. The sensitivity and specificity of clinical assessment compared with bitewing radiography for detection of occlusal dentine caries. Paediatr Dent 2001;23:204–210.

Hintze H. Screening with conventional and digital bitewing radiography compared to clinical examination alone for caries detection in low risk children. Caries Res 1993;27:499–504.

Stamm JW, Disney JA, Graves RC, Bohannan HM, Abernathy JR. The University of North Carolina Caries Risk Assessment Study. I: Rationale and content. J Public Health Dent 1988;48: 225–232.

Cohen JA. A coefficient of agreement for nominal scales. Educ Psych Meas 1960;20:37–46.

29

B Newman et al.

Seow WK. Pre-eruptive resorption as an entity of occult caries. Paediatr Dent 2000;22:370–376.

Hopcraft MS, Morgan MV. Comparison of radiographic and clinical diagnosis of approximal and occlusal dental caries in a young adult population. Community Dent Oral Epidemiol 2005;33:212–218.

18. Poorterman JH, Aartman IH,

Kieft JA, Kalsbeek H. Value

of bitewing radiographs in a

clinical epidemiological study

and their effect on the DMFS index. Caries Res 2000;34:159– 163.

Ruiken HM, Truin GJ, Konig KG. Feasibility of radiographical diagnosis in 8-year-old schoolchildren with low caries activity. Caries Res 1982;16:398–403.

de Vries HC, Ruiken HM, Ko¨nig KG, van’t Hof MA. Radio-graphic versus clinical diagnosis of approximal carious lesions. Caries Res 1990;24:364–370.

Machiulskiene V, Nyvad B, Baelum V. A comparison of clinical and radiographic caries diagnosis in posterior teeth of 12-year-old Lithuanian children. Caries Res 1999;33:340–348.

Mitropoulos C, Holloway PJ, Davies T, Worthington HV. Relative efficacy of dentifrices containing 250 or 1000 ppm F- in preventing dental caries: report of 32 month trial. Community Dent Health 1984;1:193–200.

Lussi A. Impact of including or excluding cavitated lesions when evaluation methods for the diagnosis of occlusal caries. Caries Res 1996;30:389–393.

Verdonschot EH, Bronkhorst EM, Burgersdijk RCW. Perfor-mance of some diagnostic systems in examinations for small occlusal carious lesions. Caries Res 1992;26:59–64.

Weerheijm KL, Groen HJ, Bast AJJ. Clinically undetected occlusal dental caries: a radiographic comparison. Caries Res 1992;26:305–309.

Seow WK, Wan A, McAllan L. The prevalence of dentine radiolucencies in the permanent dentition: a analysis of bitewing radiographs. Pediatr Dent 1999;21:26–33.

Seow WK, Lu PC, McAllan L. Prevalence of pre-eruptive in-tracoronal dentine defects from panoramic radiographs. Pediatr Dent 1999;21:332–339.

Downer MC. Concurrent validity of an epidemiological diag-nostic system for caries with histological appearance of extracted teeth validating criterion. Caries Res 1975;9:231–246.

Mejare I, Grondahl HG, Carlstedt K, Grever AC, Ottosson E. Accuracy at radiography and probing for the diagnosis of prox-imal caries. Scand J Dent Res 1985;93:178–184.

Lussi A. Comparison of different methods for the diagnosis of fissure caries without cavitation. Caries Res 1993;27:409–416.

Hintze H, Wenzel A. Diagnostic outcome of methods frequently used for caries validation. A comparison of clinical examination, radiography and histology following hemisectioning and serial tooth sectioning. Caries Res 2003;37:115–124.

Rocha RO, Ardenghl TM, Olive RA, Rodrigues CR, Ciamdon AC. In vivo effectiveness of laser fluorescence compared to visual inspection and radiography for detection of occlusal caries in primary teeth. Caries Res 2003;37:437–441.

Ashley P. Diagnosis of occlusal caries in primary teeth. Int J Paediatr Dent 2000;10:166–171.

Reference Manual. American Academy of Pediatric Dentistry 2007, p 222.

Standards of Care Manual. Australasian Academy of Paediatric Dentistry, 2008.

Address for correspondence: Dr W. Kim Seow School of Dentistry

The University of Queensland 200 Turbot Street Brisbane QLD 4000 Email: [email protected]


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