Approximal Carious Lesions Research Articles

In vitro Comparison of D- and E-Speed Film Radiography, RVG, and Visualix Digital Radiography for the Detection of Enamel Approximal and Dentinal Occlusal Caries Lesions

The aims of this study were (1) to compare the accuracy of conventional D- and E-speed film radiography and direct digital radiography using the RadioVisioGraphy and Visualix systems for the detection of enamel approximal caries lesions and (2) to compare the accuracy of D- and E-speed films and the Visualix system for the detection of dentinal occlusal caries lesions. In total, 122 approximal surfaces were examined in vitro by 3 observers and 65 occlusal surfaces by 2 observers. The true caries diagnosis was based on histological assessment of the surfaces after sectioning the teeth. Approximal surfaces were deemed diseased by the presence of a demineralization in enamel, while occlusal surfaces were deemed diseased by the presence of a demineralization into dentine. The diagnostic accuracy for each radiographic method was expressed as a receiver operating characteristic (ROC) curve area. For the approximal surfaces, the areas under the ROC curves ranged from 0.53 (Visualix) to 0.70 (E-speed film). For the occlusal surfaces, the areas ranged from 0.62 (Visualix) to 0.79 (D- and E-speed films). No statistically significant differences between mean ROC curve areas for the radiographic methods were found either for the approximal or for the occlusal surfaces. It was concluded that radiography was of almost no value in the detection of enamel approximal caries lesions, but of some value in the detection of dentinal lesions in occlusal surfaces.

Progression of approximal caries in relation to iatrogenic preparation damage.

The aim of the present study was to evaluate the effect of iatrogenic preparation damage on the need for operative caries treatment of approximal surfaces, adjacent to Class II amalgam restorations. The material was collected by 77 dentists from the Public Dental Child Health Service in Denmark. It consisted of die-stone models of 187 first-time Class II preparations, adjacent to 190 unfilled approximal surfaces of 58 primary and 132 permanent teeth. The cavity preparations were performed in children between 4 and 17 years of age. They were all filled with amalgam. Information about operative treatment and exfoliation or extraction of the preparation teeth and the adjacent teeth during the following seven years was obtained from the patients' records. Stereomicroscopic examination of the models revealed preparation damage on 64% of the unfilled approximal surfaces in primary teeth and on 69% of the corresponding test surfaces in permanent teeth. During the observation period, operative treatment was performed on 10% of the undamaged test surfaces in primary teeth and on 35% of the damaged ones (p less than 0.05). The corresponding figures for test surfaces in permanent teeth were 6% and 15% (p less than 0.05). It is concluded that iatrogenic preparation damage is a frequent side-effect of operative intervention with approximal caries lesions, and represents a dental health problem, since the damage increases caries progression and the perceived need for restorative therapy of the adjacent teeth.

Computer-based image analysis of natural approximal caries on radiographic films.

This paper reports on the development of computer software for automatic detection and measurement of approximal caries lesions on digital images obtained from radiographic films. If the program detects a lesion, it defines the lesion's border and measures and reports these lesion parameters: percent mineralization, area, maximum enamel penetration, and mean enamel penetration. Two experiments are reported; both were conducted with the use of extracted human premolar teeth. In the first experiment, thin sections were obtained from 13 approximal surfaces with caries lesions. Microradiographs were made of the sections, and software measurements of the lesions were obtained from the microradiographs. The software was able to separate the lesions into two groups: those that had penetrated less than 100% of the enamel and those that had penetrated 100% of the enamel. The software measurements agreed with evaluation of lesion penetration by polarized light microscopy of the thin sections. In the second experiment, simulated clinical radiographs were made of 16 approximal surfaces, 12 with lesions and four without. Thin sections were obtained for microradiography. Software was used for automatic detection and measurement of the lesions on both types of film. The ability of the software to detect the lesions on the clinical films was compared with that of 10 experienced clinicians. Correlations of the same parameter from the two types of radiographic films were statistically significant, 0.86 less than or equal to r less than or equal to 0.95 and p less than 0.05. The coefficients of variation were low for both microradiographs, 0.4-2.3%, and for clinical films, 0.7-8.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of digital grey-scale modification on the diagnosis of small approximal carious lesions

The aim of this study was to evaluate the accuracy of approximal caries diagnosis from digitized radiographs and digitally modified radiographic images, compared with conventional radiography. Twenty bitewing radiographs were digitized and from the digitized radiographs mirror-images were produced, resulting in 40 digital images. The caries progress at three approximal surfaces was graded by 12 dentists from conventional radiographs, digital unmodified images and digitally modified images. The image modifications were derived from the cumulative probability of grey values in the original digital image using one of five probability distributions: uniform, exponential, Rayleigh, hyperbolic cube root and hyperbolic logarithmic. Interobserver agreement was substantial. The unmodified digital images produced sensitivities comparable to radiographs but their specificities were lower. When the diagnostic task was to discriminate between ‘caries’ and ‘no caries’, the exponential, hyperbolic cube root and hyperbolic logarithmic modifications and radiographs performed equally well. With the decision cut off between ‘dentinal caries’ and ‘no dentinal caries’, the sensitivity of the hyperbolic logarithmic type of modification was statistically significantly superior to that of radiographs, but this modification was also associated with a statistically significant reduction of specificity. It is concluded that in particular the hyperbolic logarithmic modification can be an alternative to conventional radiography in incipient approximal caries diagnosis and restorative decision making.

Approximal caries diagnosis using fiber‐optic transillumination: a mathematical adjustment to improve validity

Several studies were conducted recently to evaluate the use of Fiber-Optic Trans-Illumination (FOTI) in the diagnosis of approximal carious lesions. All these studies utilized radiographic readings to validate the FOTI diagnoses. Other investigations studied the value of radiographic readings using more solid validating techniques, which made it possible to judge the true state of decay, such as histology, cavity preparation and microradiography. In this study, data from both types of studies were used to estimate the validity of FOTI diagnosis of approximal caries relative to the true status of decay through correction for radiographic misclassification. The results indicate that particularly the sensitivity of FOTI diagnosis has yet to be determined.

Effect of Different Fluoride Levels in Dentifrice on the Development of Approximal Caries

The development of approximal carious lesions was monitored on annual bite-wing radiographs obtained from 315 children, participating in a controlled dentifrice trial; 157 of these children had used a dentifrice containing 250 ppm F and 158 a dentifrice containing 1,000 ppm F (both as NaF) during a 3-year period as the sole fluoride supplement. The total number of surfaces recorded was 6,099 at the baseline and 7,358 at the final examination. In the 250-ppm F group 393 approximal lesions (297 in the outer half, 96 in the inner half of the enamel) and in the 1,000-ppm F group 399 lesions (319 and 80, respectively) were diagnosed at the baseline examination. After 3 years the fraction of sound surfaces had decreased from 79% at baseline in both groups to 54% in the low-F group and to 58% in the high-F group. Concurrently, the relative number of enamel lesions had increased from 13% in both groups to 26% in the low-F group and 24% in the high-F group. 66% of the surfaces in the low-F group and 60% in the high-F group remained sound, and the relative proportion of static enamel lesions was 26 and 28%, respectively. The differences did not reach statistical significance. The results imply that higher fluoride levels in the dentifrice are more effective in retarding the initiation of caries, while they do not differ with respect to the progression of radiographically detectable approximal carious lesions.

Optical Quantitation and Radiographic Diagnosis of Incipient Approximal Caries Lesions

The objectives of this study were to test the applicability of photocell measurements in approximal caries diagnosis and to evaluate the use of radiographs as validating criterion. Forty extracted premolars were selected, and the progression of the approximal lesions was graded clinically and radiographically by three examiners. Each tooth was transilluminated from the occlusal surface, and the throughput of light at the approximal surface was measured by a photocell. Together with clinical examination, the results of microradiographic analysis served as validating criterion in this study. The results indicate that photocell measurements can be useful in the diagnosis of incipient approximal caries lesions. Radiographs have a restricted value as validating criterion in diagnostic studies pertaining to incipient caries.

Optical Quantification of Approximal Caries in vitro

A fluorescent dye was applied to extracted premolars with either early artificial lesions or natural white-spot lesions. The teeth were placed in an approximal geometry, and with a specially designed fibre-optic probe the fluorescence of the dye was measured in the lesions. The same fibre-optic probe was used to measure the transmission of light at a wavelength where the dye does not absorb. This transmission of light was used to correct the fluorescence for attenuation by the intermediate layer of sound enamel situated between the probe and the lesion. Both signals varied with time because of the necessary addition of ethanol during the measurement. The mineral loss from the lesions was measured with wavelength independent microradiography (WIM) for the artificial lesions, and the optical caries monitor (OCM) for the natural white-spot lesions. The correlation coefficient between corrected fluorescence and mineral loss was r = 0.86. The results indicate that measurement of dye uptake may be a very sensitive method to diagnose early approximal caries lesions and may enable quantification of these lesions.

The prevalence of clinically undetected occlusal dentine caries in Scottish adolescents

During the third examination of a 3-year anti-caries dentifrice study, bitewing radiographs were read to detect occlusal, as well as approximal caries lesions in 2623 subjects aged 14-15 years. These analyses showed that 1.4% of 2107 upper molars and 7.2% of 2288 lower molars (P less than 0.001), previously scored as clinically 'sound', were carious at a radiographic Grade '3' score (dentinal involvement), and 0.2% had radiographic pulpal lesions. However, for teeth which had been deemed as having a 'suspicion' of caries clinically, but which a 0.6 mm blunted probe would not enter, 29.1% of lower molars had definite radiographic evidence of dentinal caries as compared to only 7.6% of upper molars (P less than 0.001), and a further 0.5% exhibited pulpal extension. In addition, 23.9% of lower premolars also showed dentinal involvement in this group. Overall, 12.1% of lower molars and 3.1% of upper molars showed definite radiographic evidence of occlusal caries in the absence of a firm clinical indication. Thus, the use of bitewing radiographs would appear to be a most helpful adjunct to clinical caries diagnosis, not only of approximal lesions, but also for the detection of early occlusal caries, in these days of generally available topical fluoride.

Progression of posterior approximal carious lesions in Norwegian teenagers from 1982 to 1986

The purpose of the present study was to assess the progression rate of approximal carious lesions in Norwegians aged 14-18 years. Sixty-five subjects whose average age at base line was 14.9 years had one pair of posterior bitewing radiographs taken annually from 1982 to 1986. One examiner assessed all radiographs in chronologic order, recording degree of approximal caries. When a surface changed from one state to another, it was assumed to have changed at the midpoint between the two examinations. A total of 590 lesions were observed. Uncensored lesions took on average nearly 3 years to penetrate the enamel. Inclusion of right censored lesions by the Kaplan-Meier approach increased the uncensored estimate by approximately 20%. The average for doubly censored lesions was about 6.5 years. Low average rate of caries progression coupled with wide variations between lesions and among subjects suggests a need for individually prescribed recall routines.

Microconservative Restorations for Approximal Carious Lesions

The availability of new restorative materials such as glass ionomers, which have an anticaries action, prompts a reevaluation of some of the basic principles of restorative dentistry. It seems that conventional methods of treating the approximal carious lesion are too radical and that microconservative techniques offer a simpler, more effective solution when correctly applied.

Radiographic versus Clinical Diagnosis of Approximal Carious Lesions

For school-age children, in whom caries activity has declined considerably, the efficiency of bitewing radiographs in diagnosing approximal lesions requires reevaluation. Therefore parallel clinical and radiographic examination of approximal surfaces were carried out in 317 14-year-old children. To assess the degree of agreement between both methods sensitivity and negative predictive value were determined. At the same time previously published data of children aged 8 through 12 years were reassessed. From the results it is concluded that omission of radiographic examination will not result in a substantial loss of information under the age of 12, but above this age it is advisable to include radiographic diagnosis for approximal surfaces.

Competition between Streptococcus mutans and Lactobacillus casei in mixed continuous culture

In natural oral ecosystems, succession of Streptococcus mutans and Lactobacillus species occurs in bacterial communities which can be associated with the development of carious lesions. The objective of this study was to explore the interaction between 2 strains of S. mutans (SF2452) and Lactobacillus casei (RB1014) when grown together in continuous culture under conditions of varying environmental pH and in the presence of fluoride. When the strains, isolated from approximal carious lesions, were grown initially at a dilution rate of 0.1 h-1 under a glucose limitation at pH 7.0, a stable mixed community developed (Days 5-10) with S. mutans as the dominant population. When the pH control was removed (Day 10), the binary culture lowered the pH to 5.1 causing a small reduction in the numbers of S. mutans and allowing L. casei to predominate. A more dramatic effect was seen when the environmental pH was rapidly lowered to 4.8 by the addition of acid. In this case, the S. mutans population was significantly reduced and the L. casei population rose to the level previously held by S. mutans. Re-adjustment of the pH to 7.0 resulted in a re-establishment of the population ratios prior to the addition of acid. The possibility that S. mutans was capable of aciduric adaptation during a biologically-generated pH reduction was examined by mixing cultures of both organisms after each had been grown to steady state at pH 5.5 in separate chemostats.

Quantification of incipient approximal caries during fructose and sucrose consumption

The purpose of this study was to quantify the changes in the size of approximal caries lesions during regular sucrose or fructose consumption. The material consisted of the subjects in the 2-year Turku Sugar Study, with an observation period of 19 months. Planimetric evaluation showed a highly significant increase in the approximal lesions of both groups. There was no difference between the groups in the rate of the increase in the sizes of the lesions. Initially, small lesions increased at a higher rate than initially large lesions in both groups. It is concluded that a fructose diet enhances the progression of carious lesions as much as a sucrose diet.

Monitoring the behaviour of posterior approximal carious lesions by image analysis of serial standardised bitewing radiographs'

Monitoring the behaviour of posterior approximal carious lesions by image analysis of serial standardised bitewing radiographs'

Monitoring the behaviour of posterior approximal carious lesions by image analysis of serial standardised bitewing radiographs.

Monitoring the behaviour of posterior approximal carious lesions by image analysis of serial standardised bitewing radiographs.

Approximal caries development during 2-year total substitution of dietary sucrose with xylitol.

The purpose of the present study was to quantify changes in the size of approximal carious lesions in order to find out the effect of sucrose or xylitol consumption on the rate of caries progression. The projections of approximal lesions on bite-wing radiographs were analysed planimetrically. Evaluation of the data showed a highly significant increase of approximal lesion size in the sucrose group; in the xylitol group lesion sizes remained unchanged. The corresponding difference in lesion size between the xylitol and sucrose groups after the 2-year study period was highly significant (p < 0.001). It is concluded that sucrose consumption ad libitum enhances the further progress of carious lesions, whereas xylitol consumption favours the arrest and decrease of the lesions.

Radiographic and observed tissue changes in approximal carious lesions at the time of operative treatment.

Clinical tissue changes in 1,080 approximal carious lesions at the time of operative treatment were recorded by 263 Danish dentists. The findings were related to type of tooth, age of the patient, and

The expected benefits from alternative frequencies of bitewing radiograms.

From an analysis of serial bitewing radiograms, we have developed a mathematical model of the initiation and progression of approximal carious lesions in the permanent teeth. The model is used to estimate the expected number of lesions, per individual, not detected until they reach the inner half of the dentin, as a function of the frequency with which radiograms are taken between the ages of 8 and 20 years. If radiograms are performed every 6 months and lesions not restored until radiolucencies appear in the dentin, under 5% of all lesions developing over the 12-year period will reach the inner half of the dentin before detection. If radiograms are taken every 2 years, about 18% of all lesions will have reached the inner half of the dentin before detection. The sensitivity of these conclusions to different assumptions is examined.

Regression of approximal carious lesions diagnosed from serial standardized bitewing radiographs.

Regression of approximal carious lesions diagnosed from serial standardized bitewing radiographs.