Z J Nugent

The fate of 1,587 unrestored carious deciduous teeth: a retrospective general dental practice based study from northern England

Objective To investigate the outcome of non-restoration of carious deciduous teeth by means of a retrospective analysis of clinical case notes of children regularly attending two general dental practices and receiving preventive care.Design Using a carefully defined protocol the fate of deciduous teeth diagnosed as carious into dentine but symptomless and left unrestored was determined from the sequential examination of the clinical records of 481 children attending at least annually.Results The age at initial diagnosis of carious teeth ranged from 1–12 years with the majority of cavities (1,005) presenting by 6 years of age. In all, 1,587 teeth were followed until loss from the mouth. Of these, 190 (12%) were extracted because of pain and a further 60 (4%) became painful and were treated, leaving 1,337 (84%) that remained symptomless until being lost. Of the 1,337 symptomless teeth, 178 were extracted under general anaesthesia at the same time as painful ones. The final group of 1,159 (74%) teeth were exfoliated without causing pain after a mean survival time of 1,332 days. Excluding from the analysis the 178 extracted, but symptomless teeth, leaves a total of 1,409 teeth of which 18% gave pain and were extracted or treated and the remaining 82% exfoliated. The strongest determinant of pain was age on diagnosis, the other factors being tooth type and extent of the cavity when first seen. The carious teeth most likely to cause symptoms were found to be molars that developed cavities with pulpal involvement by the age of 3 years, 34% of which caused pain. In contrast, those least likely to cause pain were carious molar teeth presenting without pulpal involvement after 8 years, only 6% of which produced symptoms.Conclusion In these patients, the majority of unrestored carious deciduous teeth remain symptomless until shed. The results provide evidence to aid the treatment planning of carious deciduous teeth in children regularly receiving regular preventive dental care.

Validity and Reproducibility of ICDAS II in Primary Teeth

The aim of this in vitro study was to assess the validity and reproducibility of the ICDAS II (International Caries Detection and Assessment System) criteria in primary teeth. Three trained examiners independently examined 112 extracted primary molars, ranging from clinically sound to cavitated, set up in groups of 4 to mimic their anatomical positions. The most advanced caries on the occlusal and approximal surfaces was recorded. Subsequently the teeth were serially sectioned and histological validation was undertaken using the Downer and Ekstrand-Ricketts-Kidd (ERK) scoring systems. For occlusal surfaces at the D1/ERK1 threshold, the mean specificity was 90.0%, with a sensitivity of 75.4%. For approximal surfaces, the specificity and sensitivity were 85.4 and 66.4%, respectively. For occlusal surfaces at ICDAS code ≥3 (ERK3 threshold), the mean specificity and sensitivity were 87.0 and 78.1%, respectively. For approximal surfaces, the equivalent values were 90.6 and 75.3%. At the D3 threshold for occlusal surfaces, the mean specificity and sensitivity were 92.8 and 63.1%, and for approximal surfaces 94.2 and 58.3%, respectively. Mean intraexaminer reproducibility (Cohen’s kappa) ranged from 0.78 to 0.81 at the ICDAS code ≥1 cut-off and at the ICDAS code ≥3 cut-off from 0.74 to 0.76. Interexaminer reproducibility was lower, ranging from 0.68 to 0.70 at the ICDAS code ≥1 cut-off and from 0.66 to 0.73 at the ICDAS code ≥3 cut-off. In conclusion, the validity and reproducibility of the ICDAS II criteria were acceptable when applied to primary molar teeth.

A Randomised Controlled Trial of the Caries– Preventive Efficacy of a Chlorhexidine–Containing Varnish in High–Caries–Risk Adolescents

A professionally applied two–stage chlorhexidine varnish, Chlorzoin®, was developed to achieve sustained release and minimise the problems of staining and bad taste associated with chlorhexidine mouthrinses. The primary aim of this randomised controlled clinical trial was to assess the efficacy of Chlorzoin in reducing the caries increment in high–caries–risk adolescents. Secondary aims included investigating the effect of compliance upon caries increment, the effect of Chlorzoin upon salivary mutans streptococci levels and assessing the benefit of individual dental health advice by dental auxiliaries in a community setting. 1,240 children, initially aged 11–13 years, assessed to be at high caries risk were recruited into the trial. The trial design involved four arms: an observational group, a control group, an active (Chlorzoin) varnish group and a placebo varnish group. All subjects were examined annually by a calibrated examiner who was blind to the group allocation. Three–year caries increments were calculated using clinical, clinical and fibre–optic transillumination, and clinical and bitewing data sets. The results indicated that the use of Chlorzoin had an initial effect on mutans streptococci levels but that no long–term reduction in caries increment or mutans streptococci infection could be detected. One reason for this lack of efficacy may have been the regimen of reduced frequency of varnish applications after the initial period. Children who followed the protocol and, therefore, were seen regularly by dental auxiliaries had a lower caries increment than those who did not. This finding was independent of varnish allocation. In summary, under this regimen, Chlorzoin has been found to be effective in decreasing salivary mutans streptococci but ineffective as a caries–preventive agent in high–risk Scottish children when applied pragmatically in a community setting.

The Effect of Placing a Clear Pit and Fissure Sealant on the Validity and Reproducibility of Occlusal Caries Diagnosis

The purpose of this in vitro study was to assess the validity and reproducibility of the diagnosis of fissure caries prior to and following the placement of a clear sealant. One hundred and twelve extracted molar teeth were examined by 7 experienced clinicians. Each examiner conducted four visual examinations, 2 prior to and 2 after sealing, allowing an assessment of reproducibility. The teeth were subsequently serially sectioned to provide the histological validation. After placement of a sealant, a significant (p < 0.05) loss of sensitivity was found for the diagnosis of enamel lesions and dentine lesions, but specificity was not altered. The overall reproducibility expressed by the kappa statistic was 0.60 and 0.47, before and after sealing, respectively. The examiners significantly (p < 0.001) underestimated the severity of lesions detected after sealing compared to their assessment prior to sealing. The investigation suggests that sealed surfaces require careful assessment and monitoring.

Accuracy and Reproducibility of Conventional Radiographic Assessment and Subtraction Radiography in Detecting Demineralization in Occlusal Surfaces

Subjective interpretation of paired digital radiographic images viewed side by side to assess occlusal lesion progression, arrest or remineralization is difficult. The aim of this study was to compare the accuracy and reproducibility of a digital subtraction radiography technique and visual assessment of paired digital images in detecting changes in mineral content within occlusal cavities. Forty molar teeth with occlusal cavities were placed in arches and baseline digital radiographs taken. Nineteen teeth were randomly selected and had acid placed in the cavities and digital images taken after 3, 6, 12, 18 and 24 h of acid exposure. Paired baseline images and those taken at the various time intervals were examined side by side and assessed for demineralization by five examiners. Subtraction images prepared from the paired images were assessed in the same way. One fifth of the images were re-examined to determine intra-examiner reproducibility. After 12 h or longer the diagnostic accuracy (mean area under the ROC curve = 0.92–0.98 for subtraction radiography), intra-examiner and inter-examiner reproducibility for detection of demineralization from the subtraction images was significantly better than viewing the paired images side by side (p < 0.01). The subtraction radiography system used was found to be more accurate and reproducible than visual assessment of paired digital images. As such the technique shows promise for monitoring occlusal lesion progression in clinical studies.

Relationships between a clinical-visual scoring system and two histological techniques: a laboratory study on occlusal and approximal carious lesions.

One aim of the present laboratory study was to determine whether a visual scoring system (ERK) developed for occlusal caries could be applied to approximal lesions. A new histological technique (autofluorescence, AF) recognises dentine that is soft and would be removed with an excavator during operative treatment. A second aim was to investigate the relationship between the visual scoring system (ERK) and AF of dentine both occlusally and approximally. The sample comprised 93 extracted teeth chosen to represent the range of visual scores on approximal and occlusal surfaces. After sectioning through the investigation site, the cut faces were examined in a stereomicroscope and the depth of demineralization was scored. Autofluorescence was viewed with a confocal laser scanning microscope. Results showed reasonable correlation between the visual scores and the stereomicroscope histological evaluations for occlusal surfaces and non-cavitated approximal surfaces. However, cavitated approximal surface lesions were less advanced histologically than cavitated occlusal carious lesions. The AF technique indicated that several lesions with intact surfaces would have had soft, excavatable dentine, whereas several with microcavities would not.

Restorative dentistry: A clinical evaluation of an Erbium:YAG laser for dental cavity preparation

Objective A randomised controlled trial to determine the acceptability to dentists and patients of cavity preparation with an Erbium:YAG laser as compared with conventional handpieces.Methods Fifteen dentists (9 GDPs, 1 community dentist and 5 hospital dentists) treated 77 patients (age range 3.5–68 years old) who had two matched cavities, in a split mouth, randomised trial. One cavity was prepared conventionally, the other with the laser, with dentist and patient preference determined by questionnaire.Results In the majority of cases, where dentists expressed a preference, it was for conventional cavity preparation, and this was significant (p < 0.001). In more than half of the laser appointments, dentists had to use conventional handpieces to complete the cavity. Principle difficulties reported with the laser were access (25 cases) and slow speed of cutting (11 cases). Patients aged ≥10 years who expressed a preference, preferred laser treatment, and this was significant (p < 0.001). Patients aged <10 years, assessed using a simplified pictorial questionnaire, did not show a significant preference for either technique.Conclusions Dentists preferred conventional handpieces for cavity preparation while patients aged ≥10 years old preferred laser treatment. Patients <10 years old did not express a preference.

Effect of Placing a Clear Sealant on the Validity and Reproducibility of Occlusal Caries Detection by a Laser Fluorescence Device: An in vitro Study

The principal aim of this in vitro study was to assess the validity and reproducibility of the detection of occlusal caries using laser fluorescence (LF), prior to and following the placement of a clear fissure sealant. It also aimed to compare the manufacturer’s standard cut-off recommendations with those published for in vitro studies and to compare the validity and reproducibility of LF with clinical visual examination (CVE) for the detection of occlusal caries under sealants. Three clinicians independently examined visually and with LF 37 extracted teeth (25 molars, 12 premolars), with a range of clinical caries from apparently sound to cavitated dentinal caries. Examinations were conducted under dental surgery conditions. Subsequently, the teeth were serially sectioned to provide the validating criterion. Following placement of the sealant, the specificity generally increased but there was an associated loss of sensitivity, at both the D1 (enamel and dentine) and D3 (dentine) diagnostic thresholds. The LF readings were significantly lower after placement of the sealant (p < 0.05). The manufacturer’s recommended cut-offs appear to be the most appropriate to use. The CVE had superior validity and reproducibility when compared to LF. Overall, the placement of a clear sealant does influence the detection of caries by LF but does not prevent the detection of caries by this method.

Does social deprivation in 1, 2, 3 and 4-year-old Scottish infants influence the frequency isolation of caries-associated micro-organisms?

OBJECTIVES The aim of this study was to determine if there are associations between the level of social deprivation/affluence and the frequency isolation of caries-associated micro-organisms (Streptococcus mutans, Streptococcus sobrinus, lactobacilli and yeasts) in a large cohort of infants examined annually from 1 to 4 years of age. METHODS DEPCAT was used to measure the socio-economic status of all consented infants (n=1099--1392) born in Dundee during a 1 year period (total n=1974). Caries-associated micro-organisms were cultured from saliva when the infants were 1, 2, 3 and 4 years of age. Standardised dental examinations were also carried out annually. Log linear analysis, which controlled for caries, was used to look for associations between DEPCAT and the isolation frequency of caries-associated micro-organisms. RESULTS When controlling for caries, there was an association between DEPCAT and the isolation frequency of yeasts when the infants were 1 and 2 but not when 3 and 4 years old, whereas lactobacilli were associated only when the infants were 3 and 4 years old. Correlations between S. mutans and social deprivation were usually dependent on the caries status of the infants. CONCLUSIONS The relationship between social deprivation and the isolation frequencies of caries-associated micro-organisms is complex with lactobacilli developing an association when the infants were 3 and 4 years old in contrast to yeasts which were only associated when the infants were 1 and 2 years old. Streptococcus mutans was associated with social deprivation when the infants were 2 years old and older, but dependent on caries status in the 3 and 4 year olds.

A proposed method for assessing the quality of sealants – the CCC Sealant Evaluation System

OBJECTIVES The aim of this paper is to introduce the C (colour) C (coverage) C (caries) Sealant Evaluation System and to present results of its use on a sample of adolescent patients in Scotland. METHODS Baseline data are presented from a 3-year prospective study in general dental practices across Scotland. Subjects were examined under standardised conditions by one trained and calibrated examiner. RESULTS 78.6% of the subjects had one or more sealed teeth, over half of these sealants being judged inadequate. There was a low prevalence of dentine caries associated with the sealed teeth (2.8%). The CCC sealant Evaluation System proved practical as demonstrated by its use during the project and had substantial intra-examiner reproducibility. CONCLUSIONS There was a high level of sealant provision; however, this provision may not be optimal in terms of both targeting of provision and sealant maintenance. The CCC sealant Evaluation System appeared to be a useful assessment tool for assessing sealed surfaces.