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Background: The effectiveness of finasteride and dutasteride in women with androgenetic alopecia has been the subject of debate., Aim: To evaluate the effectiveness of finasteride and dutasteride on hair loss in women with androgenetic alopecia over a period of 3 years., Methods: From a database containing systematically retrieved data on 3500 women treated for androgenetic alopecia between 2002 and 2012 with finasteride 1.25 mg or dutasteride 0.15 mg, a random sample stratified for age and type of medication was taken to yield 30 women in two age categories: below and above 50 years, and for both medications. Hair thickness of the three thinnest hairs was measured from standardized microscopic images at three sites of the scalp at the start of the treatment and after 3 years of continuous medication intake. The macroscopic images were evaluated independently by three European dermatologists/hair experts. The diagnostic task was to identify the image displaying superior density of the hair., Results: Both age categories showed a statistically significant increase in hair thickness from baseline over the 3-year period for finasteride and dutasteride (signed rank test, P=0.02). Hair thickness increase was observed in 49 (81.7%) women in the finasteride group and in 50 (83.3%) women in the dutasteride group. On average, the number of post-treatment images rated as displaying superior density was 124 (68.9%) in the finasteride group, and 118 (65.6%) in the dutasteride group. Dutasteride performed statistically significantly better than finasteride in the age category below 50 years at the central and vertex sites of the scalp., Conclusions: Finasteride 1.25 mg and dutasteride 0.15 mg given daily for 3 years effectively increased hair thickness and arrested further deterioration in women with androgenetic alopecia.

The objective of this study was twofold, namely to evaluate the effectiveness of a dental clinical practice guideline on the management of asymptomatic impacted lower third molars (i) on referral rates and (ii) on dentists' change in knowledge. A two-arm cluster randomized controlled trial, with pre- and post-test assessments, was conducted. A guideline was implemented by multifaceted interventions (i.e. feedback, reminders, and an interactive meeting). The effect was evaluated after 1 yr by repeating the baseline questionnaire and by monitoring the number of patients who were referred for removal of their asymptomatic impacted mandibular third molars. Instruments were questionnaires for detecting changes in knowledge, patient records, and panoramic radiographs. The knowledge of dentists regarding asymptomatic mandibular third molar management was found to increase significantly in the intervention group as compared to the control group. There was no statistically significant difference between the groups in guideline-consistent patient referral rates at the post-test assessment. It was concluded that the methodology employed for dissemination and implementation of a clinical practice guideline on asymptomatic mandibular third molar management improves dentists' knowledge on this topic and is effective in improving decision-making in simulated cases; however, no clinical effect was demonstrated.

Objectives: The aim of this study was to explore differences in behaviour (characteristics and opinions) among general dental practitioners (GDPs), using either a fixed (Fx) or an individualized recall interval (Iv) between successive routine oral examinations (ROEs)., Methods: In the year 2000, data were collected by means of a written questionnaire sent to a random stratified sample of 610 dentists of whom 521 responded, of which 508 (83%) were used for analysis., Results: Two groups of GDPs were distinguished based on their answer to the question: 'Do you apply for all patients a fixed recall interval between two successive ROEs?' Fifty-one per cent of the GDPs (n=257) applied Fxs for all patients, generally for a period of 6 months. Ivs were applied by 49% (n=251) of GDPs, depending on the determination of specific patient characteristics. Logistic regression analysis showed that GDPs applying Fxs also used fixed periods between successive bitewing radiographs for all patients. Furthermore, dentists applying Ivs required more time to conduct an ROE, partly because of a more extensive periodontal screening. GDPs applying Fxs, adhered more to the opinion that a fixed recall regime (every 6 months, as existed before 1995) should be re-introduced, whereas the GDPs in support of Ivs were more in favour to support the opinion that the ROE is 'an excellent instrument for effective, individualized oral care'., Conclusions: Dutch GDPs differ in the way they deal with the determination of recall interval frequency. These are also specific differences in performance and opinions regarding ROE. With the changing prevalence of oral diseases and the skewed distribution within populations, further research is advocated on consistent decision making to determine the most appropriate recall policy in preventing oral disease.

In The Netherlands the routine oral examination (ROE) can be characterized as an important tool in dental care. As a result of the changing prevalence of oral diseases of the Dutch population the content of the routine oral examination has changed over time. A representative survey among general dental practitioners has been carried out to investigate the professional performance in the routine oral examination. Participants consisted of a random, stratified sample of 619 dentists, of whom 521 (85%) responded. The Dutch general dental practitioners use the routine oral examination mainly for detecting dental caries and to asses the status of the restorations. About 50% of the responders use a standard recall interval for all patients whereas the other half takes individual patient factors into consideration when determining the recall interval. Both groups differ significantly on the variables: 'time spend on the routine oral examination', 'the amount of diagnostic activities', 'the registration in patient dental records' and 'the frequency of using bitewing radiographs'. In the perspective of quality of dental care a national reconsideration of the routine oral examination by professionals and patients is advocated. The instrument of choice would be the use of evidence-based clinical practice guideline development procedures.

The aim of this study was to compare 2 methods for developing a clinical practice guideline (CPG) on the management of asymptomatic, impacted mandibular third molars. Outcome measures were the mean time invested by the participants for each method, the quality of the CPGs measured using the Appraisal of Guidelines for Research and Evaluation (AGREE) indicator and observations of the group discussions. We used a national consensus procedure following the Rand modified Delphi procedure (2 panels) and a local consensus procedure (2 existing dental peer groups). The mean time spent was about equal for the 2 methods. The quality of the CPGs developed by the expert panels was higher than that of the CPGs developed by the dental peer groups. Observation indicated that all group processes were influenced by the chairperson. We concluded that the expert panel method is suitable for developing reliable CPGs on a national or regional level.

The aim of this study was to assess the effect of the provision of a clinical practice guideline (CPG) on dental students' decisions to remove asymptomatic, impacted lower third molars. All dental students, who in 2001 were in the 3rd, 4th or 5th (final) year of their study at the Nijmegen College of Dental Sciences, were invited to participate. A pre-test-post-test control group design was used. Given 36 patient cases, all dental students were asked to assess the need for removal of asymptomatic, impacted lower third molars. All pre-test respondents were randomly allocated to the control or intervention group. After the provision of a CPG to the intervention group, both groups were asked to assess the same cases again. Frequencies of decisions to remove the third molars were calculated. Chi-square tests and anova were used to test the influence of study year and gender on the drop-out rate and on the effect of the provision of a CPG on students' treatment decisions. The decrease in indications to remove third molars by the intervention group was statistically significant (P < 0.05). In the control group, no significant decrease was observed. It was concluded that the provision of a CPG significantly influences dental students' decision making about treatment in a third-molar decision task. Students who used the CPG showed more guideline-conformed decision making.

By conducting an oral examination, during radiographic examination and in treatment planning procedures dentists make numerous decisions. A dentist will be required to make his decisions explicit. Decision trees and decision analyses may play an important role. In a decision analysis, the probability of correct and incorrect decisions are multiplied by the utility of the decision outcomes. The treatment outcome with the highest expected utility should be selected. Complex decision tasks such as the estimation of an individual's caries risk or the diagnosis of bone disorders are currently available as computer applications. Also, a preliminary version of a computer programme which detects caries lesions from bitewing radiographs independent from the dentist has become available. It is expected that the applicability of decision analyses will increase when implemented in the dental practice software packages.

In this paper two new visual scoring systems are described, aimed at estimating both depth and activity of occlusal lesions. Their validity is acceptable for lesion depth estimation. However, the validity of the activity estimate is to be questioned. Both for approximal enamel and dentine lesions as for deep dentinal occlusal lesions, bite-wing radiographs are still useful for evaluation of new lesions and lesion progression. Many quantitative caries diagnostic methods are being developed, but to this date none of them has been shown to be reliably applicable in lesion monitoring. The evaluation of caries risk factors is primarily useful for selecting preventive treatment options. Other caries prediction-tests than those based on the present caries lesions are of little value. The main disadvantage of such prediction models is that they are usually limited to application in children, where caries is a disease that affects all ages.

As a result of the caries prevalence of the Dutch population the character of the routine dental examination is changing. Caries screening remains relevant for high caries risk individuals but the interpretation of early caries lesions deserves more attention, especially the assessment of progression of caries lesions in time. Diagnosis of caries by dental practitioners in the Netherlands mainly consists of visual inspection in combination with bitewing radiography and both methods play an important role in the timing of bitewing radiographs and forthcoming recall visits for oral health examination. The content and frequency of the routine dental examination are discussed in relation to the individual risk prediction as relevant aspects of quality of dental care in the Netherlands.

Objectives: To assess the opinions of general dental practitioners regarding the development and importance of clinical practice guidelines and their contribution to the quality of dental care., Methods: A questionnaire was sent to a representative sample of 1656 dentists in the Netherlands. Factor analysis was conducted to identify scales of variables, and a reliability analysis was conducted to verify the reliability of the identified scales. The effect of the independent variables is expressed as odds ratio per scale part (standard deviation, SD). Regression analyses were conducted to study determinants of the opinions on clinical guidelines., Results: The response rate was 73%; 54% of the respondents supported the development of clinical practice guidelines for dentists. Most respondents indicated that clinical practice guidelines could be used as a checklist, as a support in daily clinical decision making, and as a basis for continuing dental education. The factor analyses yielded four scale factors-contribution of guidelines to effectiveness of care (OR 1.95/SD), contribution of guidelines to professional autonomy (OR 1.70/SD), contribution of guidelines to quality of care (OR 2.52/SD), and contribution of guidelines to collaboration (OR 1.49/SD)-which complied with the criterion of Cronbach's alpha >0.60. Multiple regression analysis with the four scale factors as dependent variables yielded only extremely low correlations for practice and dentist characteristics (R(2)=0.01-0.04)., Conclusions: Only about 50% of dentists support the development and implementation of clinical guidelines. Guidelines are seen as helpful in the provision of continuing dental education and as a support in daily clinical decision making. The most important barrier to successful implementation of clinical practice guidelines is the fear of dental practitioners that guidelines will reduce their professional autonomy. Practice and dentist characteristics are unrelated to dentists' opinions on clinical practice guidelines.

Objectives: The aim of this study was to compare four methods for assessing the preferences of the dental profession for topics to be considered for the development of clinical practice guidelines., Methods: The methods were: (1) a survey among dentists, (2) an analysis of topics discussed in dental peer groups, and (3) screening of dental journals. A fourth method was obtained from method number 3. The frequencies of the reported topics were calculated for each of the methods. For the fourth method, the number of publications per topic were plotted against the year of publication, and the slope of the linear regression line was used as an indicator. Within each of the four methods, the topics were ranked according to the frequency in which they were reported, and to the slope value. The reliability of the methods was tested by the "item-rest sum correlation", which is the correlation of the rank positions of one method with the sum of the rank positions obtained by the remaining three methods., Results: In using all methods, a total of 1027 topics were obtained. Reclassification resulted in 34 topics. Moderate item-rest sum correlations ranging from 0.34 to 0.48 were found for all methods, indicating that the rank order of every method moderately predicts the sum of the rank orders obtained by all other methods. The topic 'prevention of cross-infection' had the highest overall rank position., Conclusion: It is concluded that the four applied methods appeared to provide a consistent ranking of potential topics. In view of the fact that the questionnaire method is generally applicable, this method should be preferred for assessing dentists' preferences for topics to be considered for the development of clinical practice guidelines.

Objectives: Recently, a device for detecting occlusal caries lesions based on laser fluorescence measurements (DIAGNOdent) has been introduced. The reliability (reproducibility) and validity of this laser-fluorescence device were investigated., Methods: In the in vitro part of the study, 49 permanent molars were measured by two observers using two DIAGNOdent devices. In addition, visual inspection was performed. The teeth were sectioned to measure the actual depth and area of the caries lesions. In the in vivo part of the study, 45 sites at the occlusal surfaces of permanent molar teeth in 13 patients were measured by two observers using two DIAGNOdent devices, manufactured in two successive years., Results: The reliability of both DIAGNOdent devices expressed in the intraclass correlation coefficient (ICC=0.90 for observer 1, and 0.88 for observer 2) was high, and so was the interobserver reliability (ICC=0.85 for the 1998-device, ICC=0.90 for the 1999-device). The correlation between DIAGNOdent measurements and the actual depth of the caries lesions was lower than that of visual inspection by one observer, yet higher than that of a second observer. The specificities of visual inspection (0.94 and 0.88) were higher than those of the DIAGNOdent devices, whereas the sensitivities of the DIAGNOdent devices (0.93-1.00) exceeded those of visual inspection The validity of the DIAGNOdent, expressed as the area under the receiver operating characteristic curve, was not statistically significantly different from that of visual inspection (P>0.05). The DIAGNOdent measurements showed a higher association with the enamel part of the caries lesion than with the dentinal part., Conclusions: The DIAGNOdent is suitable for monitoring small caries lesions. Because of the high reproducibility of DIAGNOdent devices produced in successive years, a DIAGNOdent device may be replaced by a new one. Due to the higher specificity, visual inspection should be preferred to diagnose occlusal caries lesions in populations with a low caries prevalence.

When enamel, dentine and substances in caries lesions are exposed to (laser) light of a specific colour, fluorescence may be induced. This principle is at the basis of two caries diagnostic methods, DIAGNOdent and Quantitative Laser (Light-induced) Fluorescence (QLF). Only the DIAGNOdent is commercially available. Bacterial porphyrins evoke fluorescence when illuminated with red light and the intensity of the emitted light is related to the size of the caries lesion. Published research indicates that the DIAGNOdent is particularly suitable for detecting small bacteria containing caries lesions, and to monitor such lesions. QLF is based on the fluorescence decrease in demineralised enamel upon exposure to blue-violet (laser) light. The intensity of the emitted light is related to the amount of mineral loss in the caries lesion. Using QLF the mineral loss in caries lesions can be measured quantitatively. Like the DIAGNOdent, QLF is particularly suitable to monitor caries lesions.

The aim of this study was to assess the effect of studying selected literature on dentists' decisions to remove asymptomatic, impacted lower third molars. A pre-test-post-test control group design was used. Given 36 patient cases, two groups of 16 general dental practitioners each were asked to assess the need for removal of asymptomatic impacted lower third molars. The cases were classified by three parameters: 'position of the third molar', 'impaction type', and 'patient age'. After studying selected literature on this subject by the intervention group, both groups were asked to assess the same cases again. Frequencies of decisions to remove the third molars were calculated. For each participant, tables were composed by crosstabulating the indication to remove a third molar with each of the three parameters. T-tests were used to test the significance of the difference between pre-test and post-test decisions. The overall number of indications to remove asymptomatic, impacted lower third molars decreased by 37% in the intervention group. In the control group, the difference between pre- and post-test was not statistically significant. It was concluded that the provision of selected literature significantly influences treatment decision making by dentists in a third molar decision task.

Recently, a device for detecting occlusal caries lesions (DIAGNOdent) has been introduced. The reproducibility and validity of this laser-fluorescence device were investigated. In the in vivo part of the study, 45 sites at the occlusal surfaces of permanent molar teeth in 13 patients were measured by 2 observers using 2 DIAGNOdent devices, one produced in 1998 and one in 1999. The interobserver reliability between both devices and both observers was established. In the in vitro part of the study, 49 permanent molars were measured by 2 observers using 2 DIAGNOdent devices. In addition, visual inspection was performed. The teeth were sectioned to measure the histological depth and area of the caries lesions. The reproducibility of both DIAGNOdent devices was high, and so was the interobserver reliability. The correlation between DIAGNOdent measurements and the actual depth of the caries lesions was lower than that of visual inspection. The correlation with the enamel part of the lesion exceeded that of the dentine part. It was concluded that the validity of the DIAGNOdent, expressed as the area under the Receiver Operating Characteristic (ROC) curve, was not statistically significantly different from that of visual inspection. Because of the high reproducibility, dental practitioners who wish to use the DIAGNOdent for monitoring caries lesions, this investigation indicates that an old device may be replaced by a new one, provided that the same tip will be used.

During cavity excavation diagnostic test are used to prevent any unnecessary removal of sound dentine. In this study the validity of a newly introduced blue dye (Quadrant CariTest) was investigated. Twenty-five carious teeth were collected immediately after extraction. The caries lesions were stepwise excavated. From four excavation steps per lesion a digital and an ordinal blue measurement was obtained. From each excavation phase a little amount of excavated dentine was cultured on blood plates. The correlation coefficients between the ordinal and the digital blue measurements and the counts of micro-organisms, expressed in log(CFU)/ml, were respectively 0.56 and 0.45. The sensitivity and the specificity of the ordinal blue measurements were 0.69 and 0.83, those of the digital blue measurements 0.76 and 0.65. The area under ROC of the ordinal blue measurements was 0.77, and that of digital blue measurements 0.70. The areas under ROC were not significantly different (p = 0.14). It was concluded that the new caries indicator is well applicable during the cavity preparation to demonstrate infected dentine.

Recently, a new film for intraoral radiography was introduced, the Kodak Insight Dental film. The manufacturer claims that this film requires a reduced exposure time compared to Ektaspeed Plus-film, whereas other relevant film characteristics remained unchanged. These claims were investigated in this study. The exposure time of the Insight-film was on average 17% less than that of Ektaspeed Plus-film upon standard manual development, and 49% less than that of Kodak Ultraspeed-film. Compared to the E-speed film, the Insight-film has an identical gradient and spatial resolution (> 10 lp/mm). Compared to the D-speed film the gradient was larger, indicating a better contrast, whereas the resolution was the same. It was concluded that the Insight Dental film can be used in intraoral radiographic diagnosis.

The decision to place sealants is a difficult one, and it has been suggested that in a low risk population it may be efficient to wait until caries is detected in the fissure. An invasive sealant technique with fissure preparation may then be indicated. The diagnostic method used in the indication of such a procedure should accurately detect both dentine caries and sound fissures: high sensitivity for dentine caries (at D3 threshold) with high specificity for enamel caries (at D1 threshold). The aims of this study were to assess the diagnostic performance of selected diagnostic methods at normal cut-offs for traditional dentine caries detection and at reduced cut-offs in relation to the desired performance mentioned above, and to assess whether fissure opening allows for accurate visual detection of dentinal caries. Data were obtained from 230 occlusal sites of 101 extracted human molar teeth. Diagnostic methods used on the entire sample were: visual inspection, electrical conductance measurements and laser fluorescence measurements. The sample was then divided into two groups. Group 1 was subjected to visual inspection after application of a dye. Group 2 was subjected to visual inspection after fissure opening only, and after subsequent dye application. Validation was performed by histological investigation. The results with cut-offs normally used in dentine caries detection were roughly in accordance with the literature, except for laser fluorescence. The sensitivity of visual inspection for dentinal caries (D3) was 17% before and 70% after fissure opening. Using reduced cut-offs, a 100% sensitivity (D3) was achieved with 2 methods, but this also resulted in 63 or 87% false positive diagnoses of sound surfaces. Visual inspection and electrical methods both showed a moderate to high sensitivity (D3) with a higher than 50% specificity (D1). It was concluded that visual inspection and electrical methods at reduced cut-offs may aid the indication of invasive sealant treatment. The visual detection of dentinal caries is substantially increased, but not perfect after fissure opening.

For both general practitioners and researchers in caries diagnostics, the true validity of available diagnostic techniques is of considerable interest. Yet, for both bitewing radiography and fiber-optic transillumination, this is still not accurately known, nor is it clear which of the two techniques performs best clinically. This study's purpose was to estimate the clinical performance of the two techniques in diagnosing approximal caries lesions in low-caries-prevalence populations. Clinical studies that compare the two techniques were selected from literature. We determined 2 x 2 contingency tables from these studies and calculated one overall contingency table. The cut-off for decay was at dentinal caries. Assuming that erroneous outcomes from both techniques are mutually independent, we expressed diagnostic sensitivity and specificity of the two techniques as functions of the contingency table cell contents, with caries prevalence as the parameter. Because the caries prevalence was unknown, every sensitivity and specificity value was possible. From the conditions that sensitivity, specificity, and caries prevalence are always between one and zero, a limited range of sensitivity and specificity values was obtained. Three situations were examined: Bitewing radiography specificity is 1, fiber-optic transillumination specificity is 1, and both specificities are equal. Under these conditions, the bitewing radiography sensitivity was between 1.00 and 0.71 +/- 0.01, and the fiber-optic transillumination sensitivity was between 0.70 +/- 0.01 and 0.50 +/- 0.02. Both specificities were between 1.00 and 0.99. We concluded that the two techniques have comparable specificities. but that the fiber-optic transillumination sensitivity is significantly lower than that for bitewing radiography.

Recently erupted teeth are more sensitive to dental caries than teeth that have remained free from caries lesions for a few years after eruption. It has been hypothesized that this may be ascribed to differences in enamel porosity. The objective of the present work was to assess the time-dependence of electrical conductance, as an indication of porosity, of occlusal enamel in recently erupted permanent molar teeth. Fifty children aged 5-15 years of age, receiving regular dental care at six-month intervals, participated in the study when their first molar teeth (in 5- to 6-year-olds) or their second molar teeth (in 11- to 15-year-olds) had not been exposed to the oral environment for more than six months. On the first semi-annual check-up after eruption of a first or second molar, baseline diagnostic measurements, i.e., visual inspection and electrical conductance measurements (ECMs), were made at three or four pre-defined sites in the fissures. Subsequently, data collection was repeated every six months for three years. Sites were excluded from ECMs when a caries lesion was observed at a site by visual inspection. After 36 months, there were 257 sites in teeth considered sound upon visual examination. The ECM values of these sound sites showed a clear decrease with time after the first examination. The conductance decreased on average from 0.13 (Momega)(-1) to 0.059 (Momega)(-1). Since the conductance is assumed to be proportional to the porosity of the enamel, the latter decreased by a factor of 2.2 over the 36-month period. The results furthermore indicated a higher conductance for maxillary than for mandibular enamel. Almost all sites in that sample appeared to be in teeth that were observed for the first time during the months September to December. Electrical conductance, and therefore enamel porosity, of the sites showed a periodic variation with season of observation: In the fall, the conductance was higher than in the spring. This implies that a dentist should be more prudent in the fall than in the spring when indicating restorative treatment of an incipient caries lesion.

Aim: The aim of this study was to investigate the influence of a low intensity alternating current on the odontoblasts and odontoblast layer and compare this with the effects of a direct current., Methodology: Teeth extracted for orthodontic reasons were immersed in physiological saline stabilized with thymol crystals. Within 1 h of extraction, an alternating or direct current was applied on the crown in the direction of the apex of the tooth for 120-360 s. The current doses were 12, 30, 60, 600, 1800, 3600, 7200, 24,000 and 144,000 microC. The teeth were fixed in Bouin or Baker fluids, the pulps removed, dehydrated and immersed in paraffin, then sectioned, stained with haematoxylin and eosin, and studied under a light microscope., Results: Neither direct nor alternating current, similar to that applied in electrical caries diagnosis caused histological changes in the odontoblasts., Conclusions: There was no difference between direct and low intensity alternating current in the response of the odontoblast.

Aim of the study was to evaluate a method for selecting topics suitable for developing dental clinical practice guidelines in the Netherlands, based on an analysis of Dutch dental journals. A search for dental clinical topics was conducted by analysing Dutch dental journals, magazines and series over the period 1992-1997. The numbers of publications per topic were plotted against the publication years. The number of publications as well as the value of the slope of the linear regression were considered to be indicators of the importance of a topic. 'Dental implants (indication)' had the highest number of publications, followed by 'orthodontic treatment planning' and 'periodontology (indication)'. The topic 'practice hygiene' showed the highest value of the slope of the linear regression, followed by 'TMJ dysfunction' and 'dental implants (indication)'. With this method, it is feasible to detect changes and tendencies in the Dutch dental literature. It permits a selection of clinically relevant topics over a time span. It was concluded that this method may be very useful in the selection of a topic, but should probably be combined with other methods.

Introduction: Problems that may arise in resin composite Class 2 restorations include microleakage and postoperative sensitivity. However, limited in-vivo research is conducted to evaluate these processes., Aim: The aim of this study was to assess postoperative sensitivity, microleakage and the pooling of adhesives in relation to Class 2 box-type composite restorations placed in vivo using various adhesive systems and application techniques., Materials and Methods: One hundred and forty-four Class 2 box restorations were placed in the mesial and distal surfaces of 72 premolar teeth in-vivo using one of three combinations of adhesive systems and three filling techniques. After 6 weeks of clinical service postoperative sensitivity was recorded. The teeth were then extracted, immersed in a dye solution and sectioned. Microleakage and pooling of the adhesive was recorded. Statistical analysis involved logistic regression and chi2 tests to identify differences between groups at p < 0.05., Results: Of the 144 restorations, 65 showed minimal cervical leakage in enamel, 5 suffered leakage into dentin and 74 were free of microleakage. No statistically significant differences were found in cervical microleakage between the adhesive systems or between filling procedures. Occlusal microleakage in the enamel was present in 16 of the 160 restorations. Liner Bond 2 restorations leaked significantly more at the occlusal surface (p < 0.05). Pooling of the adhesive was significantly less when PhotoBond was used. No spontaneous postoperative sensitivity was reported. Twenty-eight restorations were sensitive to loading. Postoperative sensitivity was significantly less in patients with Liner Bond 2 restorations., Conclusions: The adhesive systems used in this study showed minimal leakage into dentin in vivo. Using Liner Bond 2, restorations exhibited more occlusal leakage but were significantly less sensitive to loading.

Objectives: Attempts have been made to develop diagnostic methods which enable an early diagnosis of occlusal lesions which are not detectable by visual inspection. The aim of this study was to compare the performance of visual inspection focused on finding signs of fissure decalcification and discoloration, visual inspection upon fibre-optic transillumination (FOTI), and electrical conductance measurements (ECMs) in predicting the onset of occlusal caries in 6- and 11-year-old children., Methods: Fifty children aged 5-7 and 11-15 years, having first or second permanent molar teeth that were not exposed to the oral environment for more than half a year, participated in the study. Following baseline data recording, the diagnostic measurements were repeated six times at 6-month intervals over a period of 2.5 years., Results: Data were collected at predefined sites in the fissures. During the study, 220 of the 652 sites, i.e. 75 of 197 molars in 31 of the 50 children were judged to require a sealant or a sealant restoration. Two examiners jointly decided on the decay status at the sites. Survival plots showed that ECMs were superior to FOTI and fissure discoloration in predicting the onset of occlusal caries, although the differences were small., Conclusion: ECM is a better predictor of occlusal caries than fissure discoloration and FOTI, although the differences among the performance of the three methods in this study were very small. A cost-effective analysis is envisaged to obtain insight into the practical value of ECMs in the prediction of occlusal caries and, thus, into the effectiveness of sealant application.

Objectives: The aim of this study was to assess the effect of a chlorhexidine varnish on occlusal caries incidence when applied 6-monthly into the fissures of erupting and freshly erupted permanent molars., Methods: In a double-blind clinical trial, 332 children aged 5/6 and 11/12 years attending a Child Dental Health Centre were randomly assigned to a control and an experimental group. Criteria for inclusion in the study were that all first permanent molars in 5-6-year-olds and all second permanent molars in 11-12-year-olds either had recently erupted, or were in a stage of eruption, or would erupt within half a year. At baseline, counts of dmfs/DMFS and mutans streptococci in saliva were recorded. During a maximum of 3 years, every 6 months the occlusal surfaces of molars in the experimental group received a 40% chlorhexidine varnish application, whereas those in the control group received a placebo varnish application., Results: Data of 316 children were analysed and ANOVA showed no significant occlusal caries reduction in this sample of Dutch 5/6- and 11/12-year-old children. After stratification into low and high caries risk groups, a statistically significant caries-reducing effect on occlusal caries in permanent molars was found in the group of children with > or = 10(6) mutans streptococci per ml saliva (P < 0.05)., Conclusion: Six-monthly application of chlorhexidine varnish has no caries-reducing effect on occlusal caries in recently erupted permanent molars in a population with low caries prevalence.

Objective: In this study an attempt was made to explain some of the interobserver variation in re-restoration decision making using., Method: A simplified re-restoration case was shown to 22 dentists who were asked what treatment decision they would make, and what factors would play a role in their decision. The treatment decisions were compared to the outcomes of a knowledge-system on re-restoration decision making., Results: The dentists unanimously selected re-restoration as the treatment alternative. Half of the dentists preferred amalgam, and the other half chose composite as restorative material. This variation could be explained almost fully by the dentists' weighs on the factors 'tissue loss during preparation', 'restoration and preservation of the chewing function' and 'prognosis and durability of the restoration'. The knowledge system indicated that more than 80% of the dentists actually should have selected composite resin for a restorative material., Conclusions: It was concluded that the availability of knowledge and its application can explain variation in re-restoration decisions. Knowledge systems can be used in designing practice guidelines.

Objective: To estimate the role of computer-CPED in the Netherlands to the year 2008., Design: Computer-assisted learning is currently employed in many modern undergraduate dental curricula. It could also play an important role in providing continuing professional education in dentistry (CPED) to general dental practitioners. Computer-CPED offers teacher-independent and individualized interaction by distance learning., Methods: A simulation study was conducted. Entry data were either derived from publications or were estimated., Results: The results indicate that the demand for CPED will exceed the supply by 2002., Conclusion: The introduction of Computer CPED may substantially contribute to the supply of CPED-courses in de first decade of the next century. By 2008 about 25% of the CPED-courses could be provided by computer education.

Electrical conductance measurements are being used experimentally for occlusal caries detection. Recently, it was suggested to cover the fissure system with a conducting medium, resulting in a surface-specific measurement. It was the aim of this study to determine in vitro the reproducibility of this modified technique for occlusal caries in posterior teeth, to determine for a large study sample the correlation between the electrical measurements and histological lesion depth, and to evaluate the difference between results for premolars and molars. For the reproducibility determination, surface-specific electrical resistance measurements were made using a sample of 68 posterior teeth. Eight operators performed measurements on all teeth, and repeated measurements on 24 teeth. The validity study included the previous sample and the collected samples from two more studies, resulting in a total sample of 325 posterior teeth. One operator had performed electrical resistance measurements on all teeth in the sample. Reproducibility was good: mean Pearson's correlation coefficient 0.89 (+/-0.05) for interexaminer correlation, and 0.86 (+/-0.12) for intra-examiner correlation, using log (resistance) as the result parameter. The correlation coefficient between log(resistance) and histological lesion depth for the large sample was -0.78 for all teeth, -0.64 for premolars, and -0.73 for molars. The regression line for molars was located below the regression line for premolars: at a hypothetical histology score of 2.5 (a dentine caries threshold) the estimated resistance threshold would be 507 kOmega for premolars, and 233 kOmega for molars. Converted to Electronic Caries Monitor (ECM) readings, the difference is about 1.4 on the ECM scale. It was concluded that the in vitro reproducibility of the described surface-specific method for electrical resistance measurement is very good, even for inexperienced operators. The correlation between measurements and histological lesion depth is moderate to good. The method is sensitive to electrode area differences, which will result in different clinical cut-offs for caries diagnosis in premolar and molar teeth.

Objectives: The purpose of this study was to compare microleakage, gap formation, thickness of the adhesive layer and its radiographic appearance associated with four adhesive restorative procedures for class I cavities., Methods: Adhesive systems with easy handling characteristics were selected for the restoration of class I cavities in extracted third molars. Bitewing radiographs were taken of each tooth and four observers were asked to assess the presence of the adhesive layer. Microleakage, gap width and the thickness of the adhesive layer of each restoration were measured upon sectioning of the teeth., Results: Microleakage in the experimental restorations was minimal. The thickness of the adhesive layers and gap formation varied among different adhesive systems. The adhesive system with self-etching primer produced the highest percentage gap-free restorations. Thick adhesive layers could be detected on the radiograph. ROC analysis of the results validates the diagnosis from the radiograph., Conclusions: The four restorative systems performed well in the prevention of microleakage. The use of a resin modified glass-ionomer cement base did not prevent gap formation compared with the all-etch bonding systems used in this study. The presence of an adhesive layer contributed to the prevention of gap formation, independently of the bonding system used. Thick adhesive layers could be detected on the radiograph.

New technology may create additional opportunities for learning in dental education. One of these new features is a multimedia approach, courseware combining sound, text, stills and video with interactive learning. A multimedia program was developed to train dental students and dental practitioners in decision making and problem solving in endodontics. This study compared the effects of the multimedia program with a more traditional approach consisting of written information, without interaction. 28, 4th-year dental students at the University of Kentucky in Lexington, KY, USA were randomly assigned to the multimedia or the text-based groups. They were given a written pre-test using 2 cases of dental pain and were instructed to study independently using either the multimedia program (group A) or the written information (group B). No restrictions were imposed on the amount of time to be invested, and the total study time was recorded for each student. 3 weeks after the pre-test, the students completed the post-test. A total of 18 students completed both the pre-test and the post-test and their scores were included in the final data. Statistical analysis of the average scores using paired t-tests revealed no significant difference between the performance of the students in either group, indicating that the multimedia approach to learning endodontic problem solving may successfully replace traditional learning strategies.

The instruments clinically available for the diagnosis of approximal caries lesions are inadequate to detect lesions early and quantitatively. The aim of this study was to investigate whether wavelength-dependent light scattering and absorption of carious tissues may be utilized for the quantitative diagnosis of these small approximal caries lesions. Seventeen extracted premolar teeth were transilluminated at an approximal surface with a glass fiber, which transported the light from a halogen light bulb. Seven approximal surfaces contained a naturally developed small white-spot lesion, and 5 surfaces a small discolored lesion. Five teeth were sound. The occlusal surface was imaged with a CCD camera. Light in the blue and red portions of the electromagnetic spectrum was selected by means of Schott glass filters. From the obtained images, average effective decadic optical thickness differences were determined. These were plotted as a function of average mineral loss assessed by means of wavelength-independent microradiography. The correlation coefficient between the average effective decadic optical thickness difference and average mineral loss was r = 0.79 (95% CI: 0.47 ... 0.93). Different sources of variation that influence the observed correlation were defined and quantified. From these measurements, the correlation coefficient between average effective decadic optical thickness difference and "true' average mineral loss was estimated to be r = 0.92 (95% CI: 0.77 ... 0.97). The results indicate that early and, in principle, also quantitative diagnosis of approximal caries lesions is feasible when wavelength-dependent light propagation through carious tissues is utilized.

Practice guidelines provide opportunities for monitoring and improving dental health care. A survey was conducted among 78 departments at dental societies, scientific dental associations and health care insurance companies in the Netherlands to obtain insight into the number and quality of practice guidelines available. The response rate was 67%. Written materials were analysed and 21 practice guidelines were identified as such. The results of the analysis indicate that many initiatives to construct and implement practice guidelines have been taken. However, these initiatives were insufficiently coordinated and existing guidelines may be subject to improvement. Main improvement would be to demonstrate the validity and reliability of the existing guidelines and, more in general, to provide a sound scientific basis to the development and implementation of practice guidelines.

The mere detection of caries lesions is insufficient for optimal treatment decision-making. Hence, the aim of this study was to investigate whether quantitative information about approximal lesion depth can be obtained from a technique based on the wavelength dependency of light propagation and additional use of a dye. Another aim was to compare the diagnostic performance of the optical technique and bitewing radiography. Measurements were performed on 33 extracted premolar teeth. Twelve proximal surfaces had white-spot, and 17 had discoloured small lesions. Four surfaces were sound. The teeth were transilluminated with a single glass fibre at the approximal surface before and after dye application. The occlusal surface was imaged with a CCD camera. Light in the blue and red part of the electromagnetic spectrum was selected using Schott glass filters. Average decadic optical thickness differences, delta bl-rd tau eff, were estimated and plotted as a function of normalised lesion depth, dhist, established from histological validation by two observers. The Spearman rank correlation was rs (delta bl-rd tau eff, dhist) = 0.87 (95% confidence interval, CI: 0.74-0.94). A marked increase in average decadic optical thickness in the blue part of the electromagnetic spectrum, delta dye tau eff, was observed for those lesion that, upon direct visual inspection of the approximal surface, clearly showed dye uptake. Bitewing radiographic depth ratings of two observers were plotted as a function of dhist. The correlations were rs (dRA,1, dhist) = 0.62 (95% CI: 0.34-0.80), rs (dRA,2, dhist) = 0.75 (95% CI: 0.54-0.87), and between the observers rs (dRA,1, dRA,2) = 0.44 (95% CI: 0.10-0.69). The p values of rs (delta bl-rd tau eff, dhist) -rs (dRA1,1, dhist) and rs (delta bl-rd tau eff, dhist) -rs (dRA,2, dhist) were p1 = 0.01 and p2 = 0.08, respectively. It was concluded that quantitative information about lesion depth can be obtained optically. The dye penetrates into only a limited number of caries lesions, in which cases dye uptake is detectable in transillumination geometry. Under laboratory circumstances the optical technique performs as well as bitewing radiography in the diagnosis of small approximal caries lesions.

Bitewing radiographs should be taken on an individual indication. The individual's caries risk is an important factor in determining the frequency of bitewing radiographs and, therefore, a dentist should estimate the individual's caries risk. Given two serial bitewing radiographs, the dentist should be able to distinguish freshly developed caries lesions, which require preventive or restorative treatment, from old remineralized lesions, which do not require any treatment at all. Assessment of caries progression from serial bitewing radiographs should also provide the dentist with information to determine the moment of subsequent bitewing radiographs. Because in many western countries the caries prevalence is quite low, this is a complicated task, since the dentist is expected to carry out the diagnostic and decision making process without errors. The true probability of caries progression was derived and plotted as a function of the time span between two bitewing radiographs. The results indicated that the interval between standardized serial bitewing radiographs should be approximately three years for individuals which run a high risk of developing caries, and four years for individuals with a low caries risk.

Monitoring and improving the quality of rendered health care in a systematic way has been laid down in Dutch legislation. In Dutch family health care particularly, many initiatives have already been taken to improve the quality of health care utilizing a pre-defined systematic approach. In recent years various groups in The Netherlands took initiatives to maintain and improve quality of care in dentistry. This publication reports on some of the frequently used constructs and the state of the art in The Netherlands. A proposition for the development of a system of quality monitoring and improvement is presented. It is furthermore suggested that all parties involved should collaborate to achieve the joint goal.

The methods currently utilized in dentistry to detect caries lesions have their limitations and alternatives are being investigated. A promising option is tooth transillumination which is based on an increase of light scattering or light absorption in the affected tissue region. In this study transillumination applied to detect approximal caries lesions was investigated using premolar teeth containing simulated caries lesions. Cavities were drilled at the approximal surface and filled with light absorbing and light scattering fluids in different dye and particle concentrations to model successive stages of lesion progress. For light absorbing cavities the extinction as function of the decadic absorption coefficient measured at the occlusal surface could be approximated by the Lambert-Beer law (r = 0.98 +/- 0.01). For light scattering cavities the extinction as a function of the decadic reduced scatter coefficient wad fitted to a straight line (r = 0.98 +/- 0.03) for mu's (lambda = 633 nm) < 1.25 mm-1. For higher reduced decadic scatter coefficients the curves levelled off due to multiple scattering. In addition, the contribution of the dentinal cavity part to the radiance change induced by the total cavity was estimated. For light absorbing cavities illuminated with red light the average contribution was 10.5 (SD 4.2)% and for those illuminated with green light it was 1.4 (SD 0.9)%, indicating that the radiance change caused by a caries lesion is mainly determined by the enamel lesion part.

The use of sealants and sealant restorations has increased considerably over the past 10 years, and with it increased the problem of detecting secondary caries and marginal (micro)leakage. It was the purpose of this study to investigate the validity of electrical conductance measurements (ECMs) in diagnosing marginal leakage into dentine of sealants and sealant restorations. Ninety extracted premolar teeth were divided into three groups. Initial ECMs, denoted 'baseline ECMs', were conducted in all three groups by placing the probe tip of an Electronic Caries Monitor in the occlusal fissure which was filled with a dentifrice. The ECMs were divided by the area, yielding ECM/mm2 values. In group A 30 teeth were treated to receive 'nonleaking sealants'. In the 30 teeth of group B a narrow groove was cut at the occlusal surface reaching the dentine and restored by the application of a sealant without etching of the adjacent enamel to create a high probability of marginal leakage. The samples in group C received the same treatment as those in group B, but in this group the enamel was etched to reduce the probability of marginal leakage. The ECMs subsequently conducted were denoted 'sealed/restored ECMs'. Teeth in groups B and C were thermocycled 700 times (4-67 degrees C) to provoke leakage, after which ECMs were conducted (denoted 'ECMs after thermocycling'). The teeth were immersed in fuchsin for 24 h and cut along the fissure system to validate marginal leakage. The electrical conductance decreased significantly from baseline to the sealed/restored stage in all groups (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Electrical conductance measurements are being used experimentally to diagnose caries. Current equipment, e.g. the electronic caries monitor (ECM), uses a probe to scan occlusal fissures. For full-mouth examination this method is rather time-consuming. A method with which only one measurement is needed for an entire (occlusal) surface would be preferable. However, the enlargement of the area being measured will influence the conductance. It was the purpose of this study to investigate the relationship between the electrical conductance of human teeth and the enamel electrode area, and to compare the range of results of surface measurements with those of the scanning method. Twenty-five sound extracted teeth were selected for the study. The reference electrode of the ECM was connected to the roots. The buccal surface was blotted dry, and a coloured dentifrice was syringed in increments onto the surface. After each increment the surface was photographed together with a metric reference, a conductance measurement was performed by holding the ECM probe tip in the dentifrice, and the ECM reading was recorded. For each tooth between 5 and 10 increments were applied and measured. The photographs were digitised and the electrode areas were calculated. A least squares curve fitting procedure yielded a linear relationship between conductance and electrode area (0.88 < or = R2 < or = 1.0, mean R2 = 0.97). For most teeth the threshold for dentinal caries as used for scanning ECM measurements (ECM reading = 6.00) was reached only when the electrode area exceeded 12 mm2. For 6 teeth this conductance was already reached between 5 and 12 mm2.(ABSTRACT TRUNCATED AT 250 WORDS)

Techniques based on transillumination of teeth with visible light will be a valuable aid in caries diagnosis, if a higher sensitivity than that of the present Foti method is achieved. Therefore, a better understanding of light propagation through teeth is required, and hence it is useful to investigate the propagation of light through sound dental material. In this study the intensities emanating from the surfaces of enamel and dentine bars were measured when these bars were illuminated using a fibre rod transporting the light from a HeNe laser (lambda = 633 nm) as a light source. From the measured intensities, the radiant fluxes emanating from the surfaces were calculated. To account for a directional dependence of these fluxes, optical anisotropy in dental material was investigated by comparing the transmitted light intensity in a direction perpendicular and parallel to the approximal surface of the tooth from which the sample was cut. The mean ratio of the transmitted intensities in perpendicular and parallel direction was 0.86 +/- 0.06 for enamel and 2.88 +/- 0.43 for dentine. In addition, for enamel the asymmetry parameter, g, was estimated. The averaged value was g = 0.68 +/- 0.09. It was concluded that for dentine the optical anisotropy as measured supports the idea that tubules are the predominant cause of scattering in dentine. For enamel the results indicate that the hydroxyapatite crystals contribute significantly to scattering and that the influence of the prism structure on the light propagation is small.

Pit-and-fissure caries lesions contribute greatly to the caries incidence in permanent molar teeth in children. To date, the diagnosis of occlusal caries is still performed mainly by visual inspection, periodically aided by bite-wing radiography. However, in detecting small occlusal carious lesions, these methods perform inadequately, especially in low caries prevalence populations or individuals. The use of electrical conductance measurements (ECMs) has been evaluated to improve the diagnosis of small occlusal carious lesions. The aim of this study was to monitor the electrical conductance of fissure enamel in recently erupted molar teeth and to relate these measurements to the caries status. 50 children aged 5-15 years, having first or second permanent molars that were not exposed to the oral environment for more than 6 months, participated in the study. The diagnostic systems evaluated were visual inspection and ECMs. Following baseline data recording, diagnostic measurements were repeated three times within 18 months. Data were collected at predefined sites in the fissures. 18 months after baseline recording, 179 sites at 60 molar teeth in 27 children were judged to require a sealant based on visual inspection. After removal of carious tissue, two examiners jointly decided on the status of decay as per the criteria: 0 = no caries or caries limited to enamel, and 1 = caries involving dentine. The sensitivity of ECM continued to increase with time after a slight initial dip, whereas the specificity continuously increased after baseline measurements as a result of the decreasing amount of false-positive diagnoses.(ABSTRACT TRUNCATED AT 250 WORDS)