Sofia Tranæus

Validation of DIAGNOdent for quantification of smooth-surface caries: an in vitro study

The aims were 1) to validate a laser-based device, KaVo DIAGNOdent, for quantification of caries lesions on smooth surfaces, using histopathologic and microradiographic analyses as the gold standard, and 2) to test inter- and intra-observer agreements. We also investigated the influence on DIAGNOdent readings of the storage medium used for extracted teeth. Two observers measured independently the tooth surfaces of 40 extracted premolars that had been stored in thymol-saturated saline. After subsequent storage in neutral-buffered formalin for 14 days they were re-measured. The teeth were then sectioned for histopathologic and microradiographic analysis. The Spearman rank correlation coefficients between lesion depth and DIAGNOdent readings were 0.78–0.83 and 0.85 for teeth stored in thymol-saturated saline and formalin, respectively. Inter- and intra-observer agreements were 0.94 and 0.95 when the teeth were stored in thymol-saturated saline. The DIAGNOdent reading was almost 1.5 times higher for teeth stored in formalin than for those stored in thymol saline. The Spearman rank correlation coefficient between mineral loss in enamel (ΔZ) and DIAGNOdent readings ranged from 0.64 to 0.68. It was concluded that DIAGNOdent may be helpful for assessing smooth-surface caries, but the cut-off points need to be assessed under clinical conditions. The increase in fluorescence associated with storage of teeth in formalin warrants further investigation.

Caries risk assessment. A systematic review

Abstract Objective. To assess the ability of multivariate models and single factors to correctly identify future caries development in pre-school children and schoolchildren/adolescents. Study design. A systematic literature search for relevant papers was conducted with pre-determined inclusion criteria. Abstracts and full-text articles were assessed independently by two reviewers. The quality of studies was graded according to the QUADAS tool. The quality of evidence of models and single predictors was assessed using the GRADE approach. Results. Ninety original articles fulfilled the inclusion criteria. Seven studies had high quality, 35 moderate and the rest poor quality. The accuracy of multivariate models was higher for pre-school children than for schoolchildren/adolescents. However, the models had seldom been validated in independent populations, making their accuracy uncertain. Of the single predictors, baseline caries experience had moderate/good accuracy in pre-school children and limited accuracy in schoolchildren/adolescents. The period of highest risk for caries incidence in permanent teeth was the first few years after tooth eruption. In general, the quality of evidence was limited. Conclusions. Multivariate models and baseline caries prevalence performed better in pre-school children than in schoolchildren/adolescents. Baseline caries prevalence was the most accurate single predictor in all age groups. The heterogeneity of populations, models, outcome criteria, measures and reporting hampered the synthesis of results. There is a great need to standardize study design, outcome measures and reporting of data in studies on caries risk assessment. The accuracy of prediction models should be validated in at least one independent population.

Diagnosis of the condition of the dental pulp: a systematic review.

The aim of this systematic review was to appraise the diagnostic accuracy of signs/symptoms and tests used to determine the condition of the pulp in teeth affected by deep caries, trauma or other types of injury. Radiographic methods were not included. The electronic literature search included the databases PubMed, EMBASE, The Cochrane Central Register of Controlled Trials and Cochrane Reviews from January 1950 to June 2011. The complete search strategy is given in an Appendix S1 (available online as Supporting Information). In addition, hand searches were made. Two reviewers independently assessed abstracts and full-text articles. An article was read in full text if at least one of the two reviewers considered an abstract to be potentially relevant. Altogether, 155 articles were read in full text. Of these, 18 studies fulfilled pre-specified inclusion criteria. The quality of included articles was assessed using the QUADAS tool. Based on studies of high or moderate quality, the quality of evidence of each diagnostic method/test was rated in four levels according to GRADE. No study reached high quality; two were of moderate quality. The overall evidence was insufficient to assess the value of toothache or abnormal reaction to heat/cold stimulation for determining the pulp condition. The same applies to methods for establishing pulp status, including electric or thermal pulp testing, or methods for measuring pulpal blood circulation. In general, there are major shortcomings in the design, conduct and reporting of studies in this domain of dental research.

In vivo Repeatability and Reproducibility of the Quantitative Light-Induced Fluorescence Method

In vivo repeatability and reproducibility of the quantitative light-induced fluorescence (QLF) method were tested with respect to three variables: lesion area, and average and maximum changes in lesion fluorescence. To test the image-capturing stages, three analysts each captured images of 15 incipient smooth surface lesions in vivo, and the images were analysed by one of the analysts. To test the analytical stage of the method, three analysts analysed the images of 15 in vivo incipient smooth surface lesions. For the image-capturing stage, inter-examiner reliability showed an intra-class correlation coefficient (r) between 0.95 and 0.98. For the analytical stage, intra-examiner reliability for all three analysts showed a value of r between 0.93 and 0.99. Inter-examiner reliability showed a value of r between 0.95 and 0.99. It was concluded that the in vivo repeatability and reproducibility of the QLF method are excellent.

Longevity of posterior resin composite restorations in adults - A systematic review

OBJECTIVE To conduct a systematic review of the literature on the longevity of posterior resin composite restorations in adults. MATERIAL AND METHODS A systematic literature search was conducted according to pre-determined criteria for inclusion and exclusion. The studies selected were prospective clinical trials with a minimum follow-up time of 4 years, 40 restorations per experimental group and an annual attrition rate of less than 5%. Initially, abstracts and full-text articles were assessed independently and the assessment was subsequently agreed on by five reviewers. The methodological quality of the studies was assessed according to the Swedish Council on Health Technology Assessment (SBU) standard checklist for determining the extent to which studies meet basic quality criteria. RESULTS In all, the literature search identified 4275 abstracts and 93 articles were read in full-text. There were eighteen studies which met the criteria for inclusion, eight of which were included in the analysis. There were 80 failures of restorations with a total follow-up time at risk for failure of 62,030 months. The overall incidence rate for all causes of failure was 1.55 lost restorations per 100 restoration years. The most common biological reason for failure (a total of 31 restorations) was secondary caries, with or without fracture of the restoration. The quality of the evidence was low. CONCLUSIONS In an efficacy setting, the overall survival proportion of posterior resin composite restorations is high. The major reasons for failure are secondary caries and restoration fracture which supports the importance of adequate follow-up time. CLINICAL SIGNIFICANCE The overall survival proportion of posterior composite restorations was high, but the results cannot be extrapolated to an effectiveness setting. The importance of adequate follow-up time is supported by the finding that secondary caries often occurred after 3 years or later.

In vitro quantification of white spot enamel lesions adjacent to fixed orthodontic appliances using quantitative light‐induced fluorescence and DIAGNOdent

The aims of this in vitro study were 2‐fold: 1) to evaluate two fluorescence methods (DIAGNOdent and QLF (quantitative light‐induced fluorescence)) for quantification of white spot lesions adjacent to fixed orthodontic appliances; and 2) to determine the inter‐observer agreement of the DIAGNOdent and QLF methods for quantification of incipient enamel lesions adjacent to fixed orthodontic appliances. Forty‐one premolar teeth with visually sound smooth surfaces or visually white spot enamel lesions were included in the study. Orthodontic brackets were fixed adjacent to the lesions, thus simulating the position of fixed appliances during orthodontic treatment. All teeth were measured using both the DIAGNOdent and QLF methods. Of the 41 teeth, 20 smooth surfaces were randomly selected and analyzed by 4 operators using both DIAGNOdent and QLF. The teeth were sectioned into 300‐μm‐thick slices using a water‐cooled diamond saw and the slices manually ground to 80–100 μm thickness. Histopathology and transverse microradiography were performed to provide the gold standards for verification of lesion depth and mineral loss, respectively. The Spearman rank correlation coefficients between lesion depth determined by histopathology and the DIAGNOdent and QLF were 0.76 and 0.82, respectively, whereas the Pearson correlation coefficients between mineral loss and the two methods were 0.64 and 0.84, respectively. Inter‐observer agreement was found to be 0.80 and 0.93 for DIAGNOdent and QLF, respectively. In conclusion, QLF may be a suitable method for quantifying incipient carious lesions adjacent to fixed orthodontic appliances.

Consistency of DIAGNOdent instruments for clinical assessment of fissure caries.

DIAGNOdent (KaVo, Biberach, Germany) has shown high diagnostic accuracy and intra‐operator agreement for caries detection, both in vitro and in vivo. The aims of this study were to compare DIAGNOdent with visual examination (VI) and bitewing radiographs (BW) for clinical assessment of occlusal fissures, and to evaluate inter‐device consistency of clinical recording using four different DIAGNOdent instruments; secondly, to correlate DIAGNOdent readings with microbial culture of the measured site. The subjects were young adults, the material comprising 34 occlusal fissures, scheduled for restorative treatment at the Dental School Clinic of the University of Iceland. Two examiners conducted visual and radiographic assessments. One examiner measured each site with four DIAGNOdent instruments in random order. The fissure was then opened and lesion depth was classified on a 4‐point scale. Bacterial samples were taken from the fissure before and after opening. Intra‐operator agreement was high (r = 0.85–0.98). Inter‐device correlation for the four DIAGNOdent instruments was significant in all cases (r = 0.81–0.92). However, a common cut‐off point could not be determined. There was weak but significant correlation between DIAGNOdent readings and all three classes of lesion depth. Level of infection showed very weak correlation with the DIAGNOdent readings. It was concluded that DIAGNOdent is more reliable in detecting dentinal caries if a proper cut‐off point is used than in indicating actual lesion depth. Readings from the different instruments were not directly comparable, however, owing to the lack of a common cut‐off point.

Adjunct methods for caries detection: A systematic review of literature

Abstract Objective. To assess the diagnostic accuracy of adjunct methods used to detect and quantify dental caries. Study design. A systematic literature search for relevant papers was conducted with pre-determined inclusion and exclusion criteria. Abstracts and full text articles were assessed independently by two reviewers. The study characteristics were compiled in tables and quality graded according to the QUADAS tool. The level of evidence for each diagnostic technology (fiber-optic methods, fluorescence methods, electrical methods) was based on studies of high or moderate quality according to the GRADE approach. Results. Twenty-five reports fulfilled the inclusion criteria. One study was of high quality, 10 were graded as moderate, while the remaining 14 reports were of low quality. Electrical methods (ECM) and laser fluorescence (DIAGNOdent) displayed sensitivities and specificities around 70–80% regarding occlusal dentin lesions with a mean Youdens index of 0.52–0.54. The mean accuracy of laser fluorescence for detecting enamel and dentin lesions was 0.68 and 0.91, respectively. The heterogeneity of the published reports hampered the analysis. Conclusions. There was insufficient scientific evidence for diagnostic accuracy regarding fiber-optic methods and quantitative light-induced fluorescence (+OOO). The electrical methods and laser fluorescence could be useful adjuncts to visual-tactile and radiographic examinations, especially on occlusal surfaces in permanent and primary molars, but evidence was graded as limited (++OO). No conclusions could be drawn regarding the cost-effectiveness of the methods. There is an obvious need to standardize study designs for in vitro and in vivo validation of the different methods.

In vivo detection of non-cavitated caries lesions on occlusal surfaces by visual inspection and quantitative light-induced fluorescence.

Objective. The aim of this clinical caries detection study was to compare the outcome of quantitative light-induced fluorescence (QLF) and meticulous visual inspection (VI) in detecting non-cavitated caries lesions on occlusal surfaces in young adolescents. It was hypothesized that the respective diagnostic performances of meticulous VI and QLF are similar. Material and methods. The subjects were 34 fifteen-year-old students. Five-hundred-and-seventeen cleaned occlusal surfaces were air-dried and examined using VI. Fluorescence images were captured with QLF equipment and custom software was used to display, store and analyze the images. The area of the lesion (area; mm2), fluorescence loss (ΔF;%) and ΔQ (Area*ΔF; mm2*%) were determined at a QLF threshold of −5%. The presence/absence of non-cavitated lesions was independently recorded with both methods. Results. 78.8% of all untreated surfaces were classified as sound or as having a non-cavitated lesion with both methods uniformly (VI+QLF). On 7.1% of all surfaces a lesion was detected by VI only and on 14.1% by QLF only. All parameters (Area, ΔF, ΔQ) differed significantly between lesions registered with both methods (VI+QLF) and lesions recorded with QLF only. Conclusions. It was concluded that our hypothesis cannot be confirmed. The study shows that QLF detects (1) more non-cavitated occlusal lesions and (2) smaller lesions compared to VI. However, taking into consideration time-consuming image capturing and analysis, QLF is not really practical for use in the dental office.

A New in vivo Method for Measuring Caries Activity Using Quantitative Light-Induced Fluorescence

The aim of this in vivo study was to assess the association between caries prevalence and activity parameters and the properties of etched sites measured with quantitative light-induced fluorescence (QLF). In a clinical method, two areas of a deciduous tooth were etched in each of 44 children (mean age 8.23 years ± 1.45) with 36% phosphoric acid gel for 1 min and 4 min, respectively. ΔQ of the etched site was measured immediately after the etching (ΔQ1) and 24 h later (ΔQ2) with QLF. In addition, deft/DMFT, approximal plaque (API), bleeding on probing (mod. PBI), active carious lesions and currently used fluorides were recorded. In a regression analysis for the deft, the use of fluoridated salt (standardized coefficient SC = –0.25) and fluoride gel (SC = –0.37) showed the greatest effect, as did the fluoride gel (SC = –0.26) and gingival bleeding (SC = 0.50) for the number of active carious lesions. The deft and the number of active carious lesions correlated significantly (r = 0.70, p < 0.001). ΔQ1 and ΔQ2 showed a significant statistical correlation with the age-adjusted deft (0.39 < r < 0.52, p < 0.01) and with the number of active lesions (0.42 < r < 0.59, p < 0.01). Correlations between ΔQ and the API, PBI and the fluoride scores were slightly weaker but also statistically significant. In a principal-component analysis, these parameters were approximately identical, indicating a strong relationship between the different variables and ΔQ. This relationship was especially strong for the deft and the active carious lesion scores. In conclusion, these data suggest that the degree of demineralization by etching and its changes with time are associated with caries activity and that this method might be used for the early assessment of caries activity.