Showing papers in "Caries Research in 2003"

A life course approach to assessing causes of dental caries experience: the relationship between biological, behavioural, socio-economic and psychological conditions and caries in adolescents.

Abstract: The objective of this study was to further elucidate the relationship between relevant biological, behavioural, socio-economic and psychological conditions, experienced in very early life and along the life course, and dental caries experience using the life course approach. A two-phase study was carried out in Brazil. In the first phase, 652 13-year-olds were clinically examined and interviewed. In the second phase, 330 families were randomly selected for interview to collect information on the teenagers' early years of life. Clinical assessment included dental caries, periodontal and traumatic dental injury status. The data analysis involved multiple logistic regression analysis. Adolescents born in a non-brick house, those with a low birth weight and those who were the second or later child in the family were statistically significantly more likely to have a high DMF-T. In conclusion, the results of this study show that there is an association between socio-economic and biological factors in very early life and levels of caries in adolescents.

Performance of conventional and new methods for the detection of occlusal caries in deciduous teeth.

Abstract: The aim of this study was to compare, in vitro, the performance of different conventional diagnostic techniques with the laser-based device, DIAGNOdent, for diagnosis of occlusal caries in deciduous teeth. 95 deciduous teeth with macroscopically intact occlusal surfaces were selected. All teeth were assessed by the following techniques: visual inspection (VI), visual inspection with magnification (VIM), visual inspection combined with light pressure probing (VIP), bitewing radiography (BW) and the DIAGNOdent (DD). Caries extension was assessed by histology. DIAGNOdent showed, in comparison with the conventional clinical methods, a significantly improved ability (p < 0.05) to detect dentinal lesions (D(3) or D(4)) in deciduous teeth and an overall performance similar to that obtained in previous studies on permanent teeth. There was no statistically significant difference between VIM and DD in detecting caries confined to enamel (D(2)). DD performed better at D(2) level than the other methods. The intraexaminer kappa scores for DIAGNOdent were 0.76-0.86 (D(2)) and 0.77-0.85 (D(3)), respectively. It was concluded that DIAGNOdent could be used as an additional tool in the detection of occlusal caries in deciduous teeth and its good reproducibility should enable the laser device to monitor the caries process over time.

Host-derived proteinases and degradation of dentine collagen in situ.

Abstract: Dentine root caries is a process of demineralization and degradation of the organic matrix by proteinases. In this in situ study, the presence and activity of the matrix metalloproteinases 1, 2 and 9

An in vitro comparison of a combined FOTI/visual examination of occlusal caries with other caries diagnostic methods and the effect of stain on their diagnostic performance.

Abstract: The aims of this in vitro study were to compare the combination of FOTI and visual inspection to other diagnostic methods for the detection and evaluation of the depth of occlusal caries and assess the effect of stain on diagnostic performance. Five diagnostic methods (combined FOTI/Visual (CFV), Visual, FOTI, DIAGNOdent and Electrical Caries Monitor) were considered. Histological validation was performed in the 152 occlusal molar sites (111 teeth) using 350-microm sections and a stereomicroscope. The rank correlation coefficients with histology ranged from 0.42 (DIAGNOdent) to 0.66 (CFV). The area under the ROC curves (AUC) for enamel lesions ranged from 0.82 (ECM) to 0.88 (CFV) and from 0.81 (DIAGNOdent) to 0.91 (CFV) for dentine lesions. The AUC at the dentine level for CFV and FOTI were similar (p > 0.05), but the AUC for CFV was significantly greater than for visual (p < 0.001), DIAGNOdent (p = 0.005) and the ECM (p = 0.04). FOTI was found to be particularly useful for the detection of dentine lesions. The exclusion of stain and brown spot lesions improved performance for all methods. It is concluded that CFV is useful for the determination of occlusal lesion depth and that in the presence of stain and brown spot lesions different cut-off points may be required for the ECM and DIAGNOdent to identify dentine lesions.

Clinical study of the use of the laser fluorescence device DIAGNOdent for detection of occlusal caries in children.

Abstract: Diagnosis of non-cavitated occlusal caries is generally considered problematic. The aim of this study was to evaluate the utility of the laser fluorescence device DIAGNOdent as part of routine dental check-ups in children. A total of 613 occlusal surfaces on permanent molars and 436 surfaces on primary molars in children aged 7–8 (n = 55) and 13–14 years (n = 54) were examined visually, using DIAGNOdent and for most 13- to 14-year-olds also using radiographs. The teeth were not cleaned professionally before examination. To provide a gold standard for carious teeth, the depth of the caries lesion was determined in those lesions that were judged visually to need opening by drilling (51 teeth). The higher the visual score, the higher were the mean DIAGNOdent values, but in each visual category the variation among values was large. The presence of a clear sealant did not affect DIAGNOdent measurements. The values for permanent and primary molars differed slightly. For permanent teeth, Youden’s index value was highest (60%) at a cut-off value of 30, which indicates that the overall performance for DIAGNOdent in detecting dentinal caries was best at this point. Using this cut-off, sensitivity was 92% and specificity 69% with visual examination for validation, while sensitivity was 92% and specificity 82% with validation by fissure opening. Of the three methods, radiographic examination was the least accurate. In routine dental check-ups of children, DIAGNOdent appears to be useful as an adjunct to visual examination.

Caries progression and inhibition in human and bovine root dentine in situ

Abstract: Since the use of bovine instead of human dentine to evaluate cariogenic and anticariogenic substances is not well established, this in situ study was conducted Eleven volunteers wore palatal acrylic devices containing 4 dentine slabs (2 human and 2 bovine) Sucrose solution (20%) was dripped over all slabs 4 times a day, simulating a cariogenic challenge Dentifrice slurries, fluoridated or not, were dripped over specified dentine slabs 3 times a day to evaluate caries reduction After 14 days, the biofilm formed on the dentine slabs was collected for microbiological analysis In dentine, mineral loss (ΔZ) and lesion depth (LD) were determined by cross-sectional microhardness and by polarized light microscopy, respectively The total streptococci and mutans streptococci counts in the biofilm formed either on human or on bovine slabs, whether treated or not with fluoride dentifrice, were not statistically different The ΔZ and the LD values of dentine treated with fluoride dentifrice were significantly lower than the values of dentine treated with non-fluoride dentifrice The differences in the ΔZ and LD values between the human and bovine dentine were not statistically significant The results suggest that bovine dentine can be used instead of human to evaluate caries development and inhibition

Systematic Review of Studies Comparing the Anti-Caries Efficacy of Children’s Toothpaste Containing 600 ppm of Fluoride or Less with High Fluoride Toothpastes of 1,000 ppm or Above

Abstract: Objective: To determine the clinical effectiveness of low fluoride (F) toothpastes, containing 600 ppm or less, with toothpaste containing 1,000 ppm or more fluoride in preventing d

Comparative study of wear of enamel induced by alternating and simultaneous combinations of abrasion and erosion in vitro.

Abstract: Two types of interaction of erosive and abrasive forces with human enamel were analysed in an in vitro study. To simulate toothbrushing or chewing after an acidic challenge, enamel specimens were eroded in 0.3% citric acid (pH 3.2), then brushed with or without silica abrasive. To simulate simultaneous erosion and abrasion, as would occur during chewing of abrasive acidic food, enamel specimens were abraded in a toothbrushing machine, with and without silica abrasive, while immersed in citric acid. Enamel wear was measured by profilometry. In both experiments the combination of erosion and abrasion resulted in significantly greater wear than erosion alone, but no significant differences in wear after brushing with or without abrasive were found. Simultaneous erosion and abrasion resulted in about 50% more wear than alternating erosion and abrasion. It is concluded that softened enamel is highly unstable and potentially easily removed by short and relatively gentle physical action. Chewing of acidic foods with some abrasive properties might cause enhanced tooth wear.

Fluoride, beverages and dental caries in the primary dentition

Abstract: Knowledge concerning risk factors for primary dentition caries in young children is incomplete. Models are presented for caries development using longitudinally gathered fluoride exposure and dietary intake data in the Iowa Fluoride Study. Primary tooth caries examinations were conducted at age 5. Dietary (beverage) and fluoride exposure data were gathered longitudinally from age 6 weeks through 4 years (n = 291); 23% had decayed or filled surfaces. Logistic regression revealed that beverage components and toothbrushing made unique contributions to caries experience. Water consumption (36-48 months), milk consumption (24-36 months), and fluoridated toothpaste brushings (36-48 months) were negatively associated with caries; sugared beverages and milk (6 weeks to 12 months) were positively associated. Although fluoride exposure is important, sugared beverages contribute substantially to caries risk, while water and milk consumption and frequent toothbrushing early can have protective effects.

Protective influence of experimentally formed salivary pellicle on enamel erosion. An in vitro study.

Abstract: The purpose of this study was to evaluate dental erosion in 0.1 and 1.0% citric acid in vitro by several different methods and to assess the protective potential of experimentally formed salivary pell

Inhibitory Effects on Selected Oral Bacteria of Antibacterial Agents Incorporated in a Glass Ionomer Cement

Abstract: The objectives of the study were to investigate the antimicrobial efficacy, over time, of combining antibacterial agents with a glass ionomer cement (GIC). This was assessed using an agar diffusion test. Chlorhexidine hydrochloride, cetylpyridinium chloride, cetrimide and benzalkonium chloride were added to Fuji IX GIC at 0, 1, 2 and 4% w/w. Antibacterial-GIC specimens were placed onto agar plates inoculated with one of six bacterial species (Streptococcis, Lactobacillus, and Actinomyces, two each) and the area of inhibition calculated after 24 h incubation. The experiment was repeated weekly and at week 11 the surface of the specimen was abraded prior to replacing on inoculated agar plates. Control specimens of the GIC produced no bacterial inhibition. The antibacterial-GIC combination specimens showed significant inhibition which decreased at different rates over the test period. Resurfacing of the specimens showed a dramatic increase of antibacterial action similar to levels produced on week 1. CT-GIC showed the greatest (p < 0.005) inhibitory effect throughout the experimental period for 4 out of 6 test bacteria. The addition of antibacterial agents to Fuji IX creates a GIC material with significant antimicrobial action in vitro which is dependent on concentration and type of antibacterial agent, and appears to be associated primarily with a release of the antibacterial from the surface layer of the specimen.

In vivo effectiveness of laser fluorescence compared to visual inspection and radiography for the detection of occlusal caries in primary teeth.

Abstract: The purpose of this study was to evaluate the in vivo effectiveness of laser fluorescence compared to visual inspection and radiography for the detection of occlusal caries in primary teeth. Fifty sites from 30 molars in 29 patients were selected and evaluated under standardized conditions by 2 previously trained examiners according to the 3 diagnostic methods. Histological examination served as gold standard after exfoliation or extraction. Values obtained for sensitivity, specificity and accuracy were 0.60, 0.90 and 0.73 for laser fluorescence, 0.82, 0.85 and 0.84 for visual inspection and 0.62, 0.73 and 0.67 for radiography, respectively. Considering only dentinal caries, values were 0.73, 0.95 and 0.90 for laser fluorescence, 0.61, 1.00 and 0.90 for visual inspection and 0.96, 0.81 and 0.85 for radiography, respectively. We conclude that for the detection of occlusal caries in primary molars laser fluorescence presents a similar accuracy when compared to visual inspection and radiography, although visual inspection showed better values for sensitivities for both enamel and dentin lesions.

Ten-Year Incidence of Tooth Loss and Dental Caries in Elderly Swedish Individuals

Abstract: There has been a significant reduction in edentulism and the elderly retain more teeth into old age. The 10-year incidence of tooth loss, coronal and root caries was studied in a random sample of inhabitants of Goteborg, who were 55, 65 and 75 years old at baseline. Of the 208 persons examined at baseline, 102 (49%) participated in the follow-up examination: 56, 37 and 9, respectively, in the different age groups of 65, 75 and 85 years. In addition, for the purpose of time-trend comparisons, a new random sample of 98 individuals aged 55 years was examined. The mean numbers of remaining teeth were 24, 23, 17 and 14, respectively, in the age groups of 55, 65, 75 and 85. The corresponding mean numbers at baseline were 23, 19 and 17, respectively, in those subjects who were then 55, 65 and 75 years old. Forty-eight percent had lost no teeth during the 10-year period, while 13% had lost more than 2 teeth. The major reason for tooth extraction was dental caries and it was found in 60% of all cases. The incidence of coronal caries decreased, while that of root caries increased with age (p < 0.01). Comparing the same age groups, the frequency of root caries had decreased during the 10-year period. It could be concluded from this study that elderly people were determined to retain their teeth for as long as possible, but dental caries may be a problem among the very old.

Terahertz pulse imaging : a pilot study of potential applications in dentistry

Abstract: The improvement in the detection of caries offers the possibility for dramatic improvement in dental healthcare. Current caries detection rates suggest that there may be scope for improvement. This paper describes a preliminary study to examine applications of terahertz pulse imaging (TPI) to caries detection. We present results for the detection of early stage caries in the occlusal enamel layer of a range of human tooth cross sections using TPI. Higher attenuation of terahertz radiation was observed in carious enamel as compared with healthy enamel. Hypomineralised enamel had different absorption spectra and contrast compared to carious enamel in TPI images. These results have important implications for extending TPI to other medical imaging applications where both early diagnosis and safety issues are important.

Six-Year Success Rates of Occlusal Amalgam and Glass-Ionomer Restorations Placed Using Three Minimal Intervention Approaches

Abstract: The present randomised clinical trial was aimed at comparing three minimally invasive restorative treatment approaches for managing dental caries in occlusal surfaces using a non-gamma-2 amalgam and a low-viscosity glass-ionomer as the restorative material. The treatment approaches tested in parallel groups were: conventional in a university setting, modified-conventional and ultraconservative (Atraumatic Restorative Treatment, ART) approaches in a field setting. A split-mouth design was used in which the two restorative materials were randomly placed in 430 matched contralateral pairs of permanent molar teeth. A total of 152 children from five primary schools were recruited and treated by a dental therapist. The restorations were evaluated after 6 years by 2 calibrated independent examiners. The 6-year successes for all occlusal amalgam and glass-ionomer restorations were 72.6 and 72.3%, respectively. There were no statistically significant differences observed between the successes for both amalgam and glass-ionomer restorations placed either by the ART (68.6%, with 95% CI = 61-76%) approach or by the conventional (74.5%, with 95% CI = 65-82%) and the modified-conventional (75.8%, with 95% CI = 67-83%) approaches after 6 years. There was also no statistically significant difference observed between the successes of occlusal ART restorations with glass-ionomer (67.1%, with 95% CI = 56-77%) and occlusal conventional restorations with amalgam (74%, with 95% CI = 61-85%) after 6 years. 'Restoration fracture/marginal defects' and 'loss of material' were the most common causes for failure. The former was more often recorded in amalgam restorations and the latter in glass-ionomer restorations. Secondary caries was observed for 2% of glass-ionomer and for 10% of amalgam restorations. This difference was statistically significant (p = 0.001). The ART approach using glass-ionomer performed equally well as conventional restorative approaches using electrically driven equipment and amalgam for treating dentinal lesions in occlusal surfaces after 6 years.

The effect of variable energy input from a novel light source on the photoactivated bactericidal action of toluidine blue O on Streptococcus Mutans.

Abstract: Although the combination of toluidine blue O (TBO) dye and laser light at a wavelength of 633 nm has a bactericidal effect, light from laboratory lasers can only be directed externally at a bacterial colony or suspension. In this study a novel delivery system guided the laser light to an 800-µm diameter spherical tip (an isotropic tip) from which light radiated producing a uniform sphere of light within the colony or suspension. The system was highly effective in killing TBO-treated Streptococcus mutans NCTC 10449 in stirred planktonic suspension, killing at least 109 cfu/ml. Antibacterial action increased as the delivered energy dose increased. Energy doses of 1.8 J or more produced 100% kills and log reductions of 8–10 cfu/ml. Neither TBO dye nor light alone had a significant antibacterial effect under the experimental conditions used. The existence of a threshold energy, i.e. a minimum energy required before bactericidal action occurred, could not be demonstrated.

The acid-tolerant microbiota associated with plaque from initial caries and healthy tooth surfaces

Abstract: The intent of this study was to compare the inherent acid tolerance of bacteria in samples of dental plaque from tooth sites in subjects with and without initial caries. Plaque was collected from approximal surfaces showing early enamel caries and from healthy tooth surfaces in the same subjects, as well as from enamel surfaces of caries-free individuals. In addition to plating on blood agar, the plaque samples were plated directly on non-selective solid agar medium buffered to pH 7.0, 6.0, 5.5, 5.0, 4.5 and 4.0 to avoid any loss of adaptation to acid during primary isolation of plaque bacteria. The results showed that approximately 50% of the total cultivable plaque microbiota from caries, as well as healthy tooth sites, was able to grow at pH 5.5 and 1% at pH 5.0, pH values regarded as critical for the demineralization of tooth enamel. At pH 5.0, members of the genus Streptococcus were the dominant group, but mutans streptococci accounted for less than half of the streptococcal viable count. The other acid-tolerant streptococcal isolates included Streptococcus anginosus, Streptococcus constellatus, Streptococcus gordinii, Streptococcus intermedius, Streptococcus mitis, Streptococcus oralis, Streptococcus salivarius and SStreptococcus sanguis. Analysis of the results indicated that the mutans streptococci in dental plaque were highly variable with respect to acid tolerance, and that both caries and healthy sites harboured significant numbers of mutans streptococci that were not acid-tolerant.

Clinical Trial of an Air-Abrasion/Chemomechanical Operative Procedure for the Restorative Treatment of Dental Patients

Abstract: The aim of this study was to investigate whether caries removal with air-abrasion/Carisolv gel is an acceptable and viable alternative in the treatment of dental patients. Twenty-two patients were treated with conventional methods (local anaesthetic injection/drill) followed by alternative treatment (air-abrasion and Carisolv gel) in a general practice setting, by the same operator. The participants' pre-operative anxiety levels were measured using the Modified Dental Anxiety Scale. Their postoperative levels of anxiety/dislike for aspects of both conventional and alternative treatments were assessed using a visual analogue scale. Levels of anxiety/dislike for both treatments were compared and statistically analysed. Results showed 100% of subjects were concerned about several aspects of conventional treatment including pain/discomfort on injection, taste of anaesthetic, length of time tissues remained numb, noise of the drill, its sensory vibrations and water coolant. However, 75% of the study population were happy with all aspects of the air-abrasion technique including dust, pain/discomfort and vibrations produced. Overall, the study population found Carisolv gel to be an acceptable alternative method of caries removal in terms of time taken, pain/discomfort and taste. There were statistically significant differences between patients' perceptions of various aspects of the two treatment methods. All participants found the alternative treatment to be pain-free, quicker and overall more acceptable compared with conventional treatment. The conclusion drawn from the study was that air-abrasion/Carisolv gel treatment was a well-accepted and viable alternative to conventional local anaesthetic injection and drill for dental patients.

Longitudinal study of the three-dimensional development of subsurface enamel lesions during in vitro demineralisation.

Abstract: A longitudinal study was made of the 3D development of subsurface enamel lesions in whole human molars. X-ray microtomography (XMT) was used to measure the 3D distribution of linear attenuation coeffi

In vitro study of remineralization of dentin: effects of ions on mineral induction by decalcified dentin matrix.

Abstract: We examined the effects of various ions on the mineralization of dentin matrix in vitro. Demineralized dentin matrix was incubated in a metastable calcium phosphate solution with or without silicate, fluoride, calcium, phosphate, magnesium or silver. Insoluble dentin matrix induced mineral formation after incubation for 10.2 h in the metastable solution without added ions. Silicate at 5 microM and fluoride at 40 microM significantly reduced the mineral induction time. At least 200 microM calcium or 100 microM phosphate was required to promote mineral induction. Conversely, magnesium and silver concentrations as low as 10 and 2 microM inhibited mineral induction. The mineral induced by each sample after incubation for 24 h was identified by its X-ray diffraction pattern as apatite. We concluded that silicate is a stronger inducer of remineralization of dentin matrix than fluoride, calcium or phosphate, and that magnesium and silver inhibit the induction of remineralization of dentin matrix.

Susceptibility of Enamel Surfaces to Demineralization after Application of Fluoridated Carbamide Peroxide Gels

Abstract: The aim of the present study was to evaluate the effect of experimental, fluoridated carbamide peroxide gels on formation of erosively induced demineralization of enamel. Seventy-five bovine enamel specimens were polished for microhardness determination and evenly distributed among 5 groups (A-E). The specimens were treated with 10% carbamide peroxide gel (8 h) and subjected twice to remineralization for 2 h in artificial saliva and demineralisation for 90 s in 1% citric acid, pH 2.2. The cycles of treatment with carbamide peroxide and twofold re- and demineralization were repeated three times. The carbamide peroxide gels were different in pH and fluoride content. Gel A (pH 7.0) and gel B (pH 5.7) were fluoridated (0.5% F), gel C (pH 7.0) and gel D (pH 5.7) were not fluoridated. In control group E the samples were not treated with a gel, but stored in 100% humidity for 8 h instead. Knoop microhardness of the specimens was assessed directly after polishing, and after each carbamide peroxide treatment and demineralization. All specimens showed a loss of microhardness at the end of the experiment. After 3 days, the controls revealed a significantly lower hardness loss compared to the specimens treated with the carbamide peroxide gels. Surface softening was significantly lower for the specimens of group A compared to the remaining groups (B-D), which were not significantly different among each other. It is concluded that treatment with either fluoridated or unfluoridated carbamide peroxide gels, at either neutral and acidic pH, renders enamel more susceptible to demineralization. Use of a fluoridated neutral gel decreases the degree of surface softening compared to the other gels investigated.

Demineralization of Er:YAG and Er,Cr:YSGG Laser-Prepared Enamel Cavities in vitro

Abstract: The aim of the present study was to establish whether cavity preparation by means of an erbium laser with efficient water cooling is capable of reducing the susceptibility of the prepared dental ename

Cultivatable bacteria in dentine after caries excavation using rose-bur or carisolv.

Abstract: To measure the amount of viable bacteria after excavation using conventional rose-bur or the chemo-mechanical Carisolv method, a total of 22 lesions were analyzed (one vital tooth per patient) in this open, controlled and randomized study. Two samples per lesion were taken under aseptic conditions using a rose-bur, one superficially in the caries lesion and one after completed excavation. In in vitro tests more material was collected from the hard caries free dentine as compared to the carious dentine. The samples were incubated on blood agar (aerobically and anaerobically), Rogosa (SL) agar and mitis salivarius (MS) agar. For blood agar (aerobic) both methods resulted in a significant decrease in CFU, for blood agar (anaerobic) and MS agar only the Carisolv method resulted in a significant decrease in CFU and for SL agar neither method resulted in a significant decrease in CFU. Comparing CFU before and after excavation, a considerable reduction of CFU was seen ranging from 10(1) to 10(4). Comparing the excavation methods, there were no significant differences, except in the case of blood agar (aerobic), which showed that Carisolv excavation was more effective in reducing CFU. This study indicated that bacterial sampling collected more material from hard dentine as compared from soft. Remaining bacteria after excavation were low in both groups. The Carisolv method seemed to remove bacteria at least up to and possibly beyond the extent of conventional drilling.

Effect of a calcium carbonate-based dentifrice on enamel demineralization in situ.

Abstract: Since the effect of calcium carbonate (CaCO3) based dentifrice on enamel demineralization is not clearly established, it was evaluated using the IEDT model described by Zero’s group in 1992

Preliminary in vitro assessment of erosive potential using the ultra-micro-indentation system.

Abstract: The aim of this study was to measure the change in hardness and modulus of elasticity of enamel and dentine in primary teeth using the ultra-micro-indentation system (UMIS) after exposure to potentially erosive beverages and to relate the changes to the chemical composition of the test beverages. Primary molar teeth were sectioned and polished. Indentations were made in enamel and dentine prior to and then after exposure to one of four beverages: distilled water (control), orange juice, Orange Cordial, Fanta((R)) and a 'toothfriendly' Tropical Orange Cordial (Ribena((R))). Each beverage was then analysed. Fanta and Orange Cordial were the only test beverages to show a statistically significant reduction in the enamel hardness in comparison to the control and only Fanta showed a significant reduction in dentine hardness. None of the test beverages significantly reduced the modulus of elasticity of either enamel or dentine. Statistically the pH, phosphate and fluoride concentrations of the beverages were correlated with softening of enamel. Calcium concentration and titratable acidity were correlated with softening of dentine. The UMIS offers another method of measuring the basic mechanical properties of enamel and dentine. This is useful in predicting the erosive potential of substrates. It is likely that the pH, titratable acidity, fluoride, phosphate and calcium content of beverages are all important in determining the potential erosiveness of beverages.

Evaluation of the Effectiveness of Laser Fluorescence in Monitoring in vitro Remineralization of Incipient Caries Lesions in Primary Teeth

Abstract: The purpose of this investigation was to examine the effectiveness of laser fluorescence for monitoring in vitro remineralization of caries lesions. Seventeen natural enamel lesions in primary molars were each cut into two parts. One part was exposed, at room temperature, to a remineralizing solution (experimental) and the other part to water (control) for 28 days. Laser fluorescence readings were taken at the beginning of the experiment and during the experiment. At the end of the experiment, lesion depth in the experimental halves was significantly less than in the control halves (p < 0.01), suggesting that remineralization had occurred. However, the laser fluorescence readings showed no statistically significant changes during the experiment, either in the experimental or control halves. We conclude that laser fluorescence was not able to detect in vitro remineralization of natural incipient caries lesions of primary teeth.

Metabolic control as a modifier of the association between salivary factors and dental caries among diabetic patients.

Abstract: The aim here was to analyze the role of metabolic control as a modifier of the association of salivary factors with dental caries among diabetic patients. Cross-sectional data were gathered from 149 i

Diagnostic outcome of methods frequently used for caries validation. A comparison of clinical examination, radiography and histology following hemisectioning and serial tooth sectioning.

Abstract: The aim of this study was to compare the caries diagnostic outcome of four methods frequently used as validation for dental caries. The diagnostic outcome of clinical examination (CL), radiography (RA), and histology after serial tooth sectioning (HI-serial) on 373 approximal and 158 occlusal surfaces was compared, and furthermore histology after hemi- (HI-hemi) and serial sectioning on another 113 approximal and 53 occlusal surfaces was compared. Two thresholds for each method (CL: (1) sound vs. all caries scores, and (2) non-cavitated vs. cavitated lesions; RA and HI: (1) sound vs. all caries scores, and (2) no dentine vs. dentine lesions) were evaluated. In general, large differences in diagnostic outcomes were observed with the various methods. At threshold 1, CL resulted in significantly more lesions than both RA and HI-serial on approximal surfaces, and than RA on occlusal surfaces. At threshold 2, no significant differences between CL, RA and HI-serial were found on approximal surfaces, but on occlusal surfaces significantly more lesions were diagnosed with RA and HI-serial than with CL. Significantly more occlusal lesions were found by HI-serial than by RA at both thresholds 1 and 2. On approximal surfaces, a similar result was found only at threshold 1. On approximal surfaces, significantly more lesions were diagnosed with HI-serial than with HI-hemi at both thresholds 1 and 2. On occlusal surfaces the same was found only at threshold 1. The intra-observer reproducibility was higher using HI-serial than using RA and CL.

A new selective medium for Streptococcus mutans and the distribution of S. mutans and S. sobrinus and their serotypes in dental plaque.

Abstract: A new selective medium (MS-MUT) was developed for the isolation of Streptococcus mutans from clinical specimens. The average growth recovery of S. mutans on MS-MU

Xylitol Inhibition of Acid Production and Growth of Mutans Streptococci in the Presence of Various Dietary Sugars under Strictly Anaerobic Conditions

Abstract: The aim of this study was to investigate the inhibitory effect of xylitol on the growth of and acid production by mutans streptococci in the presence of various dietary sugars, and the relationship be