| 1. |
- Al-Khateeb, S, et al.
(författare)
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Light-induced fluorescence studies on dehydration of incipient enamel lesions
- 2002
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 36:1, s. 25-30
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Tidskriftsartikel (refereegranskat)abstract
- Changes in the hydration state of enamel affect its optical qualities, such as light scattering and fluorescence. In this study, the rate of fluorescence loss was measured when incipient enamel lesions with different de-remineralization history were left to dehydrate. Four groups of lesions were studied. In groups A, B and C, the lesions were prepared in vitro in an acid-gel system. Group A was kept as control, and groups B and C were remineralized (4 weeks) without and with 1 ppm F in solution, respectively. Group D consisted of natural incipient lesions. Enamel fluorescence was measured for all lesions immediately after removal from water and subsequently at short intervals for 30 min. The change in fluorescence with dehydration varied between the groups. In lesions from groups A and B, it followed a double exponential decrease, while in lesions from groups C and D, it followed a mono-exponential decrease. In all groups, the fluorescence of sound surfaces declined mono-exponentially. The ‘fractional fluorescence difference’, defined as (L<sub>sound</sub> – L<sub>carious</sub> )/L<sub>sound</sub>, became constant after periods of dehydration of about 5, 5, 20 and 5 min for groups A to D, respectively. The observation of the change of fluorescence with dehydration should be taken into consideration when planning studies that use fluorescence as an assessment method. However, it might also be used to gain insight into the properties for fluid transport inside the various lesions, relevant to de-remineralization or fluoride treatments.
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| 2. |
- Angmar-Mansson, B
(författare)
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How to measure the effects of fluoride treatments in clinical trials? Assessment: modern versus traditional methods
- 2001
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 3535 Suppl 1, s. 30-33
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Tidskriftsartikel (refereegranskat)abstract
- In recent years there has been a pronounced change in the epidemiology and disease pattern of dental caries. In the current context, traditional methods of caries assessment, discriminating lesions at cavitation, are clinically inappropriate, and obsolete for research requiring detection of a very early phase of mineral loss. Modern prospective caries studies require sensitive methods permitting the measurement of small changes in tooth mineral content, and objective, quantitative measurements of such changes are now possible in a single caries lesion. For longitudinal studies there are noninvasive methods for assessment of new lesions as well as quantitative changes (progression or regression) in existing lesions. Among as yet unresolved issues are improved methods to assess the current activity of a lesion, methods for detection and quantification of secondary caries and root caries, calibration of methodologies between different research institutes, and methods capable of assessment of the whole continuum in the development of a caries lesion, from initial loss of mineral to cavitation.
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| 3. |
- Ekenback, SB, et al.
(författare)
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Effect of four dental varnishes on the colonization of cariogenic bacteria on exposed sound root surfaces
- 2000
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 34:1, s. 70-74
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to evaluate the effect of four different dental varnishes on the colonization of mutans streptococci, total streptococci and lactobacilli on exposed sound root surfaces. Sixty–five individuals were randomly allotted to one of four groups for treatment with Cervitec<sup>® </sup> varnish containing 1% chlorhexidine and 1% thymol, a thymol varnish or one of two different fluoride varnishes, Fluor Protector and Duraphat. The varnish was applied to three buccal root surfaces in each patient at baseline and after 1 week. Dental plaque from the root surfaces was collected and analysed on four different occasions: at baseline, after 1 week, 1 month and 6 months. The Cervitec varnish caused a statistically significant reduction in the number of mutans streptococci over time. The reduction was significant at 1 week and 1 month relative to baseline. The numbers of total streptococci and lactobacilli were not significantly affected by treatment with Cervitec. No statistically significant difference over time was found for mutans streptococci, lactobacilli or total streptococci after treatment with the fluoride varnishes or the thymol varnish.
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| 4. |
- Hänsel Petersson, Gunnel, et al.
(författare)
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Evaluation of a computer program for caries risk assessment in schoolchildren
- 2002
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Ingår i: Caries Research. - : S. Karger. - 0008-6568 .- 1421-976X. ; 36:5, s. 327-340
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Tidskriftsartikel (refereegranskat)abstract
- The 'Cariogram' is an interactive PC program for caries risk evaluation. It takes into account the interactions between caries-related factors and expresses a graphic assessment of the risk. The aim of this study was to assess the caries risk in schoolchildren using the Cariogram and to evaluate the program by comparing the caries risk assessments with the actual change in DMF. A 2-year prospective study on 446 schoolchildren, 10-11 years old, was conducted. At baseline, data on general health, diet, oral hygiene and use of fluoride were obtained. Saliva analyses included mutans streptococci and lactobacilli counts, buffer capacity and secretion rate. DMFT and DMFS were calculated from records and bitewing radiographs. Scores were entered and caries risk was assessed. Re-examination for caries was done after 2 years. The children were divided into 5 groups according to the assessed caries risk at baseline. Where the Cariogram predicted a 0-20% (high risk), 21-40%, 41-60%, 61-80% and 81-100% (low risk) chance of avoiding new lesions, 8, 35, 42, 73 and 83%, respectively, had no new lesions 2 years later. Logistic regression analyses were carried out. When the Cariogram was included, only two factors, the Cariogram (p < 0.001) and the DMFS at baseline, i.e. past caries experience (p = 0.001), turned out to be significantly associated with caries increment. The Cariogram was the most powerful explanatory variable. When the Cariogram was excluded, lactobacillus count, mutans streptococci, diet intake frequency and DMFS at baseline were significantly associated with caries increment. The Cariogram predicted caries increment more accurately than any included single-factor model. How this finding can be translated into daily practice in the best and most practical way is a matter for future research.
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| 5. |
- Kruger, C, et al.
(författare)
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The effects of egg-derived antibodies to glucosyltransferases on dental caries in rats
- 2004
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 38:1, s. 9-14
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Tidskriftsartikel (refereegranskat)abstract
- The role of <i>Streptococcus mutans</i> in the development of dental caries is well recognized. Important virulence factors include the glucosyltransferases (gtf), essential for production of glucans. We evaluated the anticariogenic effects of orally administered chicken anti-cell-associated (CA) Gtf antibodies in desalivated rats. The animals were infected with <i>S. mutans</i> MT8148R and treated with chicken anti-CA-Gtf egg yolk antibodies (IgY) or nonimmune egg yolk powder. Smooth surface lesions were significantly lower in the anti-CA-Gtf-treated group in comparison to the control groups. Sulcal surface caries was also decreased and of less severity. Our study suggests that chicken anti-CA-Gtf antibodies may have promise as a prophylaxis for high caries risk patients.
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| 6. |
- Lager, Anders, et al.
(författare)
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Cultivatable bacteria in dentine after caries excavation using rose-bur or carisolv
- 2003
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Ingår i: Caries Research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 37:3, s. 206-211
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Tidskriftsartikel (refereegranskat)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.
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| 7. |
- Lindquist, Birgitta, 1952, et al.
(författare)
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Colonization of Streptococcus mutans and Streptococcus sobrinus genotypes and caries development in children to mothers harboring both species.
- 2004
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 38:2, s. 95-103
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Tidskriftsartikel (refereegranskat)abstract
- The major route of early acquisition of mutans streptococci in humans is a vertical transmission from mother to child. The purpose of this longitudinal study was to examine the acquisition, distribution and persistence of Streptococcus mutans and Streptococcus sobrinus in children whose mothers harbored both species and to study the caries incidence in relation to colonization of these bacteria. Fifteen mother-child pairs were followed during the child's first 7 years. Stimulated salivary samples were taken from the mothers and the children. Plaque samples were also collected from the teeth and the tongue of the children. The samples were analyzed by cultivating techniques together with genomic fingerprinting and hybridizing. The caries experience was evaluated on the sampling occasions and retrospectively using the records of caries registrations from the community clinics. During the 7-year period 10 of the 15 children acquired mutans streptococci. Only 4 of them were colonized by both S. mutans and S. sobrinus despite the fact that their mothers harbored both species. In 2 of the children S. sobrinus was found later than S. mutans. A total of 26 genotypes were found in the children and 9 of them were identical to their mothers. New genotypes and a gain-loss pattern were noted especially in the children but also in their mothers. The groups of teeth first positive for the two species were the deciduous molars. The caries experience was low during the study period with 8 children showing no caries.
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| 8. |
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| 9. |
- Mejare, I, et al.
(författare)
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Influence of approximal caries in primary molars on caries rate for the mesial surface of the first permanent molar in swedish children from 6 to 12 years of age
- 2001
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 35:3, s. 178-185
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Tidskriftsartikel (refereegranskat)abstract
- The objective was to assess the influence on the caries rate for the mesial surface of the first permanent molar (6m) of the caries status of the distal surface of the second primary molar (05d) in children from 6 to 12 years of age. The study design was retrospective and included 374 children with an average of 5 sets of bite–wing radiographs. The mean age of the children was 6.7 years when the first bite–wing radiographs were taken and 11.5 years at the time of the latest radiographs included in the study. The approximal surfaces were classified according to a scoring system: 0 = no visible radiolucency, 1= radiolucency in the outer half of the enamel, 2 = radiolucency in the inner half up to the enamel–dentin border, 3 = radiolucency with a broken enamel–dentin border but with no obvious involvement of the dentin, 4 = radiolucency with obvious spread in the outer half of the dentin, and score 5 = radiolucency in the inner half of the dentin. The influence of the status of 05d on the caries rate for 6m (state ≧2) was assessed by using a model for dependence between the two neighbouring surfaces. Presence or absence of approximal caries in the distal surface of the first primary molars (04d) and/or the mesial surface of the second primary molars (05m) at the time of eruption of 6m was also related to the caries rate for 6m. The caries rate for 6m was 15 times higher if 05d had developed enamel/enamel–dentin border caries (state 2 or 3) compared to a radiographically sound 05d (state 0 or 1). No significant increase in the caries rate for 6m was found when 05d had deeper unrestored dentin caries than when 05d had superficial caries (state 2 or 3). Furthermore, for preventing caries in 6m, no benefit could be found from restoring an 05d with dentin caries with amalgam as opposed to leaving the carious lesion unrestored until exfoliation. The caries rates for 6m and 05d were 3.4 and 2.7 times higher, respectively, in the presence of dentin caries/restoration in 04d/05m compared to absence of dentin caries in these molar surfaces at the time of eruption of 6m. In conclusion, the caries rate for 6m depended on the status of 05d and increased 15 times if 05d had enamel/enamel–dentin border caries compared to a sound 05d. Deeper unrestored or restored dentin lesions in 05d did not result in a higher caries rate for 6m compared with more shallow carious lesions in 05d.
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| 10. |
- Shi, XQ, et al.
(författare)
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Comparison of QLF and DIAGNOdent for quantification of smooth surface caries
- 2001
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Ingår i: Caries research. - : S. Karger AG. - 0008-6568 .- 1421-976X. ; 35:1, s. 21-26
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to compare the detection and quantification of smooth surface caries by KaVo DIAGNOdent and quantitative laser/light–induced fluorescence (QLF) using a laser and a lamp as two different light sources. On 40 premolar teeth extracted from adolescents, 71 non–cavitated approximal surfaces were assessed. For QLF, both mean and maximum fluorescence losses were registered. To provide a gold standard for verification, the teeth were then sectioned and lesion depth, stratified on a five–point scale, was determined by histopathology and microradiography. The correlation between the gold standard and the two methods was assessed by Spearman’s rank correlation coefficient. The sensitivity and specificity of the methods for detection of smooth surface caries at D<sub>3</sub> level were also assessed. For lesion depth, correlation with the gold standard was similar for QLF and DIAGNOdent: about 0.85. With respect to dentinal caries detection, sensitivity for DIAGNOdent was 0.75 and specificity 0.96, with a cut–off point of 9. The corresponding values for QLF were 0.94 and 1, with a cut–off value of 20% of fluorescence loss. Spearman’s rank correlation coefficients for enamel mineral loss and QLF and DIAGNOdent, respectively, were 0.76 and 0.67. It was concluded that for quantification of smooth surface caries, the methods are of equal merit, but for scientific purposes, QLF offers the advantage of closer correlation with changes in mineral content.
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