Caries activity test in Mongolian and Japanese children

The main objective of this study was to investigate the relationship between a caries activity test (CAT21 Test), and caries status. The subjects of this study were 419 preschool children, of Okayama City, Japan and, of Ulaanbaatar City, Mongolia. In all, subjects were examined for dental caries using a mouth mirror and probe. Then buccal plaque samples were obtained, incubated at 37°C for 48 hours, and scored as per the manufacturer's instructions for the Cariostat method. The following results were obtained:

• 1.The caries prevalence and mean deft of the two subjects was 55.0% and 3.2 for Japanese, so 92.4% and 6.6 for Mongolians, respectively.
• 2.Results of the CAT21 Test score distribution are as follows: 14% of the Japanese, 7.6% of the Mongolians had a CAT score of 0 (very low risk), 38% of the Japanese, 12.4% of the Mongolians had a 1.0 (low risk), 16.3% of the Japanese, 17.9% of the Mongolians had a 2.0 (middle risk), 25.5% of the Japanese, 36.6% of the Mongolians had a 3.0 (high risk), and 6.2% of the Japanese, 25.5% of the Mongolians had a 4.0 (very high risk) score.
• 3.There was a statistically significant difference in the CAT21 Test scores and dental caries indices of Japanese and Mongolian preschool children (ANOVA P< 0.01, P< 0.001).

From these results, it was suggested that the CAT21 Test is useful in clinical application     

Associations between caries activity,salivary buffer tests and caries increment in Mongolian children

The aim of the study was to evaluate caries increment in combination with a caries activity test (CAT21 Test) and a salivary buffer test (CAT21 Buf Test)—to predict future caries activity in Mongolian preschool children living in Ulaanbaatar City. The effectiveness of combining both tests and deft (decayed, extracted, filled teeth) means was also investigated. The caries prevalence in subjects was 94%, and deft mean value was 6.8. The caries increment after one year was 2.3 teeth. From the distribution of CAT21 Test scores a low risk was found in 38.6% and high risk in 61.4% of the examined children. From the CAT21 Buf Test scores, the high risk (lower buffer capacity) was found in 79.8% of the examined children. When the combination CAT21 Test and CAT21 Buf Test scores were divided into four groups (low-low/lowhigh/ high-low/high-high), the mean def-teeth showed a significant difference among the four groups (ANOVA P < 0.001). One year after the caries increment was evaluated in combination with the CAT21 Test scores and CAT21 Buf Test scores, the low-low risk group showed the lowest mean def-teeth. On the other hand, the high-high risk group showed the highest mean def-tooth (ANOVA P < 0.05). Based on these results, the CAT21 Test and CAT21 Buf Test are useful for clinical application of preschool children in predicting future caries activity. Furthermore, when the CAT21 Test and the CAT21 Buf Test were combined, a higher correlation was shown with the caries status.     

The relationship between the salivary buffer capacity test (CAT21 Buf Test) results and caries status in Mongolian preschool children

This study was conducted to investigate the relationship between results of a salivary buffer test (CAT21 Buf Test) and caries status in 507 preschool children, who were 4–6 years old in Ulaanbaatar City, Mongolia. The prevalence of caries in the preschool children was 96.1%, and the mean deft and d teeth were 8.1 and 7.2, respectively. The mean CAT21 Buf Test score was 53.3% for low risk (high buffer capacity) and 46.7% for high risk (low buffer capacity). When salivary buffer score was divided into two groups (high risk, low risk), mean deft differed a significantly between the two groups (ANOVA P < 0.001). The high risk group had a mean deft higher than that of the low risk group. These results suggest that the CAT21 Buf Test is useful for clinical application in children. Furthermore, when the CAT21 Buf Test score was higher, a higher correlation was shown with caries status.     

Application of an air-abrasive cutting apparatus in the pediatric dental field: Cutting using chitin-chitosan grains

Using an air-abrasive cutting apparatus, cavity preparation of dentin and artificially softened dentin was performed using alumina or chitinchitosan grains as cutting media. As a result of scanning electron microscopic observation, the following findings were obtained:

• 1.In cutting specimens that showed high values for Knoop hardness, alumina grains exhibited excellent cutting effects.
• 2.Regarding specimens after decalcification for each duration, the amount of cutting was significantly larger with alumina grains than with chitin-chitosan grains.
• 3.Regarding specimens cut using chitin-chitosan grains, the deepest cavity preparation was obtained in the specimens decalcified for 12 hours.
• 4.Healthy dentin was effectively cut by the ejection of alumina grains, whereas artificially softened dentin was effectively cut by the selective use of chitin-chitosan grains.
• 5.Adhesion of a large amount of chitin-chitosan grains in the wet dentin specimens was observed.
• 6.The amount of chitin-chitosan grain adhesion was the largest in the wet dentin specimens decalcified 12 or 24 hours.

     

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• The abstract should clearly and concisely describe the study.
• Tips articles do not have abstracts.
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• •Statement of

Abstract

• •None for Tips articles
• •Nonstructured for Clinical Report/Technique articles
• •Structured for Research/Clinical Science articles.
• •Includes Clinical Implications statement.

Material and methods

• •Materials cited with proper information (product, manufacturer, and manufacturer's city/state/country).
• •Methods explained fully, with attention to criteria for quantitative judgment and procedures

     

A comparison of infection control practices of different groups of oral specialists and general dental practitioners

Objective. The purpose of this study was to compare the infection control practices of general dentists and dental specialty groups.Methods. A survey was mailed to 5997 dentists in 1994; the response rate was 70%. The data were analyzed with multiple logistic regression (reference group: general dentists).Results. When sociodemographic influences were taken into consideration, significant predictors of routine infection control practices included all of the following characteristics (odds ratios are in parentheses):

• 1.1. Glove: being younger than 40 years of age (4.5) and being female (5.9).
• 2.2. Using gloves and changing gloves after each patient: being younger than 40 years of age (4.0), being female (3.0), being an oral surgeon (3.6), and being an orthodontist (0.2).
• 3.3. Using gloves, masks, and protective eyewear: being younger than 40 years of age (2.5), being female (2.3), and being an orthodontist, oral physician, or oral pathologist (0.2).
• 4.4. Hepatitis B vaccination for the practitioner: being younger than 40 years of age (5.1).
• 5.5. Hepatitis B vaccination for all clinical staff members: being younger than 40 years of age (1.2), being an oral surgeon (1.7), and being an orthodontist (0.6).
• 6.6. Heat sterilization of handpieces: being younger than 40 years of age (1.5), being an oral surgeon (5.4), and being an orthodontist (0.2).
• 7.7. Taking no additional precautions for patients with HIV: being younger than 40 years of age (1.7), being a periodontist (2.6), being a pedodontist (2.3), and being an oral physician/oral pathologist (4.3).

Conclusion. Improved compliance with recommended infection control procedures is required for all groups and is particularly necessary for orthodontists.     

Dental caries prevalence among Type 1 diabetes mellitus (T1DM) 6- to 12-year-old children in Riyadh,Kingdom of Saudi Arabia compared to non-diabetic children

ObjectiveThe aim of this study was to compare the prevalence of dental caries among groups of 6–12-year-old children with and without Type 1 diabetes mellitus (T1DM) in Riyadh, Saudi Arabia, taking into account oral health behaviour, diet, and salivary parameters.MethodsThe study was designed as a comparable study of dental caries experience between T1DM and non-diabetic groups of children. The total sample size of 209 participants consisted of 69 diabetic and 140 non-diabetic children. Oral hygiene, diet and socio-economic status were collected using a pre-tested questionnaire. Caries was recorded in terms of decayed and filled permanent and primary teeth (DFT/dft). Salivary microbial counts and pH levels were recorded using Caries Risk Test (CRT) kit. Student's t-test, the chi-squared test, linear regression and one-way analysis of variance were performed P-value of 0.05 considered significant.ResultsThe mean dft scores for the diabetic and non-diabetic groups were 3.32 ± 0.78 and 3.28 ± 0.71 (mean ± SD), respectively (p = 0.458). The mean DFT scores for the diabetic and non-diabetic groups were 1.62 ± 0.65 and 1.96 ± 0.65, respectively (p = 0.681). Diabetic children visited dentists more often than non-diabetic children did (p = 0.04), and had lower consumption of both sweets (p = 0.003) and flavoured milk (p = 0.002) than the non-diabetic group. Furthermore, analysis showed that the diabetic children had medium oral pH levels (pH = 4.5–5.5), whereas the non-diabetic children tended to have high (pH ≥ 6.0) oral pH; this difference was statistically significant (p = 0.01). In addition, the diabetic group had higher Lactobacillus levels than the non-diabetic group (p = 0.04).ConclusionThe difference in caries prevalence between the diabetic and non-diabetic children was not statistically significant. The CRT analysis revealed a higher frequency of “critical” pH values (pH = 4.5–5.5) and higher Lactobacillus counts in diabetic children than in non-diabetic children, which indicated a higher caries risk in the former group.     

牙菌斑体外产酸方法测定龋活性研究

目的 探讨龋活性结果与龋病现状之间的关联性。方法 将龋活性试验应用于幼儿匀儿童１５名调查研究。结果 龋生试验结果人群分布比例,（＋）最高占３７％,其次为（＋＋）占２８％,（＋＋＋）占１２％,（－）占２３％,不同龋活性结果之间ｄｆｌ、ｄｆｓ有显著性差异（Ｐ〈０．００１）并且ｄｔ,ｄｓ、ｄｆｔ、ｄｆｓ,ＣＳＩ龋病现状随龋活性结果增加有加重的趋势。结论 牙菌斑龋活性试验是对患者口腔健康教育的重要手段。     

Validity of caries risk assessment programmes in preschool children

Objectives

Various programmes have been developed for caries risk assessment (CRA). Nevertheless, scientific evidence on their validity is lacking. This study aimed to compare the validity of 4 CRA programmes (CAT, CAMBRA, Cariogram, and NUS-CRA) in predicting early childhood caries.

Methods

A total of 544 children aged 3 years underwent oral examination and biological tests (saliva flow rate, salivary buffering capacity and abundance of cariogenic bacteria mutans Streptococci and Lactobacilli). Their parents completed a questionnaire. Children's caries risk was predicted using the 4 study programmes without biological tests (screening mode) and with biological tests (comprehensive mode). After 12 months, caries increment in 485 (89%) children was recorded and compared with the baseline risk predictions.

Results

Reasoning-based programmes (CAT and CAMBRA screening) had high sensitivity (≥93.8%) but low specificity (≤43.6%) in predicting caries in children. CAMBRA comprehensive assessment reached a better balance (sensitivity/specificity of 83.7%/62.9%). Algorithm-based programmes (Cariogram and NUS-CRA) generated better predictions. The sensitivity/specificity of NUS-CRA screening and comprehensive models were 73.6%/84.7% and 78.1%/85.3%, respectively, higher than those of the Cariogram screening (62.9%/77.9%) and comprehensive assessment (64.6%/78.5%). NUS-CRA comprehensive model met the criteria for a useful CRA tool (sensitivity + specificity ≥ 160%), while its screening model approached that target.

Conclusions

Our results supported algorithm-based approach of caries risk modelling and the usefulness of NUS-CRA in identifying children susceptible to caries.

Clinical significance

This prospective study provided evidence for practitioners to select tools for assessing children's caries risk, so that prevention measures can be tailored and treatment plan can be optimised.     

Statement of purpose and methods

The Journal of Evidence-Based Dental Practice has two primary goals:

• •To improve patient outcomes and health
• •To facilitate decision making that results in better patient outcomes, enhanced research planning, better products, and improved policy development.

     

Diet and lifestyle habits associated with caries in deciduous teeth among 3- to 5-year-old preschool children in Jiangxi province,China

Background

The purpose of this study was to investigate the status of caries in deciduous teeth and the effect of diet and lifestyle habits on dental caries among 3- to 5-year-old preschool children in Jiangxi Province, China.

Methods

In total, 2880 cases involving preschool children were selected by stratified cluster sampling. The dental examination methods and criteria followed the WHO guidelines. SPSS 19.0 was used for the statistical analysis. Chi square tests were used to compare the caries prevalence among children with different social characteristics. Non-parametric tests were used to compare the decayed, missing and filled teeth (dmft) index values. Univariate and multivariate regression analyses were used to study the effect of diet and lifestyle habits on dental caries.

Results

The caries prevalence among the 2880 cases of 3- to 5-year-old preschool children in Jiangxi Province, China was 49.13%. There was no gender difference in this rate (P?>?0.05). The caries prevalence increased with age (P?<?0.05). The prevalence of caries in the rural areas was higher than that in the urban areas (P?<?0.05). The deciduous central incisors and deciduous molars had a higher caries prevalence than the other deciduous teeth. According to the multivariate logistic regression analysis, the caries risk increased with living in a rural area, exclusive breastfeeding, greater frequency of daily snacking, high frequency of snacking before sleep and beginning to brush teeth at a late age; the caries risk decreased when parents helped their children brush their teeth.

Conclusion

The caries prevalence among 3- to 5-year-old preschool children in Jiangxi was lower than the level throughout the country and lower than the rate in other developing countries. The children’s diet and lifestyle habits were closely related to dental caries. Parents and children should be more aware of oral health, and parents should help their children develop healthy lifestyle behaviours.

     

The way children look at the upright photograph of a male dentist's face —Analysis using non-contact type of eye movement measuring apparatus FreeView®—

We investigated how child patients take in information from a dentist's face and whether there is any age difference in the way of scanning the face. For this purpose, we used a non-contact type of eye movement measuring apparatus tradenamed FreeView^® and an upright photograph of a male dentist's face as the test image. The subjects consisted of a total of 90 children between the ages of 2 years 11 months and 12 years 11 months. The subjects were divided into three age groups-group A (below 7 years), group B (7–9 years) and group C (10 years or above), and their eye movements were measured and analyzed. Our findings are as follows.

• 1.The saccadic movements to the background of the photo and the fixation points in the background decreased most in group C, followed by group B and group A, in that order.
• 2.The overlapping of saccadic movements to the features of the face (the eyes, nose and mouth) was remarkably in all age groups. However, the subjects did not scan the whole of the appearance of the face (the hair, forehead, cheeks, ears and chin).
• 3.The fixation points on the appearance of the face were unevenly distributed. Many fixation points were found close to the features of the face. This peculiarity was common to all the groups.
• 4.The fixation points on the features of the face increased most in group C, followed by group B and group A, in that order.

     

深圳地区学龄前儿童龋活跃性的研究分析

目的:通过对深圳地区学龄前儿童患龋状况的调查,采用龋病活跃性试验(CAT)检测幼儿龋病活跃性,了解学龄前儿童龋发病情况及龋活跃性与患儿性别、年龄之间的关系。方法:选择深圳地区某幼儿园3~5岁189名幼儿,进行口腔龋齿检查并记录患龋状况,同时采用CAT试剂检测其龋活跃性,分析幼儿患龋状况、CAT、性别及年龄之间的关系。结果:①患龋状况:总患龋率73.02%;总龋失补牙数(dft)3.96±4.06;总龋蚀指数(CSI):11.80±15.53;②性别及各年龄组间dft、CSI无显著性差异(P>0.05);③CAT 3度与其他度之dft、CSI差异有统计学意义(P<0.05)。CAT度数越高,患龋状况越严重;④CAT分度与dft、CSI高度相关(r=0.378,r=0.360,P<0.05)。结论:CAT各度间患龋状况有显著性差异,与患龋状况有高度相关性,提示CAT能反映机体之患龋状况。     

Effect of the combination of ipriflavone and 1α-OH-D3 on debilitant bone in growing rats —Ultrastructural study of endochondral ossification—

Five-week-old male Wistar rats were used to study the effect of dietary therapy with ipriflavone combined with 1α-OH-D₃. Ultrastructural alterations in the metaphysis of debilitated tibia were observed in the growing rats.

• I.Light microscopy findings In the low-calcium diet • standard diet with supplementary ipriflavone and 1α-OH-D₃ group, calcification of the chondral matrix and ossification were active, and the tibia grew normally as in the control group.
• II.Scanning electron microscopy findings In the low-calcium diet • standard diet with supplementary ipriflavone and 1α-OH-D₃ group, dense calcospherites, distinct chondral lacunae, regularly running collagen fibers, and distinct border lines were noted.
• III.Transmission electron microscopy findings In the low-calcium diet • standard diet with supplementary ipriflavone and 1α-OH-D₃ group we found that the osteoblasts were active, the ruffled border of osteoclast was decrease, indicated this osteoclast is inactive.

In conclusion, insufficient calcium intake during the developmental period resulted in debilitated(3etaphysis tibia, whereas dietary therapy using combined ipriflavone and 1α-OH-D3 promoted recovery.     

Adhesive performance of a caries infiltrant on sound and demineralised enamel

Objective

Resin infiltration is considered as a treatment option for initial caries lesions. As cavitated early lesions might require additional restorative intervention, a caries infiltrant might be also used for enamel conditioning prior to composite insertion. This study aimed to analyse the shear bond strength of a flowable composite to sound and demineralised enamel pretreated with a caries infiltrant, a conventional adhesive or a combination of both.

Methods

Flattened bovine enamel specimens (n = 120) were either demineralised (14 d, acidic buffer, pH 5) or remained untreated. Sound and demineralised specimens (each n = 20) were then treated with: (1) 35% phosphoric acid, conventional adhesive, (2) 15% hydrochloric acid, caries infiltrant or (3) 15% hydrochloric acid, caries infiltrant, conventional adhesive. Shear bond strength of a flowable composite was tested after 24 h water storage (37 °C) and statistically analysed (ANOVA, p ≤ 0.05). The mode of failure was assessed microscopically at 25× magnification.

Results

On demineralised enamel, the combination of caries infiltrant and conventional adhesive showed significantly higher shear bond strength values than the conventional adhesive alone, while both being not significantly different from group 2. No significant differences between the groups could be detected on sound specimens. A higher percentage of cohesive failures could be observed in demineralised samples of group 2 (40%) and 3 (65%), while all other specimens presented almost only adhesive failures.

Conclusion

The use of a caries infiltrant before application of a conventional adhesive did not impair bonding to sound and demineralised enamel and might be beneficial as a pretreatment in demineralised enamel.     

Risk assessment of dental caries by using Classification and Regression Trees

Objectives

Being able to predict an individual's risks of dental caries would offer a potentially huge natural step forward toward better oral heath. As things stand, preventive treatment against caries is mostly carried out without risk assessment because there is no proven way to analyse an individual's risk factors. The purpose of this study was to try to identify those patients with high and low risk of caries by using Classification and Regression Trees (CART).

Methods

In this historical cohort study, data from 442 patients in a general practice who met the inclusion criteria were analysed. CART was applied to the data to seek a model for predicting caries by using the following parameters according to each patient: age, number of carious teeth, numbers of cariogenic bacteria, the secretion rate and buffer capacity of saliva, and compliance with a prevention programme. The risks of caries were presented by odds ratios. Multiple logistic regression analysis was performed to confirm the results obtained by CART.

Results

CART identified high and low risk patients for primary caries with relative odds ratios of 0.41 (95%CI: 0.22-0.77, p = 0.0055) and 2.88 (95%CI: 1.49-5.59, p = 0.0018) according the numbers of cariogenic bacteria. High and low risk patients for secondary caries were also identified with the odds ratios of 0.07 (95%CI: 0.01-0.55, p = 0.00109) and 7.00 (95%CI: 3.50-13.98, p < 0.0001) according the numbers of bacteria and existing caries.

Conclusions

Cariogenic bacteria play a leading role in the incidence of caries. CART proved effective in identifying an individual patient's risk of caries.     

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??Objective    Through the analysis of epidemic situation of dental caries in preschool children aged 3-5 years in Baotou city??to discuss the relationship between caries situation and the degree of dental caries activity. Methods    Totally 379 children??male 196??female 183??were selected in 5 kindergartens for dental caries examination with random choice. The dental caries rate??decayed or filled teeth??dft??and caries severity index??CSI??were calculated. Caries activity??CAT?? was measured by caries activity test. Results    The caries rates??dental filling teeth??dft??and caries severity index??CSI??respectively were 56.20%??3.82 and 10.11 in 3-5 years old children in Baotou city. There was no statistically significant difference between male and female??P > 0.05??. The incidence of caries??dft and CSI had no statistically significant difference in all age groups??P < 0.05??. There was no difference in dft and CSI when CAT were at the degree from 0 to 1and from 2 to 3 when each two groups were compared??P > 0.05??. Others had statistically significant difference??P < 0.05??. CAT was positively correlated with dft and CSI at each degree??r = 0.394 and 0.363??P < 0.05??. Conclusion    Caries activity test can reflect the degree of decay effectively and accurately. It is important to screen for high-risk caries patients in children. Reasonable prevention and treatment measures should be developed in response to the caries situation in school-aged children in Baotou city??in order to lay a solid foundation for preventing caries in children.     

Effect of pit and fissure sealants on caries detection by a fluorescent camera system

Objective

The aim of this study was to evaluate the effect of sealant placement on the detection of caries by a fluorescent camera (FC), the Spectra caries detector.

Materials and methods

In a laboratory study, FC images and readings were obtained from 31 extracted teeth, before and following application of clear sealants (Shofu Clear or Delton unfilled), or opaque sealants (3M Clinpro or Delton FS). Teeth were then sectioned and examined for enamel or dentine caries. Using each tooth's true caries diagnosis, the sensitivity and specificity of the FC measurements in detecting dentine caries was calculated. In the clinical study, FC readings were obtained from 41 molars in children prior to and following application of clear sealants.

Results

Following application of Shofu or Delton unfilled there were reductions in the mean FC readings of 10% (p = 0.5) and 8.2% (p = 0.009), respectively. Application of two opaque sealants, 3M or Delton FS significantly reduced mean FC readings 16.2% and 20.8% (p < 0.5), respectively. Although the carious lesions could still be observed in FC images from teeth with opaque sealants there was a significant loss of sensitivity in detecting dentinal caries. Clear sealant application caused an insignificant loss of detection sensitivity. Following application of clear sealants to children's molars there was a small (4.01%) but significant (p < 0.01) reduction in FC readings recorded from these teeth.

Conclusions

The FC can detect caries under clear sealants with little loss of sensitivity. Although lesions can be seen through opaque sealants, loss of sensitivity precludes accurate lesion assessment.     

Minimally invasive caries removal using bio-active glass air-abrasion

Objectives

Alumina air-abrasion has been used to clean teeth and shown to over-prepare access cavity preparation to caries. This study investigated the working hypothesis that bio-active glass air-abrasion is more self-limiting than alumina for minimally invasive caries removal.

Methods

Human extracted molars were scored visually using ICDAS II criteria, divided into sound and carious groups and air-abraded with alumina (n = 10) and bio-active glass (n = 10) in each group, using identical operating parameters. The amount of enamel removed was semi-quantitatively assessed using scanning electron microscopy. Operating time was recorded.

Results

Bio-active glass abrasion removed extrinsic stain and substantial quantities of enamel from all carious fissures but not from sound, where only minimal microscopic surface modifications were observed. Alumina air-abrasion resulted in faster extrinsic stain and clinically substantial enamel removal in both sound and carious groups equally.

Conclusions

Bio-active glass air-abrasion appeared to show a significant self-limiting tendency towards demineralised enamel and extrinsic stain removal but was slower in comparison to alumina air-abrasion. Self-limiting bio-active glass air-abrasion could be used clinically to clean teeth, detect caries and minimally prepare carious enamel as part of MI caries access or placing a sealant restoration.     

Detection of mutans streptococci in plaque samples from Mongolian preschool and school children

Mutans streptococci, in particular Streptococcus mutans and Streptococcus sobrinus, are generally considered to be the principal microbial pathogen of dental caries. The objective of the study was to isolate S. mutans and S. sobrinus, identify them by PCR, and to compare their presence with the caries status and caries risk in Mongolian preschool and school children. Forty one preschool children aged 3–5 years and 40 school children aged 12–15 years were enrolled in this study. As assessed using Cariostat test, 75.6% of preschool children had high caries risk and 37.5% of school children had high caries risk. In preschool children, the prevalence of S. mutans and S. sobrinus were 100% and 36.6%, respectively; 63.4% were positive for S. mutans alone and 36.6% were positive for both S. mutans and S. sobrinus. In school children, the prevalence of S. mutans and S. sobrinus were 100% and 25.0%, respectively; 75.0% carried S. mutans alone and 25.0% had both S. mutans and S. sobrinus. The percentage of children positive for both S. mutans and S. sobrinus in the high caries risk group were significantly higher than those in the low risk group of either preschool (42.0% vs. 10.0%, P< 0.001) or school children (46.6% vs. 12.0%, P<0.001). Moreover, the caries status of children positive for both S. mutans and S. sobrinus were significantly higher than those positive for S. mutans alone (P< 0.01 for preschool children, and P< 0.05 for school children).