Association of DLX3 gene polymorphism and dental caries susceptibility in Japanese children

Objective

In this study, we investigated whether single nucleotide polymorphisms (SNPs) in DLX3 are associated with dental caries susceptibility in Japanese children.

Design

Genomic DNA of 201 Japanese children was extracted from buccal epithelial cells. The subjects were divided into two groups: ‘low level’ group with <10,000 colony forming units (CFU) of Streptococcus mutans/mL saliva (level 0) and ‘high level’ group with ≥10,000 CFU/mL (more than level 1). Each group was further divided according to decayed, missing, filled teeth (dmft) into low caries experience (dmft ≤ 2) and high caries experience (dmft ≥ 3). Seven SNPs in DLX3 were genotyped using TaqMan^® SNP Genotyping Assay.

Results

Statistical significant association was observed between DLX3 (rs2278163) and caries experience in ‘high level Mutans streptococci’ group.

Conclusion

These findings suggest that rs2278163 SNP of DLX3 might be associated with dental caries susceptibility in Japanese children. T and C alleles of rs2278163 SNP may potentially be involved in caries susceptibility and caries protection respectively.     

Effect of three-year consumption of erythritol,xylitol and sorbitol candies on various plaque and salivary caries-related variables

Objective

The objective of the present paper is to report results from oral biologic studies carried out in connection with a caries study.

Methods

Samples of whole-mouth saliva and dental plaque were collected from initially 7- to 8-year-old subjects who participated in a 3-year school-based programme investigating the effect of the consumption of polyol-containing candies on caries rates. The subjects were randomized in three cohorts, consumed erythritol, xylitol, or sorbitol candies. The daily polyol consumption from the candies was approximately 7.5 g.

Results

A significant reduction in dental plaque weight from baseline (p < 0.05) occurred in the erythritol group during almost all intervention years while no changes were found in xylitol and sorbitol groups. Usage of polyol candies had no significant or consistent effect on the levels of plaque protein, glucose, glycerol, or calcium, determined yearly in connection with caries examinations. After three years, the plaque of erythritol-receiving subjects contained significantly (p < 0.05) lower levels of acetic acid and propionic acid than that of subjects receiving xylitol or sorbitol. Lactic acid levels partly followed the same pattern. The consumption of erythritol was generally associated with significantly (p < 0.05) lower counts of salivary and plaque mutans streptococci compared with the other groups. There was no change in salivary Lactobacillus levels.

Conclusion

Three-year consumption of erythritol-containing candies by initially 7- to 8-year old children was associated with reduced plaque growth, lower levels of plaque acetic acid and propionic acid, and reduced oral counts of mutans streptococci compared with the consumption of xylitol or sorbitol candies.     

Caries-preventive effectiveness of fluoride varnish as adjunct to oral health promotion and supervised tooth brushing in preschool children: A double-blind randomized controlled trial

Objectives

To evaluate the effect of biannual fluoride varnish applications in preschool children as an adjunct to school-based oral health promotion and supervised tooth brushing with 1000 ppm fluoride toothpaste.

Methods

424 preschool children, 2–5 year of age, from 10 different pre schools in Athens were invited to this double-blind randomized controlled trial and 328 children completed the 2-year programme. All children received oral health education with hygiene instructions twice yearly and attended supervised tooth brushing once daily. The test group was treated with fluoride varnish (0.9% diflurosilane) biannually while the control group had placebo applications. The primary endpoints were caries prevalence and increment; secondary outcomes were gingival health, mutans streptococci growth and salivary buffer capacity.

Results

The groups were balanced at baseline and no significant differences in caries prevalence or increment were displayed between the groups after 1 and 2 years, respectively. There was a reduced number of new pre-cavitated enamel lesions during the second year of the study (p = 0.05) but the decrease was not statistically significant. The secondary endpoints were unaffected by the varnish treatments.

Conclusions

Under the present conditions, biannual fluoride varnish applications in preschool children did not show significant caries-preventive benefits when provided as an adjunct to school-based supervised tooth brushing with 1000 ppm fluoride toothpaste.

Clinical significance

In community based, caries prevention programmes, for high caries risk preschool children, a fluoride varnish may add little to caries prevention, when 1000 ppm fluoride toothpaste is used daily.     

A New “Silver-Bullet” to treat caries in children – Nano Silver Fluoride: A randomised clinical trial

Background

Untreated dental caries in children remains a public health challenge in poor communities.

Objectives

This prospective controlled clinical trial investigated the effectiveness of a new anti-caries agent, Nano Silver Fluoride (NSF), applied once a year to arrest caries in children.

Methods

One hundred thirty decayed primary teeth were randomly divided into two groups: NSF as the experimental agent and water as the control group. Teeth were clinically diagnosed and treated by one masked examiner and followed up at seven days and five and 12 months by another calibrated examiner who was blinded to the type of treatment. The criteria of the ICDAS II were followed to determine the activity of lesion and the diagnosis of caries. The Pearson's chi-square test was used to compare the groups during different follow-up exams.

Results

At seven days, 81% of teeth in the NSF group exhibited arrested caries, whereas in controls, no teeth had arrested decay (p < 0.001) [PF, prevented fraction = 81%]. After five months, the NSF group had 72.7% with arrested decay, and the control group had 27.4% (p < 0.001) [PF = 62.5%]. At 12 months, 66.7% of the lesions treated with NSF were still arrested, while the control group had 34.7% remaining arrested (p = 0.003) [PF = 50%]. The number need to treat (NNT) at five months was two, and at 12 months, the number was three.Clinical Signi?cance: The NSF formulation is effective to arrest active dentine caries and not stain teeth.

Conclusions

NSF was demonstrated to be effective in arresting caries in children in poor communities.     

Characteristics of child dental neglect: A systematic review

Objective

Neglect of a child's oral health can lead to pain, poor growth and impaired quality of life. In populations where there is a high prevalence of dental caries, the determination of which children are experiencing dental neglect is challenging. This systematic review aims to identify the features of oral neglect in children.

Methods

Fifteen databases spanning 1947–2012 were searched; these were supplemented by hand searching of 4 specialist journals, 5 websites and references of full texts. Included: studies of children 0–18 years with confirmed oral neglect undergoing a standardised dental examination; excluded: physical/sexual abuse. All relevant studies underwent two independent reviews (+/− 3rd review) using standardised critical appraisal.

Results

Of 3863 potential studies screened, 83 studies were reviewed and 9 included (representing 1595 children). Features included: failure or delay in seeking dental treatment; failure to comply with/complete treatment; failure to provide basic oral care; co-existent adverse impact on the child e.g. pain and swelling. Two studies developed and implemented ‘dental neglect’ screening tools with success. The importance of Quality of Life tools to identify impact of neglected dental care are also highlighted.

Conclusions

A small body of literature addresses this topic, using varying definitions of neglect, and standards of oral examination. While failure/delay in seeking care with adverse dental consequences were highlighted, differentiating dental caries from dental neglect is difficult, and there is a paucity of data on precise clinical features to aid in this distinction.

Clinical significance

Diagnosing dental neglect can be challenging, influencing a reluctance to report cases. Published evidence does exist to support these referrals when conditions as above are described, although further quality case control studies defining distinguishing patterns of dental caries would be welcome.     

Sugar-sweetened beverages and dental caries in adults: A 4-year prospective study

Objectives

To explore the association between frequency of consumption of sugar-sweetened beverages (SSB) and caries increment over 4 years in adults. A second objective was to explore whether the association between frequency of SSB consumption and caries increment varied by socio-demographic characteristics and use of fluoride toothpaste.

Methods

Data from 939 dentate adults who participated in both the Health 2000 Survey and the Follow-Up Study of Finnish Adults’ Oral Health were analysed. At baseline, participants provided information on demographic characteristics, education and dental behaviours, including two questions on frequency of SSB consumption. The 4-year net DMFT increment was calculated using data from baseline and follow-up clinical oral examinations. The association was tested in negative binomial regression models and the moderating role of sex, age, education and use of fluoride toothpaste was examined by adding their two-way interaction with SSB consumption to the main effects model.

Results

A positive association was found between frequency of SBS consumption and 4-year net DMFT increment, regardless of participants’ socio-demographic and behavioural characteristics. Adults drinking 1–2 and 3+ SSB daily had, respectively, 31% (Incidence Rate Ratio: 1.31; 95%CI: 1.02–1.67) and 33% (IRR: 1.33; 95%CI; 1.03–1.72) greater net DMFT increments than those not drinking any SSB. None of the four two-way interaction terms was significant (all p > 0.05).

Conclusion

There seems to be a dose–response relationship between frequency of SSB consumption and caries increment in adults. That association was consistent across socio-demographic characteristics, and more importantly, use of fluoride toothpaste.

Clinical significance

Drinking sugar-sweetened beverages on a daily basis is related to greater caries risk in adults.     

A comparison of root caries diagnosis based on visual-tactile criteria and DIAGNOdent in vivo

Objectives

This clinical study aimed to evaluate the validity of using DIAGNOdent in diagnosing root caries, and to assess the sensitivity and specificity of different cut-off DIAGNOdent values in assessing root caries with reference to visual-tactile criteria.

Methods

Exposed root surfaces were assessed by one examiner for root caries on 266 subjects using visual-tactile criteria and DIAGNOdent 2095 after dental scaling. Associations between DIAGNOdent values and visual-tactile diagnosis of root caries were determined. The cut-off level for statistical significance was 0.05. The sensitivity and specificity of DIAGNOdent with difference cut-off points were analysed compared to visual-tactile diagnosis of root caries.

Results

There was significant difference between DIAGNOdent values obtained from sound and carious root surfaces (p < 0.001). On carious surfaces, active root caries obtained significantly higher DIAGNOdent values than inactive root caries (p < 0.001). With increasing cut-off point DIAGNOdent values from 5 to 35, sensitivity decreased from 91.4% to 16.2% and specificity increased from 64.4% to 98.2%. A cut-off point of DIAGNOdent value between 5 and 10 produced the highest combined sensitivity and specificity.

Conclusions

There was a significant difference in DIAGNOdent values between sound and carious root surfaces diagnosed by visual-tactile criteria supporting the validity of DIAGNOdent for assessing root caries. A DIAGNOdent value between 5 and 10 produced the highest combined sensitivity and specificity when visual-tactile assessment of root caries was regarded as the criterion. These findings have implications in using and explaining DIAGNOdent values in assessing root caries.     

Dynamics of oral microbial community profiling during severe early childhood caries development monitored by PCR-DGGE

Objective

To monitor the longitudinal changes in oral microbial diversity of children with severe early childhood caries (S-ECC) compared to caries free (CF) controls.

Methods

Dental plaque samples of 12 children in each group at 8, 14, 20, 26 and 32 months of age were analysed. Total microbial genomic DNA was isolated from each sample, and PCR-denaturing gradient gel electrophoresis (DGGE) analyses were carried out.

Results

The number of bands was significantly higher in the CF group (18.17 ± 4.91 bands) than in the S-ECC group (14.54 ± 5.56 bands) at 32 months of age (P < 0.05). A total of 21 genera were identified in all subjects, and there were no significant differences between the two groups at genus level. DGGE profiles showed that most of the clusters were constructed from one individual over time in the both groups.

Conclusions

The onset of S-ECC is accompanied by a decrease in microbial diversity. The overall composition of the microbiota is highly similar within an individual over time.     

Mechanisms of action of fluoridated acidic liquid dentifrices against dental caries

Objective

This study attempted to clarify the mechanisms of action of fluoridated acidic liquid dentifrices against dental caries.

Design

In the in vitro leg, enamel specimens were submitted to a pH-cycling model, treated with distinct dentifrices (0, 550 μgF/g pH 4.5 and pH 7.0, 1100 or 5000 μgF/g pH 7.0) and analyzed using hardness. Alkali-soluble fluoride (F) deposition was quantified on pre-demineralized specimens treated with the dentifrices. In the clinical leg, 2-to-4-year-old children who had been using liquid dentifrices for 6 months (550 μgF/g pH 4.5 or pH 7.0 or 1100 μgF/g pH 7.0) had their plaque samples collected 5 and 60 min after the last brushing. Fluoride uptake in whole plaque was evaluated.

Results

The reduction of the pH had a partial preventive effect on subsurface hardness loss only. [F] had a significant influence on the deposition of fluoride, surface and subsurface hardness loss. In vivo, the reduction of the pH was able to significantly increase plaque F uptake, leading to similar levels as those found for the neutral dentifrice containing twice [F].

Conclusion

The results obtained from in vitro studies whose design does not include the presence of dental plaque should be interpreted with caution.     

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.     

Prevalence and factors related to dental caries among pre-school children of Saddar town,Karachi, Pakistan: a cross-sectional study

Background

Dental caries is highly prevalent and a significant public health problem among children throughout the world. Epidemiological data regarding prevalence of dental caries amongst Pakistani pre-school children is very limited. The objective of this study is to determine the frequency of dental caries among pre-school children of Saddar Town, Karachi, Pakistan and the factors related to caries.

Methods

A cross-sectional study of 1000 preschool children was conducted in Saddar town, Karachi. Two-stage cluster sampling was used to select the sample. At first stage, eight clusters were selected randomly from total 11 clusters. In second stage, from the eight selected clusters, preschools were identified and children between 3- to 6-years age group were assessed for dental caries.

Results

Caries prevalence was 51% with a mean dmft score being 2.08 (±2.97) of which decayed teeth constituted 1.95. The mean dmft of males was 2.3 (±3.08) and of females was 1.90 (±2.90). The mean dmft of 3, 4, 5 and 6-?year olds was 1.65, 2.11, 2.16 and 3.11 respectively. A significant association was found between dental caries and following variables: age group of 4-years (p-value?²?0.029, RR?=?1.248, 95% Bias corrected CI 0.029-0.437) and 5-years (p-value?²?0.009, RR?=?1.545, 95% Bias corrected CI 0.047-0.739), presence of dental plaque (p-value?²?0.003, RR?=?0.744, 95% Bias corrected CI (?0.433)-(?0.169)), poor oral hygiene (p-value?²?0.000, RR?=?0.661, 95% Bias corrected CI (?0.532)-(?0.284)), as well as consumption of non-sweetened milk (p-value?²?0.049, RR?=?1.232, 95% Bias corrected CI 0.061-0.367).

Conclusion

Half of the preschoolers had dental caries coupled with a high prevalence of unmet dental treatment needs. Association between caries experience and age of child, consumption of non-sweetened milk, dental plaque and poor oral hygiene had been established.

     

Inhibition of tooth erosion by milk containing different fluoride concentrations: An in vitro study

Objectives

This in vitro study assessed the effect of milk containing different fluoride concentrations on tooth erosion.

Methods

Bovine enamel and root dentine specimens were treated with: (1) bovine whole milk with 0 ppm F; (2) 2.5 ppm F; (3) 5 ppm F; (4) 10 ppm F (all after erosion); (5) whole milk with 0 ppm F (before erosion); (6) NaF (0.05% F, positive control, after erosion) or (7) 0.9% NaCl (negative control, after erosion). The specimens were submitted to pH cycles (4× 90 s in soft drink) and treatments for 5 days. The specimens were immersed in the treatment solutions for 1 min (only at the first cycle each day) with further exposition to 1:1 milk:saliva slurry for 10 min. The tooth loss was measured using a contact profilometer and statistically analysed (p < 0.05).

Results

Rinsing with milk before erosive challenge significantly reduced tooth loss compared to negative control (67% and 24% reduction in dentine and enamel loss, respectively) and to milk after erosive challenge, only for dentine. The addition of fluoride to milk also reduced tooth loss compared to negative control, but with no significant differences among fluoride concentrations for enamel and dentine (μm), respectively: 0 ppm (3.63 ± 0.04 and 2.51 ± 0.53), 2.5 ppm F (2.86 ± 0.42 and 1.96 ± 0.47), 5 ppm F (2.81 ± 0.27 and 1.77 ± 0.44), 10 ppm F (2.03 ± 0.49 and 1.68 ± 0.59). There was a negative and significant correlation between [F] and the tooth loss.

Conclusions

Daily rinse with milk containing F is able to reduce both enamel and dentine erosion in vitro.

Clinical significance

Since the prevalence of dental erosion is steadily increasing, rinse with milk or its derivate might be an important strategy to reduce the progression of tooth erosion.     

The prevalence and distribution of dental caries in four early medieval non-adult populations of different socioeconomic status from Central Europe

Objectives

The aim of the study was to map the dental health status in non-adult individuals and to verify whether and how the existence of caries in the non-adult age group is associated with the different socio-economic status of early medieval populations.

Material and methods

We studied the dental remains from the acropolis of the Mikul?ice settlement agglomeration, where members of the higher social classes were buried, and from the Mikul?ice hinterland. Overall, we evaluated 2544 teeth/3714 alveoli of deciduous dentition and 1938 teeth/2128 alveoli of permanent dentition. We determined the number of individuals with dental caries (i.e., caries frequency index, F-CE) and the proportion of teeth/alveoli with caries/ante-mortem tooth loss (i.e., caries intensity index, I-CE).

Results

We found no statistical significant difference in the F-CE values between the Mikul?ice hinterland and the acropolis. In addition, we found no statistically significant difference in the proportion of teeth with carious lesions (I-CE) either in the case of deciduous dentition or in the case of permanent dentition between the hinterland and the acropolis. In the case of permanent dentition, the statistically significant highest proportion of carious lesions (I-CE) was found in Mikul?ice I (p ≤ 0.05). We confirmed an increase in the rate of caries with age.

Conclusions

The level of caries at all of the studied medieval locations was very low. We presume that lifestyle and the associated dietary habits and hygienic practices of the individuals or population groups had a greater influence on dental caries than did the socio-economic status of these individuals.     

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.     

Prevenzione orale in alunni del primo anno della scuola primaria

Objectives

To evaluate the oral health of children enrolled in the first grade of a primary school in L’Aquila (Italy) during the years 2008-2009 and 2009-2010 and to provide them with free-of-charge dental care.

Materials and methods

The study included 105 children, aged 6 ± 1 years (64 males and 41 females). Each child had a dental examination that included (as needed) the application of a plaque revealer, plaque and tartar removal, the application of fluoride, saliva testing, and sealing of fissures. Children were also educated about the importance of oral hygiene.

Results

In 2009, 74 of the 105 pupils enrolled (42 males and 32 females) received treatment, consisting in the application of a plaque revealer (n = 49), tartar and pigment removal (n = 47), application of fluoride gel (n = 42), fissure sealing (n = 36), measurement of salivary pH (n = 66), and salivary bacterial counts (n = 63). In 2010, 36 of the children were retreated. During the first year of the study, the difference between the numbers of enrolled and treated children was linked to the poor cooperation of families; during the second year, the difference was related to logistic and strategic difficulties caused by the earthquake that struck the region on April 6, 2009. The results showed a decrease in the dental plaque index from 58% (2009) to 31% (2010). In addition, the 2009 examination (total no. of children = 74) revealed two filled permanent teeth and 12 permanent teeth that were decayed; in 2010, in 36 children, there were two filled permanent teeth and 9 with caries. In 2010, sealants were reapplied in five cases.

Conclusion

The Dental Department of the University of L’Aquila plans to extend this study to other schools in the same geographic area to decrease the incidence of the most frequent oral diseases, thereby warranting children's right to good health.     

Is non-cavitated proximal lesion sealing an effective method for caries control in primary and permanent teeth? A systematic review and meta-analysis

Objectives

The aim of this study was to perform a systematic review and meta-analysis on the effectiveness of sealing non-cavitated proximal caries lesions in primary and permanent teeth.

Data

Only controlled clinical trials and randomized controlled clinical trials that evaluated the effectiveness of sealing on non-cavitated proximal caries with a minimum follow-up of 12 months were included in the study. The primary outcome should be arrestment/progression of proximal caries evaluated by bitewing radiographs. A risk of bias evaluation based on the Cochrane Collaboration common scheme for bias was carried out for each study. The meta-analysis was performed on the studies considered low risk of bias and with pair-wise visual reading results through RevMan software.

Sources

A comprehensive search was performed in the Systematic Electronic Databases: Pubmed, Cochrane Library, Scopus, IBI Web of Science, Lilacs, SIGLE, and on website Clinical trials.gov, through until June 2013.

Study selection

From 967 studies identified, 10 articles and 3 studies with partial results were assessed for eligibility. However three articles were excluded and our final sample included 10 studies. According to the risk of bias evaluation, six studies were considered “high” risk of bias, and four “low” risk of bias. The forest plot of the meta-analysis showed low heterogeneity (I² = 29%) and a favourable outcome for the Infiltrant. The chance of caries progression when this technique was used was significantly lower (p = 0.002) compared with Placebo.

Conclusion

Our results suggest that the technique of sealing non-cavitated proximal caries seems to be effective in controlling proximal caries in the short and medium term. Further long-term randomized clinical trials are still necessary to increase this evidence.

Clinical significance

Contemporary dentistry is focused in minimally invasive approaches that prevent the destruction of sound dental tissues next to carious lesions. This paper searches for evidence of the efficacy of sealing/infiltrating non-cavitated proximal caries in arresting caries progression both in permanent and primary teeth.     

Anti-cariogenic effect of a cetylpyridinium chloride-containing nanoemulsion

Objectives

The aim of this pilot study was to investigate the anticaries activity of a nanoemulsion composed of soybean oil, water, Triton X-100 and cetylpyridinium chloride.

Methods

Tooth blocks (3 mm length × 3 mm width × 2 mm thickness) were cut from smooth surfaces of selected molar teeth using a water-cooled diamond wire saw. The blocks were randomly assigned to three experimental groups: (A) nanoemulsion, (B) 0.12% chlorhexidine gluconate, and (C) no treatment. The formation of dental caries in human tooth enamel was tested using a continuous flow dual-organism (Streptococcus mutans and Lactobacillus casei), biofilm model, which acts as an artificial mouth and simulates the biological and physiological activities observed within the oral environment. Experimental groups A and B were treated with their respective solutions once daily for 30 s on each occasion, while group C received no treatment. 10% sucrose was supplied every 6 h for 6 min to simulate meals and pH cycling. The experiment lasted for 5 days, and the tooth blocks were harvested and processed for demineralization assessment using transverse microradiography (TMR).

Results

For both lesion depth and mineral loss, statistical analysis indicated that Emulsion was significantly lower than Control and Chlorhexidine, and Chlorhexidine was significantly lower than Control.

Conclusions

We conclude that cetylpyridinium-containing nanoemulsions appear to present a feasible means of preventing the occurrence of early caries.     

Longevity of posterior restorations in primary teeth: Results from a paediatric dental clinic

Objectives

The aim of this retrospective study was to evaluate the longevity of restorations in the posterior primary teeth of children attending to a public paediatric dental clinic and to test the factors associated with failures.

Methods

Patient records of 329 children (162 boys and 166 girls) were used for collecting and analyzing data. A total of 565 restorations in primary teeth were included in the study. All children enrolled in the study were classified as high caries risk. The longevity of restorations from their placement until failure (up to 4 years of follow-up) was assessed using the Kaplan–Meier survival curves with log-rank test. Multivariate Cox regression analysis with shared frailty (p < 0.05) was used to assess the factors associated with failures.

Results

Up to 4 years of follow-up, the annual failure rates were 9.5% for composite fillings, 12.2% for light-cured glass ionomer restorations, and 12.9% for conventional glass ionomer restorations with statistical difference between the materials (p = 0.014). Glass ionomer restorations had a higher risk of failure over time compared with composites (HR 1.86, 95% CI 1.17–2.97). In crude analysis, Class II restorations showed lower survival rate than Class I restorations (p = 0.031) but lost significance after adjustments.

Conclusions

Our findings suggested that the material influenced the survival rate of primary posterior restorations, with composite presenting the best performance.

Clinical significance

Differences were observed between restorative materials with different properties in primary teeth up to 4 years of follow-up. This study provides valuable information regarding the primary teeth posterior restoration longevity in a paediatric population with restorations performed under daily life clinical environment.     

An in situ caries study on the interplay between fluoride dose and concentration in milk

Objectives

This randomized, cross-over in situ study investigated the impact of sodium fluoride dose and concentration in milk on caries lesion rehardening, fluoridation and acid resistance.

Methods

Twenty-eight subjects wore two gauze-covered enamel specimens with preformed lesions placed buccally on their mandibular partial dentures for three weeks. Participants used fluoride-free dentifrice throughout the study and consumed once daily one of the five study treatments: no fluoride in 200 ml milk (0F-200), 1.5 or 3 mg fluoride in either 100 (1.5F-100; 3F-100) or 200 ml milk (1.5F-200; 3F-200). After three weeks, specimens were retrieved. Knoop hardness was used to determine rehardening and resistance to a secondary acid challenge. Enamel fluoride uptake (EFU) was determined using a microbiopsy technique.

Results

A linear fluoride dose–response was observed for all study variables which exhibited similar overall patterns. All the treatments resulted in rehardening, with 0F-200 inducing the least and 3F-100 the most. Apart from 1.5F-200, all the treatments resulted in statistically significantly more rehardening compared to 0F-200. The fluoride doses delivered in 100 ml provided directionally although not statistically significantly more rehardening than those delivered in 200 ml milk. EFU data exhibited better differentiation between treatments: all fluoridated milk treatments delivered more fluoride to lesions than 0F-200; fluoride in 100 ml demonstrated statistically significantly higher EFU than fluoride in 200 ml milk. Findings for acid resistance were also more discerning than rehardening data.

Conclusions

The present study has provided further evidence for the anti-caries benefits of fluoridated milk. Both fluoride dose and concentration appear to impact the cariostatic properties of fluoride in milk.     

Effect of chlorhexidine-thymol varnish on root caries in a geriatric population: A randomized double-blind clinical trial

Objectives

Little is known about the effect of Cervitec^®, a chlorhexidine-thymol varnish, on root caries. Our objective was to determine whether a 3-monthly application of Cervitec^® over 1 year would limit the progress of existing root caries lesions and reduce the incidence of dental root caries in a group of dentate institutionalized elderly, as a complement to their usual oral hygiene practices.

Methods

A double-blind randomized clinical trial was conducted in 68 subjects (34 per group) in two residences in Almería (Spain). Twenty-one subjects with 60 root caries lesions and 25 with 65 lesions, in the Cervitec^® and placebo groups, respectively, completed the study. Varnishes were applied twice in the first week, 1 month later, and every 3 months until the end of the study. Clinical parameters associated with established lesions were determined at baseline and after 6 and 12 months, as was the incidence of root caries lesions.

Results

The clinical evolution of lesions was significantly better in the Cervitec^® group as opposed to the placebo group in terms of width, height, color, and texture. The increase in root caries was significantly lower (p = 0.039) in the Cervitec^® group.

Conclusion

According to these results, Cervitec^® may help to control established root lesions and reduce the incidence of root caries lesion among institutionalized elderly.