Bacterial factors of cariogenicity (literature review)

OBJECTIVE

Introduction: According to the 2003 WHO report, dental caries affects from 60% to 90% of school-age children and adults that makes it one of the most common diseases worldwide. The aim was to systematize data about the modern conception of plaque formation and role of microorganisms in its development.

PATIENTS AND METHODS

Materials and methods: Biblosemantic, 50 medical literature sources were systematically reviewed as the material for the research.

RESULTS

Review: According to Miller's theory, oral microorganisms can decompose dietary carbohydrates into acids, which in turn dissolve the calcium phosphates found in the enamel, causing it demineralisation Along with Streptococcus mutans, nowadays some other bacteria as Streptococcus sorbinus, Lactobacillus spp. and Actinomyces spp. have been well studied as caries contributors. However, the disease is related to plaque-mediated, because a much larger number of normal oral microflora representatives are involved in creating favourable preconditions for its development. There are a lot of original research papers about a role of bacteria in caries decay but compositions and characters of oral microflora are changing nowadays. Therefore, authors show the main cariogenic bacteria and their factors of pathogenicity which create special conditions for caries lesions. Modern concepts of dental plaque formation and pathogenesis of plaque-assosiative diseases are presented according to the new actual dental research. A lot of attention is paid to the biochemical properties of cariogenic bacteria and chemical process in biofilm. Role of acid and alkali production by oral bacteria in caries decay are shown in this article. Moreover, mechanisms of bacterial acid-fast and acid-tolerance are presented.

CONCLUSION

Conclusions: Analysis of literature demonstrates a lot of bacterial pathogenicity factors which play key role in caries development.

Cariogenic Potential of the commonly Prescribed Pediatric Liquid Medicaments in Kingdom of Saudi Arabia: An in vitro Study

AIM

The aim of this study was to assess the cariogenic potential of the commonly prescribed pediatric liquid medicaments (PLMs) for dental disease in Jazan region, Kingdom of Saudi Arabia.

MATERIALS AND METHODS

Seven most commonly prescribed PLMs were selected by prior questioning the pediatric dentists as well as general dentists in Jazan region. The endogenous pH and sucrose concentrations of the liquid medicaments were assessed. The endogenous pH was assessed by Hanna pH meter instrument. The sucrose concentration was assessed by anthrone reagent method.

RESULTS

All the PLM were acidic. The pH of the PLM ranged from 4.22 to 6.10. All the PLM contained sucrose and its concentration ranged from 5.38 to 11.41 gm% in the samples.

CONCLUSION

In this study, all the PLM were acidic and contained sucrose. Hence, they have cariogenic potential.

CLINICAL SIGNIFICANCE

Parents and dentists are unaware of the hidden sugars and cariogenicity of these medications. Strict oral hygiene instructions are mandatory for the children taking these medications. The use of PLM should also be minimized and parents should seek early dental treatment to restore child's oral health.

In situ Effect of Frequent Sucrose Exposure on Enamel Demineralization and on Plaque Composition after APF Application and F Dentifrice Use

Since the effect of the combination of methods of fluoride use on enamel demineralization and on plaque composition is not clearly established, this study examined the effect of the combination of acidulated phosphate fluoride (APF) application and F dentifrice on enamel demineralization and on plaque composition. In this crossover study, 16 volunteers, wearing a palatal appliance containing bovine enamel blocks, were subjected to 4 treatment groups: non-fluoridated dentifrice (PD), FD, APF+PD, and APF+FD. The APF was applied to the enamel before the 14-day experimental period. During the experimental period, test dentifrices were applied 3×/day, and a 20% sucrose solution was applied 4× and 8×/day by being dripped on the blocks. Although APF application was able either to increase F concentration in plaque or to reduce the % of mutans streptococci, its combination with F dentifrice use neither reduced enamel mineral loss nor changed any other measured plaque variable with respect to the FD group alone.

Ca, Pi, and F in the Fluid of Biofilm Formed under Sucrose

Calcium (Ca), inorganic phosphorus (Pi), and fluoride (F) concentrations are low in the whole plaque biofilm formed under exposure to sucrose. It was hypothesized that this would be reflected in the biofilm fluid, where these low values should greatly influence the de/remineralization process. Dental biofilms were formed in situ over enamel blocks mounted in palatal appliances and exposed 8 times/day to distilled water, glucose+fructose, or sucrose solutions for 14 days. While Ca, Pi, and F concentrations in the whole biofilms were significantly lower in the glucose+fructose and sucrose groups, no effect on biofilm fluid was observed, even after a cariogenic challenge. An increase in whole biofilm mineral ions was observed 24 hrs after the carbohydrate treatments were suspended, but this effect was also not observed in the fluid. These results suggest that there is a homeostatic mechanism that maintains biofilm fluid mineral ion concentration, regardless of its total concentration in the whole biofilm.

Association between Type, Amount, and Pattern of Carbohydrate Consumption with Dental Caries in 12-Year-Olds in Puerto Rico

OBJECTIVE

To identify the types, food sources, and pattern of carbohydrates that significantly contribute to dental caries in Puerto Rican children.

METHODS

As part of an island-wide cross-sectional oral health study in 1,587 twelve-year-olds, diet intake was assessed in a representative subset (n = 801) with a 24-hour dietary recall. Carbohydrate intake was quantified using a computer-based diet analysis program. Caries was assessed using the National Institute of Dental and Craniofacial Research diagnostic criteria. Odds ratios were used to associate carbohydrate intake quartiles with caries, after controlling for important confounders.

RESULTS

A total of 723 subjects had complete data. Most were females (54%) and attended public schools (77%). The caries prevalence was 33%. The highest quartile intake for the following sugars significantly increased the odds of caries compared to the lowest quartile: total carbohydrates (OR = 1.93, 95% CI = 1.08-3.46), total sugars (OR = 1.88, 95% CI = 1.01-351), sucrose (OR = 2.05, 95% CI = 1.13-3.70), fructose (OR = 1.95, 95% CI = 1.05-3.62), and inositol (OR = 2.52, 95% CI = 1.38-4.63). The main food sources of these sugars were juices, including natural juices with no added sugars, and sweetened beverages. The odds of caries also increased significantly in children whose 10% of total energy intake was from total sugars (OR = 3.76, 95% CI = 1.03-13.7).

CONCLUSION

After adjusting for important caries risk factors, total carbohydrates, total sugars, ≥10% kilocaloric energy from total sugars, and sucrose, fructose, and inositol intake significantly increased caries risk. Our findings can help raise awareness about the potential caries risk from the main sources of these sugars, natural fruit juices and sweetened beverages, which are consumed in great quantities in many societies.

Influence of the number of adhesive layers on adhesive interface properties under cariogenic challenge using streptococcus mutans

PURPOSE

To test the hypothesis that the number of adhesive layers influences the adhesive interface properties under cariogenic challenge conditions using a Streptococcus mutans model.

MATERIALS AND METHODS

Bovine teeth (n = 90) were sectioned into blocks of 5 mm and divided into two groups for microleakage testing (n = 60) and tensile bond strength testing (n = 30). In each group, the samples were subdivided into subgroups according to the number of adhesive layers applied on the dentin: one (SB1), two (SB2), and three adhesive layers (SB3). The samples of the control groups were placed in BHI broth medium supplemented with 2% sucrose without microorganisms, and the experimental groups were submitted to Streptococcus mutans American Type Culture Collection (ATCC) for 5 days. For the tensile strength test, samples were sectioned into 1-mm-thick slices and submitted to a constant load of 0.5 mm/min in a universal testing machine. Fractured surfaces were analyzed and characterized as adhesive, cohesive, or mixed. The microleakage test was performed with silver nitrate solution.

RESULTS

In experimental groups, the tensile test revealed a statistically significant difference between the one- (18.59 ± 5.3) and three-layer (11.28 ± 5.0) groups (p < 0.001; ANOVA and Tukey's test). The adhesive failure mode was slightly more frequent in the one- (60%) and three-layer (80%) adhesive application groups. On the other hand, the microleakage levels of all experimental groups were statistically similar (Kruskal-Wallis; p > 0.05).

CONCLUSION

The experimental conditions influenced tensile properties and failure modes of different adhesive interfaces; however, they did not influence microleakage.

Parental views on delivering preventive advice to children referred for treatment of dental caries under general anaesthesia: a qualitative investigation

OBJECTIVES

To: 1, Explore opinions of parents of children undergoing caries treatment under general anaesthesia (GA) regarding delivery of oral health advice; 2, Discover current oral health practices and beliefs; 3, Inform further research and action.

METHODS

Qualitative study using semi-structured interviews and thematic data analysis, sampling parents of children aged 3-10 years undergoing GA tooth extraction due to dental caries.

RESULTS

Twenty nine parents were interviewed (mean age 38.9 years, range 28-50, sd 6.4). The mean age of their children was seven years (range 3-10, sd 2.1). All children required deciduous tooth extractions (5.1 teeth on average). Those that also required permanent tooth extractions had on average 2.1 permanent teeth extracted. Many parents knew the importance of oral hygiene and sugar limitation, describing it as 'general knowledge' and 'common sense'. However, few understood that fruit juice is potentially cariogenic. Parenting challenges seemed to restrict their ability to control the child's diet and establish oral hygiene. Many reported not previously receiving oral health advice and reported never having fluoride varnish applied. There were requests for more caries prevention information and advice via the internet, schools or video games.

CONCLUSION

Parental oral health knowledge, parenting skills, and previous advice received seem to all be issues related to the oral health of those children. Providing advice, especially in respect to fruit juice cariogenicity and the benefits of fluoride application through a child-friendly website, including a video game, as well as the use of school programmes might be an acceptable approach.

Role of fluoridated dentifrices in root caries formation in vitro

PURPOSE

To evaluate in vitro root caries formation in human permanent teeth and to determine the effects of commercially available dentifrices containing different amounts of fluoride, while employing a well-tested artificial caries system using an acidified gel.

METHODS

Root surfaces from caries-free human permanent teeth (n = 10) underwent debridement and fluoride-free prophylaxis. The tooth roots were sectioned into six portions, and acid-resistant varnish was placed with two sound root surface windows exposed on each tooth portion. Each portion from a single tooth was assigned to a treatment group: (1) No treatment control; (2) Denticious 5000 dentifrice (5,000 ppm F + xylitol); (3) PreviDent 5000 (5,000 ppm F); (4) AIM dentifrice (1,500 ppm F); (5) Listerine dentifrice (1,300 ppm F); and (6) Crest Regular Paste (1,500 ppm F). Tooth portions were treated with fresh dentifrice twice daily for 180 seconds, followed by fresh synthetic saliva rinsing over a 7-day period. Controls were exposed twice daily to fresh synthetic saliva rinsing over a 7-day period. In vitro root caries were created using an acidified gel (pH 4.25, 21 days). Longitudinal sections (three sections/tooth portion, 30 sections/group; 60 lesions/group) were evaluated for mean lesion depths (water imbibition, polarized light). Statistical analyses were performed using ANOVA and Duncan's Multiple Range test.

RESULTS

Mean lesion depths were 389 +/- 43 microm for No treatment - control, 223 +/- 33 microm for Denticious 5000 dentifrice, 242 +/- 42 microm for Prevident 5000, 337 +/- 29 microm for AIM dentifrice, 297 +/- 37 microm for Listerine dentifrice, and 282 +/- 34 microm for Crest Regular Paste dentifrice. All treatment groups had mean depths significantly less than the No treatment - control group (P < 0.05). Denticious 5000 and PreviDent 5000 had significantly reduced mean depth compared with the other dentifrice treatment groups (P < 0.05).

Staining of dentin from amalgam corrosion is induced by demineralization

PURPOSE

To evaluate the effect of artificial demineralization upon color change of dentin in contact with dental amalgam.

METHODS

Sound human molars (n = 34) were embedded in resin and coronal enamel was removed. Dentin was exposed to artificial caries gel (pH 5.5) at 37 degrees C for 12 weeks (n = 24). Non-demineralized teeth served as controls (n = the 10). A dispersive high-Cu amalgam or conventional low-Cu amalgam was condensed onto dentin surfaces of all groups. After 10 weeks storage in saline, amalgam was removed and teeth were cut into three slices. Surfaces were inspected under optical microscopy and photographed.

RESULTS

Penetration of black pigments was observed in dentin underneath both high-Cu and low-Cu amalgams in demineralized specimens. Black deposits were unevenly distributed and observed predominantly in dentin near to pulp horns. Discoloration was not limited to outer demineralized dentin but extended beyond this zone. Evenly distributed bluish-green discoloration was observed underneath all high-Cu amalgam specimens independent of demineralization.

Primary school-based behavioural interventions for preventing caries

BACKGROUND

Dental caries is one of the most common global childhood diseases and is, for the most part, entirely preventable. Good oral health is dependent on the establishment of the key behaviours of toothbrushing with fluoride toothpaste and controlling sugar snacking. Primary schools provide a potential setting in which these behavioural interventions can support children to develop independent and habitual healthy behaviours.

OBJECTIVES

To assess the clinical effects of school-based interventions aimed at changing behaviour related to toothbrushing habits and the frequency of consumption of cariogenic food and drink in children (4 to 12 year olds) for caries prevention.

SEARCH METHODS

We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 18 October 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 4), MEDLINE via OVID (1948 to 18 October 2012), EMBASE via OVID (1980 to 18 October 2012), CINAHL via EBSCO (1981 to 18 October 2012) and PsycINFO via OVID (1950 to 18 October 2012). Ongoing trials were searched for using Current Controlled Trials (to 18 October 2012) and ClinicalTrials.gov (to 18 October 2012). Conference proceedings were searched for using ZETOC (1993 to 18 October 2012) and Web of Science (1990 to 18 October 2012). We searched for thesis abstracts using the Proquest Dissertations and Theses database (1950 to 18 October 2012). There were no restrictions regarding language or date of publication. Non-English language papers were included and translated in full by native speakers.

SELECTION CRITERIA

Randomised controlled trials of behavioural interventions in primary schools (children aged 4 to 12 years at baseline) were selected. Included studies had to include behavioural interventions addressing both toothbrushing and consumption of cariogenic foods or drinks and have a primary school as a focus for delivery of the intervention.

DATA COLLECTION AND ANALYSIS

Two pairs of review authors independently extracted data related to methods, participants, intervention design including behaviour change techniques (BCTs) utilised, outcome measures and risk of bias. Relevant statistical information was assessed by a statistician subsequently. All included studies contact authors were emailed for copies of intervention materials. Additionally, three attempts were made to contact study authors to clarify missing information.

MAIN RESULTS

We included four studies involving 2302 children. One study was at unclear risk of bias and three were at high risk of bias. Included studies reported heterogeneity in both the intervention design and outcome measures used; this made statistical comparison difficult. Additionally this review is limited by poor reporting of intervention procedure and design. Several BCTs were identified in the trials: these included information around the consequences of twice daily brushing and controlling sugar snacking; information on consequences of adverse behaviour and instruction and demonstration regarding skill development of relevant oral health behaviours.Only one included study reported the primary outcome of development of caries. This small study at unclear risk of bias showed a prevented fraction of 0.65 (95% confidence interval (CI) 0.12 to 1.18) in the intervention group. However, as this is based on a single study, this finding should be interpreted with caution.Although no meta-analysis was performed with respect to plaque outcomes (due to differences in plaque reporting between studies), the three studies which reported plaque outcomes all found a statistically significant reduction in plaque in the intervention groups with respect to plaque outcomes. Two of these trials involved an 'active' home component where parents were given tasks relating to the school oral health programme (games and homework) to complete with their children. Secondary outcome measures from one study reported that the intervention had a positive impact upon children's oral health knowledge.

AUTHORS' CONCLUSIONS

Currently, there is insufficient evidence for the efficacy of primary school-based behavioural interventions for reducing caries. There is limited evidence for the effectiveness of these interventions on plaque outcomes and on children's oral health knowledge acquisition. None of the included interventions were reported as being based on or derived from behavioural theory. There is a need for further high quality research to utilise theory in the design and evaluation of interventions for changing oral health related behaviours in children and their parents.

Cariogenic potential of commercial sweeteners in an experimental biofilm caries model on enamel

OBJECTIVE

Scarce evidence is available on the cariogenic potential of the widely used commercial sweeteners. The aim of this study was to evaluate the effect of several sweeteners on enamel demineralisation and on the cariogenic properties of Streptococcus mutans biofilms in an artificial caries model.

METHODS

S. mutans-UA159 biofilms were cultured on bovine enamel slabs and exposed to one of the following commercial sweeteners in tablet or powder form: stevia, sucralose, saccharin, aspartame or fructose. Ten percent sucrose and 0.9% NaCl were used as caries-positive and caries-negative controls, respectively. Slabs/biofilms were exposed to the sweeteners three times per day for 5min each time. After 5 days, biofilms were recovered to determine: biomass, bacterial counts and intra- and extracellular polysaccharides. Surface microhardness was measured before and after the experiment to assess enamel demineralisation, expressed as percentage of surface hardness loss (%SHL). Data were analysed using analysis of variance (ANOVA) and Bonferroni (p<0.05).

RESULTS

All tested commercial sweeteners, except fructose, showed less enamel demineralisation than sucrose (p<0.05). Only saccharine showed less biomass and intracellular polysaccharides than the rest of the groups (p<0.05). Stevia, sucralose and saccharine reduced the number of viable cells when compared with sucrose (p<0.05). All sugar alternatives reduced extracellular polysaccharide formation when compared with sucrose (p<0.05).

CONCLUSIONS

Most commercial sweeteners appear to be less cariogenic than sucrose, but still retaining some enamel demineralisation potential. Products containing stevia, sucralose and saccharine showed antibacterial properties and seem to interfere with bacterial metabolism. Further studies are necessary to deepen these findings.

Effect of bovine milk on Streptococcus mutans biofilm cariogenic properties and enamel and dentin demineralization

PURPOSE

The purpose of this study was to evaluate the effect of whole bovine milk on Streptococcus mutans biofilms and on demineralization of enamel and root dentin.

METHODS

S mutans UA159 biofilms were cultured on enamel and dentin bovine slabs of known surface hardness (SH) and exposed (8x/day) to 10% sucrose (positive control), whole bovine milk, and 4.5% lactose. Biofilm acidogenicity was estimated by medium pH (2x/day). After 4 days for dentin and 5 days for enamel, biofilms were collected to obtain biomass, viable bacteria, total protein, and intra- and extracellular polysaccharides. Final SH was measured on the slabs. Demineralization was calculated as percentage of SH loss (%SHL). Differences were determined by analysis of variance and Tukey's test (P<.05).

RESULTS

Biofilms formed on both substrates under 10% sucrose showed higher acidogenicity, biomass, protein concentration, insoluble polysaccharides, and %SHL than those treated with milk or lactose (P<.05), which did not differ in any parameter (P>.05). Higher bacterial counts were obtained from biofilms treated with milk on enamel, but not on dentin. Dentin was significantly more demineralized by milk than enamel (P<.05).

CONCLUSIONS

Although bovine milk appears to be less cariogenic than sucrose, this dairy product should not be considered caries-safe.

A comparison of sports and energy drinks--Physiochemical properties and enamel dissolution

The consumption of sports and energy drinks by children and adolescents has increased at an alarming rate in recent years. It is essential for dental professionals to be informed about the physiochemical properties of these drinks and their effects on enamel. The present study measured the fluoride levels, pH, and titratable acidity of multiple popular, commercially available brands of sports and energy drinks. Enamel dissolution was measured as weight loss using an in vitro multiple exposure model consisting of repeated short exposures to these drinks, alternating with exposure to artificial saliva. The relationship between enamel dissolution and fluoride levels, pH, and titratable acidity was also examined. There was a statistically significant difference between the fluoride levels (p = 0.034) and pH (p = 0.04) of the sports and energy drinks studied. The titratable acidity of energy drinks (11.78) was found to be significantly higher than that of sports drinks (3.58) (p < 0.001). Five of the energy drinks (Red Bull Sugar Free, Monster Assault, Von Dutch, Rockstar, and 5-Hour Energy) were found to have the highest titratable acidity values among the brands studied. Enamel weight loss after exposure to energy drinks was significantly higher than it was after exposure to sports drinks. The effect of titratable acidity on enamel weight loss was found to vary inversely with the pH of the drinks. The findings indicated that energy drinks have significantly higher titratable acidity and enamel dissolution associated with them than sports drinks. Enamel weight loss after exposure to energy drinks was more than two times higher than it was after exposure to sports drinks. Titratable acidity is a significant predictor of enamel dissolution, and its effect on enamel weight loss varies inversely with the pH of the drink. The data from the current study can be used to educate patients about the differences between sports and energy drinks and the effects of these drinks on tooth enamel.

Dietary considerations for patients with dry mouth

Dental caries is seen frequently in patients diagnosed with dry mouth. Nutritional counseling is important for the effective management of dry mouth and to arrest dental caries. With early intervention and proper individualized care, patients with dry mouth should be able to lead full, comfortable lives.

Fluoride plus CO2 laser against the progression of caries in root dentin

PURPOSE

To evaluate the effect of a 1.23% acidulated phosphate fluoride (APF) gel combined with CO2 laser in protecting carious root dentin against further cariogenic challenges.

METHODS

After a 7-day lead-in period, 12 volunteers wore an intraoral palatal device containing four carious root dentin slabs, treated with APF and APF+CO2 or placebo and placebo+CO2. After a 14-day wash-out period, volunteers were crossed-over to the other treatment arm. During both intraoral phases, specimens were submitted to cariogenic challenges and then evaluated for cross-sectional Knoop microhardness.

RESULTS

Two-way ANOVA demonstrated that there was significant effect for both main factors: CO2 laser irradiation (P < 0.0001) and gel treatment (P < 0.0001), and that there was no interaction between them (P = 0.4706). Protection of carious root dentin against further cariogenic challenges may be provided by APF fluoride gel and CO2 laser, but no additive benefit was found by combining such strategies.

In vitro analysis of the cariogenic and erosive potential of paediatric antitussive liquid oral medications

We evaluated in vitro the cariogenic and erosive potential of antitussive liquid oral medications for paediatric use. Fifteen paediatric liquid antitussives were sampled. The endogenous pH was evaluated by potentiometry, titratable acidity was measured according to the method adopted by the Association of Official Analytical Chemists, total soluble solids content (TSSC) readings were performed by Brix refractometry using the Abbé refractometer, and the total sugar content was determined according to the Fehling methodology. The experiments were performed in triplicate and the obtained data were entered in the Excel software, analyzed and presented by descriptive statistics (means and standard deviations). Endogenous pH values ranged from 2.49 ± 0.09 (Iodetox®) to 6.75 ± 0.005 (Carbocysteine®) and twelve medications showed pHs below the critical value of 5.5 for enamel demineralization. Iodetox® (0.021 ± 0.01) presented the lowest titratable acidity and Aerofrin® (1.171 ± 0.01) presented the highest titratable acidity. Celergin® presented the highest TSSC (62.26 ± 0.40) and Acetyleysteine® (100 mg granules bags) presented the lowest TSSC (3.25 ± 0.43). Only 5 medications contained sugar, with total sugar content ranging from 35.93% ± 6.65 (Iodetox®) to 59.60% DP ± 6.66 (Celergin®). The paediatric antitussive medications showed low endogenous pH, some of them even below the critical value for enamel dissolution (pH<5.5). These antitussives are potentially cariogenic and erosive to dental structures if used frequently because of the high titratable acidity and high sugar concentration, especially when adequate oral clearance is not performed after administration of each dose.

Effect of bamboo salt-NaF dentifrice on enamel remineralization

PURPOSE

To evaluate the laboratory remineralization effects of a dentifrice with bamboo salt and NaF on artificial caries-like enamel lesions, at both the surface and deep areas.

METHODS

Early dental caries lesions were formed by treating bovine enamel samples for 48 hours at 37 degrees C with a demineralization solution (pH 5.0) containing 0.1 M lactic acid, 0.2% Carbopol 907, and 50% saturated calcium phosphate tribasic. pH cycling was then performed by immersing the samples in dentifrice slurry for 2 minutes every 8 hours per day, and in demineralization solution for 4 hours and mixed saliva for the remaining time period. The mixed saliva consisted of 50% human saliva and 50% artificial saliva. The surface hardness and the level of mineral surface alterations were analyzed using a hardness tester and transversal microradiography, among negative control (fluoride free), positive control (sodium fluoride 1100 ppm, Crest Cavity Protection), and test dentifrice (3.0% bamboo salt with sodium fluoride 1,000 ppm) groups.

RESULTS

Test and positive control groups significantly increased the level of the surface hardness and decreased mineral loss of the artificial caries-like enamel lesions compared to the negative control (P<0.05). The test dentifrice also significantly decreased the lesion depth compared to the other two groups (P<0.05).

Traditional and emerging oral health practices in parts of Nigeria

OBJECTIVE

The purpose of this study was to document the beliefs and perceptions and emerging oral health care practices in parts of Nigeria.

METHODS

A descriptive study, based in four different locations that were selected to reflect urban-rural and geographical spread, was conducted. Focus group discussions and in-depth interviews were conducted among representative groups and significant gatekeepers in the study areas. The discussions focused on oral health problems frequently encountered in the communities, their dietary and snacking habits as well as the dental remedies commonly employed by the people for prophylactic and therapeutic purposes.

RESULTS

It was revealed that in both rural and urban low- to- middle socio-economic classes, periodontitis was the commonest dental problem in adults, while dental caries in children appeared to be also a cause for concern especially in northern Nigeria and the urban south. Most adults ate the local staple carbohydrate diets, however large quantities of cariogenic snacks were reported to be consumed. Chewing sticks and locally prepared toothpastes ranked prominent among the tooth cleaning implements, but many in the cities used toothbrushes. Various dental care remedies were employed ranging from warm saline wash to herbal preparations, antibiotics and battery water. In communities studied, the belief in ill defined "worms" as causative agents of all oral health problems was very firm. Consultation with traditional oral healthcare practitioners was a practice commonly observed in all study sites.

CONCLUSION

This study has highlighted specific areas for intervention in disease prevention and oral health promotion in Nigeria.

Effect of a fluoride- and bromide-containing adhesive system on enamel around composite restorations under high cariogenic challenge in situ

PURPOSE

To evaluate the effect of a novel antibacterial and fluoride-releasing adhesive formulation on enamel demineralization under sucrose exposure in situ (simulating high caries risk conditions).

MATERIALS AND METHODS

This crossover, blind study was performed in two phases of 14 days. Volunteers (n = 14) wore an intraoral appliance containing four bovine enamel blocks with cavity preparations restored using self-etching primers/composite resin (Clearfil SE Bond or Clearfil Protect Bond/Clearfil AP-X). The volunteers dropped 20% sucrose solution 8x/day and used fluoridated dentifrice 3x/day. After 14 days, enamel mineral loss was assessed by cross-sectional microhardness (CSMH), and the demineralization areas in enamel adjacent to the restoration were examined by scanning electron microscopy (SEM) and polarizing light microscopy (PLM). The CSMH data were analyzed using ANOVA and Tukey's test (p < 0.05).

RESULTS

Enamel blocks restored with Clearfil Protect Bond showed higher mineral content (%vol) adjacent to restorations than Clearfil SE Bond only for the first site of microhardness measurement and close to enamel surface (20 microm). SEM and PLM analysis suggested that the Clearfil Protect Bond adhesive promoted less enamel demineralization around restorations.

CONCLUSION

After 14 days of cariogenic challenge, the findings suggested that Clearfil Protect Bond might help to control the demineralization around restorations in cases of high caries risk.

Effect of calcium pre-rinse and fluoride dentifrice on enamel and on dental plaque formed in situ

PURPOSE

The aim of this in situ double-blind randomised crossover study was to investigate the effect of calcium (Ca) pre-rinse on the composition of plaque and on enamel prior to the use of fluoride (F) dentifrice.

MATERIALS AND METHODS

During four phases (14 days each) of this study, 10 volunteers had agreed to wear dental appliances containing two healthy bovine enamel blocks. A fresh solution containing 20% weight/volume (w/v) sucrose was dripped on the enamel blocks ex vivo for 5 min three times a day. Subsequently, the appliances were replaced in the mouth, and the volunteers rinsed their mouth with 10 mL of a Ca (150 mmol/L) or a placebo rinse (1 min). In sequence, a slurry (1:3 w/v) of F (1030 ppm) or placebo dentifrice was dripped onto the blocks ex vivo for 1 min. During this time, the volunteers brushed their teeth with the respective dentifrice. The appliances were replaced in the mouth, and the volunteers rinsed their mouth with water. The plaque formed on the blocks was analysed for F and Ca. The enamel demineralisation as well as the incorporation of F on enamel was evaluated by cross-sectional microhardness and alkali-soluble F analysis, respectively. Data were tested using analysis of variance (P < 0.05).

RESULTS

The Ca pre-rinse prior to the use of the F dentifrice led to a three- and sixfold increase in the plaque F and Ca concentrations, respectively. It also did not have any additive effect on the F content on the enamel and the demineralisation of the enamel, in comparison with the use of F dentifrice alone.

CONCLUSIONS

A Ca lactate rinse used prior to the F dentifrice was able to change the mineral content in the plaque, but it was unable to prevent enamel demineralisation.

Cariogenic and erosive potential of the medication used by HIV-infected children: pH and sugar concentration

OBJECTIVE

The aim of this work was to analyze pH and sugar concentration in seven antiretroviral and three antibacterial medications frequently prescribed to HIV infected paediatric patients.

METHOD

Sugars (sucrose, glucose, lactose and fructose) and pH were measured from every one of ten medications with different serial numbers in two samples. The pH was determined by a previously calibrated digital pHmeter (Beckman). Analysis of free sugars was performed using thin-layer chromatography (TLC). The pH results and the amount of sugar originated from the two samples in each lot were added. The arithmetic mean of these results were computed.

RESULTS

Two antiretrovirals (Zidovudin and Abacavir Sulphate) had pH below critical level (3.55 and 3.93, respectively). All three antibacterials analyzed had pH above 5.5, and one of them (Azithromycin) had the highest pH level of the ten medications examined (9.28). Sugar was present in seven out of 10 of the medications analyzed. The antibacterials contained the highest concentration of sucrose, ranging from 40% to 54%. Glucose was found in one of the ten, sucrose was present in seven of them and none showed lactose. Fructose was not observed with the technique used.

CONCLUSIONS

A number of medications frequently used by HIV-infected children may cause a significant risk of both caries and dental erosion.

Fluorescence changes in remineralized and nonremineralized enamel adjacent to glass ionomer ART restorations: an in vitro study

PURPOSE

The purpose of this study was to evaluate fluorescence changes of remineralized and nonremineralized enamel margins adjacent to glass ionomer restorations during a pH cycling sequence.

METHODS

One hundred permanent molar and premolar teeth were placed in a demineralizing solution for 3 days and restored with a glass ionomer restoration (simulating Atraumatic Restorative Treatment [ART]). Half were placed in a remin solution for 7 days to create a remineralization (remin) group. Specimens were randomly divided into 4 groups (N=25): (a) 2 remin groups; and (b) 2 nonremin groups. One half of the remin and nonremin group specimens were treated with a 5,000-ppm sodium fluoride solution during pH cycling with remin fluid and an acidic beverage over 20 days. Fluorescence changes were recorded with quantitative light fluorescence (QLF). Higher fluorescence values indicated less lesion porosity. Statistical comparisons between the groups over the 5 measurement sessions of cycling were performed using repeated measures of analysis of variance with a post-hoc test, paired-sample t test and 2-sample t tests (alpha=0.05).

RESULTS

The remin groups experienced significantly less lesion porosity than the nonremin groups. Fluoride groups experienced less lesion porosity than the nonfluoride groups.

CONCLUSIONS

A brief period of remineralization and use of a prescription strength fluoridated rinse improved the enamel substrate surrounding glass ionomer restorations, resulting in less lesion porosity.

A comparison of terahertz pulsed imaging with transmission microradiography for depth measurement of enamel demineralisation in vitro

Terahertz pulsed imaging (TPI) is a relatively new, non-ionising and non-destructive imaging technique for studying hard tissues which does not require tooth section preparation, unlike transmission microradiography (TMR). If TPI can measure the depths of caries/demineralisation lesions accurately the same tooth samples could be reused and remeasured during in vitro and in situ studies on de- and/or re-mineralisation. The aim of this study was to compare TPI and TMR for measuring the depths of a range of artificially induced bovine enamel demineralised lesions in vitro. Bovine slabs with artificial caries, induced to different levels of demineralisation by two different but standard demineralisation techniques ('acid gel' and 'carbopol') were measured by TPI and TMR and the readings compared. The set of TPI/TMR measurements obtained on the gel-demineralised slabs showed an extremely high coefficient of determination (r(2) = 0.995). Detailed analysis of the results and theoretical considerations (involving the relationship between refractive index profiling and mineral loss profile) are used to explain the findings and show that for acid gel lesions TPI is measuring demineralisation in the range of 47% of that of TMR depth plus an intercept of 16 microm, with further calculations allowing the TMR depths to be determined to within 5% using TPI.

The role of sucrose in cariogenic dental biofilm formation--new insight

Dental caries is a biofilm-dependent oral disease, and fermentable dietary carbohydrates are the key environmental factors involved in its initiation and development. However, among the carbohydrates, sucrose is considered the most cariogenic, because, in addition to being fermented by oral bacteria, it is a substrate for the synthesis of extracellular (EPS) and intracellular (IPS) polysaccharides. Therefore, while the low pH environment triggers the shift of the resident plaque microflora to a more cariogenic one, EPS promote changes in the composition of the biofilms' matrix. Furthermore, it has recently been shown that the biofilm formed in the presence of sucrose presents low concentrations of Ca, P(i), and F, which are critical ions involved in de- and remineralization of enamel and dentin in the oral environment. Thus, the aim of this review is to explore the broad role of sucrose in the cariogenicity of biofilms, and to present a new insight into its influence on the pathogenesis of dental caries.

[Dentin demineralization in situ during frequent exposures to bananas or sucrose]

The aim of the study was to compare sucrose solution and bananas on demineralizing potential in situ, and to address the question if fluoride toothpaste is equally effective in preventing dentin demineralization at open, smooth surfaces and at plaque stagnation sites (grooves). Four volunteers wore an appliance containing bovine dentin specimens with narrow grooves and a smooth surface for two 1-week in situ periods, with 8 1-minute exposures daily: either by a rinse with 10% sucrose, or by consumption of a piece of banana. Twice daily, the appliance was dipped in toothpaste slurry of a fluoride-free toothpaste at one side and a fluoride toothpaste at the contralateral side. Demineralization was assessed by tranversal microradiography. No difference in dentin demineralization was found after frequent exposure to either sucrose solution or bananas. Fluoride toothpaste effectively protected dentin only at the smooth surfaces. In the grooves, fluoride affected the demineralization pattern; it drove lesions towards the bottom of the groove.

Food labeling: health claims; dietary noncariogenic carbohydrate sweeteners and dental caries. Final rule

The Food and Drug Administration (FDA) is announcing its decision to authorize the use of a health claim regarding the association between sucralose and the nonpromotion of dental caries. Based on its review of evidence described in the proposed rule and comments submitted on the proposed rule, the agency has concluded that sucralose does not promote dental caries. Therefore, the agency has decided to amend the regulation that authorizes a health claim regarding noncariogenic carbohydrate sweeteners to include sucralose.

Dietary intakes and caries experience in children in Limpopo Province, South Africa

INTRODUCTION

The identification of a rural village with a very low incidence of dental caries among the children provided the opportunity to study the diets of children apparently not exposed to risk factors for dental caries and compare them with children who were at risk.

OBJECTIVE

To compare the diet, nutritional status and dental caries experience of 10- and 15-year-olds in an urban town (Malamulele) and a rural village (Mahonisi) in the Limpopo Province, South Africa.

METHODS

Dental examinations and anthropometric measurements were done according to standard procedures. Dietary intakes were assessed by four 24-hour recalls.

RESULTS

Mean dft/DMFT (decayed and filled deciduous teeth/Decayed, missing and filled permanent teeth) scores were 1.21 and 0.65 for 10- and 15-year-olds in urban Malamulele compared to 0.33 and 0.02 in rural Mahonisi. The percentage caries free in Malamulele was 36% compared to 88% in Mahonisi. The children in Mahonisi were shorter and lighter than those in Malamulele. Estimated fluoride intakes were significantly lower in Malamulele than in Mahonisi (p = 0.01). Mean total added sugar (all sugar not naturally occurring in foods) intake in Malamulele was significantly higher than in Mahonisi (p < 0.05).

CONCLUSION

The most significant dietary differences between the two areas were total added sugar and fluoride intakes. The lower added sugar and higher fluoride intake among the rural Mahonisi children contributed to the lower dental caries experience.

Soft drinks and dental health: a review of the current literature

In recent years there has been increased interest in the role of commercial soft drinks in dental diseases namely as dental caries and erosion. The objective of this paper has been to review the past and current literature to determine the present knowledge on this subject. The literature related to dental caries, erosion, drinks, soft drinks and fruit juices was reviewed. The literature shows efforts have been taken to modify soft drinks by either adding or deleting certain components so as to reduce their harmful effects on teeth. A rational protocol to encourage the sensible use of drinks and the modification of drinks to render them less harmful would be advisable.

A Novel in vitro Microbial-Based Model for Studying Caries Formation – Development and Initial Testing

We report on the development and the initial testing of a new microbial-based caries model. Specimens were fixed on a rotating mount within a reaction chamber hermetically surrounded by a sterilised glove box. A cariogenic environment was obtained by inoculation with Streptococcus mutans (ATCC 25175) combined with a continuously repeating supply of sucrose solution, trypticase soy broth and artificial saliva applied by dripping. Twenty-five caries-free upper premolars were used. The mesial parts of the occlusal fissures had been sealed with a resin-based fissure sealant (test group 1). To produce marginal gaps, the distal parts had been moistened with saliva before resin application (test group 2). Five teeth served as control and were exposed to all fluids under sterile conditions before being removed from the system after 7 days. Test specimens were infected with S. mutans and were incubated for another 14 days. No unintentional contamination occurred during the 3-week period of operation. Demineralizations were evaluated by using confocal laser scanning microscopy. Only the test specimens showed clearly visible signs of biofilm formation and caries-like lesions. The mean primary lesion depth did not differ significantly between test groups. Wall lesion depths and surface areas of demineralizations underneath the fissure sealants were significantly higher in test group 2. Thus, our model allows the simultaneous production of primary and secondary caries-like enamel lesions in a considerable number of specimens and facilitates the possibility to manipulate and transfer them without necessarily terminating the experiment, opening new possibilities for in vitro caries research.

Efficacy of fluoride toothpaste in preventing demineralization of smooth dentin surfaces and narrow grooves in situ under frequent exposures to sucrose or bananas

The use of models simulating fissures allows studying demineralization at sites that are most prone to caries in vivo. In practice, most in situ models use flat surfaces. Our objectives were: (1) to compare the demineralizing potential of sucrose solution with that of bananas and (2) to study the effect of fluoride toothpaste on demineralization in situ in an easily accessible site and a plaque stagnation site. Four volunteers wore bovine dentin specimens with narrow grooves and a smooth surface for two 1-week in situ periods, with eight 1-min sugar exposures daily: either by a rinse with 10% sucrose, or by consumption of a piece of banana. Twice daily, the appliance was dipped in toothpaste slurry of a control (fluoride-free) toothpaste at one side and a fluoride toothpaste at the contralateral side. Demineralization was assessed by transversal microradiography. We found no difference in dentin demineralization after frequent exposure to either sucrose solution or bananas. Fluoride toothpaste effectively protected dentin only at the smooth surface. In the grooves, fluoride affected the demineralization pattern; it drove lesions towards the bottom of the groove. We conclude that assessing only smooth surfaces in intraoral tests might lead to underestimated food cariogenicity and to overestimated efficacy of fluoride-containing toothpaste.

Effect of Sucrose Containing Iron (II) on Dental Biofilm and Enamel Demineralization in situ

Since the effect of iron (Fe) on the cariogenicity of sucrose in humans is unexplored, this study assessed in situ the effect of Fe co-crystallized with sucrose (Fe-sucrose) topically applied in vitro on the acidogenicity, biochemical and microbiological composition of the dental biofilm formed in vivo and on the demineralization of the enamel. During two phases of 14 days each, 16 volunteers wore palatal appliances containing blocks of human enamel, which were submitted to four groups of separate treatments: (1) water; (2) 20% sucrose; (3) 20% (w/v) sucrose plus 18 microg Fe/ml, and (4) 20% (w/v) sucrose plus 70 microg Fe/ml. The solutions were dripped onto the blocks 8 times per day. The biofilms formed on the blocks were analyzed with respect to acidogenicity, biochemical and microbiological composition. Mineral loss was determined on enamel by surface and cross-sectional microhardness. Lower demineralization was found in the blocks subjected to Fe-sucrose (70 microg Fe/ml) than in those treated with sucrose (p < 0.05). This concentration of Fe also reduced significantly the populations of mutans streptococci in the biofilm formed on the blocks. In conclusion, our data suggest that Fe may reduce in situ the cariogenic potential of sucrose and the effect seems to be related to the reduction in the populations of mutans streptococci in the dental biofilm formed.

Medications' impact on oral health

BACKGROUND

Over-the-counter and prescription drugs are used frequently, in large quantities and by many adults, particularly by those older than 65 years of age. A number of medications (prescription, over-the-counter, vitamins and minerals, herbal preparations) can affect oral health. With the population's aging, and as more drugs become available, dentists can expect to encounter medication-related oral side effects among their patients.

TYPES OF STUDIES REVIEWED

The author reviewed studies that ranged from case reports to randomly controlled, double-blinded studies. However, in view of the subject matter, the majority of findings are based on case reports.

CONCLUSIONS

Since many patients regularly take medications, both prescribed and nonprescribed, dentists always must take a thorough medical history so that they can be aware of medication-related problems and the impact of medications on diagnosis and treatment planning.

CLINICAL IMPLICATIONS

Dentists must be aware of the potential oral tissue complications that medications can create and develop appropriate treatment plans for their patients that consider the oral health impact of the medications they take.

The effect of fluorine and homeopathic medicines in rats fed cariogenic diet

Although some sectors of dentistry have benefited from technological advances, dental caries is still a major problem. Prevention and treatment of dental caries by fluorine is considered a major advance in public health. Nevertheless fluorosis, caused by ingestion of excessive amounts of fluorine during the period of teeth formation, is of great concern. In accordance with the homeopathic doctrine, minimum doses of fluorine and other substances could prevent and/or treat caries. In this experiment, we compared the preventive action of fluorine and evaluated the effect of homeopathic medicines on the teeth of rats fed a cariogenic diet. None of the groups included in this study developed caries. However, microscopy revealed the presence of precipitate and/or deposit in the groups treated with homeopathic medicines. This phenomenon might be due to deposit in the dental surface or precipitation of bacterial plaque or calcium salts. It was not possible to identify the composition of the deposit/precipitate due for technical reasons. In one of the groups treated with homeopathic medicines fur loss was observed in 40% of animals. These reactions might be caused due to the action of the homeopathic medicines.

A review of fluorosis in the European Union: prevalence, risk factors and aesthetic issues

Fluoride has played a key role in caries prevention for the past 50 years but excessive ingestion of fluoride during tooth development may lead to dental fluorosis. Throughout Europe many vehicles have been, and are currently, employed for optimal fluoride delivery including drinking water, toothpaste, fluoride supplements, salt and milk. Several indices, both descriptive and aetiological, have been developed and used for measuring fluorosis. This factor, combined with the lack of use of a standardized method for measurement of fluorosis, has made comparison between studies difficult and assessment of trends in fluorosis prevalence unreliable. Overall the evidence would appear to indicate, however, that diffuse enamel opacities are more prevalent in fluoridated than in nonfluoridated communities and that their prevalence at the very mild level may be increasing. In addition to fluoridated drinking water, risk factors for fluorosis include inadvertent ingestion of fluoride toothpaste and the inappropriate use of fluoride supplements. The risk is of aesthetic concern primarily during the period of enamel development of the permanent central incisors, although this largely appears to be a cosmetic rather than a public-health issue. It is concluded that there is a need to co-ordinate studies measuring fluorosis throughout Europe and that development of a standardized photographic method would be useful. Furthermore, the aesthetic importance of fluorosis needs to be determined in more detail in each country in the light of each country's respective risk factors and dental health policies.

The effect of a single application of 40% chlorhexidine varnish on the numbers of salivary mutans streptococci and acidogenicity of dental plaque

The relationship between the numbers of salivary mutans streptococci and the acid production in dental plaque after a single application of the 40% chlorhexidine varnish EC40 has been studied. Thirteen healthy subjects were treated with EC40 varnish. Saliva samples were taken before and up to 12 weeks after treatment to count mutans streptococci and lactobacilli. At the same time points plaque samples were taken before and after sucrose challenge and analyzed for protein and organic acid. Suppression of salivary mutans streptococci was observed together with a reduced production of lactic acid in sucrose-challenged dental plaque in 9 subjects while inhibition of acid production without significant suppression of mutans streptococci was observed in the other 4 participants. The duration of the effects differed among the individuals but never exceeded 6 weeks. We conclude that a prolonged suppression of mutans streptococci and acid production was not achieved by a single treatment with EC40 varnish in all subjects. Moreover, reduced acidogenicity of dental plaque after chlorhexidine treatment was not necessarily predicted by suppression of mutans streptococci in saliva.

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

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 (DeltaZ) 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 DeltaZ 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 DeltaZ 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.

Resistance of marginal enamel to acid solubility is influenced by restorative systems: an in vitro scanning electron microscopic study

The aim of this study was to evaluate the morphology of the enamel surface along margins of class V restorations following exposure to cariogenic solution. Restorations were placed in vitro in human third molars. The specimens were divided into groups according to resin composition: (1) Scotchbond 1 + Filtek Flow, (2) Scotchbond 1 + F2000, and (3) Prompt L-Pop + experimental flowable composite. Samples were stored in a demineralizing solution (lactic acid, pH 4.5, 0.1 M) at 37 degrees for 1-4 weeks or in deionized water (control group). The solution was changed every day. Replicas of the specimens were obtained in order to exclude drying artifacts. Scanning electron microscopy (SEM) of original and replica specimens identified a distinct enamel zone, defined as perimarginal enamel showing numerous fractures, porosities, voids, and pits. After the 4-week treatment, perimarginal prismatic enamel was greatly removed, while interprismatic enamel was still in place and only partially dissolved. Enamel not in relation with composite/compomer margins (0.5-1 mm away) showed minor alterations. Perimarginal enamel fractures probably due to composite/compomer shrinkage or the bur preparation may greatly contribute to this marginal enamel demineralization by increasing the number and size of porosities, that enhance the penetration and diffusion of cariogenic solution and create a sort of demineralized enamel subsurface. Only compomer restorations revealed a thin caries inhibition zone (1-2 micro m) probably related to fluoride release. Below this protected area, we observed the typical alterations of the other samples. These morphological alterations are probably related to secondary demineralization lesions and may affect the clinical life of restorations.

[The use of fluorides in dentistry in the year 2003]

During the 20th century the entire Western world has been plagued by a tremendous increase of carious lesions in the dentition of children and adults. Near the end of that century a definite decrease in the number of carious lesions was noticed. That improvement in dental health is mainly attributed to an increased presence of fluorides in the oral cavity. Fluorides can be administrated systemically or locally. Recent findings clearly suggest that a local administration is the preferred option. Correctly applicated the local use of fluorides provides a favourable and positive effect during demineralization and remineralisation processes under carious attack. Although fluorides are not the only measure in caries prevention it is widely believed that they have largely contributed to an improvement of oral health, the relief of dental pain and the safeguarding of financial means during the last twenty five years.

A comparison of oral hygiene status and dental caries in children on long term liquid oral medications to those not administered with such medications

Young chronically ill children receive a greater sugar load from liquid medications than do healthy children. They receive variety of oral liquid medications that healthy children do not This study was planned to know the levels of oral hygiene and Dental caries in children on long term liquid oral medicines (LOM) and to know out if any difference existed between these and children not on LOM. 51 children on LOM were compared to 54 not on LOM after equalising for age, oral hygiene and diet intake. Highly significant difference was found for dmft and dmfs in 2-6 year age group and dmft+ DMFT for 6-13 years age group, mostly posterior teeth were affected and for this the difference was statistically significant in 2-6 year old children. Percentage of children with dmft>5 significantly increased in 2-6 years old children on LOM, when compared to that of control. Percentage of various grades of lesions (relating to the severity) also increased with an increase in the duration of LOM.

"Cariogenic potential of homemade weaning diet v/s commercial formula feeds" an in-vitro study

The universal phenomenon of introducing weaning diet to the growing child sets its onset by the age of 4-6 months. This preliminary diet of the child governs his or her dental health in the long run. The main objective of this study is to investigate the histopathological and clinical invasion of deciduous teeth exposed to both the homemade weaning diet and commercial formula feeds. The study also aims at motivating the consumption of the most appropriate diet for the weaning baby. Extracted deciduous teeth were incubated with the test solutions of homemade diet and commercial formula feeds for the period of 6 weeks. Fewer carious invasion both clinically and histopathologically were seen in homemade feeds. Thus, homemade diet can be a strong candidate for the status of 'THE IDEAL WEANING FOOD'.

Evaluation of the cariogenic potential of cassava flours from the Amazonian region

Cassava flour is the main dietary carbohydrate source in the Amazonian region. The cariogenic potentials of the two main kinds of cassava flour - 'seca' and 'd'água' - were evaluated in vivo and in vitro. A sweet made from a regional fruit (cupuaçú) and a species of local fish (tambaqui) were used as positive and negative controls, respectively. For in vivo evaluation of dental plaque acidogenicity, the study had a crossover design, in four legs, with 19 volunteers in four treatment groups. Dental plaque pH was determined by the microtouch method before and for 60 min after food consumption. For in vitro evaluation, stimulated saliva of each volunteer was incubated with the food and pH variation was determined over 4 h. Carbohydrates were chemically determined in the flours and the majority was found to be water-insoluble. In vivo, plaque pH decreased significantly after the consumption of the sweet (p < 0.05), increased after the fish (p < 0.05), but did not change after intake of the flours (p > 0.05). In vitro, the flours were slowly fermented by bacteria present in saliva. The in vivo and in vitro findings suggest that, in the form that the main cassava flours from the Amazonian region of Brazil are customarily eaten, they may be considered to have no or very low cariogenicity.

Relationship among dental plaque composition, daily sugar exposure and caries in the primary dentition

The relationship among daily sugar exposure, dental plaque composition and caries patterns in the primary dentition is not known. Three groups of 20 children (18-48 months old) were studied: (1) caries-free (CF), (2) presenting pit and fissure caries (PFC), and (3) with nursing caries (NC). Dental caries index (dmfs) was assessed and the frequency of daily sugar exposure (TS) and its forms were estimated by questionnaires. Fluoride (F), calcium (Ca), inorganic phosphorus (P(i)), insoluble polysaccharide (IP) and mutans streptococci were quantified in dental plaque. The three groups of children were statistically different regarding daily sugar exposure. Concentrations of F, Ca and P(i) were lower and the IP and mutans streptococci statistically higher in dental plaque from NC children than those from CF children. PFC children also showed statistically lower F and P levels in their plaque than CF children. Statistically significant correlations were found between IP, TS and dmfs from NC and PFC children. A statistically significant correlation between mutans streptococci in plaque from anterior teeth and dmfs for NC children was also observed. These results suggest that the dietary sugar experience changes the biochemical and microbiological composition of dental plaque, which could partly explain the different caries patterns observed in primary dentition.

Effect of a Brazilian regional basic diet on the prevalence of caries in rats

The aim of the present study was to determine the effect of a regional basic diet (RBD) on the prevalence of caries in the molar teeth of rats of both sexes aged 23 days. The animals were divided into six groups of 10 rats each receiving the following diets for 30 and 60 days after weaning: RBD, a cariogenic diet, and a commercial diet. The prevalence and penetration of caries in the molar teeth of the rats was then analyzed. The RBD produced caries in 37.5% of the teeth of animals fed 30 days, and in 83.4% of animals fed 60 days, while the cariogenic diet produced caries in 72.5% and 77.5% of the teeth of animals fed 30 and 60 days, respectively. Rats fed the RBD for 30 days had caries in the enamel in 38% of their teeth, 48% had superficial dentin caries, and 7.5% moderate dentin caries. The effect of the RBD did not differ significantly from that of the cariogenic diet in terms of the presence of caries in rats fed 60 days. The penetration depth of the caries produced by the RBD was the same as that produced by the cariogenic diet. Our results show that the RBD has the same cariogenic potential as the cariogenic diet. Since the RBD is the only option for the low-income population, there should be a study of how to compensate for the cariogenicity of this diet.

Effect of a lactose-containing sweetener on root dentine demineralization in situ

Since lactose has been used as an excipient in powdered sweeteners, we evaluated its effect on dentine demineralization, in an in situ crossover study. Twelve adult volunteers wore palatal appliances containing 4 blocks of bovine root dentine, which were submitted 4 times a day to: distilled water (negative control), aqueous solution of powdered sweetener (Zero Cal); experimental group), 1.5% lactose solution (active group), 1.5% sucrose solution (positive control). After 15 days, microhardness was determined on dentine surface (SMH) and on the sectioned blocks (CSMH). All groups presented statistical differences in SMH before and after the treatments; water increased, while sweetener, lactose and sucrose decreased SMH. By CSMH, the only significant difference was observed after sucrose treatment. The data suggest that sweeteners containing lactose as a bulking agent may be cariogenic for root dentine.