Ultrastructural investigation of the effect of toothpastes containing different remineralizing agents on demineralized enamel

OBJECTIVE

The present study aimed to evaluate the effect of remineralizing agents on demineralized enamel intended for use as fluoride substitutes or supplements for oral hygiene applications.

METHODOLOGY

Enamel samples were obtained from 30 bovine teeth. The enamel blocks were stored in 20 mL of demineralization solution for 72 h. They were then brushed with the following toothpaste for the remineralization protocol: NaF, NaF/SnF2 combination, NovaMin, or nano-hydroxyapatite. SEM/EDX examinations and microhardness measurements of the samples were performed to investigate the remineralization efficacy of the studied toothpaste. One-way analysis of variance (ANOVA) with post hoc Tukey's HSD test was used to analyze the change in microhardness values in different remineralization protocols (p < 0.05).

RESULTS

Differences in the mean remineralization (%RP) and hardness recovery (%HR) were determined between the groups (p < 0.05). Groups 1 and 4 showed significant differences in %RP (p < 0.05). In the SEM/EDX examinations, the samples treated with n-HAp showed an accumulation of crystal deposits on the enamel surface, although at a lower density than those treated with NaF and NaF/SnF2 combination.

CONCLUSION

The remineralization strategy in toothpaste plays an important role in enamel remineralization. NovaMin-containing toothpaste showed positive effects on the enamel surface with better Ca/P ratio. Toothpastes containing n-HAp triggered less change in the increase of microhardness values compared to other toothpastes. The use of SnF2 in toothpaste in combination with NaF significantly increased the binding of fluoride to demineralized enamel compared to toothpaste containing NaF alone.

Color stability of bleached tooth enamel brushed with different stain-removing toothpastes

OBJECTIVE

The effects of four toothpastes on the color stability of in-office bleached tooth specimens were determined.

MATERIALS AND METHODS

We evaluated an experimental toothpaste (EXP) and three commercially available toothpastes: Colgate Optic White (OPW), Aquafresh White & Protect (AWP), and Crest 3D White (CDW). OPW, AWP, and CDW contained inorganic abrasives, whereas EXP and AWP contained sodium polyphosphate. Forty-eight randomly selected human-extracted maxillary central incisors were bleached and brushed twice daily over 30 days. We analyzed the final color difference (ΔE*ab, ΔE00 , ΔWID ), arithmetic average surface roughness (Ra) of the enamel measured on days 0 and 30, and scanning electron microscopy images of enamel surfaces and toothpastes. ΔE*ab, ΔE00 , ΔWID , and Ra were analyzed using one-way analysis of variance and Tukey's test (α = 0.05).

RESULTS

ΔE*ab and ΔE00 values were significantly lower after toothbrushing with EXP, OPW, and CDW than with AWP. OPW induced the greatest positive ΔWID . Ra was significantly increased by OPW and CDW, but slightly increased by AWP, with cube-like particles, and EXP, with no particle-like structures.

CONCLUSIONS

Only EXP stabilized the color of bleached teeth without increasing the enamel surface roughness. Sodium polyphosphate with approximately 10 phosphate groups was effective at removing stains.

CLINICAL SIGNIFICANCE

The effect of toothpaste on the color stability of bleached teeth depends on the constituting abrasives and chemical components. Polyphosphoric acid has different stain-removal effects depending on its degree of polymerization. Additionally, although certain types of abrasives may be effective for color stability, they also increase the surface roughness of the enamel.

Recent Development of Active Ingredients in Mouthwashes and Toothpastes for Periodontal Diseases

Periodontal diseases like gingivitis and periodontitis are primarily caused by dental plaque. Several antiplaque and anti-microbial agents have been successfully incorporated into toothpastes and mouthwashes to control plaque biofilms and to prevent and treat gingivitis and periodontitis. The aim of this article was to review recent developments in the antiplaque, anti-gingivitis, and anti-periodontitis properties of some common compounds in toothpastes and mouthwashes by evaluating basic and clinical studies, especially the ones published in the past five years. The common active ingredients in toothpastes and mouthwashes included in this review are chlorhexidine, cetylpyridinium chloride, sodium fluoride, stannous fluoride, stannous chloride, zinc oxide, zinc chloride, and two herbs—licorice and curcumin. We believe this comprehensive review will provide useful up-to-date information for dental care professionals and the general public regarding the major oral care products on the market that are in daily use.

A novel OFF-ON-OFF fluorescence probe based on coumarin for Al3+ and F- detection and bioimaging in living cells

A novel fluorescence probe L2 based on coumarin has been designed and synthesized. The probe L2 can be used for relay recognition of metal ions Al³⁺ and anion F^- in the aqueous HEPES buffer (0.05 M, pH = 7.4), and build a OFF-ON-OFF detection system. The probe showed high selectivity and sensitivity to target ions in the process of relay recognition, and the corresponding detection limit could be as low as 0.014 μM (Al³⁺) and 0.03 μM (F^-). Besides, the geometry optimizations of probe L2 and [L2 + Al³⁺] complex were carried out using the Gaussian 16 program based on DFT, and the identification mechanism of the probe was also discussed by the mass spectrometry and theoretical calculations. Moreover, the probe has also been successfully applied to detection of target ions in living cells.

Influence of the Amount of Dentifrice and Fluoride Concentrations on Salivary Fluoride Levels in Children

PURPOSE

This study evaluated fluoride (F) concentrations in saliva of children after brushing with dentifrices containing different F concentrations (zero, 550, and 1,100 ppm F) in different quantities (full bristles, transversal technique, and pea-sized).

METHODS

Eight- to 10-year-old volunteers (<small>N</small>=24) were randomly assigned into nine experimental groups (dentifrice type versus amounts) following a double-blind, crossover protocol. After a one-week washout period (use of placebo toothpaste), stimulated saliva was collected prior to toothbrushing (baseline) and at five, 15, 30, 60, and 120 minutes after toothbrushing with one of the possible combinations. Centrifuged saliva was used for F analysis after buffering with TISAB III. Data were submitted to repeated-measures ANOVA followed by Student-Newman-Keuls' test (P<0.05).

RESULTS

Salivary F peaked at five minutes after brushing, decreasing exponentially afterward. A clear dose-response relationship was seen between F concentration/amount of dentifrice applied and the mean area under the curve (AUC) of salivary F concentrations (P<0.001). The low-fluoride toothpaste applied using transversal technique or full bristles led to a significantly higher AUC than the conventional toothpaste using a pea-sized amount.

CONCLUSIONS

Brushing with a low-fluoride toothpaste applied using the transversal technique delivers more fluoride to saliva compared to a conventional toothpaste in a pea-sized amount.

Assessment of metals in cosmetics commonly used in Saudi Arabia

Cosmetics are one of the most important sources of releasing heavy metals. Different varieties of chemicals are used in cosmetic products as ingredients and some are used as preservatives. There are concerns regarding the presence of harmful chemicals in these products. Among the harmful chemicals, cosmetic products contain heavy metals. The present study was conducted to determine the content of certain heavy metals in the products made in different countries and marketed in Saudi Arabia. Thirty-one products of different brands or misbrands of commonly used cosmetic products (hair cream, beauty cream, skin cream, hair food formula, hair gel, whitening daily scrub, shampoo, shower gel, body care, body lotion, hand wash, daily fairness, shaving cream, toothpaste, germ and beauty soap, and cream soap) were purchased from local markets of Saudi Arabia. Samples were analyzed to determine the concentrations of ten metals (lead, aluminum, cadmium, cobalt, chromium, copper, manganese, nickel, mercury, and arsenic) using inductively coupled plasma mass spectrometer (ICP-MS). Based on the maximum concentrations, the heavy metal contents were arranged in the following decreasing order: Al > Cu > Mn > Pb > Cr > Ni > Hg > Co > As > Cd in cream products, Al > Pb > Cu > Cr > Mn > Ni > Hg > As > Co > Cd in shampoo products, Al > Cu > Pb > Cr > Mn > Ni > As > Co > Hg > Cd in soap products, and Al > Cu > Mn > Pb > Cr > Co > Ni > Cd > As > Hg in toothpaste products. Since the metal concentrations may relate to specific brands, product type, color, or cost, industrialist would have to check the raw materials before they are gathered into the final products to track the source of these contaminants.

In vitro evaluation of variances between real and declared concentration of hydrogen peroxide in various tooth-whitening products

OBJECTIVES

The aim of this in vitro study was to analyze the real hydrogen peroxide (HP) concentration in various commercially available tooth-whitening products containing HP and/or carbamide peroxide (CP).

MATERIALS AND METHODS

Sixteen commercially available tooth-whitening products containing various concentrations of CP or HP were investigated. The products were divided into four groups: dentist-supervised home bleaching products (Group 1, n = 5), in-office bleaching products (Group 2, n = 4), over-the-counter bleaching products (Group 3, n = 3) and whitening toothpastes and rinses (Group 4, n = 4). The peroxide concentration was determined using the oxy-reduction titration method. All the reagents used in the study were of analytic grade and freshly prepared before the experiment.

RESULTS

The HP concentration in various dentist-supervised home bleaching products and in-office bleaching products ranged from 3.02-37.08% (expected range = 3-38%). The HP concentration of over-the-counter whitening products ranged from 1.24-5.57% (expected range cannot be estimated as no concentration of active ingredient was provided). Among whitening toothpastes and rinses, Colgate Plax whitening rinse showed more than 1% HP concentration, whereas it was lower than 0.05% in other whitening toothpastes and oral rinses (expected range cannot be estimated as no active ingredient was mentioned).

CONCLUSIONS

HP concentration of most of the professional tooth-whitening products was different from the expected concentrations, although the deviations were small and most of the products were close to the expected concentration. No concentration of active ingredient was provided for over-the-counter whitening products and no active ingredient was mentioned for whitening toothpastes and rinses.

Fluorosis and dental caries: an assessment of risk factors in Mexican children

OBJECTIVE

To determine the sources of fluoride exposure and the prevalence and severity of fluorosis and dental caries and sources of fluoride exposure in the permanent dentition of 11-year-old children.

MATERIAL AND METHODS

A cross-sectional study of 111 children attending elementary schools in the State of Mexico, where the concentration of fluoride in drinking water is < 0.3 ppm, was performed using a self-administered questionnaire was directed towards the children' mothers. The level of fluorosis was determined using both the Dean's Modified Index (ID) and the Community Fluorosis Index (CFI). The decayed, missing, filled teeth (DMFT) was recorded using methods recommended by the World Health Organization (WHO). Statistical analysis was conducted using bivariate analysis with a chi2 test; odds ratios (OR) and 95% confidence intervals (CI). Logistic regression models were used in the final model.

RESULTS

Children had a fluorosis prevalence of 52.73% (95% CI: 48.2-55.4) with CFI = 0.75 +/- 0.91 (95% CI: 0.58-0.92). The caries prevalence was 53.2% (95% CI: 50.1-56.3) with DMFT = 1.27 +/- 1.67 (D = 0.85 and F = 0.42). Children who had no fluorosis showed more caries (p = 0.001). Dental fluorosis was associated with the initial age of brushing (before age four), OR = 0.511 (0.338-0.772); frequency of brushing (three times a day), OR = 0.681 (0.483-0.958), brushing before sleeping (yes), OR = 0.664 (0.473-0.932), and applications of fluoride (yes), OR = 0.756 (0.576-0.994). Dental caries was associated with several variables, such as initial age of brushing, OR = 11.28 (4.6-27.7), frequency of brushing, OR = 0.245 (0.109-0.553), brushing before sleeping, OR = 8.03 (3.295-19.59), and applications of fluoride, OR = 14.2 (4.54-44.53). In the final regression model, the level of caries and fluorosis was significantly associated (p = 0.000) with the amount of fluoride exposure. The multivariate shows this relationship.

CONCLUSIONS

Fluorosis prevalence was high for low levels and low for more severe levels. According to the CFI in the studied example, dental fluorosis represents a public health problem in the studied sample. Dental caries was low with a predominance of tooth decay. Exposure to different sources of fluoride, was a risk factor for the development of fluorosis and a benefit with regard to dental caries.

[The application of near-infrared spectroscopy and pattern recognition to quality assessment of toothpaste samples of different brands]

The near-infrared spectroscopy (NIR) was combined with pattern recognitions method and applied to the quality assessment of toothpaste samples of four different brands. Several chemometrics approaches, such as principal component analysis (PCA), clustering analysis (CA), partial least squares (PLS), artificial neural networks (ANN) and K-nearest neighbor (kNN) were used to investigate the quality of toothpastes samples. The obtained results showed that the four clustering groups can be observed after the pretreatment of multiple scatter correction for the NIR data. It was also found that the quality of toothpastes of all the four brands was relatively stable, however, there is a significant difference in the quality between two brand kinds of toothpaste samples.

Effect of post-brushing mouthrinse solutions on salivary fluoride retention

Fluoride (F) toothpaste is one of the most effective means of caries prevention. There is also evidence that mouthrinse solutions with antimicrobial agents reduce plaque formation and gingivitis and may be used as adjuncts to daily self-performed oral hygiene for risk patients. The authors hypothesize that using these solutions--without or with just a low F concentration after brushing--will have a "wash-out" effect on F toothpaste. Mouthrinse solutions with more F might be beneficial in this respect. Two groups of 10 (Series 1) and 12 (Series II) healthy subjects were recruited. They brushed for 1 min with toothpastes containing either 1450 or 5000 ppm F. After brushing and spitting out the toothpaste, the participants in Series I rinsed for 30 sec with 10 ml of a variety of products with various F concentrations (0, 100, 226 or 900 ppm F). In Series II, they first rinsed with water after the brushing and directly thereafter with 20 ml of the post-brushing rinsing solution for 30 sec. Saliva samples in both series were collected at different time points up to 1 h and the F concentration was measured. There was significantly less F in saliva after rinsing with no F or with a low F concentration (100 ppm) compared with just brushing with a F toothpaste. Rinsing with 226 ppm F displayed significantly higher F concentrations in saliva compared with only toothbrushing. Products with a high F concentration (i.e. toothpaste with 5000 ppm F or a mouthrinse solution with 900 ppm F) produced the highest F retention in saliva compared with all other protocols. The quantity of mouthrinse solution (20 vs. 10 ml) did not seem to have any effect on the F retention. The results from both test series show that a post-brushing rinsing solution without F or with just 100 ppm F exerts a "wash-out" effect on toothbrushing with either 1450 or 5000 ppm F, which may be negative for all patients, especially those with a risk of caries. The general population will benefit more from higher concentrations of F in mouthrinse solutions and, based on the results of the present investigation, 226 ppm F (corresponding to 0.05% NaF) should be the lowest concentration used. Furthermore, caries risk patients are recommended to use a high-F toothpaste (5000 ppm F) or a post-brushing mouthrinse solution with 900 ppm F (corresponding to 0.2% NaF).

[Toothpastes: ingredients, brands, categories and their utilization]

Toothpaste is one of the most widely used dental products, with the largest sales. Its use is one of the most popular oral hygiene behaviors in developed countries. In the last 30 years there has been a large variety of changes in toothpaste composition. One of the main changes is utilizing the toothpaste as a delivery system for therapeutic agents to the oral cavity. A large variety of toothpastes can be found on the market, for different purposes: caries prevention, gingivitis prevention, anti calculus formation, dentine hypersensitivity prevention and for teeth whitening. Toothpastes have a wide range of ingredients: abrasives, humectants, preservatives, thickening or binding agents, detergents, flavoring agents and therapeutic agents. This review provides details on the ingredients of dentifrices, the evidence about the different brands and categories, and questions about their utilization.

Awareness of toothbrushing and dentifrice habits in regularly dental care receiving adults

The aim of this study was to investigate toothbrushing and dentifrice habits in a Swedish adult population with relatively high caries frequency, which received regularly dental care and to evaluate the awareness of their toothbrush technique. Sixty adult participants with high caries frequency, 29 woman and 31 men, answered a self-reporting questionnaire with 42 questions concerning their oral care, brushing technique and -habits.The responses were related to their clinical behaviour observed during a customary toothbrushing session. Fifty-three participants fulfilled both the questionnaire and the clinical observation. Half of these used toothpaste containing 1450-1500 ppm fluoride but only one of all participants was aware of the fluoride concentration used. The majority used a manual toothbrush and 95% brushed their teeth twice a day using 0.9 g toothpaste. A wide range of brushing methods and habits was observed. Sixty percent did not brush systematically. Spitting of toothpaste-saliva during brushing was performed by 60% and after brushing by 15%.The observed brushing times were significantly higher than the self reported. The observed brushing times were <1 min: 3.4%, 1-2 min: 36.7% and >2 min: 47.0%. There was a significant correlation between observed brushing time and caries activity. Rinsing with water after brushing was performed once (32%) or twice (44%) during the observations. Only 9% rinsed with toothpaste slurry after brushing. It can be concluded that the awareness of the individual toothbrushing, post-brushing behaviour and the use of fluoride toothpaste was non-optimal in the adult participants. Oral health promotion by optimalized use of fluoride toothpaste and improved post-brushing behaviour should be recommended.

Spectrophotometric determination of triclosan in personal care products

A spectrophotometric method for the determination of triclosan in personal care products was proposed. It was based on the reaction of sodium nitrite with p-sulfanilic acid in an acidic medium to form diazonium ion, with which triclosan further formed an azo compound in an alkaline medium. The resulting yellow colored product has a maximum absorption at 452 nm. A good linear relationship (r=0.9999) was obtained in the range of 0-30 mg L(-1) triclosan. A detection limit of 0.079 gL(-1) was achieved and the relative standard deviation was 0.24% (n=11) at 14 mg L(-1) triclosan. The proposed method has been applied to the analyses of triclosan in several personal care products and the results were in good agreement with those obtained by high-performance liquid chromatography.

Determination of fluoride and oxalate using the indicator reaction of Zr(IV) with methylthymol blue adsorbed on silica gel

Solid-phase spectrophotometric and visual test-methods of fluoride and oxalate determination are proposed. The methods are based on the competitive reactions of ZrOCl2 with methylthymol blue immobilized on silica gel and fluoride or oxalate in solution. Absorbance of the solid-phase reagent at 590 nm decreases with the growth of fluoride and oxalate contents in solution. The developed methods demonstrate high selectivity. The interference of Bi(III) and SO4(2-), PO4(3-) is eliminated by the addition of 0.01 mol L(-1) solution of ascorbic acid and 0.01 mol L(-1) of BaCl2, respectively. To eliminate the fluoride interference with oxalate determination 1x10(-3) mol L(-1) solution of Ca(NO3)2 at pH 1.5 was added. The anions of the organic acids were destructed prior to F- determination by ultrasonic exposition (44 kHz, intensity of < or = 10 W cm(-2) for 3 min). The proposed methods were applied to the analysis of mineral water, toothpaste and biological fluids.

Determination of fluoride in toothpaste using headspace solid-phase microextraction and gas chromatography–flame ionization detection

A new method for determination of fluoride in toothpaste employing the headspace solid-phase microextraction (HS-SPME) followed by gas chromatography/flame ionization detection (GC/FID) has been proposed. It is a development of the method for determination of fluoride using trimethylchlorosilane (TMCS) as the derivatization reagent to form trimethylfluorosilane (TMFS), with the liquid/liquid extraction (LLE) step replaced by HS-SPME. To introduce the latter, it was necessary to determine the conditions of the reaction and to optimize the two stages of the SPME procedure: extraction and desorption. The parameters of the SPME analysis using carboxen/polydimethylsiloxane (CAR/PDMS) fiber were defined and compared with the corresponding ones for the LLE method, used as a reference. Also, these two methods were compared with respect to their linearity, precision, and accuracy. Results from toothpaste analyses using these two methods were highly correlated, indicating the potential to use the SPME extraction as an inexpensive and solventfree alternative to the LLE method.

Fluoride ingestion from toothpaste and diet in 1- to 3-year-old Brazilian children

OBJECTIVE

This study estimated the total daily fluoride intake of 1- to 3-year-old children from diet and dentifrice. The constituents of the diet were divided into solids, water, milk, and other beverages, which were analyzed separately. The correlation between fingernail fluoride concentrations and the total daily fluoride intake by children was also investigated.

METHODS

Thirty-three children, living in a fluoridated area, participated in the study. Fluoride intake from diet was monitored by the 'duplicate plate' method, investigating the different constituents of the diet. Fluoride ingested from dentifrice was determined by subtracting the amount of fluoride recovered after brushing from the amount originally placed onto the child's toothbrush. Fingernails were clipped and collected on three occasions. Fluoride was analyzed with the ion-specific electrode, after hexamethyldisiloxane-facilitated diffusion. Data were tested by anova and Tukey's post hoc tests, Student's t-tests and linear regression (P < 0.05).

RESULTS

Mean (+/-SD) fluoride intake from diet and dentifrice was 0.025 +/- 0.013 and 0.106 +/- 0.085 mg/kg body weight/day, respectively, totaling 0.130 mg/kg body weight/day. A strong positive correlation (r = 0.971, P < 0.0001) was seen between the amount of dentifrice loaded onto the brush (0.49 +/- 0.30 g) and the amount of fluoride ingested during each tooth brushing (0.59 +/- 0.45 mg). Among the constituents of the diet, water and milk had a significantly higher contribution to the fluoride intake (0.18 +/- 0.11 mg/day, P < 0.0001), when compared with solids (0.07 +/- 0.05 mg/day) and other beverages (0.07 +/- 0.04 mg/day). Mean (+/-SD) fingernail fluoride concentration on the three dates of collection was 3.11 +/- 1.14, 2.22 +/- 1.47 and 3.53 +/- 1.40 mug F/g. There was no significant correlation between fingernail fluoride concentration and the total fluoride intake.

CONCLUSIONS

Most of the children are exposed to a daily fluoride intake above the suggested threshold for dental fluorosis. The dentifrice alone is responsible for an average of 81.5% of the daily fluoride intake, while among the constituents of the diet, water and milk are the most important contributors. In addition, small variations in daily fluoride intake cannot be detected in fingernails.

Is the fluoride/creatinine ratio of a spot urine sample indicative of 24-h urinary fluoride?

OBJECTIVE

The main aim of this study was to determine how representative the fluoride/creatinine (F/Cr) ratio of a spot urinary sample is of the fluoride content of a 24-h urine sample in young children aged 12-36 months. Subsidiary objectives were to: (a) evaluate the use of 24-h urine samples in monitoring fluoride exposure and (b) estimate the retention of fluoride in very young children.

METHODS

Seven healthy children residing in a fluoridated area completed the study. Dietary information was obtained using a 3-day estimated food diary followed by an interview on the fourth day. Samples of foods and drinks were analysed for fluoride content. Ingestion of fluoride from toothpaste was also measured. A 24-h urine sample and a morning spot urine sample were collected from each child.

RESULTS

The mean age of the children was 32 months (range: 16-36 months). The mean total daily intake of fluoride was 0.71 (+/-0.41) mg or 0.05 (+/-0.02) mg/kg bodyweight, of which 37% came from the diet, the remainder being from toothpaste ingestion. None of the children used any other sources of fluoride such as fluoride tablets or fluoridated salt. The mean F/Cr ratio was 1.49 (+/-0.63) mg F/g creatinine. A positive correlation (Pearson's correlation=0.76, P=0.05) between fluoride excretion estimated using the F/Cr ratio in a morning spot urine sample and fluoride excretion in a 24-h urine sample was found. There was also a positive correlation (Pearson's correlation=0.83, P=0.02) between total daily fluoride intake and 24-h urinary fluoride excretion. Less than half (43%) of the total daily fluoride intake was retained in the body.

CONCLUSIONS

The F/Cr ratio of a morning spot urine sample may be used to estimate mean 24-h urinary excretion of fluoride and therefore has potential application for larger-scale epidemiological studies where 24-h samples are impractical. Estimates of 24-h urinary fluoride excretion can be used to gauge fluoride exposure.

Effect of mixed mutans streptococci colonization on caries development

OBJECTIVE

To evaluate the clinical importance of mixed mutans streptococci colonization in predicting caries in preschool children.

METHODS

Caries prevalence was examined twice, with a 6-month interval, in 410 preschool children aged 3-4 years at baseline. A commercial strip method was used to evaluate the mutans streptococci score in plaque collected from eight selected interdental spaces and in saliva. Mutans streptococci typing polymerase chain reaction (PCR) assays (Streptococcus sobrinus and Streptococcus mutans, including serotypes c, e, and f) were performed using colonies on the strips as template.

RESULTS

Twenty variables were examined in a univariate analysis to predict caries development: questionnaire variables, results of clinical examination, mutans streptococci scores, and PCR detection of S. sobrinus and S. mutans (including serotypes c, e, and f). Sixteen variables showed statistically significant associations (P < 0.04) in the univariate analysis. However, when entered into a logistic regression, only five variables remained significant (P < 0.05): caries experience at baseline; mixed colonization of S. sobrinus and S. mutans including S. mutans serotypes; high plaque mutans streptococci score; habitual use of sweet drinks; and nonuse of fluoride toothpaste.

CONCLUSION

'Mixed mutans streptococci colonization' is a novel measure correlated with caries development in their primary dentition.

Fluoride intake and fractional urinary fluoride excretion of Colombian preschool children

AIMS

The purpose of this study was to assess the total fluoride intake and the fractional urinary fluoride excretion (FUFE) relative to the customary daily fluoride (F) ingestion in preschool children between 48-59 months of age.

DESIGN

Total fluoride ingestion, from dietary and toothpaste samples was determined in 120 young children, dwellers of four Colombian cities. A "duplicate plate" technique was used. In Colombia, table salt is fluoridated to a concentration of between 180-220 mg F/kg. Individual (n=96) FUFE values were calculated as the ratio between the total amount of F excreted in the urine and the total amount of F ingested, over a 24-hour period.

RESULTS

The average daily F-intake was 0.098 mg F/kg/day; 95% C.I. = 0.085-0.111 mg F/kg/day. The proportion of fluoride ingestion from toothpaste to the total fluoride intake was higher than 66% in all cities. The average FUFE values of subjects from each of the four Colombian cities under study did not differ significantly (ANOVA; p >0.91). The average 24-hour FUFE value for preschool children was 0.33; 95% C.I. = 0.29-0.37.

CONCLUSIONS

The results obtained suggest that preschool children residing in Colombian urban areas are ingesting amounts of fluoride above the upper limit of the proposed safe threshold. FUFE values are similar to those reported in previous studies where daily F-doses were equal or higher than 0.064 mg F/kg.

[Prevalence of dental fluorosis and additional sources of exposure to fluoride as risk factors to dental fluorosis in schoolchildren of Campeche, Mexico]

OBJECTIVE

To determine the prevalence and severity of dental fluorosis, and to evaluate supplementary fluoride sources as potential risk factors to fluorosis in school children aged 6-9.

MATERIAL AND METHODS

A cross-sectional study was carried out in 320 children attending elementary schools protected by a public preventive dental program in the city of Campeche, Mexico. A self-administered questionnaire directed to the mothers was delivered through the schools and collected in the same way. The examiners were trained and calibrated (kappa > 0.90) in modified Dean's Index. The fluorosis community index (FCI) was calculated. Bivariate analyses were made with Chi2 test; odds ratios (OR) and 95% confidence intervals were calculated. Logistic regression was used in the final model.

RESULTS

Fluorosis prevalence was 56.3%, with very mild fluorosis present in 45% of children, mild in 10%, and severe in just 1.3%. The FCI was 0.7. The multivariate model showed that the effect of the supplementary fluoride sources was different between children that started brushing with toothpaste before two years of age (OR = 6.15; IC 95% = 2.03-18.67) and after (OR = 2.14; IC 95% = 1.16-3.94).

CONCLUSIONS

Fluorosis prevalence was high for mild modalities, and low for more severe levels. According to FCI the dental fluorosis constitute a public health problem in the studied sample. Exposure to diverse fluoride sources -above and beyond the fluoridated salt program- was a risk factor for dental fluorosis in this community. Results suggest that toothpaste use in children two years of age and younger should be cautious, limited to follow current guidelines, and supervised by parents to minimize the risk of dental fluorosis.

Total and Free Fluoride in Toothpastes from Some Non-Established Market Economy Countries

In 101 fluoride toothpastes, bought in local shops in Burkina Faso (n = 3), China (n = 5), Myanmar (n = 22), Nepal (n = 19), Philippines (n = 13), Syria (n = 22), Togo (n = 7) and Vietnam (n = 10), the total and free ionisable fluoride concentrations were established. The total fluoride concentration of the toothpastes was determined by gas liquid chromatography. The amount of soluble fluoride was measured after dilution in artificial saliva and treatment of the supernatants with acidic phosphatase. The free fluoride concentration in this mixture was measured with a fluoride electrode. Twenty-five percent of all toothpastes contained less than 738 ppm total fluoride, and another 25% contained between 738 and 977 ppm fluoride. Regarding free ionisable fluoride the 25th, 50th, and 75th percentile contained < or =275, 780 and 990 ppm fluoride, respectively. Of the 61 toothpastes with declared fluoride concentration, 75% contained a total F concentration of > or =89% of the declared concentration. In 25% of these toothpastes the free ionisable fluoride was < or =55% of the declared fluoride, and in another 25% of the pastes the free ionisable fluoride concentration was > or =89% of the declared fluoride. In conclusion, deficiencies were found regarding the total as well as the free ionisable fluoride concentration of toothpastes bought in non-established market economy countries. Unclear labelling concerning the type and concentration of fluoride was often encountered. A need for quality control of fluoride toothpastes is recommended.

Prevalence of dental fluorosis in children from non-water-fluoridated Halmstad, Sweden: fluoride toothpaste use in infancy

OBJECTIVES

To determine the prevalence and severity of dental fluorosis in children aged 7-9 years from non-water-fluoridated Halmstad, Sweden, and to relate the results to their reported fluoride exposure history during infancy.

MATERIAL AND METHODS

In Spring 2002, a questionnaire distributed to a cluster random sample of 1039 parents enquired into their child's early oral health behaviors and included a "photographic toothpaste menu". The permanent upper anterior teeth (13-23) were examined clinically (+10% repeats) using a modified Thylstrup-Fejerskov Index.

RESULTS

Complete data were available for 53% (n=548) of the sampled children. The prevalence offluorosis at any level was 49% (95% CI: 45-54%), and of fluorosis with esthetic concern (TF score > or =3) 4% (95% CI: 3-6%). Based on repeat observations, reliability was good (kappa = 0.82). There was no statistically significant increased risk of dental fluorosis prevalence associated with any of the fluoride exposure risk factors examined, including reported usage of (1000 ppm) fluoride toothpaste from time of first deciduous tooth eruption.

CONCLUSIONS

While there were low levels of dental fluorosis of esthetic concern, half the children had some degree of dental fluorosis. The prevalence of dental fluorosis was not explained by the risk factors, including fluoride toothpaste usage as explored in this study.

Qualitative and quantitative analysis of tocopherols in toothpastes and gingival tissue employing HPLC NMR and HPLC MS coupling

Gingival samples treated with toothpastes containing tocopherols (vitamin E) were investigated employing HPLC chromatography. The aim was to verify that vitamin E is actually enriched in the tissue, which could have beneficial effects on oral health. After determination of the tocopherols available in the toothpastes, control samples from healthy test persons and subjects suffering from gingivitis were analyzed. Subsequently, gingival tissues from diseased test persons who treated their teeth with the toothpastes containing tocopherols using various kinds of concentrations or applications were investigated. The first step of the analysis was a fast and careful extraction employing matrix solid-phase dispersion (MSPD). Afterward, the separation of the different tocopherol homologues existing was performed by HPLC chromatography on highly selective C30 RP phases. The identification of the tocopherol homologues was performed using the on-line coupling of HPLC with NMR spectroscopy and mass spectrometry.

[In vitro evaluation of the mechanical effects of sensitive toothpastes of the Swiss market]

"Sensitive pastes" are advertised for use by patients suffering from dentin hypersensitivity. Their market share is growing. Their potential of adverse mechanical side effects on dentin are consequently of concern. The aim of this study was to assess the cleaning efficiency, the relative dentin abrasion and the surface roughness induced by ten sensitive toothpastes of the Swiss market. Cleaning efficiency was assessed planimetrically, the relative dentin abrasion was measured using a radio tracer method and the surface roughness was established using a surface scanning method. Four out of the ten tested sensitive toothpastes produced only low abrasion and surface roughening on dentin, and are consequently suitable for the use by patients with dentin hypersensitivity. The remaining six pastes are too aggressive to warrant unlimited use on exposed dentin surfaces. The pain relieving effect of active ingredients of the toothpastes was not assessed.

A new method for fluoride determination by using fluorophores and dyes anchored onto MCM-41

A new colourimetric and fluorimetric method for fluoride determination in aqueous samples based on the specific reaction between fluoride and silica has been developed and applied on real samples.

Dental health knowledge and attitudes of regularly attending mothers of high-risk, pre-school children

AIM

The aims of this study were to discover the knowledge of and attitudes towards dental health of a group of regularly attending mothers of young children at high-risk of caries, and to evaluate their toothbrushing techniques.

METHOD

As part of the baseline examination of a randomised controlled trial to test the influence of dental health counselling on the caries increment of at-risk pre-school children, 268 mothers of 334 children completed a questionnaire enquiring about their dental health knowledge and attitudes, and were also observed brushing their children's teeth.

RESULTS

Although most mothers (71%) knew that they should brush their children's teeth twice a day using a small toothbrush (94%) only 52% knew that they should use only a small pea-sized amount of paste, and only 3% knew the recommended level of fluoride in toothpaste for these at-risk children. 40% of the children insisted on brushing their own teeth and 40% of the mothers brushed their children's teeth inadequately. Although three-quarters of the mothers knew that sugary foods and drinks should be consumed only at mealtimes, only 7% knew the four foods and drinks supplying most sugar to a child's diet. Although three-quarters of mothers thought that dental decay in milk teeth was very important, only half wanted their children's carious teeth restored.

CONCLUSION

Knowledge, attitudes and behaviour about dental health among these regularly attending mothers of at-risk, pre-school children were superficial. Their attitudes to dental health of primary teeth were equivocal and their demonstrated brushing behaviour on the part of their children was inadequate.

Total fluoride intake and urinary excretion in German children aged 3-6 years

There have only been few investigations comparing total fluoride intake and the fluoride proportion excreted in urine in pre-school children. In addition, the results of available studies are conflicting. Total fluoride intake was assessed in 11 healthy children aged 3-6 years on 2 consecutive days and urinary fluoride excretion was determined. The duplicate-diet approach was used for the assessment of fluoride intake from solid and liquid foods. Fluoride intake from toothbrushing was calculated as the difference between the amount of fluoride in the paste put on the toothbrush and the drinking water (fluoride concentration 0.25 mg/l) used for rinsing vs. the fluoride amounts recovered in the toothpaste spat out and in the rinsing water. Use of fluoridated domestic salt and/or fluoride tablets was recorded. The children's intake of fluoride from food averaged 202.5+/-116.2 microg F/day. They swallowed an average amount of 273.9+/-175.6 microg F/day when brushing their teeth. Daily fluoride ingestion from all sources totalled 930.7+/-391.5 microg or 53.0+/-21.4 microg/kg body weight. On average 51.5% of the fluoride ingested was excreted in urine. The wide interindividual variation makes it necessary to evaluate the urinary excretion rate for fluoride in larger study populations with varied fluoride exposure.

Laboratory analysis of fluoride containing toothpaste available in South Africa

Since the introduction of fluoridated toothpaste more than 30 years ago, it has become by far the most widespread source of fluoride in the world and after fluoridated water the most effective at reducing dental caries. Both the total soluble and the soluble ionic fluoride present in toothpaste are important in determining the effectiveness of the paste as it is important in remineralising demineralised lesions, a characteristic of fluoride which has proven to be the most important in preventing dental caries. The purpose of this study was to evaluate toothpaste currently available to the South African public regarding total soluble and soluble ionic fluoride. A variation of the method used by Grobler et al. (1983) and Du Preez et al. (1993) in previous studies conducted in South Africa was used in preparing the samples for fluoride analysis. Measurements of fluoride concentrations were done using an ionselective electrode. For all toothpaste studied (n=62), large variations occurred for the soluble ionic fluoride (mean = 318.44 microg F/g toothpaste; median = 139.69; standard deviation = 398.77). Correspondingly a mean total soluble fluoride of 848.84 microg F/g toothpaste was found (standard deviation = 189.35; median = 857.38). From this study it can be concluded that fluoride concentrations in toothpaste available to the South African public are in line with those found in the two previous South African studies. In the absence of artificially fluoridated water, toothpaste remains the most cost-effective strategy in the prevention of dental caries in South Africa.

Risk of enamel fluorosis in nonfluoridated and optimally fluoridated populations: considerations for the dental professional

BACKGROUND

Few studies have evaluated the impact of specific fluoride sources on the prevalence of enamel fluorosis in the population. The author conducted research to determine attributable risk percent estimates for mild-to-moderate enamel fluorosis in two populations of middle-school-aged children.

METHODS

The author recruited two groups of children 10 to 14 years of age. One group of 429 had grown up in nonfluoridated communities; the other group of 234 had grown up in optimally fluoridated communities. Trained examiners measured enamel fluorosis using the Fluorosis Risk Index and measured early childhood fluoride exposure using a questionnaire completed by the parent. The author then calculated attributable risk percent estimates, or the proportion of cases of mild-to-moderate enamel fluorosis associated with exposure to specific early fluoride sources, based on logistic regression models.

RESULTS

In the nonfluoridated study sample, sixty-five percent of the enamel fluorosis cases were attributed to fluoride supplementation under the pre-1994 protocol. An additional 34 percent were explained by the children having brushed more than once per day during the first two years of life. In the optimally fluoridated study sample, 68 percent of the enamel fluorosis cases were explained by the children using more than a pea-sized amount of toothpaste during the first year of life, 13 percent by having been inappropriately given a fluoride supplement, and 9 percent by the use of infant formula in the form of a powdered concentrate.

CONCLUSIONS

Enamel fluorosis in the nonfluoridated study sample was attributed to fluoride supplementation under the pre-1994 protocol and early toothbrushing behaviors. Enamel fluorosis in the optimally fluoridated study sample was attributed to early toothbrushing behaviors, inappropriate fluoride supplementation and the use of infant formula in the form of a powdered concentrate.

CLINICAL IMPLICATIONS

By advising parents about the best early use of fluoride agents, health professionals play an important role in reducing the prevalence of clinically noticeable enamel fluorosis.

Effect of cyclodextrins and polymers on triclosan availability and substantivity in toothpastes in vivo

The aqueous solubility of triclosan is only about 10 microg/mL. This very low solubility can hamper its biological activity in the oral cavity, which could explain the mixed clinical results obtained from triclosan toothpaste trials. Triclosan availability in a silica-based toothpaste was improved through cyclodextrin solubilization. The triclosan in vivo availability was optimized through a series of phase-solubility studies and triclosan release studies. It was found that in toothpastes, natural beta-cyclodextrin (betaCD) was just as good a solubilizer as the more water-soluble betaCD derivatives. Furthermore, the amount of cyclodextrin could be reduced by as much as 60% through the addition of a small amount of carboxymethylcellulose (CMC), without affecting triclosan release from the toothpaste. Optimally, cyclodextrins resulted in an almost 3-fold enhancement of triclosan availability compared to an identical toothpaste containing no cyclodextrin. In vivo studies in humans showed that replacing triclosan with triclosan/betaCD in the toothpaste resulted in only moderate improvement in triclosan substantivity. However, replacing triclosan with triclosan/betaCD/CMC complex resulted in significant improvement in triclosan substantivity. Furthermore, the in vivo studies showed that replacing free triclosan with triclosan/betaCD/CMC complex resulted in an almost 3-fold increase in initial triclosan concentration in saliva after brushing and about 2-fold increase in duration of activity.

[GFAAS determination of trace lead in toothpaste using L'vov platform]

Sensitivity in determining low melting point metals is highly improved by means of platform technique in graphite furnace AAS. In this paper we describe a method of determining trace lead in toothpaste by this technique. The method of making the platform and the selection of the platform coating were discussed and the results with and without the platform were compared. The optimum ashing temperature, atomization temperature and experimental conditions were investigated. The interference of large amount Al and Ca in the matrix on determination of trace lead can be minimized by using platform technique. The precision of about 0.9% and detection limit of about 15 ng obtained by this improved method are much better than those by methods without platform.

In vitro investigation of the liberation of fluoride ions from toothpaste compounds in a permeation model

The most important requirement for effective topical fluoride prophylaxis from toothpaste containing fluoride is that the active fluoride agent must be chemically free, and the rapid spread of the dissolved fluoride ions over the tooth surface. Abrasive compounds in the toothpastes and the brief residence time at the site of action, the oral cavity and tooth surface must not prevent the liberation. Using a two-chamber diffusion cell and an ion-selective fluoride electrode, the content of fluoride ions in five different fluoride-containing toothpastes was determined by direct potentiometry as a function of time and the different abrasive compounds employed. The investigation has demonstrated that a reduction of the release rate of fluoride ions by nearly 50% is seen when calcium carbonate and calcium hydrogen phosphate dihydrate are used as abrasive compounds and combined with sodium fluoride.

Factors influencing the amount of fluoride toothpaste applied by the mothers of young children

OBJECTIVE

To determine the weight of dentifrice and consequent amount of fluoride placed on a toothbrush by the mothers of young children when instructed to apply a pea-sized quantity or smear of two dentifrices containing different fluoride concentrations from tubes with round or star-shaped nozzles.

SUBJECTS AND METHODS

53 mothers participated in the study and each applied the eight possible combinations of dentifrice in a random order.

RESULTS

The mean weight of dentifrice, and therefore fluoride, applied was statistically less for the smear instruction than the pea but the difference was small. Significantly less weight of Colgate 0-6 gel was applied when compared with Colgate Great Regular Flavour (GRF) but the nozzle shape had no significant effect on the weight of dentifrice applied.

CONCLUSIONS

The difference in fluoride concentration between GRF (1450 ppm F) and Colgate 0-6 gel (400 ppm F) was the most important determinant of the amount of fluoride applied.

Cleaning power and abrasivity of European toothpastes

For 41 toothpastes available to European consumers in 1995, the cleaning efficacy was evaluated in comparison with abrasivity on dentin (RDA value). For cleaning power assessment, a modified pellicle cleaning ratio (PCR) measurement method was developed. The method is characterized by a five-day tea-staining procedure on bovine front teeth slabs on a rotating wheel, standardized brushing of the slabs in a V8 cross-brushing machine, and brightness measurement by a chromametric technique. All tested products were in accordance with the new DIN/ISO standard 11,609 for toothpastes in terms of dentin abrasivity. Not a single product exceeded an RDA value of 200. The majority of toothpastes (80%) had an RDA value below 100. Only three products surpassed the reference in cleaning power. Most products (73%) had a cleaning power (PCR value) between 20 and 80. The correlation between cleaning power and dentin abrasion was low (r = 0.66), which can be explained with the different influence on dentin and stains by factors like abrasive type, particle surface and size, as well as the chemical influence of other toothpaste ingredients. Some major trends could be shown on the basis of abrasive types. The ratio PCR to RDA was rather good in most silica-based toothpastes. A lower ratio was found in some products containing calcium carbonate or aluminum trihydrate as the only abrasive. The addition of other abrasives, such as polishing alumina, showed improved cleaning power. Some active ingredients, especially sequenstrants such as sodium tripolyphosphate or AHBP, also improve the PCR/RDA ratio by stain-dissolving action without being abrasive. The data for some special anti-stain products did not differ significantly from standard products. Compared with data measured in 1988, a general trend toward reduced abrasivity without loss of cleaning efficacy could be noticed on the European toothpaste market. This may be mostly due to the increased use of high-performance abrasives such as hydrated silica.

Are sodium lauryl sulfate-containing toothpastes suitable vehicles for xylitol?

The hypothesis to be tested in this study was that toothpastes containing sodium lauryl sulfate (SLS) is unsuitable vehicles for xylitol. The bacteriostatic (and cariostatic) effect of xylitol is assumed to be caused by intracellular accumulation of xylitol-5-P in plaque bacteria. Experiments were designed to investigate whether presence of SLS would affect the uptake of xylitol by interacting with the bacterial membranes and thus inhibit xylitol-5-P formation. It was shown in an in vitro study that even very low concentrations of the strong anionic detergent SLS inhibited uptake of xylitol and xylitol-5-phosphate formation by dental plaque totally. The mild nonionic detergent ethoxylated stearyl alcohol (30x EO) had no such effect. In vivo experiments with toothpastes containing xylitol and either the strong or the mild detergent, showed that xylitol in toothpaste with SLS was not available for the plaque bacteria and gave no adaptation to xylitol, whereas in the presence of 30x EO it was available, and a xylitol adaptation was observed. Glucose metabolism, which was also studied for the plaque samples, was not significantly affected by presence of any of the 2 detergents, indicating that the amounts of xylitol in toothpastes were presumably too low to give clinical significant effects, even when mild detergents are used.

An investigation of potential desensitizing agents in the dentine disc model: a scanning electron microscopy study

Cervical dentine sensitivity (CDS) may be defined as pain arising from exposed dentine. The prefix cervical indicates the location of the sensitivity and/or its subsequent treatment. Currently the most accepted mechanism of intradental nerve activation associated with dentine sensitivity appears to be hydrodynamic in nature. The concept of tubule occlusion as a method of dentine desensitization is a logical conclusion of the hydrodynamic theory. The authors employed the dentine disc model, qualitative scanning electron microscopy (SEM) and X-ray microanalysis to investigate whether selected desensitizing agents occlude dentinal tubule orifices. Strict control procedures have been used together with various methods of application to apply these agents to human dentine discs. SEM was used to examine the degree of deposit left by the various agents on disc surfaces and X-ray microanalysis was employed to characterize the elemental composition of the deposit. Analysis of selected agents, both prior to and after application on dentine discs was performed for comparative purposes. The degree of retention of the surface deposit upon rotation with saliva supernatant for 6 h was also studied. The results of this study indicated that ferric oxalate, the active ingredient of Sensodyne Sealant, which produced initial crystal-like structures, occluding almost all the tubule orifices was superior to potassium oxalate (Butler Protect). Of the over-the-counter (OTC) desensitizing products tested, both silica- and calcium-based abrasive components were observed both on the surface and within the tubules, indicating a certain degree of therapeutic potential for these two components. These findings suggest that certain desensitizing agents have tubule occluding properties as observed in this in vitro system which, in turn, may indicate a therapeutic potential in vivo.

Studies on aluminium leaching from cookware in tea and coffee and estimation of aluminium content in toothpaste, baking powder and paan masala

Studies were conducted in order to assess the level of aluminium (Al) in samples of Indian tea, coffee, toothpaste, paan masala (mouth freshener) and baking powder. Leaching of Al from cookware while preparing tea and coffee was also studied. Experiments were also conducted to study the sequential leaching of Al from cookware by preparing tea and coffee in the presence of standard size Al sheets (coupons). A small amount of Al was found to have leached from coupons during preparation of tea. Tea leaves, were found to be a rich source of Al and a maximum of 2.2% Al is extracted in tea infusions. Coffee powder on the other hand was not found to be a rich source of Al. Baking powder was found to be a rich source of Al and 1 kg of cake prepared with 1-3 teaspoon of baking powder may contain 2-12.7 mg of Al in each serving (25 g). Toothpaste also contains a significant quantity of Al, more so, when packed in Al tubes. Ingestion pattern of Al from these items by humans is also discussed.

Biological properties of peroxide-containing tooth whiteners

Peroxides have been used in tooth whitening for more than 100 years. Current peroxide-containing whiteners can be classified into three categories: (1) those containing high concentrations of peroxides for professional use only; (2) materials dispensed by dentists and used by patients at home; and (3) over-the-counter products available directly to consumers for home use. Hydrogen peroxide (H2O2) and carbamide peroxide are the most commonly used active ingredients in these whiteners. Both peroxides have long been used safely in oral health products and are accepted by the US Food and Drug Administration. However, questions have been raised regarding the safety of at-home whiteners because the peroxides appear to constitute a new use. Substantial differences exist in the manner of application between at-home whiteners and oral health products. In addition, tooth whiteners are a mixture of various ingredients; possible interactions may occur because of the active nature of peroxides. Therefore, the safety evidence for peroxide-containing whiteners is considered inadequate. This paper will review the history of using peroxides for tooth whitening, the toxicology of H2O2 and carbamide peroxide, and available information on the safety of whiteners. The rationale and approaches for evaluating biological properties of peroxide containing whiteners are also discussed.

Fluoride levels in whole saliva of preschool children after brushing with 0.25 g (pea-sized) as compared to 1.0 g (full-brush) of a fluoride dentifrice

Concerns regarding an increased risk of dental fluorosis related to ingesting fluoride-containing toothpastes by preschool children have led to recommendations to reduce the amount of toothpaste used for young children to a pea-sized amount. The purpose of this study was to determine the effect on salivary fluoride levels of reducing the amount of toothpaste used in a preschool-age (4-5 years) population. Salivary fluoride concentrations were determined for 10 children whose teeth were brushed with both 0.25 g and 1.0 g of a fluoridated toothpaste on two separate days. Initial salivary fluoride levels following the use of 0.25 g of toothpaste were less than half of the salivary fluoride concentrations when 1.0 g of toothpaste was used, and levels returned to baseline more rapidly. The reduced salivary fluoride levels when less toothpaste is used may result in a reduced efficacy for caries prevention. However, any potential reduction in caries prevention may still be outweighed by the risk of increased fluoride ingestion with larger amounts of toothpaste in preschool children. The results of this study suggest that a reduction in the amount of a fluoridated toothpaste to a pea-sized amount be limited only to young children who are at risk of ingesting toothpaste.

Spectrophotometric determination of fluoride in dosage forms and dental preparations

The method is based upon the reaction between fluoride ions and the coloured complex of Fe(III) with methyl salicylate to form the stable, colourless hexaflouride complex of iron. The conditions of the method (pH, time and combination ratio) were studied and a standard curve was obtained for 0.01-0.08 mg NaF ml-1, at 525 nm. A study was conducted on interference with complexing anions of Fe(III), cations that react with fluoride ions and with common ingredients of dosage forms and dental preparations. The method was validated and the results showed good precision (100.16 +/- = 2.33%) comparable with that of other analytical methods. Good results were obtained in the spectrophotometric determination of fluoride ions in a stomatological gel and in a toothpaste.

Oral mucosal desquamation of pre- and post-menopausal women. A comparison of response to sodium lauryl sulphate in toothpastes

The aim of the present study was to investigate whether a difference in susceptibility to chemically induced irritation of the oral mucosa in 14 pre- and 14 post-menopausal women exists, following local exposure to sodium lauryl sulphate (SLS) in toothpastes. 4 different pastes differing only in detergent concentration present, or not, were used. The participants applied 1 cm of the different test toothpastes to a cap splint covering the teeth and the oral mucosa of the upper jaw 2 x daily for 2 min during a period of 4 days. 42 desquamative reactions of the oral mucosa (in 20 subjects) were observed, 29 and 13 in the pre- and the post-menopausal group, respectively. Desquamation was only experienced following exposure to SLS-containing toothpastes, not succeeding SLS-free paste. The results demonstrated that oral mucosa of pre-menopausal women was significantly more sensitive to SLS than oral mucosa of post-menopausal women. The difference in mucosal irritation between the 2 groups increased with increasing concentration of SLS.

The choice of controls in toothpaste studies. The effect of a number of commercially available toothpastes compared to water on 4-day plaque regrowth

Toothpastes have been shown to have an antimicrobial activity both in vitro and in vivo; this activity variably translates into a plaque inhibitory effect in vivo. Commercially available toothpastes have a complex chemical make-up and some contain additional chemicals for which improved effects against plaque have been claimed. The aim of this study was to assess the plaque inhibitory properties of 5 commercially available toothpastes compared to a rinse of water over 4 days. The study was a randomised, single-blind, cross-over design balanced for residual effects. Volunteers were rendered plaque-free at each baseline and rinsed for 1 min, under the supervision of an assistant, 2x a day with the allocated mouthrinse or toothpaste slurry. At the end of the 4-day test period, the plaque was disclosed and measured by plaque index and plaque area. The plaque measurements indicated a significant difference between the toothpastes. The order of efficacy was Colgate Total, Crest regular, Crest Tartar, Colgate regular, Colgate 0-6 gel and water. This confirms previously reported data confirming the plaque inhibitory properties of certain toothpastes compared to water. These data indicate that the choice of control toothpaste with which to compare toothpastes formulated for plaque control is important and could influence conclusions drawn from clinical trials of such products.

[Pell-Nicol, a medicinal toothpaste]

A medicinal toothpaste based on an atomized extract obtained out of sulfurous mud of Nicolina Iassy (a natural organic-mineral complex) has been formulated and physico-chemically characterized. The optimal formula has been chosen corresponding to following parameters: aspect, colour, taste, smell; weight/tube (65 g +/- 5%); Dentine Abrasion Value (D. A. V.) = 30; pH = 6.95-7.42; foaming capability of foam, in minutes = 0.40-0.60; residue on the sieve (g% = 0.09); heavy metals content; abrasive substances; g% = 32-37 at least; sodium chloride g% = 0.30 at least; firmness time = 30 sec. Also it have been effectuated rheological measurements and dynamic viscosity. The medicinal toothpaste Pell-Nicole presents a plastic behaviour with thixotropic character, which confers a good stability in time, an adequate firmness and comparable properties with others marketed products. The therapeutical effects have been tested, such as the antimicrobial and anti-inflammatory actions. The medicinal dentifrice toothpaste Pell-Nicole is recommended for gum affections, superficial chronic inflammatory forms, deep paradontopathies, as well as for a proper dental hygiene.

Micro-determination of fluoride by means of metallic sodium fusion and using fluoride-sensitive electrode

A simple and accurate method to determine the content of fluoride in non-volatile organofluoro compounds or in biological samples has been developed. The method includes the metallic sodium fusion followed by quantitative estimation of fluoride using fluoride-sensitive electrode.

Fluoride and abrasive content in commonly used dentifrices on the Kenyan market

About one decade ago, a heated debate on the appropriateness of fluoride dentifrices in Kenya culminated in the introduction of no-fluoride brands. Analysis of dentifrices that were available on the market in 1989/1990 confirmed two distinctly different categories, the fluoride and the low or no-fluoride types. Among the former, the mean ionic fluoride concentration ranged between 0.4 and 1.36 mg/g while the total fluoride concentration ranged between 1.15 and 114.68 mg/g. The low or no-fluoride dentifrices had less than 0.03 mg/g ionic fluoride and less than 2.14 mg/g total fluoride. The mean abrasive (powder) content ranged between 26.5 g% and 78.5 g%. The gel categories had markedly lower powder values than the pastes. The ash values of the powders ranged between 15.8 g% and 85 g% and did not have an obvious relationship with the powder content. Despite the obvious risk of increasing exposure to excessive fluoride among children, presently, the situation has reverted to the pre-debate time. Given the ubiquitous nature of ingestable fluoride in the region, provision of guidelines and guidance on the sale of dentifrices by the government and consumer organisations, and increased accountability of the manufacturers are recommended.