In situ assessment of effects of the bromide- and fluoride-incorporating adhesive systems on biofilm and secondary caries.

AIM: This in situ study assessed the effects of adhesive systems containing or not fluoride and/or the antibacterial monomer 12-methacryloyloxydodecylpyridinium bromide (MDPB) on the microbiological composition of dental biofilm and enamel demineralization. MATERIALS AND METHODS: During two phases of 14 days, ten volunteers wore intraoral palatal appliances containing two slabs of human enamel according to a double-blind, crossover design. The slabs were randomly restored using a composite resin and one of the following adhesive systems: All-Bond SE(TM) (self-etch, fluoride/MDPB free adhesive, AB) and Clearfl Protect Bond (self-etch containing fluoride and MDPB adhesive, CB). The biofilm formed on the slabs was analyzed with regard to total and mutans streptococci and lactobacilli counts. Demineralization represented by integrated area of hardness × lesion depth Delta S ( ΔS) was determined on enamel by analysis of cross-sectional microhardness, at 20 and 70 µm from the restoration margin. Data were analyzed by ANOVA. RESULTS: No statistically significant difference was found either in enamel demineralization or in the microbiological composition of dental biofilm. CONCLUSION: All adhesive systems containing or not fluoride and/or MDPB tested were unable to inhibit secondary caries in the in situ model used in the present research.

An in-vitro assessment of weekly cumulative fluoride release from three glass ionomer cements used for orthodontic banding.

OBJECTIVES: To compare the in-vitro Weekly Cumulative Fluoride Release (WCFR) of three Glass Ionomer Cements (GICs) used for orthodontic banding. MATERIALS AND METHODS: The GICs tested were Granitec (Confi-Dental, Louisville, CO, USA), Bandtite (American Orthodontics, Sheboygan, WI, USA) and Ariadent (Apadana Tak Co, Tehran, Iran). Fifteen discs of each GIC were constructed (6mm diameter and 1.5mm depth). Specimens were immersed in 5 ml of deionised water and the WCFR was measured at weekly intervals, on days 1, 8, 15, 22 and 29 after immersion in deonised water, using the potentiometery device and single junction saturated calomel electrode technique (Jenway, England, UK). To compare the WCFR profile of 3 GICS, data were subjected to the one-way analysis of variance (ANOVA), and were appropriate, the Scheffe or Tamhane multiple comparison tests (post-hoc). For assessing the longitudinal changes of average WCFRs in 3 GICs, the repeated measures ANOVA were used. Post hoc tests using the Bonferroni correction was also used to compare the average WCFRs at different time-points. RESULTS: One-way ANOVA and post-hoc multiple comparison tests revealed significant differences in WCFR among 3 GICs at five time-points (p<0.05). The post-hoc multiple comparison test revealed Bandtite cement had consistently higher WCFR at all time-points, compared to Granitec and Ariadent cements (p<0.05). The one-way ANOVA test revealed significant differences in WCFR at different time-points for all GIC groups (p<0.05). The day 8 exhibited the highest WCFR for all GICs. The repeated measures ANOVA test revealed significant differences in WCFR at different time-points for all GIC groups (p<0.0005). Reviewing average WCFR on days 22 and 29, these values for Granitec, Bandtite and Ariadent GICs, were higher (p<0.05), not different (p>0.05), and significantly lower (p<0.05) than the day 1 values, respectively. CONCLUSIONS: Bandtite followed by Granitec showed higher WCFR compared to Ariadent.

Orthodontic treatment-related white spot lesions: a 14-year prospective quantitative follow-up, including bonding material assessment.

INTRODUCTION: White spots (WS) related to orthodontic treatment are severe cariologic and cosmetic complications, but they are shown to be partially reduced by remineralization or abrasion in short-term follow-ups. In this prospective study, we quantitatively analyzed changes in WS in general and in treatment-related white spot lesions (WSL) during orthodontic treatment and at a 12-year follow-up after treatment. In addition, we quantitatively compared the effects of an acrylic bonding material vs a glass ionomer cement (GIC) on WSL. METHODS: Sum areas of WS and WSL were calculated on scans of standardized photos of the vestibular surfaces of 4 teeth in consecutive orthodontic patients (median treatment time, 1.7 years) bonded with the 2 materials in a split-mouth design. Comparisons were made in 59 patients before treatment (BF), at debonding (T0), at 1 year (T1), and at 2 years (T2), and in 30 patients at a 12-year follow-up (T3) with the Friedman test followed by pairwise comparisons with the Wilcoxon matched-pairs signed rank test. Differences of the effects of acrylic vs GIC on the sum areas of WSL were tested for each observation period with the Mann-Whitney U test. RESULTS: Increases in the sum areas of WS and WSL from BF to T0 (P <0.001) were followed by significant decreases at T1 (P <0.001) and T2 (P <0.01 for WS; P <0.001 for WSL). Significant changes were also found in the sum areas for WS at T3 compared with T2 (P <0.01), but not for WSL (P = 0.328). The sum areas of WS and WSL at T3 did not return to BF levels (P <0.001). Sum areas of WSL were higher for surfaces bonded with acrylic compared with GIC for each observation period from BF to T2 (P >0.001), and from T2 to T3 (P >0.05). CONCLUSIONS: Although significantly reduced during the 12-year follow-up and significantly lower with the GIC than the acrylic material at bonding, WSL are a cariologic and cosmetic problem for many orthodontic patients.

In vitro and in vivo assessment of newly developed slow-release fluoride glass device.

BACKGROUND: The concept of constant and low levels of F intra-orally has been applied in dentistry using a controlled release delivery system in different forms of slow-release F intra-oral devices. AIM: To investigate the effect of newly shaped plastic brackets on the level of fluoride released by the devices in vitro and to compare the level of fluoride released by unilateral versus bilateral slow-release fluoride glass devices in adults in vivo. STUDY DESIGN: The phase I, in vitro assessment involved 15 slow-release fluoride glass devices divided into three groups. Group A contained five glass beads, Group B, five fluoride devices placed with the plastic brackets facing down, and Group C, five fluoride devices placed with the plastic brackets facing up. Evaluation of fluoride release was carried out daily for a week, weekly for a month, and monthly for 18 months. The In vivo phase II involved 20 adults (mean age 29.7+/-2.3 years) randomly divided and had unilateral or bilateral slow-release fluoride glass devices placed for six months. RESULTS: Groups A and B released fluoride for up to ten months. In Group C, the glass beads became loose at the end of the first month and were excluded from further analysis. There was no statistical significant difference in the mean of total fluoride released by Groups A and B. All participants showed higher salivary fluoride levels than at baseline. There was no statistically significant difference in the level of fluoride released by the bilateral and unilateral groups. CONCLUSIONS: The newly shaped slow-release fluoride glass devices showed continuous, safe, and effective fluoride release.

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.

Comparative assessment of light-cured resin-modified glass ionomer and composite resin adhesives: in vitro study of a new adhesive system.

The ideal adhesive system is one that prevents decalcifications and has sufficient bond strength to withstand untimely impact forces on bonded brackets. The purpose of this investigation was to study and compare the bond strengths and adhesive remnant indexes of light-cured resin-modified glass ionomer and conventional resin adhesives. A new light-cured resin-modified glass ionomer adhesive was compared with the conventional adhesive systems. The effects of the new adhesive, with a system of etching and using adhesive promoters on the tooth enamel, as well as microetching the brackets, were analyzed. Comparisons were made (analysis of variance and the Tukey method) between this and other adhesive systems. The new adhesive system is indicated where prevention of decalcification and increased bond strength in noncompliant patients are indicated.

Modern thoughts on fissure sealants.

It has long been known that fissure sealants are an important part of the prevention and control of dental caries in pits and fissures. However, their usage is still sporadic and generally not related to evidence-based guidelines. Caries prevalence has changed since sealants were introduced and this has significant implications for the criteria on which to select patients who would most benefit from their usage. The clinical technique for successful fissure sealant application is very moisture and operator sensitive. However, there is accumulating evidence that use of fissure sealants can be extended, given suitable investigation, to the early carious lesion as a 'preventive resin restoration'.