Direct esthetic rehabilitation of teeth with severe fluorosis: a case report

This article describes an esthetic rehabilitation of a case of severe fluorosis associated with tooth mobility and gingival recession. Direct composite technique was applied to improve the color, shape and alignment of the teeth using direct composite veneering and replacement of the missing tooth by fiber-reinforced composite bridge. One year follow up have displayed acceptable outcomes and esthetic appearance

Effect of a Combined Bleaching Regimen on the Microhardness of a Sealed Methacrylate-based and a Silorane-based Composite

Statement of Problem: The use of tooth bleaching agents has been very popular treatment in dentistry. The bleaching agents have an inherent potential to impair surface properties of existing composite resin restorations

Purpose: This study evaluated the effect of a combined bleaching regimen on the surface microhardness of a Silorane-based and a sealed methacrylate-based composite

Materials and Method: Forty-five specimens of methacrylate-based composite [Ice]and 18 specimens of Silorane composite [Filtek Silorane, 3M ESPE; USA] were prepared and randomly divided into 5 [1-5] and 2 [6-7] groups [n=9], respectively. After 8-week aging, groups 1 and 6 were remained with no treatment. In groups 2, 4 and 5, the specimens were covered by a surface sealant and light cured. In groups 3, 4, 5 and 7, the specimens were bleached with hydrogen peroxide 40% and then carbamide peroxide 20% for seven days. In group 5, after bleaching, the sealant was removed by polishing. Surface microhardness was measured and the data were analyzed using one-way ANOVA and Tukey tests [alpha=0.05]

Results: The microhardness values of groups 2 to 4 were significantly lower than that of group1 [p <0.05]. There was no significant difference among groups 1, 5, 6 and 7 [p> 0.05]

Conclusion: The combined bleaching regimen used in this study had a substantial negative effect on methacrylate and sealed methacrylate composites but not on Silorane composite

Polishing following the bleaching on the sealed composite yielded a hardness value similar to that of unsealed methacrylate composite [control]

[Barriers to blood glucose level management in the health care system: view points of patients, families and medical personnel]

Health care system barriers are major barriers to management and control of blood glucose level control. Documenting the viewpoints of patients, their families and the medical team, on these barriers is an important step towards correct planning and effective control of blood glucose. This study aimed to document and compare viewpoints of patients, their families and medical team about health care system barriers to control of glucose levels in diabetes centers of Isfahan city. This was a descriptive- comparative, cross-sectional, one stage, study of three groups, in which a total of 938 subjects, including 420 type2 diabetic patients, 420 members of their families and 98 medical staff participated. Data were collected using a researcher-designed questionnaire that was completed by subjects. Data were analyzed using descriptive and inferential statistical methods and SPSS software. Results showed significant differences between viewpoints of the 3 groups, i.e. patients, their families and the medical team regarding barriers of the health care system to blood glucose control [Pvalue< 0.001]. The medical team gave the highest importance to these barriers, while patients gave the lowest. Regarding the significant differences between the viewpoints of these three groups, it can be concluded these differences account for lack of success in controlling patient glucose levels, because medical teams focus on barriers that are not so important to patients and their families, while barriers which are important to patients and their families are less considered by members of the medical team

[In-vitro study of the surface roughness of two fissure sealants after repeated topical acidulated phosphated fluoride application]

Application of fluoride and fissure sealant has an important cariostatic effect. The impact of topical fluoride, especially APF [Acidulated Phospheted Fluoride] gel on the restorative materials has been studied. To assess the effect of repeated application of APF [1.23%] on the surface roughness of two sealant materials. In the experimental study, 135 specimens of two sealant materials were prepared, using Aluminum cylindrical molds in three groups of 45 including unfilled resin sealant [Clinpro], glass ionomer sealant [Triages] and glass ionomer sealant with covering of GC vanish. Then, these three groups were divided into three sub groups of 15 as follows: Group 1, 4, 7 [control]: No treatment. Group 2, 8, 5: Single application using APF. Group 3, 6, 9: Four times application using APF. The APF was applied on the experimental specimen every time for 4 minutes. Then, the samples were stored in the distilled water. Finally, the surface roughness of the sealants was measured using Profilometer. The statistical analysis was performed by Kruskal-Wallis and Dunn tests. Resin sealant exhibited no surface roughness changes following fluoride gel application [single or four applications]. APF produced a statistically significant increase in the surface roughness of glass ionomer with and without varnish on them. Repeated application of APF on the surface glass ionomer specimen significantly increased their surface roughness. The result of the present study revealed that APF gel application significantly increases the surface roughness of glass ionomer sealants, without any effect on the resin sealant

[ effect of chlorhexidine disinfectant on microleakage of adhesive systems in composite restorations]

Statement of Problem: Bacteria are possibly left in the cavity after its preparation and can multiply after restoration. Thus, cavity disinfection prior to restoration can be effective if it does not interfere with adhesive resin adaptation

Purpose: To evaluate the effect of the application of chlorhexidine 2% on the microleakage of composite restorations using four adhesives

Methods and Material: In this experimental study, standard class V cavities were prepared in the buccal surfaces of 88 human premolars at the CEJ. The teeth were randomly divided into 8 groups, each containing 11 teeth. Four adhesives of Scotchbond Multi-Purpose [SBMP], Excite [Ex], Clearfi SE Bond [CSEB] and iBond [iB] were used according to their manufacturer's instructions in the four control groups. In the four experimental groups, the same adhesives were used, but in the SBMP and EX groups, 2% chlorhexidine solution for 40 seconds was applied after the etching. In the CSEB and iB groups, chlorhexidine was applied before the adhesive application. The cavities were filled using Z250. The samples were immersed in 0.2% methylene blue after finishing the restorations and thermocycling. Dye penetration was evaluated using stereomicroscope after sectioning. Kruskal-Wallis and Dunn tests were used for statistical analysis

Results: There were no significant differences among the microleakage of the control groups at the incisal and gingival margins [ p >0.05]. Chlorhexidine did not affect the microleakage of the four adhesives

Conclusion: The results indicated that 2% chlorhexidine solution may not interfere with the sealing ability of the tested adhesives

Isolation of Acanthamoeba Spp. from drinking waters in several hospitals of Iran

Acanthamoeba is an opportunistic amphizoic protozoan found in different water sources including swimming pool as well as in sewage. The aim of this study was to investigate the prevalence of Acanthamoeba in tap-water samples in Iran. In this descriptive cross-sectional study, 94 samples of cold and warm tap-water were collected from different wards of hospitals in 13 cities of Iran in 2007-2008. Free residual chlorine, pH, and temperature of samples were measured. After filtration through multipore nylon membrane, samples were cultured on non-nutrient agar. Then we investigated existence of Acanthamoeba by reverse contrast phase microscope. Acanthamoeba was found in 45 samples [48%]. Thirty-four and 11 positive samples were collected from cold and warm tap water, respectively. The samples belonged to the category of 20-30 °C temperature with 0-2 ppm free residual chlorine and pH 6-7.4 showed the most coincidence to the positive cases. The greatest proportion of positive samples was obtained from Mashhad hospitals, while all samples collected from Arak and Semnan hospitals were negative. Considering the results of this study and the pathogenic role of this protozoan on patients with immunodeficiency, as well as capability of this microorganism in carrying other pathogens such as Legionella, further studies are needed. What is more important, potable water in hospitals should follow the procedure of treatment and sanitation, in order to prevent the relevant nosocomial infections

[ effect of the light activation mode on incompatibility between one-bottle adhesives and light-cured composites: an in-vitro shear bond strength study]

Adverse surface interactions between one-bottle adhesives and self-cured composites may occur similarly with light-cured composites during the use of different modes of light activation. The study examined the effect of different light activation modes of light-cured composite on the shear bond strength of 2 one-bottle adhesives with different acidity to the dentin. The experimental study was performed on 110 extracted sound molars. Then, the teeth were randomly divided into 10 equal groups [n=11]. One-Step plus [OS] and Prime and Board NT [P and B NT] were [SSI]. Soft- Start II [SSII], Pulse-Delay I [PDI], Pulse- Delay II [PDII]. Then, shear bond strength [SBS] test was performed, using an Instron at 1mm/min. The SBS was recorded in MPa. Statistical analysis included two way ANOVA with a significance level of 0.05. The highest SBS [MPa] was shown in OS conventional group [19.62] and the lowest in P and B NT, PDII [5.43]. In each group of 5 curing mode, mean SBS in P and B NT was significantly lower than that in OS as follows: In conventional; P and B NT [17.27] vs OS [19.82] in SSI; P and B NT [10.89] vs OS [13.09] in SSII; P and B NT [14.48] vs. OS [18.79] in PDI; P and B NT [5.93] vs OS [11.97] and in PDII; P and B NT [11.82] vs OS [16], [p<0.001]. In each of 2 adhesives, ranking of SBS from minimum to maximum was as follows: PDI

[Effect of light intensity and flowable liner on microleakage of class V composite resin restorations]

Statement of problem: Polymerization shrinkage stress is the most important causal factor in the microleakage of composite restorations. Relief of this stress with application of low intensity light and low elasticity liner may lead to a decrease in microleakage

Purpose: The aim of this study was to evaluate the effect of light intensity and flowable composite on the microleakage of class V microhybrid composite restorations

Materials and method: In this experimental study, 56 intact bovine incisior teeth were selected. Standard class V cavities were prepared in buccal surfaces and the teeth were randomly divided into 4 groups of 14. All teeth were restored with Tetric ceram and Excite was used as bonding system: Group 1: conventional cure with 40 seconds 550 mW/cm2 light intensity. Group 2: soft- start [s.s] cure with initial intensity [10 seconds 150 mW/cm2] and then final intensity [30 seconds 550 mW/cm2]. In groups 3 and 4: the same curing methods were as groups 1 and 2 perfomed, but flowable composite [Tetric flow] was used as liner. After 24 hours water storage samples were, thermocycled, and were immersed in 2% methylene blue for 24 hours. Dye penetration was evaluated using stereomicroscope. The statistic analyses were performed by Kruskal-Wallis and Mann-Whitney tests

Results: In general, the gingival margins had significantly more microleakage than the incisal margins [p<0.05]. Microleakage at gingival margin significantly increased with application of flowable liner and soft-start curing [p<0.05]

Conclusion: The result of this study indicated that soft start curing and flowable liner significantly increase microleakage at the gingival margin

[Effect of training on level of knowledge and attitude of female health workers on menopause and its related proble]

Introduction: Menopause is a natural period of life that means permanent cessation of menstruation and end of reproductive period, which occurs at age of 45-52 years

Objective: The aim of the study was to determine the effect of training or knowledge and attitude of female health workers working in east of Gilan province regarding menopause and its related problems

Materials and Methods: 386 female health workers responded to questions on knowledge and attitude about menopause and its related problems

Results: Findings showed that before training, 29.5% of health workers had good knowledge, 26.2% had average knowledge and 44.3% had weak knowledge and after education the results of good average and week knowledge changed to 85.2%, 13.2% and 1.6% respectively. Also their attitude to word menopause before training the levels of attitude was 31.6% positive, 63%neutral and 5.4% negative, and after training 94.7% had positive, 2.6% neutral and 0%had negative attitude

Conclusion: The results showed training promoted level of awareness and attitude about menopause and its related problems. There was a significant difference [p<0.000] between awareness and attitude of health workers and variables such as age, work experience, marital status, educational level and sources of information before and after training. Therefore training and education is the best way of promoting the level of knowledge, changing attitude and enabling them

Review on the durability of adhesive systems

Nowadays, restoring teeth with minimal sacrifice of sound tooth structure forms the basis of restorative practice. To achieve this concept, adhesives should essentially provide strong and durable bonding. Bonding to enamel is known to be more stable over time, but stability of contemporary dentin bondings are still questionable. Although their short term bonding effectiveness are sufficient, nowadays, there is an obvious trend in the development of adhesives with a simplified and easier application procedure but durabilitity of simplified adhesives in comparison to conventional adhesives is questionable. Impregnation of water through nanometer-sized prosities within hybrid and adhesive layer as nanoleakage is considered very detrimental to bond integrity and durability. Impregnation of water lead to hyrolysis [break up covalent bonds] and plasticizing of resin components due to reduction of the frictional forces between the polymer chains. Penetration and extension of water into adhesive interface is related to the permeability of simplified adhesives that behave as permeable or semipermeable membranes after polymerization and do not provide any hermetic seal on the prepared dentin. So, two-step etch and rinse adhesives with combination of primer and adhesive resin, are more susceptible to water sorption due to less-optimal hybridization and residual solvent and these are susceptible to water degradation due to the presence of hydrophilic monomer in final cured adhesive layer compared to three step etch and rinse. The surrounding resin-enamel bond plays a protective role against degradation. One-step self-etch adhesives are susceptible to water sorption and osmotically- induced water movement from dentin to bonding surface, water-tree formation and hydrolytic degradation due to the presence of acidic, hydrophilic monomer and the residual water [as essential solvent]. During solvent evaporation, the monomer/water ratio may change and subsequently result in phase separations and blistering. Therefore the hydrolytic stability of cured adhesives is of crucial importance. The best way to achieve this goal is to apply a solvent-free, neutral-pH, hydrophobic adhesive resin layer in a separate step. Three-step etch and rinse adhesives remain the "gold standard" in terms of adhesion durability. Any kind of simplification in the clinical application procedure results in a loss of bonding effectiveness. Only two-step, self-etch most adhesives closely approach this standard, and have additional clinical benefits