ABSTRACT
The prevalence of soft drinks and the growing use of tooth colored restorative materials aroused the need for the current research. This research aimed to determine the actual impact of Cola drinks on the surface roughness of some widely used contemporary toot-colored restorative technique that provides both quantitative data [Ra, um] and qualitative representation through three dimensional Interferometric Microscopic [3DIM] images. Six direct tooth-colored restorative materials were selected. The materials include hybrid composite [z250], nanofilled composite [Filtek supreme], an ormocer [Definite], a poly acid modified composite [Dyract Extra], a giomer [Beautifil] and a resin modified glass ionomer [Fuji II LC]. Two variants of Cola drinks were used for immersion of the materials, these were Coca Cola regular and Coca Cola light. Based on previous international surveys, three regimens for the frequency of intake were followed. These were low intake [immersion once a day], medium intake [5 times a day] and high intake [10 times a day]. The immersion pattern was performed in a way simulating a real consumption pattern which was determined by a pilot study on young adults. The tested restorative materials were stored in artificial saliva at 37[degree sign] C when not exposed to the drink to simulate the clinical condition. The immersion regimens were followed for one week. Surface roughness was assessed at base line and after one week. The results showed that both Cola drinks significantly increased the surface roughness of the tested specimens, surprisingly; Cola light had more damaging effect. The adverse effect of Cola drinks was found to be material dependant. Moreover, the results clarified that the negative impact of Cola drinks becomes more pronounced by increasing the frequency of intake. Within the scope of this study, it could be concluded that consumption of Cola drinks adversely affect the surface roughness of the esthetic restorative materials, particularly, glass ionomer containing or based restorative materials. Careful selection of the restorative materials for the patients according to their soft drinking habits [type and frequency] is recommended. Finally, it is worth to mention that dietary awareness in general public health programs is an important issue and should be effectively applied
ABSTRACT
Many antiseptics and antibiotics are used for claries control; nevertheless, recent attempts have been conducted to find natural products in order to avoid their side effects. Shiitake mushroom, the 2nd most edible mushroom worldwide which has various uses in alternative medicine was chosen for our study. The purpose of the present study was to determine the anticaries efficacy of three shiitake extracts [chloroform, ethyl acetate and aqueous] against S. mutans and lactobacilli. The dried shiitake, cultivated in Egypt for the first time, was used for extracts preparation. Clinical isolates were identified through culture specificity, morphology and biochemical tests and then enumerated. Antibacterial activity was assessed using agar diffusion method, where 40 plates were seeded with each bacterial isolate. Three wells were made in each plate and each well contained 10 ul from each tested reagent. Commercial and standard chlorhexidine preparations were used as positive control. It was found that for both types of bacteria, chloroform extract had the most profound inhibitory effect that even surpassed both chlorhexidine agents. Ethyl acetate and aqueous extracts were not effective on the lactobacilli, while for the S. mutans ethyl acetate was more effective than the aqueous one. The difference between all groups was statistically significant. The data obtained from the commercial chlorhexidine were highly correlated with the standard one. The results of the present study suggested that shiitake chloroform extract would be a useful natural alternative to chlorhexidine and has potential to be used in food additives and oral care products for caries control
ABSTRACT
Purpose: The aim of this study was to evaluate the influence of a novel Microcid Etchant Gel [Saremco] on enamel-composite shear bond strength [SBS] as compared to a traditional 35% phosphoric acid etching gel [3M ESPE]. The etching patterns and elemental compositions of the tested enamel surfaces were also assessed using scanning electron microscopy [SEM] and energy dispersive X-ray [EDX] spectrometric analysis
Methods: The labial surfaces of human incisors were ground flat. The surface of each specimen was divided into two halves; the first half was etched using the traditional etchant white the other half was etched with the Microcid etchant. The SBMP[+] [3M] bonding system was applied and a specially constructed split mold and holder were used during resin composite [Z250, 3M] insertion
Results: On using t-test, there was no statistically significant difference between the recorded mean SBS values of the traditional [16.3+/-4.9] and the Microcid [14.5+/-3.9 MPa] etching gels groups [P>0.05]. Chi-squared [x[2]] analysis of failure modes revealed also no statistically significant difference between both groups [P>0.05]. In this study the tested etching gels resulted in different micromorphological changes at enamel surfaces. Qualitative comparison of the elemental profiles of both etched and control groups using EDX analysis showed no conspicuous variations
Conclusion: The utilization of the novel Microcid Etchant Gel with its advantagous Visual Etch Control concept for enamel etching did not provide unique characteristics encouraging its use as a traditional etchant substitute
ABSTRACT
Purpose: This study was to examine the bond strength of a resin composite restorative material to coronal and radicular dentine treated with two "all-in-one" bonding systems [Prompt-L-Pop [PL]; IBond [IB]]; in comparison to two and three steps bonding systems [Single Bond [SB]; Scotchbond Multipurpose Plus [SBMP+]]. SEM was used to examine the tooth-restoration interface [hybrid layers and resin tags]
Methods: Sixty human mandibular premolars were selected for this study. The proximal surface of each mounted tooth was ground hat exposing underline dentine. The prepared teeth were randomly assigned into the proposed four groups [10 teeth each]. Each evaluated bonding system was applied on the coronal and radicular dentine for each test sample then the composite was applied using a split molds with two close circular holes [2 X 2.5mm each]. Samples were tested in shear in an Instron at a cross-head speed of 0.5mm/min. After that, the mode of failure was identified. For each group, five representative samples were prepared for SEM
Results: In general, the SBS values of all tested groups to coronal dentine were higher than the corresponding radicular ones except with PL. ANOVA test revealed statistically significant difference [P
Conclusions: "All-in-one" bonding systems have compromised bonding potentials not only to coronal but also to radicular dentine. Moreover; there is no correlation between the resin tags infiltration or hybrid layer thickness, and the SBS values