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The physicochemical, antibacterial, and mechanical properties of the cement used in fixed dental prostheses show particular importance in the successful treatment. The objective of this in vitro study was to prepare glass ionomer cements (GIC) containing curcumin nanocrystals, as a sealant between the prepared tooth and crown. The prepared cements containing curcumin nanocrystals with concentration of 20% and 30% were evaluated by conventional physicochemical methods, and then, the effects of adding nanocrystals on the cement water solubility and sorption were measured. Finally, the antibacterial effects of the prepared cement were evaluated against three bacterial strains of Streptococcus mutans, Staphylococcus aureus, and Escherichia coli. The results showed that the solubility and sorption of both GIC containing curcumin nanocrystals did not change significantly compared with the control ( p > 0.05 ). The cement containing 20% and 30% curcumin nanocrystals showed significant increase in antibacterial effect ( p < 0.05 ). Considering the suitable physicochemical properties and worthy antibacterial result GIC containing curcumin nanocrystals, it seems that it can be a suitable restorative material.

Background: this study aimed to evaluate the effect of the intracanal medicines including Calcium hydroxide (CH), Zinc oxide nanoparticles (nZnO), Pantoprazole (PP), and Chlorhexidine (CHX) on Enterococcus faecalis (E.faecalis) in the individual and combinatorial form in in-vitrodesign in order to introduce an effective medicine for eradication of E.faecalis. Methods: E. faecalis (ATCC 29212) was used for bacterial assays. The powder and gel forms of the tested compounds were used in the analysis. The antibacterial and antibiofilm activities of the medicines were evaluated by the minimum inhibitory concentration (MIC) determination using the broth microdilution method. The anti-biofilm effect of medicines were assessed by minimum biofilm inhibitory concentration (MBIC).The antibacterial and antibiofilm effects of antimicrobial agent combinations were detected using the checkerboard assay and determination of Fractional Inhibitory Concentration Index (FICI). Time-kill kinetics were done at zero, 2, 4, 6, 8 10, 12, and 24 h. Results: Except the MIC of the NaOCl which was significantly lower than CH, there was no statistically significant difference between groups in MIC, and MBIC. Only the mixture of chlorhexidine and zinc oxide nanoparticles (CHX-nZnO) and the mixture of pantoprazole and zinc oxide nanoparticles (PP-nZnO) had synergic effect against planktonic and biofilm form of the E.faecalis. Except for CHX and nZnO in gel form, other medicines did not show significant anti-biofilm effects against E.faecalis. Furthermore, CHX-nZnO in the gel form showed stronger anti-biofilm effects. Conclusion: Combination therapy would lead to higher antibacterial and anti-biofilm effects against E.faecaliscomparing to conventional intracanal medicaments. Among these medicines, CHX-nZnO showed promising results.

Introduction: For the long-term success of implant treatment, prevention of biological complications, including pre-implant diseases, plays an important role. The use of antimicrobial coatings is one of the prosperous methods in this field. The aim of this study is to evaluate the antimicrobial effects of healing abutments coated with gelatin-curcumin nanocomposite. Method: This study included 48 healing abutments in the form of a control group (titanium healing abutments without coating) and an intervention group (titanium healing abutments coated with gelatin-curcumin nanocomposite). The disc diffusion method was used to evaluate the antimicrobial effects of coated healing abutments against Escherichia coli, Staphylococcus aureus and Enterococcus faecalis and the results were reported in a non-growth zone area. Results and Discussion: Gelatin-curcumin nanocomposite caused significant non-growth aura for all three bacteria compared to the control group. For the control group (healing abutments without coating), the antimicrobial effects (non-growth zone) were zero. Besides, gelatin-curcumin nanocomposite had the greatest inhibiting effect on the growth of S. aureus, then E. coli and finally E. faecalis. Conclusion: The results of our study showed that the coating used was able to significantly demonstrate a non-growth zone against all three bacteria compared to the control group without coating. Further evaluations in various physicochemical, mechanical, and antimicrobial fields are necessary for the animal model and clinical phase.

Background Fixed implant-supported restorations are mainly used in dental implantology. In comparison with screw-retained implants, cement-retained prostheses have the following advantages: the ease of splinting implants; increased passive casting; and procedural similarity to conventional tooth-supported fixed partial dentures. Furthermore, they show reduced fracturing of components with better esthetic outcomes and an improved force direction, along with a reduced cost and less chairside time. Objectives The aim of this study was to evaluate the effect of different geometric changes in the dental implant abutment body on the amount of residual excess cement (REC) and the retention of cemented implant-supported prostheses. Material and methods Seventy-two straight abutments were categorized into 4 groups: vertical groove; 1 horizontal groove; 2 horizontal grooves; and ccontrol (with no geometric changes in the abutment). The access hole was partially filled and the cast copings were cemented using Temp-Bond™ NE, a non-eugenol cement. The difference in weight before and after removing the excess cement was considered as REC. Furthermore, the retention of the cast coping was measured as the force that was required to separate the cemented cast coping from the abutment. Results The mean REC values of the groups with 1 and 2 horizontal grooves were significantly different as compared to the control group (p Conclusions This study shows that the presence of 1 or 2 horizontal grooves in the abutment body significantly reduces the amount of REC in comparison with control.

Introduction. The aim of this study was to prepare a temporary restorative material containing curcumin nanocrystals and to evaluate the physicochemical properties and the antimicrobial action against Enterococcus faecalis (E. faecalis), Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli). Materials and Methods. Dental temporary restorative material was physically mixed with curcumin nanocrystals at weight percentages of 80/20 and 70/30. The prepared materials were then subjected to the physicochemical tests: Fourier transmission infrared spectroscopy (FTIR) to investigate possible bonds, X-ray diffraction (XRD) method to test the crystallinity pattern, and scanning electron microscopy (SEM) method to study the morphology of the prepared materials. Besides, the release pattern of nanocurcumin from the temporary material was evaluated using drug dissolution USP apparatus II and UV spectrophotometer. For microbial evaluation, the disk diffusion method was used against the mentioned bacteria. Results. The results showed the homogenous mixing of nanocurcumin with the temporary restorative material. Nanocurcumin showed a two-stage release pattern from the temporary material, and both types of samples containing 20% and 30% nanocurcumin had antimicrobial action against all selected bacteria. Conclusion. Extensive cellular, animal, and clinical studies are needed to demonstrate the use of temporary restorative material containing antimicrobial nanoparticles.

Background. The most common problem associated with dental implants is the abutment screw loosening. This research aimed to investigate the effect of the type of connection on screw loosening, using a finite element method (FEM). Methods. Periosave system and different types of the implant–abutment connection were used for modeling. After being measured, CAD files were modeled using CATIA software and imported to the ANSYS analysis software, and the model was loaded. Results. A force of 100 N was applied at 0.1 second, and no force was applied at 0.42 second. The screw head deformation at 0.1 and 0.42 seconds was 8 and 3.8 μm, and 7.6 and 2.8 μm at morse taper and octagon dental implant connections, respectively. The displacement rate of the internal surface of the abutment at 0.1 and 0.42 seconds was 10.7 and 8.4 μm, and 5.7 and 5.6 µm in the octagon and morse taper dental implant connections, respectively. The displacement of the implant suprastructure–abutment interface from the screw head at 0.1 and 0.42 seconds was 9 and 7 μm, and 7 and 6 μm in the morse taper and octagon dental implant connections, respectively. At intervals of 0 to 0.1 seconds and 0.6 to 0.8 seconds, the octagon connection was separated at the maximum screw head displacement and the internal part of the abutment, but the morse taper connection did not exhibit any separation. In the above time intervals, the results were similar to the maximum state in case of the minimum displacement of the screw head and the internal part of the abutment. Conclusion. Screw loosening is less likely to occur in the morse hex connection compared to the octagon connection due to the lack of separation of the screw from the internal surface of the abutment.

Introduction: The aim of this study was to compare the antibacterial effects of two gels containing zinc oxide and zinc oxide/silver nanoparticles and a mixture of calcium hydroxide and 0.12% chlorhexidine as intracanal medicaments in root canals contaminated with Enterococcus faecalis (E. faecalis) at different time intervals. Methods and Materials: After preparation and culturing of E. faecalis in 132 single root teeth, the initial count of bacteria was performed. Then, different materials as intracanal medicaments were used in periods of 3, 7 and 14 days (group 1: calcium hydroxide with 0.12% CHX paste; group 2 zinc oxide nanoparticles gel; group 3: zinc oxide/silver nanoparticles gel; group 4: normal saline as the control group). After the specified time, intracanal medicament was removed and the final count of bacteria was performed. Antibacterial effect of materials was counted by measuring the percentage reduction in the colony counts (RCC). Data were analyzed using the descriptive statistics (Mean±SD) and multi-factorial analysis of variance (by taking into account the effect of the time factor on the dependent variable). Results: There were no statistically significant differences among mean RCC of different time intervals in each group (P=0.09). However, the differences in mean RCC of different dressing materials were significant (P0.05). The minimum antibacterial effect was observed in group 4 (P

Background: Oral cancer stands among the 10 top causes of cancer death in the world. Considering the role of epidemiologic information on planning and effective interventions, the present study aimed to investigate the epidemiology of oral cancer in Iran. Materials and Methods: The required information for this systematic review study was obtained from PubMed, Google Scholar, CINAHL,SID, Medlib, Magiran and Iranmedex databases, using key words “cancer”, “oral cancer”, “squamous cell carcinoma”, “oral cavity carcinoma” and their Persian equivalents in combination with keywords of epidemiology, prevalence, etiology, frequency, and Iran from 1990 to 2014. From 1,065 related studies found, finally 25 were included to the study. Results: The mean age of 8,248 patients in 25 studies was 54.0±15.1 years. The male/female ratio for oral cancer was 1.91. Tongue with average percentage of 29.9 was the most involved site. Regarding microscopic grade, 65.7% of cases were grade 1. SCCs, accounting for an average of 70.0%, was the most common among all types of oral cancer. In the majority of studies, smoking including cigarette, hookah, and tobacco consumption was found to be a risk factor. Conclusions: The epidemiological pattern of oral cancer in Iran is somewhat similar to that of other countries. Yet the information on hand in this field is limited and considering the role of epidemiological data we suggest conducting more accurate studies to catch data that is required for effective programs and interventions.

Purpose To analyze the deformations of the peripapillary retinal pigment epithelium-basement membrane (ppRPE/BM) layer in response to procedures that lower intracranial pressure (ICP). Second, to demonstrate how shape changes may complement the mean retinal nerve fiber layer (RNFL) thickness as a measure of intracranial hypertension (ICH) and papilledema. Methods We used geometric morphometrics on spectral-domain optical coherence tomography images to analyze shape change of the ppRPE/BM layer after several interventions that lower cerebrospinal fluid (CSF) pressure. We also evaluated the effects of pressure-lowering interventions on both the anterior-posterior displacement of ppRPE/BM and the mean RNFL thickness. Forty-one patients with ICH and papilledema were studied before and after lumbar puncture (20), CSF shunt (9), and medical treatment of idiopathic ICH (23). We also compared the shape of 30 normal subjects to 23 patients whose papilledema resolved after medical treatment. Results The ppRPE/BM-layer in ICH and papilledema is characterized by an asymmetric anterior deformation that moves posteriorly and becomes more V-shaped after each pressure-lowering intervention. The differences were statistically significant for all three groups. These shape changes also occur in patients with ongoing ICH who have secondary optic atrophy (without papilledema). Posterior displacement at the margin of the ppRPE/BM layer correlated strongly with overall shape changes. Conclusions The subsurface contour of the ppRPE/BM layer is a dynamic property that changes with CSF pressure-lowering interventions. It can supplement the RNFL thickness as an indirect gauge of ICP and is particularly helpful in patients with secondary optic atrophy. Direct measurements of displacement at the basement membrane opening may serve as a more convenient office-based surrogate for shape analysis.

A 74-year-old man presented with right eye pain, swelling, photophobia, and vision loss 1 month following placement of an intravitreal dexamethasone implant (Ozurdex; Allergan, Irvine, CA) for intraocular inflammation refractory to topical therapy. Clinical examination showed visual acuity of 20/400, anterior chamber cell, vitritis, retinal vasculitis, and extensive retinitis. A vitreous biopsy was performed followed by intravitreal injections of vancomycin, ceftazidime, ganciclovir, and clindamycin. Polymerase chain-reaction testing was positive for Toxoplasma gondii . After a course of systemic therapy, intraocular inflammation subsided but visual acuity remained poor. This is the first case to the authors' knowledge of reactivation of T. gondii following intravitreal implantation of dexamethasone. [ Ophthalmic Surg Lasers Imaging Retina . 2016;47:1050–1052.]

The aim of the present study was to compare the efficacy of Nd:YAG laser and K3 rotary system in the non-surgical root canal retreatment.Sixty-one rooted human teeth were divided into two groups of 30 after root canal therapy. In groups 1 and 2 root canal retreatments were carried out using K3 rotary system and Nd:YAG laser, respectively. CBCT images were used to evaluate canal transportation and root canal debridement at coronal, middle and apical canal cross-sections. In addition, the time necessary for canal debridement and the temperature on the external root surface were calculated. Mann-Whitney U test was used for statistical analysis of data with SPSS 17 after means ± SD were calculated. Shapiro-Wilk test was used to evaluate normal distribution of data. Statistical significance was defined at P0.05.The mean time necessary for the debridement of root canals in the laser group was significantly shorter than that in the K3 group (P=0.001). However, there were no significant differences in external root surface temperatures between the two groups (P=0.17). The coronal third of the canals was cleaner in the laser group significantly (p=0.01). Less canal transportation was seen in the laser group compared to the K3 group, significantly (P=0.04).Nd:YAG is superior to K3 rotary system in the non-surgical root canal retreatment because it is faster and results in less canal transportation in the middle and apical thirds of the canals.

GPS based vehicle navigation systems have difficulties in tracking vehicles in urban canyons due to poor satellite availability. ABS (Antilock Brake System) Navigation System consists of self-contained optical encoders mounted on vehicle wheels that can continuously provide accurate short-term positioning information. In this paper, a new concept regarding ABS/GPS integration, based on fuzzy logic is presented. A fuzzy system is used to identify GPS position accuracy based on environment and vehicle dynamic knowledge. The GPS is used as reference during the time it is in a good condition and replaced by ABS positioning system when GPS information is unreliable. The MATLAB simulations manifested an improvement in location precision and the tracking capability in urban canyon conditions.

GPS provides consistently accurate positioning solutions if four or more GPS satellites can be observed. Unfortunately, this condition is usually not satisfied. ABS (Antilock Brake System) Navigation System consists of self-contained optical encoders mounted on a vehicle wheels that can continuously provide accurate short-term positioning solutions. In this paper, a new concept regarding GPS/ABS integration, based on intelligent method is presented. A fuzzy system is used to identify GPS position accuracy based on environment and vehicle dynamic knowledge. The GPS is used as reference during the time it is in a good condition and replaced by ABS positioning system when GPS information is unreliable. The MATLAB simulations manifested that the proposed algorithm improves the location precision and the tracking capability.