Comparative evaluation of caries prevalence among group of Egyptian adolescents using DMFS and ICDASII methods: a cross-sectional study

BACKGROUND

Limited data is available regarding the prevalence of dental caries as a chronic disease among adolescents using different caries assessment indices. The aim of this study was to compare and describe the prevalence of dental caries among group of Egyptian students using two caries assessment indices; DMFS and ICDAS II.

METHODS

This descriptive, cross-sectional epidemiological study included 2760 public secondary school students with age range from 15 to 18 years with permanent dentition and good general health. Presence of; retained teeth, congenital or developmental anomalies in the permanent dentition, orthodontic treatments, systematic conditions, smoking and general health problems were considered the exclusion criteria in this study. Participants were selected randomly from 8 public secondary schools in the Great Cairo, Egypt. The examination was achieved by 6 trained and previously calibrated examiners using sets of diagnostic mirrors, compressed air, a WHO probe and cotton rolls. DMFS index and ICDAS II system were used as caries detection methods. In DMFS index; the number of decayed (D), missing (M) and filled (F) surfaces was recorded, while in the ICDAS II index, the assessment of both cavitated and non-cavitated carious, missed and filled teeth with restorations /sealants was recorded. The examiners performed the oral examination using both scoring systems in an alternating manner. The collected data were explored for normality using Kolmogorov-Smirnov and Shapiro-Wilk tests. Chi square test was used to analyze the frequencies.

RESULTS

There was a statistical significant difference between the DMFS and ICDAS II methods results regarding the recorded number of caries affected teeth and cavitated teeth surfaces. The prevalence of dental caries among the investigated secondary school students was (69.56%) and (78.29%) for DMFS and ICDAS II, respectively.

CONCLUSIONS

The prevalence of dental caries among Egyptian adolescent is high. ICDAS scoring system revealed higher caries prevalence values than DMFS method. ICDAS method is the best choice for the preventive goals, while DMFS is sufficient for clinical purposes.

Preparation and characterization of dental pit and fissure sealant based on calcium sodium silicate bioactive glasses.. [DOI: 10.21203/rs.3.rs-2453592/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

This study aimed to prepare a resin based dental sealant loaded with novel bioactive glass formulated from (50 wt% calcium silicate and 50 wt% sodium silicate) with different percentages of fluorapatite. Four glass batches were formulated then characterized using Fourier Transform Infrared Spectroscopy analysis, X-ray powder diffraction analysis and Transmission electron microscopy. Density, microhardness and bioactivity testing after insertion in artificial saliva were done. Four Bisphenol-A glycerolate dimethacrylate based sealant loaded with the glass batch that showed the preeminent properties and silica fillers were prepared. The prepared sealants were compared to commercial sealants regarding flow, curing depth, compressive strength and microhardness. Sealant composition that showed comparable properties to that of the commercial sealant was selected for pH changes, ion release testing after immersion in artificial saliva for different time intervals. Results indicated the structural stability, amorphous nature, and bioactive behavior with apatite forming ability of the tested glass batches. Experimental sealant revealed comparable tested properties with lower compressive strength compared to the commercial sealants at P < 0.001. The mean pH values of the tested sealants ranged from 6.75 to 6.35 with extended calcium and phosphorus ion release up to 90 days. It was concluded that the 85 wt% calcium silicate and sodium silicate with 15 wt% fluoroapatite had the best trend regarding ion release and appetite forming ability. Sealant loaded with 65 wt% bioactive glass, 10 wt% sintered nanosilica and 10 wt% nanosilica had the best acceptable mechanical properties. The novel pit and fissure sealant is a promising bioactive and ion releasing material.

Evaluation of Charcoal and Sea Salt-Lemon-based Whitening Toothpastes on Color Change and Surface Roughness of Stained Teeth

AIM

To compare the efficacy of two naturally based commercially available whitening toothpastes charcoal and sea salt-lemon on stain removal of teeth in terms of color change and surface roughness.

MATERIALS AND METHODS

Twenty-seven intact bovine incisors were selected and randomly allocated into three main groups (n = 9) according to the tested toothpaste [I: Signal Complete 8 Charcoal; II: sea salt-lemon essence Closeup natural smile; and III: Signal Complete 8 Original (control)]. Following 4 successive days of staining protocol, each specimen in its corresponding group was brushed with the toothpaste using toothbrush simulator apparatus for three brushing cycles. Color assessment using Vita Easyshade spectrophotometer and surface roughness (Ra) measurement using contact type profilometer were performed for each specimen at baseline, after staining, and after each tooth brushing cycle.

RESULTS

Nonparametric color data and parametric surface roughness data were analyzed. The color difference (ΔE) from after-staining protocol to different tooth brushing cycles (1,2,3) showed no significant difference on each cycle between the tested groups (p >0.05). While for color difference (ΔE) from baseline to the last tooth brushing cycle 3, the difference between groups was statistically significant where group II, sea salt-lemon-based toothpaste, had a significantly lowest (ΔE ₀₀) value (p <0.001) indicating more whitening effect in relation to others. However, a significant increase in surface roughness was present in all tested groups (p <0.001); meanwhile, there was no significant difference between tested groups (p >0.05).

CONCLUSION

After three tooth brushing cycles, none of the natural whitening toothpastes or conventional toothpastes produced had effective whitening results nor completely removed the stains back to the initial baseline tooth color. Sea salt-lemon-based whitening toothpaste had a whitening effect better than the charcoal-based toothpaste. All of the tested toothpastes increased the degree of surface roughness.

CLINICAL RELEVANCE

Charcoal and sea salt-lemon-based whitening toothpastes do not guarantee to whiten nor completely remove the stains back to normal and their effects on enamel surface roughness should be highly clinically considered and managed.

The influence of different surface treatment protocols and bonding agents on the repair microtensile bond strength of six-month’ aged composite: An in vitro study

Objective: to compare the effect of three surface treatment protocols and two intermediate agents on repairing aged composite, regarding microtensile bond strength (µTBS) and mode of fracture, at two time intervals. Material and methods: Six-month aged microhybrid composite blocks, were randomly distributed into three groups, subjected to; Fine, Super Fine grit diamond burs or Erbium- Yag Laser surface treatment. Each block had both One Coat bond SL (Bond) and Brilliant Flow flowable composite (Flow) intermediate agents, alongside. Blocks were incrementally repaired using nanohybrid composite, cut into beams, then randomly subjected either immediately (IM) to µTBS test or after thermocycling (TC) for 5000 cycle. Mode of failure was determined using stereomicroscope. Data were analyzed through three-way ANOVA followed by pairwise comparison with Bonferroni correction. Kruskal Wallis test compared groups for failure mode analysis (?=0.05)Results: Super Fine grit showed the highest mean µTBS compared to control for both intermediate agents, IM and after TC at P<0.05. No difference between Fine grit and Laser application for all groups (P>0.05). IM, Bond showed the highest µTBS compared to TC, Flow for all tested groups. Beams roughened with Fine and Super Fine burs showed significantly lower adhesive failures than those roughened with Laser. Flow suffers significantly higher adhesive failure than those with Bond. For TC tested groups; beams with Super Fine bur and Bond showed significantly lower adhesive failure at P=0.029.Conclusions: Super Fine grit and Bond provide the highest µTBS and the least adhesive failure; moreover TC resulted in significant decrease in µTBS.

Assessment of craniospinal arteriovenous malformations at 3T with highly temporally and highly spatially resolved contrast-enhanced MR angiography

BACKGROUND AND PURPOSE

Patients with arteriovenous malformation (AVM) are known to have an elevated risk of complications with conventional catheter angiography (CCA) but nonetheless require monitoring of hemodynamics. Thus, we aimed to evaluate both anatomy and hemodynamics in patients with AVM noninvasively by using contrast-enhanced MR angiography (CE-MRA) at 3T and to compare the results with CCA.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained for this Health Insurance Portability and Accountability Act-compliant study. Twenty control subjects without vascular malformation (6 men, 18-70 years of age) and 10 patients with AVMs (6 men, 20-74 years of age) underwent supra-aortic time-resolved and high-spatial-resolution CE-MRA at 3T. Large-field-of-view coronal acquisitions extending from the root of the aorta to the cranial vertex were obtained for both MRA techniques. Image quality was assessed by 2 specialized radiologists by using a 4-point scale. AVM characteristics and nidus size were evaluated by using both CE-MRA and CCA in all patients.

RESULTS

In patients, 96.6% (319/330) of arterial segments on high-spatial-resolution MRA and 87.7% (272/310) of arterial segments on time-resolved MRA were graded excellent/good. MRA showed 100% specificity for detecting feeding arteries and venous drainage (n = 8) and complete obliteration of the AVM in 2 cases (concordance with CCA). Nidus diameters measured by both MRA and CCA resulted in a very strong correlation (r = 0.99) with a mild overestimation by MRA (0.10 cm by using the Bland-Altman plot).

CONCLUSION

By combining highly temporally resolved and highly spatially resolved MRA at 3T as complementary studies, one can assess vascular anatomy and hemodynamics noninvasively in patients with AVM.

Binding and distribution of three prototype calcium channel blockers in perfused rat liver

This work represents a study of the binding and distribution of three different calcium channel blockers in the Sprague-Dawley rat liver, using an in situ perfusion technique. For this purpose, [3H] desmethoxyverapamil, [3H] PN200-110 (isradipine) and [3H] azidopine were used as binding probes interacting with calcium channels. The perfusion steps of the liver involved both portal vein and thoracic inferior vena cava cannulations as inlet and outlet respectively. The subhepatic inferior vena cava was ligated to prevent leakage of the perfusate. Buffer, containing the tracer drug, was administered via the portal vein at a rate of 1 mL/min and perfusate collected at the same rate within specified time intervals during 50 min. The concentration of the tracer solutes in the perfusate's outlet increased with time, and steady state was observed for all tracers at > or = 40 min. The effect of adding cold isradipine to tracer desmethoxyverapamil, or cold verapamil to tracer PN200-110 were also assessed. First order rate constants for hepatocellular influx, efflux and calcium channel binding of the tracer substances were obtained using a simplified model from Goresky et al. These constants were mathematically manipulated and changed into permeability constants, second order binding constants, and residency times. Tracer solute influx across hepatocellular membranes is solubility-diffusion controlled, is inversely related to the molecular weights and is different in value from the efflux constants. Cold isradipine reduced the binding constant of desmethoxyverapamil by 36%, while cold verapamil reduced the binding constant of PN200-110 by 23%. Azidopine cellular distribution was low, however, binding to its receptor was analogous to desmethoxyverapamil and PN200-110. Moreover, PN200-110 had the highest residency time with no effect of cold verapamil on its receptor binding, while desmethoxyverapamil had the lowest residency time which significantly increased in the presence of cold isradipine.

[Ultrastructure of the mid-intestine muscle of the larva of Calliphora erythrocephala Meig]

The fine structure of the mid-gut muscle in larval Calliphora Erythrocephala Meig. Electron microscopy reveals and mid-gut muscle fibres to be composed of an array of actin and myosin myofilaments. The perforated Z-band divides the fibril to sarcomeres. The average length of the sarcomere in 5,34 micrometer for the non contracted muscle and 2,09 micrometer for the fully contracted muscle. The thick filaments of the fully contracted muscle pass through the spaces of the Z-structures.

[Degeneration of the brush border in the midgut of Calliphora erythrocephala Meig]

The brush border of the intestinal epithelium is described in an actively feeding larvae of Calliphora erythrocephala Meig. It will persist intact after the appearance of the first signs of degeneration of the larval intestinal cells. It will then be invaginated inside the cell forming a "microvillar dense body."