Physicomechanical Properties of Resin-Based Pit and Fissure Sealants Reinforced with Rice Husk Derived Nano Silica and Nanohydroxyapatite

@#Resin-based pit fissure sealants (RBS) are used to prevent occlusal caries in children. The success of RBS in preventing dental caries is largely influenced by its retention on the tooth surface, which is also affected by its physicomechanical properties. The physicomechanical properties of RBS can be enhanced through the addition of fillers. With the advent of nanofillers, the physicomechanical properties were improved without altering RBS flowability. The present study developed an RBS with a 70 wt% resin matrix and 30 wt% nanofillers. The resin matrix consisted of urethane dimethacrylate (55 wt%), triethylene glycol dimethacrylate (45 wt%), camphoroquinone (0.3 wt%), and 2-(dimethylamino) ethyl methacrylate (0.7 wt%). Silane-treated rice husk-derived nanosilica (20 wt%) and nanohydroxyapatite (10 wt%) were added as fillers. Clinpro, Fissurit FX, and an unfilled sealant were controls. All RBS were tested for surface roughness, Vickers hardness, flexural strength, and flowability. Statistical analysis with oneway ANOVA revealed significant differences between groups in surface roughness, hardness, flowability (p < 0.001), flexural strength, and flexural modulus (p < 0.05). Experimental sealants had higher flexural strength (78 MPa) and flow distance (29.05+1.16 mm) than commercial controls.However, the surface roughness of experimental sealants (0.25+0.08 μm) was higher than Clinpro (0.087+0.027 μm) but lesser than Fissurit FX (0.35+0.19 μm). The Vickers hardness of experimental sealants (23+1.63 VHN) was less than Fissurit FX (28.80+1.69 VHN) but higher than Clinpro (21.74+1.68 VHN). This novel RBS had physicomechanical properties comparable to commercial sealants. The use of nanosilica from rice husk makes this pit and fissure sealer sustainable and environmentally friendly in dentistry.

[Influence of dentinal region on bond strength of two different restorative materials]

The aim of this study was to determine the influence of dentinal region on shear bond strength by comparing the shear bond strength between root and coronal dentin when using a nanoionomer material [Ketac N100,3M Espe] and a fifth generation bonding material [Excite,Vivadent] applied with a resin composite [Tetric-ceram,Vivadent]. 40 extracted human incisors were used and sectioned along the cemento-enamel junction to have crown and root parts [20 parts for each material]. Facial surfaces of all parts were flattened to expose dentin. Samples were mounted in plastic rings with acrylic resin. Materials were applied according to the manufacturer instruction by using a Teflon mold. After thermo cycling [500 cycles] shear bond strengths were determined using Instron 1195 Machine at a crosshead speed of 1mm/min. Results were evaluated statistically using T student test [P=0.05]. Statistical study revealed that [Excite+T] showed significantly higher bond strength values with coronal dentin [21.98 Mpa.] than that with root dentin [10.24 Mpa]. Whereas the bond strength values of [KetacN100] with root dentin [12.95 Mpa.] was significantly higher than that with coronal dentin [6.78 Mpa.]. This study reveals to the clear influence of the dentinal region and the type of the restorative material on the shear bond strength to dentin

Microleakage in class II composite restorations with gingival margins placed entirely within dentin: total bonding vs open sandwich technique

The aim of this in vitro study was to evaluate the microleakage on the gingival margin located below the cemento-enamel junction of class II composite restorations [CR, Tetric-ceram,Vivadent] applied with a 5th generation bonding material [Excite,Vivadent] and to compare it with that seen in open sandwich restorations using a nanoionomer material [OST, Ketac N100,3M] and a composite material [Tetric-ceram]. 48 standardized box-like class II cavities were prepared on 24 noncarious premolars and divided into two groups, each of was restored with one of the two techniques: [CR, Excite +T], [OST, Ketac]. After thermocycling [500 cycles] teeth were immersed in 0.5% methylene blue solution for 24 hours, sectioned mesiodistally and then evaluated for microleakage on gingival wall according to a scale of 4 grades [0-3] using stereomicroscope. Statistical analysis was performed using Mann-Whitney U test [P<0.05]. Results showed significant differences in gingival microleakage between OST, Ketac [grade 3: 91.7%] and CR, Excite +T [grade 3:16.7%]. This study doesn't support the use of KetacNIOO in open sandwich technique applied on class II cavities with gingival margins on root dentin

Exposure of gasoline station workers to leaded gasoline in the Gaza strip: awareness and self reported symptoms

Awareness and self reported symptoms among 105 gasoline station workers in the Gaza Strip were assessed. A cross section of workers was asked to fill in a questionnaire. Workers reported high level of knowledge on health effects of leaded gasoline 88 [83.8%] and lead as an environmental pollutant 89 [84.8%]. Protective measures were poorly used. Knowledge seems not to have much influence on practice. The most common self reported symptoms were neurological symptoms including headache 78 [74.3%], fatigue 74 [70.5%], irritability 66 [62.9%], concentration difficulties 65 [61.9%], and sleep disturbance 55 [52.4%]. The prevalence of symptoms increased with increasing years of work [chi corrected=7.713, P=0.021]. Use of respiratory mask in particular can potentially limit such symptoms [chi corrected=8.325, P=0.004]

Evaluation of phakic posterior chamber intraocular implantable contact lens for high myopia

To evaluate efficacy, predictability and safety of the surgical correction of high myopia using the phakic posterior chamber implantable collamer lens. A prospective, nonrandomized, non-comparative interventional case series. Twenty seven eyes of fifteen patients aged from 20 to 46 years having high myopia were included. STAAR modified collamer implantable contact lenses [version 4] were implanted for correction of high myopia. Uncorrected visual acuity [UCVA] best-corrected visual acuity [BCVA], intraocular pressure, lens opacity analysis, postoperative inflammation and distance between the ICL and crystalline lens assessed at slit-lamp and other postoperative complications. The mean postoperative spherical equivalent [SE] was -0.629 +/- 0.98 D [range -2.25 to +1.25] for 27 eyes with mean preoperative SE -16.667 +/- 3.43 D [range 10-22 D]. 74.07% of eyes had SE +/- 1.00 D. The mean postoperative UCVA was 0.58+0.22 Snellen decimal visual acuity [from 0.2-1.00 Snellen visual acuity]. 25.9% had IOP >21 mmHg at 1 month interval. 11.11% had lens opacity with 3.7% having significant lens opacity requiring surgery. The implantation of modified collamer posterior chamber implantable contact lenses for high myopia shows adequate safety, predictability and stability. The main concerns over potential cataract formation and changing anterior segment dimensions still exist and needs long term follow-up. No financial disclosure of author in STAAR ICL

Traumatic injuries to permanent anterior teeth in children: a retrospective study

The purpose of this retrospective study was to investigate traumatic dental injuries to permanent incisors and the treatment provided to a group of children attending Prince Ali hospital. Sixty-one pediatric patients [48 males and 13 females, age range 7-14 years] were seen in the pediatric dental clinic at Prince Ali Hospital during a period of one year [2003-2004]. Data regarding dental trauma was collected from their records and analyzed. Causes of dental injuries were numerous. Falls were the most common cause of injury [77%], collision accounted for 11% of the injuries, sports for 8%, road traffic accidents for 2% and other causes in 2%. Most of traumas occurred at home [66%] followed by school [15%]. The most commonly involved teeth were maxillary permanent incisors which accounted for 89% of the injuries. The most common type of injury was uncomplicated crown fracture [70%]. The main reason for delayed presentation was unawareness of parents [50%]. Pain was the main cause of attendance to dental clinic and the main modality of treatment for delayed cases was pulp therapy. Most of the injuries were in males; in the age group 9-10 years with uncomplicated crown fracture as the main type of injury. Most cases were seen late, after three days of trauma, with pulp therapy as the main type of treatment. This finding raises the importance of awareness of the public, including school teachers, of the crucial of immediate treatment for traumatized teeth, which can help in the prognosis of treatment provided

Clinical and surgical predictors of early post operative atrial fibrillation and sustained ventricular tachycardia after cardiac surgery

Post operative Atrial Fibrillation [AF]. Occurs up to 50% in cardiac surgery patients and represent the most common post operative complication. Although malignant ventricular tachycardia [V.T.] is uncommon arrhythmic complication early after cardiac surgery - it has a negative impact on mortality. The etiology of these arrhythmias [AF, V.T] after open heart surgery is incompletely understood and their prevention remains suboptimal. Identification of patients vulnerable for post operative [AF, V.T.] would allow targeting of these patients to benefit from aggressive prophylactic intervention. The aim of this work is to evaluate the incidence and identify risk factors of [AF, sustained V.T.] early postoperatively after cardiac surgery. 40 patients with a mean of age [55 +/- 10] years old [20 male, 20 female] under went isolated elective cardiac surgery [20 patients for valve replacement and 20 patients for CAPG]. Demographic and clinical data preoperative, operative and postoperative were collected. Patients continuously monitored and hemodynamically significant [AF, VT] were recorded. Detailed analysis was performed to define the risk factors. Post operatively AF occurred in [17/40] 42.5%. The mean age for patients with postoperative AF was 55 +/- 7.3 years old compared with 47.7 +/- 9.3 years old for patients without AF P<0.05. The mean heart rate variability [RMSSD] significantly differed between patients with post operative AF and patients without [15 +/- 2.1 msec VS 25 +/- 3 msec P<0.05]. The mean of P wave dispersion for patients with po AF was significantly prolonged compared to patients without AF [80 + 11 msec VS 42 +/- 12 msec, P<0.05]. Multivariate logesitic analysis [odds ratio +/- 95% CI, P value] was used to identify the following independent predictors of post operative AF: increasing age above VS below the mean age [OR = 2.8 CI [1.2-3.5] P<0.0] valve surgery VS CAPG [OR= 2.75 CI [1.2- 3.2] P<0.05], preoperative non use of beta blockers [OR= 1.5 CI [1.1-4.2] P<0.05] Considering several operative variables, use of internal mammary artery, pulmonary venting, cardiopulmonary bypass time, and aortic cross clamping time were significantly differed between the group with AF. And the group without AF. [26.6% VS 73.4% P=0.001] [71.4% versus 28.6% P=0.001], [113.8 +/- 33.5 m versus 92.4 +/- 36.3 m, P=0.002]. [97.8 +/- 21.5, versus 71.3 +/- 9.3, P = 0.001] respectively. Only one patient developed sustained VT post operatively [2.5%] of total study population, she was female had longer pump time than patient without sustained VT [120 min VS 80 +/- 9.5 min P<0.05]; longer Aortic cross clamping time [103 min VS 60 +/- 20 min P<0.05]; had increased QT[c]D than patient without sustained VT [120 msec VS 80 +/- 5 msec, P<0.05]. Patients with and without hemodynamically significant AF and sustained VT had similar body mass index preoperative heart rate and preoperative blood pressure. AF remains the most common complication after cardiac surgery. Increasing age and type of surgery identifies patients at risk for development of AF after cardiac surgery. Female sex, longer pump time, aortic cross clamping time, are independent predictors of developing sustanined VT post operatively. Increased QT[c] dispersion, decreased HRV, Root square of the mean of the sum of the Square of differences between adjacent R-R intervals [RMSSD] and increased PWD after cordic surgery may reflect disrupted electrophysiological stability of the myocardium and thus electrophysiological substrate for triggering malignant arrhythmias

Tuberculous tenosynovitis: a rare presentation of miliary TB

We present, as a rare manifestation of miliary TB, a case of tuberculous tenosynovitis, preceding by two weeks onset of tuberculous meningitis. A gradual progressive onset of a painless swelling of the right forearm was followed by high-grade fever, headache and neck pain. A suspected diagnosis of tuberculous meningitis based upon analysis of cerebrospinal fluid [CSF] was confirmed later by positive CSF polymerase chain reaction [PCR] for mycobacterium tuberculosis. Although the patient had a positive Mantoux test of 20 mm, there was no evidence of pulmonary TB and a negative CSF smear for acid fast bacilli but a positive smear from a fine needle aspirate of the swelling of the right forearm. The antituberculous therapy led to a successful outcome

Role of non contrast helical CT in predicting the outcome of extracorporeal shock wave lithotripsy

To evaluate the usefulness of urinary calculi attenuation values from non-contrast computed tomography [NCCT] in predicting the outcome of treatment by extracorporeal shock wave lithotripsy [ESWL]. Between 1[st] January 2007 and 30[th] June 2008, we evaluated 178 patients undergoing ESWL for solitary urinary calculi. All patients had NCCT at 120 Kv and 240mA on a helical CT scanner. During each ESWL session 3000 shock waves were given to a maximum of 3.0Kv.A final plain X-ray of the kidney, ureters and bladder was taken 12 weeks after the last ESWL session. Fragments of /= 750HU, 52 [84%] needed three or fewer ESWL sessions and 57[92%] had complete clearance. Of patints with calculi of>750HU, 40 [74%] required three or more ESWL sessions, and 32[60%] had complete clearance. The best outcome was in patients with calculus diameters of<1.1 cm and mean densities of 750HU and diameter of > 1.1cm; 18[75%] needed three or more ESWL sessions and the clearance rate was only 50%. The calculus density was a stronger predictor of outcome than size alone The HU measurement of urinary calculi [stone density] on pretreatment non contrast CT predicts the stone free rates after ESWL. This might help in planning alternative treatment in patients with a probable poor outcome, and to increase the efficiency of ESWL, thus decreasing the cost of treatment

Study of interlukin-18 in viral hepatitis C patients with chronic hepatitis and hepatocellular carcinoma

Hepatitis C virus [HCV] infection represents a serious threat to human health; often resulting in liver cirrhosis and hepatocellular carcinoma [HCC]. The exact mechanisms responsible for persistent infection and long -term hepatocellular injury are poorly understood. It is hypothesized that the pro-inflammatory cytokine IL-18 may have an important role in chronic cellular immune response towards hepatocytes in the course of the disease. Of this study was to evaluate the significance of measuring IL-18 mRNA in peripheral blood mononuclear cells [PBMCs] in viral hepatitis C patients with chronic infection and HCC. Forty selected patients with chronic HCV infection [12 with compensated liver functions "group I" ; 12 with decompensated liver functions "group II"; and 16 with HCC on top of chronic HCV infection "group III"] and 10 healthy controls with matched ages and sex were studied. Using reverse- transcriptase polymerase chain reaction [RT-PCR], detection of HCVRNA in blood of patients and quantitation of IL-18 mRNA transcripts in PBMCs of patients and control were performed. This study showed a significant increase [p<0.001] in the mean value of transcriptional expression of IL-18 gene [as a ratio to that of beta-globin] in PBMCs in all patients groups compared to control. A positive [however insignificant] correlation was detected between transcriptional expression of IL-18 gene and serum albumin [r=0.446]; ALT[r=0.074] as well as prothrombin time [r=0.332] in chronic viral hepatitis patient groups [compensated and decompensated]. A significant positive correlation was found between transcriptional expression of IL-18 gene and hepatitis C viral load in all patient groups[r=0.756; 0.669; and 0.956 respectively]. These results support the hypothesis that IL-18 has an important role in the immunopathogenetic events leading to liver injury in chronic HCV infection. The antiviral action of IL-18 might be counteracted by multiple factors leading to persistent HCV infection [as IL-10]. The question becomes important whether and to what extent the HCC is influenced by IL-18. Future follow- up studies are recommended to investigate the role of monoclonal antibody to IL-18 in amelioration of liver damage and cirrhosis in such patients, in addition to further studies to highlight the role of IL-18 binding protein [BP] and Th-2 cytokines [as IL-10] as possible antagonists to the antiviral action of IL-18. Finally future- large scales studies correlating IL-18 gene expression with markers of HCC progression are recommended to gain insight into the antitumor action of IL-18 as it would be a promising new strategy to control HCC

Dengue fever as a cause of acute febrile illness in Sharkiya

The prersent work aimed at detection of dengue as a cause of acute febrile illness in Sharkiya. One hundred patients complaining of fever, headache, myalgia and arthralgia were included in the present study. Acute and convalescent serum samples were collected from each patient and tested by indirect ELISA for the presence of dengue virus immunoglobulin G. Four-fold rise in antibody titre was found in sera eight patients"from acute to convalescent". The eight patients had leucopenia and none of them showed haemorrhagic manifestations. The present study showed that dengue fever can not be ignored as a possible cause of acute febrile illness in Sharkyia. So infection control measures must be taken to prevent its spread, especially in new countries, through people comming from endemic areas. Also, it is recommended to facilitate methods for laboratory diagnosis of dengue fever for early detection and treatment

P53/WAF1 dependent pathway in squamous cell carcinoma of bladder associated with Bilharziasis

Our understanding of cellular growth control and cell cycle control has been studied extensively at the last decade. Several genes have been identified whose expression are affected by p53 gene. The waf1 is a target gene whose expression has been found to be regulated by p53. We studied p53/waf1 expression inschistosomal egyptian bladder cancer patients in an attempt for the possible use of them as genetic marker for assessment of the progression of such type of disease in egypt. For this purpose, 50 bladder tumors and their corresponding safty margins as controls were collected from nci, cairo niversity and screened for detection of p53 alterations using western blotting confirmed by pcr-sscp analysis, as well as the expression of waf1 gene using western blotting technique. Our results revealed that 20 cases [40%] showed mut-p53, 19 of them harbor abnormal pattern of sscp analysis. A significant correlation was reported between p53 and histopathological type of bladder cancer [scc and tcc, p=0.02]. We reported 21 cases [42%] showed waf1 downexpression. This study gives a dramatic example for the interaply between the oncosuppressor genes in cancer where, a very strong negative association was reported between the presence of p53 alteration [at both dna and protein levels] and waf1 expression [p=0.001]. In conclusion, this study provides an evidence that p53 may be involved in scc genetic. However, no role for p53 alterations in the progression or metastatic potential of bladder cancer. Also, p53/waf1 deficiency may not involve in bladder cancer development and/or progression

protective role of intestinal microflora [lactobacillus GG] in the pathogenesis of food allergic diseases

The aim of this study was to evaluate the role of intestinal microflora [Lactobacillus GG] in the development of food allergy in atopic patients. Sixty patients with atopic diseases due to food allergy [20 asthmatics, 20 with atopic skin diseases and 20 with allergic rhinitis] were examined for stool Lactobacillus GG and compared with 20 healthy controls. The results showed that atopic patients with food allergy in each group had a low stool Lactobacillus GG count as compared with the controls and there was an inverse correlation between stool Lactobacillus GG and both eosinophil count and serum IgE level in each group. It was concluded that there is a strong association between low Lactobacillus GG stool count and the occurrence of allergy in food allergic diseases

Diagnosis of acute appendicitis: a comparison of the efficacy of clinical signs and symptoms and laboratory investigations

the purpose of the study was to compare the validity of clinical presentations and laboratory tests in the diagnosis of acute appendicitis, the major cause of emergency surgical procedures. Patients and a total of 200 patients with suspected acute appendicitis who underwent surgery were included in the study. Clinical history, detailed physical examination, and laboratory investigations were reviewed. The postoperative findings were obtained directly from the operating surgeon. in this group, 69% had acute appendicitis, 9% had acute appendicitis with complications, and the remaining 22% had normal appendices. Right iliac fossa pain, nausea and vomiting were sensitive but not specific symptoms. Tachycardia, hypotension, and fever were of low sensitivity but high specificity. Tenderness in the right iliac fossa and rebound tenderness were highly sensitive but not specific. The WBC count was a sensitive test in the diagnosis of acute appendicitis in comparison with ultrasound examination, which showed a low sensitivity. General urine examination was not valuable in the diagnosis. acute appendicitis is a condition, which requires immediate treatment. The use of highly sensitive tests with high positive predictive value, though of low specificity, favors the appropriate diagnosis and treatment and minimizes the risk of missing cases

Surgical hemisection and orthodontic management of permanent double tooth: a New technique

Two cases of maxillary permanent double teeth, the left central incisor and the right lateral incisor, are described. Treatment comprised of surgical separation, orthodontic alignment and conservative pulp therapy. Surgical splitting and removal of one half of the double tooth resulted in an acceptable shaped tooth. Orthodontic treatment involved alignment of teeth and relief of anterior crowding. No root canal therapy was performed, and the teeth showed no evidence of increased mobility. The intervened teeth remained vital and their periodontal health was maintained. At 28 months follow-up, examination revealed good prognosis and stability

Prevalence of intestinal parasites among school children in gaza city, gaza strip

A total of 489 stool specimens was collected from school children aged six to eleven years. The target area was overcrowded with improper sewage disposal system and low socioeconomic standards. A questionnaire was designed to include relevant information. Each stool specimen was processed by the direct smear microscopy, zinc sulfate flotation technique and formol-ether sedimentation technique. This study revealed an overall prevalence at 27.6%. Six parasites were detected. Giardia lamblia [62.2%] was the most frequent species, followed by Ascaris lumbricoides [20.1%] then Entamoeba histolytica [13.3%]. The prevalence of these parasites was found to be related to age, socioeconomic and sanitation conditions. Most of the other parasitic infections were of mild intensity. There was an urgent need to correct the situation by improving the living conditions, providing facilities for the population such as modern housing, proper sewage disposal system, health education and execution of survey programs for parasites to treat the infected persons

Surgical and chemico-pathological study following subtotal thyroidectomy

A study of 15 patients with thyroid gland swelling [non-malignant] both surgically and chemicopathologically especially the effect of subtotal thyroidectomy on the level of serum calcium and phosphurs first day post-oper, second day post-oper. And seventh day post-oper, was done. Also the preoperative serum calcium and phosphorus was recorded