A Comparative Evaluation of Three Methods of Disinfection of Gypsum Casts and the Changes in Surface Roughness and Dimensional Accuracy after Disinfection-An Ex Vivo Study.

BACKGROUND: One of the major problems of everyday dental practice is cross-contamination. It can place office personnel, dentists, and patients at risk of acquiring serious illness. Disinfection helps in controlling this cross-contamination to an extent. The evaluation was done to find the efficient disinfection method on gypsum casts. AIMS: The aim of this study is to evaluate and compare the efficacy of three methods of disinfection of gypsum casts, namely, chemical disinfection by immersion, spray method, and microwave method, and also to evaluate and compare changes in surface roughness and dimensional accuracy between the three methods after disinfection. MATERIALS AND METHODS: Ex vivo and experimental study. Thirty participants were selected, and impressions of the maxillary arch were made using polyvinyl siloxane impression material. Ninety type IV die stone gypsum casts were poured. It was divided into three groups and was subjected to chemical disinfection by immersion and spray methods, and microwave method. The disinfected casts were evaluated for microbial growth, surface roughness, and dimensional accuracy. It was performed by using the one-way analysis of variance test and paired t-test followed by the Kruskal - Wallis test and Wilcoxon signed rank test (α = 0.05). RESULTS: Microwave disinfection was more effective than both immersion and spray chemical disinfection methods (P < 0.010 and <0.001). The surface roughness of the microwave-irradiated casts had significantly increased after disinfection. However, there were no significant dimensional changes by any of the methods of disinfection. CONCLUSION: Within the limitations of the study, the microwave method of disinfection is more effective in eradicating microorganisms when compared to chemical methods of disinfection by immersion and spray methods.

Paternal stress alters synaptic density and expression of GAP-43, GRIN1, M1 and SYP genes in the hippocampus and cortex of offspring of stress-induced male rats.

Adverse experiences during pregnancy have a negative impact on the neuronal structure and behavior of offspring, but the effects of a father's life events on the outcome of progeny are scarce. The present study is intended to investigate whether paternal stress affects the offspring brain structure, especially those regions concerned with learning and formation of memory, namely the hippocampus (HC) and prefrontal cortex (PFC), and also the expression of certain genes linked to learning and memory in the offspring. Induced stress to male rats by five stressors, one per day followed by allowing them to mate with the normal, unstressed female. Synaptophysin immunoreactivity was assessed in the tissue sections of the HC and PFC as well as expression of genes concerned with learning and memory was evaluated by RT-PCR in the progeny of stress-received males. The progeny of stressed rats had reduced antisynaptophysin immunoreactivity in the HC and PFC. The synaptic density in HC was less in the A-S (Offspring of male rats who received stress during adulthood) and PA-S (offspring of male rats who received stress during both adolescence and adulthood) than in P-S (offspring of male rats who received stress during adolescence) and C-C (offspring of control) groups. Similar results were observed even in the PFC. The results of post hoc tests proved that the HC and PFC of the progeny of stress-exposed rats exhibited considerably less synaptic density than control (P<0.05), and the levels of expression of GAP-43, GRIN1, M1, and SYP genes in HC and PFC were down-regulated. This study concludes that paternal adverse experiences can affect the offspring's synaptic plasticity and also the genes, which can regulate learning and formation of memory.

Public Awareness on Perio-systemic Interplay: A Cross-Sectional Survey in South India.

BACKGROUND: The oral cavity has been referred to as "the gateway to overall health." It is also said to be the meeting point of medicine and dentistry. AIMS: Our study sought to determine the extent to which the public was aware of the connection between oral/periodontal conditions and general health. SETTINGS AND DESIGN: The observational cross-sectional study's questionnaire was sectioned into oral health awareness, systemic influence on oral health, and personal oral health assessment. MATERIALS AND METHODS: A total of 994 responses were recorded and a Chi-square test was performed to uncover the relationships using SPSS version 22.0. According to responses, 70% of the population on average comprehended the responses to the majority of the oral health awareness-related questions. RESULTS: It has been noticed that only 30% of the general public was aware of the prevalent health issues like diabetes, hypertension, and malnutrition's impact on dental health. However, more than 60% had confidence in their oral health and gave a rating of at least 5. CONCLUSION: The study indicates that a good number of the population was prioritizing their oral health. However, there exists a definitive need to improve oral health awareness thereby ameliorating the overall health of an individual.

Validation of Diagnostic Utility of Salivary Urea in Patients with Chronic Kidney Disease in Chennai: A Cross-Sectional Study.

BACKGROUND: Serum urea levels are essential for the diagnosis of chronic kidney disease (CKD), as they are a measure of renal function. Salivary urea has been used as an alternative to serum urea in patients with CKD. AIM: To estimate serum urea levels and their correlation with salivary urea levels in order to validate the use of saliva as an alternative diagnostic tool for renal dysfunction. PATIENTS AND METHODS: Thirty healthy individuals and 150 patients with CKD (30 from each CKD stage) were recruited for the study. Serum and salivary samples were collected to estimate the urea levels, and statistical analyses were performed. RESULTS: Statistically significant (P < 0.05) differences in the mean serum and salivary urea levels were observed between the healthy and each stage of the CKD group; significance at P < 0.05 was observed within the stages of CKD as well. Correlation analysis also showed significant differences between the serum and salivary urea levels at each stage of the disease. Receiver operating characteristic analysis revealed a higher area under the curve of 0.917 at a 95% confidence interval with a salivary urea cut-off of 28.25 mg/dl (sensitivity and specificity: 88% and 84%, respectively). CONCLUSION: The variability in salivary urea levels in the early and late stages suggests the use of salivary urea in the late stages of CKD. It is suggested that salivary urea levels may be used as an alternative to serum to assess and monitor the progression of renal impairment along with other standard renal function markers.

Success rate of immediately loaded implants in the posterior zone.

Dental implants are considered an ideal treatment for a missing single tooth. Immediate loading of implants can hasten the procedure, providing comfort to the patients. Recently, immediate loading of implants has gained much importance as it helps hasten the procedure and provides more comfort to patients. A previous systematic review published 5 years ago compared the success rates between immediate and conventional loading. There are several factors that influence the success rate of implants that were not discussed in detail in the previous review. Hence, the present systematic review is done to report differences in the outcomes from single implant restorations of missing teeth in the posterior region in patients who were subjected to immediate loading and conventional loading. A follow up for 1 year was done. Electronic databases of Medline, Scopus, and Web of Science were searched for publications in the English Language during May 2021. The search results yielded 306 articles, out of which 225 were excluded based on title and abstract screening. Screening of the remaining 81 full text articles yielded 14 original research articles that satisfied the predefined inclusion criteria. Meta analysis was not possible due to the heterogeneity of the data. The overall success rate of the immediate loading of a single implant is 94.31%. Implants in the maxillary region had a higher survival rate than those in the mandibular region. The age range between 18 and 80 years showed good prognosis and outcomes in older individuals. Good oral hygiene was emphasized for all patients to prevent any secondary conditions or delays in healing.

A split-mouth randomized controlled trial to compare the rate of canine retraction after a soft tissue procedure compared against a corticotomy procedure for accelerated tooth movement.

Background and Aim: Various methods to accelerate the orthodontic tooth movement have been used, among which corticotomy is considered to be the most common one. The suggested reasoning for such acceleration was the regional acceleratory phenomenon (RAP). Since the RAP is a property of both the hard and soft tissues, we designed a soft tissue flap procedure to compare the effects with the conventional corticotomy procedure. A split-mouth study was conducted where the two procedures were assessed in a single participant. Patients and Methods: The total sample size was calculated to be 40 with 20 participants in each group. The rate of tooth movement was the primary outcome measure, and the secondary outcomes were dentoalveolar changes, which were studied in both the conventional corticotomy and the flap-only procedure based on a cone-beam computed tomography (CBCT) wherein the alveolar bone density (BD) around canines, tipping, and rotational changes in canines, premolars, and molars were assessed. Results: Corticotomy resulted in greater canine angulation, lesser canine rotation and premolar rotation, and greater molar rotation compared with flap elevation, but these differences were statistically insignificant. Conclusion: Though the corticotomy resulted in higher BD, the differences were statistically insignificant. There was no significant difference in the rate of space closure assessed by the two techniques compared.

In Vitro Evaluation of marginal adaptation of polyether ether ketone and zirconia copings.

Background: Polyether ether ketone (PEEK) has emerged as a new thermoplastic material with potential applications as a restorative material. Aim: This study aimed to evaluate the marginal adaptation of PEEK copings compared to zirconia copings using field emission scanning electron microscopy. Materials and Methods: A freshly extracted maxillary central incisor was prepared for a full-coverage restoration following standard principles of tooth preparation. The tooth was sent to a laboratory for fabrication of samples using computer-aided design and manufacturing (CAD/CAM). Twenty samples of polyether ether ketone (PEEK) copings (group A) and 20 of zirconia copings were fabricated (group B). The copings were scanned under a field emission scanning electron microscope and measurements were taken at four distinct points. The marginal adaptation over the buccal, lingual, mesial, and distal margins for both groups was evaluated. One-way analysis of variance (ANOVA) and independent t test were applied. Results: Our findings indicate that PEEK showed better marginal adaptation than zirconia at all measurement points. The mean marginal gap value of the PEEK group was 33.99 ± 8.81 µm and of the zirconia group was 56.21 ± 15.07 µm. On comparing marginal adaptation among the mesial, distal, buccal, and lingual aspects, PEEK showed better adaptation on all four margins, with the best adaptation on the buccal margin that had the lowest mean gap value of 29.27 ± 6.07 µm. The zirconia group adapted best at the distal margin, with a lowest mean gap value of 53.58 ± 15.25 µm (P ≤ 0.05). Conclusion: PEEK copings had better marginal adaptation and fit compared to zirconia copings. It may have applications as a restorative material in fixed prostheses.

Antimicrobial Efficacy of Blended Essential Oil and Chlorhexidine against Periodontal Pathogen (P.gingivalis)-An In Vitro Study.

Background: Essential oils (EOs) have a considerable amount of therapeutic and preventive effect in treating dental diseases due to their wider potential as antibacterial and anti-inflammatory agents. EOs like virgin coconut oil, eucalyptus oil, peppermint oil thyme oil, and clove oil, when used in combination, may further have enhanced antimicrobial effects. However, limited information exists on the synergistic effect of these oils when used in combination, especially on the primary periodontal pathogen Porphyromonas gingivalis. Aim: The current study aims to compare the antimicrobial efficacy of commercially available EO on the periodontal pathogen, P. gingivalis, in comparison to chlorhexidine (CHX). Materials and Methods: Antimicrobial efficacy of EO and CHX was assessed at various concentrations against the periodontal pathogen P. gingivalis, by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Results: P. gingivalis was seen to be sensitive at a MIC of 100 µg/ml and 50 µg/ml concentration of the EO, which is regarded as the MIC of EO against P. gingivalis and CHX effectively inhibited microbial growth at 0.4 µg/ml. Conclusion: A combination of EOs possesses a potent antibacterial activity against P. gingivalis, and the antibacterial efficacy increases with increasing concentration of EOs.

Comparative Evaluation of Various Lens and Ring Flash Combination for Intraoral Photography.

BACKGROUND: Extraoral and intraoral dental photographs serve as preoperative records and document the entire treatment. Correctly composed orthodontic photographs are crucial for remote diagnosis and may serve as a bulwark against medicolegal challenges. MATERIALS AND METHODS: In this prospective study, intraoral frontal photographs of patients with ideal occlusion were taken using two types of lenses (EF-S 18-55 mm f/3.5-5.6 IS STM lens (Canon, Tokyo, JP), SP 90 mm F/2.8 MACRO VC lens (Model F017 Tamron, NY, USA)) and two different ring flash systems (Meike FC-100 Macro Ring LED Light (Meike, China), Macro Ring flash Lite YN-14EX (Yongnuo digital, China)). The combination of lens and flash used was grouped into four groups. Twenty-eight intraoral photographs of patients were taken. An image quality assessment survey was distributed among two groups - 50 orthodontists and 50 other dental specialists. RESULTS: The participants were asked to assess all the intraoral images and subjectively score them on a scale of one to ten, with one being very poor and ten being excellent, considering the sharpness, color, brightness, contrast, and overall quality of the image. The general dentists rated the images taken with a 90-mm macro lens and ring flash as the best quality photographs. Images obtained using an 18-55 mm lens and ring LED received significantly lesser scores and were graded good by dentists. CONCLUSION: This combination of lens and flash may prove a valuable investment in the long-term aiding in excellent dental images for diagnosis and treatment monitoring.

Bovine babesiosis in India: Estimation of prevalence by systematic review and meta analysis.

Bovine babesiosis is a serious threat to the livestock sector especially in tropical countries like India. Understanding the epidemiology of the disease in the country is essentially important in strategizing the available methods to effectively control the disease. Keeping this as the background, the present study was undertaken to estimate the pooled prevalence of bovine babesiosis in India. The relevant literature pertaining to bovine babesiosis was identified and a total of 49 studies published between 1983 and 2018 were included in the final systematic review and meta-analysis. Meta-analysis was conducted using meta-package of R software and prevalence estimates were calculated. Bovine babesiosis was reported from 21 states of India with pooled prevalence estimate of 6% (95% CI = 4%-9%) using random effect model. Zone wise analysis revealed highest pooled prevalence in the west zone and north zone (8%) followed by east zone (7%), central zone (6%), south zone (4%) and northeast zone (4%). The results of meta-analysis indicated high variability between studies. In addition, the pooled seroprevalence was high (29%) compared to prevalence of active infection (5%) of bovine babesiosis in India. Further, the pooled prevalence estimate of B. bigemina infection in India was more (7%) compared to B. bovis infection (1%). The estimation of prevalence of active infection and seroprevalence separately will helps to understand the actual disease prevalence in the country. The study indicated the wide prevalence of bovine babesiosis in India which urges for immediate mitigation strategies.

Molecular epidemiology on seasonal variation of yellow mosaic disease incidence in blackgram (Vigna mungo L. Hepper) with its vector Bemisia tabaci.

The yellow mosaic disease (YMD) of blackgram caused by Mungbean yellow mosaic virus has emerged as a serious threat to grain legume production, especially in Southeastern Asia. Seasonal incidence of YMD with its vector population was assessed in three different agroclimatic zones of Tamil Nadu in India for three consecutive cropping seasons namely, Rabi 2018 (October-December), Summer 2019 (March-May), and Kharif 2019 (June-August) at three different time intervals viz., 20, 40, and 60 days after sowing (DAS). For all three seasons, disease incidence and whitefly count were recorded for a resistant and susceptible variety of blackgram in fields without any vector control intervention. The highest disease incidence (87%) was observed in the Panpozhi location during the summer season followed by Vamban and Coimbatore locations. The whitefly count was made through both visual count and yellow sticky traps. The whitefly population was highest at 20 DAS and decreased with the increasing age of crop for all the three locations assessed. Molecular epidemiology was analyzed by determining latent infection of mungbean yellow mosaic virus (MYMV) using molecular diagnosis. Latent infection was found to be well pronounced in the Coimbatore location during the Kharif season, where the crop was asymptomatic in both the resistant and susceptible varieties for all the three time periods assessed. The latent infection of MYMV observed in Coimbatore and Vamban ranged from 16.6 to 83.3% in both resistant and susceptible varieties for all three seasons. In Panpozhi, the latent infection of MYMV ranged from 16.6 to 66.6% for the susceptible variety (CO-5) for all three seasons observed. However, in the Panpozhi location, the resistant variety (VBN-8) failed to record any latent infection.

Anti-microbial efficacy of root canal preparation in deciduous teeth with manual and rotary files: A randomized clinical trial.

Background: In a pulpectomy, the eradication of microbes from the primary root canal is accomplished through biomechanical preparation, which could be carried out with either manual or rotary instruments. Aims: The objective of this clinical trial was to evaluate the efficiency of manual K-files, H-files, and Kedo-S Square rotary files in reducing microbial flora after canal preparation in primary molars. Materials and Methods: This randomized clinical trial consisted of 45 primary molars requiring pulpectomy. The teeth were randomly allocated to one of the three groups: Group I: Manual K-files, Group II: Manual H-files, and Group III: Kedo-S Square rotary files, based on the type of instrumentation. Pre-and Post-instrumentation sampling was performed using clean absorbent paper points and kept in a clean Eppendorf tube having thioglycolate broth as the transport medium. Culturing was performed on agar media from which both aerobic and anaerobic microbial counts were estimated. Collected data were statistically analyzed using one-way analysis of variance (ANOVA) and Wilcoxon signed-rank test. Following root canal preparation, 87-89% reduction of the aerobic and anaerobic microbial load was noted in group I, whereas it was an 89-92% reduction in group II and a 93-95% reduction in group III. Results: Biomechanical preparation with Kedo-S Square rotary file showed higher efficacy in microbial reduction compared to manual instrumentation. Conclusion: Manual and rotary files were equally effective in removing root canal microbes. Biomechanical preparation with a KedoS Square rotary file resulted in greater microbial efficacy. Hence In children, effective root canal cleaning in a short period of time is a major consideration.

Prevalence of electronic cigarette usage among medical students in Saudi Arabia - A systematic review.

The systematic review aimed to report the prevalence of electronic cigarette (e-cigarette) usage among medical students in Saudi Arabia. Electronic databases were searched for scientific research articles published from January 2010 until December 2020. The data search was performed in electronic search engines such as PubMed, Google Scholar, Scopus, Web of Science, Medline, Embase, Cochrane, and Saudi Digital Library. A total of five research articles that qualified the eligibility criteria were analyzed for qualitative data. The sample size in the included studies ranged from 229 to 1007 participants. The prevalence of e-cigarette usage ranged from 10.6% to 27.7% among medical students in Saudi Arabia. Studies have also reported that the prevalence of e-cigarette usage is higher among the male population in comparison with the female population. The prevalence of e-cigarette usage among medical students in Saudi Arabia is high. Similar to tobacco smoking, e-cigarette usage is a major public health issue and concern among the younger population because they have potential benefits in some and are harmful to some and also it is still unclear whether they are effective for quitting smoking. Regulatory bodies must focus and initiate strict laws and policies to minimize the sales of these products to the younger population. Health promotion strategies need to be developed to reduce the usage of e-cigarettes.

Triple-negative breast cancers with expression of glucocorticoid receptor in immune cells show better prognosis.

Background: Glucocorticoid receptor (GR) is shown to have variable frequency of expression in invasive tumors of the breast. Investigation of additional nuclear receptors like GR in receptor negative tumors like triple negative breast cancer (TNBC) may have prognostic and therapeutic significance. Methods: Expression of GR was evaluated by immunohistochemistry in 175 tumors of invasive breast cancer with long term follow up. GR Expression was separately evaluated in invasive tumor cells, stromal cells and tumor infiltrating lymphocytes (TIL's). Staining pattern was categorised as positive when more than 1% of the cells stained in each subpopulation of cells. Disease free survival was analysed between GR positive and negative status by Kaplan Meier analysis. Results: Of the 175 tumors, 121 (70%) were ER positive, 53 (30%) were ER negative and 29% (51) were triple negative. 74% (130/175) tumors showed expression of GR in invasive tumor cells while (84%) 147/175 had expression in TIL's. No significant difference in distribution of GR was noted between ER positive and ER negative tumors (78% vs 66%, p-0.1). Of the TNBC's 54% (28/51) and 70% (36/51) showed expression of GR in invasive tumor and TIL's respectively. Overall, GR positive tumors had significant better survival than GR negative tumors (mean survival time of 85 vs 59 months respectively, p-0.04) Contrary to the reports that GR expression in TIL's are associated with immunosuppressive activity in model systems, TNBC's with increased expression of GR in immune cells were associated with better survival (Mean survival time 74 vs 41 months, log rank test- p-0.03). TNBC tumors which were GR negative had higher lymph node metastases (p-0.04) and none of the other clinical features like age, menopausal state, tumor size and grade were different between GR positive and negative tumors within TNBC. Conclusions: Glucocorticoids (GC) are often used to alleviate the adverse symptoms during chemotherapy. Determining the GR status is of importance due to the pro cell survival effect of the glucocorticoids mediated through GR during chemotherapy. Though GC mediated effects on chemotherapy are controversial, our results indicate favourable effects in TNBC.

How do we improve adolescent diet and physical activity in India and sub-Saharan Africa? Findings from the Transforming Adolescent Lives through Nutrition (TALENT) consortium.

OBJECTIVE: Adolescent diet, physical activity and nutritional status are generally known to be sub-optimal. This is an introduction to a special issue of papers devoted to exploring factors affecting diet and physical activity in adolescents, including food insecure and vulnerable groups. SETTING: Eight settings including urban, peri-urban and rural across sites from five different low- and middle-income countries. DESIGN: Focus groups with adolescents and caregivers carried out by trained researchers. RESULTS: Our results show that adolescents, even in poor settings, know about healthy diet and lifestyles. They want to have energy, feel happy, look good and live longer, but their desire for autonomy, a need to 'belong' in their peer group, plus vulnerability to marketing exploiting their aspirations, leads them to make unhealthy choices. They describe significant gender, culture and context-specific barriers. For example, urban adolescents had easy access to energy dense, unhealthy foods bought outside the home, whereas junk foods were only beginning to permeate rural sites. Among adolescents in Indian sites, pressure to excel in exams meant that academic studies were squeezing out physical activity time. CONCLUSIONS: Interventions to improve adolescents' diets and physical activity levels must therefore address structural and environmental issues and influences in their homes and schools, since it is clear that their food and activity choices are the product of an interacting complex of factors. In the next phase of work, the Transforming Adolescent Lives through Nutrition consortium will employ groups of adolescents, caregivers and local stakeholders in each site to develop interventions to improve adolescent nutritional status.

Animal disease surveillance: Its importance & present status in India.

Animal disease surveillance encompasses systematic collection of long-term data on disease events, risk factors and other relevant parameters followed by analyzing the same with reference to temporal and spatial characteristics to arrive at a conclusion so that necessary preventive measures can be taken. In India, the animal disease surveillance is done through National Animal Disease Reporting System, which is a web-based information technology system for disease reporting from States and Union Territories with the aim to record, monitor livestock disease situation and to initiate the preventive and curative action in a swift manner during disease emergencies. National Animal Disease Referral Expert System is a dynamic geographic information system and remote sensing-enabled expert system that captures an incidence of 13 economically important livestock diseases from all over the country and also provides livestock disease forecasting. The laboratories under State and Central governments, several research institutes under the Indian Council of Agricultural Research and veterinary colleges are involved in livestock disease diagnosis including zoonotic diseases. An integrated surveillance system is necessary for early detection of emerging/zoonotic diseases in humans. This review provides information on disease reporting and surveillance systems in animal health sector and the need for One Health approach to improve and strengthen the zoonotic disease surveillance system in India.

Prevalence and Pattern of Self-medication with Alternative Medicine: Treatment-switch Analysis in Oral Submucous Fibrosis Patients.

AIM: The aim of this study was to investigate prevalence and pattern of self-medication with alternative medicine (ALM) among oral submucous fibrosis (OSF) patients with emphasis on treatment-switch analysis. METHODS: A total of 115 OSF patients were recruited and subjected to scientifically validated questionnaire. Two groups were identified: S-ALM: patients who have previously received modern medicinal treatment but switched to ALM; and DN-ALM: patients who started ALM from De Novo. RESULTS: A total of 37 (32.18%) patients reported use of the ALM at some point of time. Twenty-five (67.56%) switched to ALM, whereas 12 (32.43%) patients used ALM from De Novo. The pattern of switching to ALM in short period was significantly prevalent in patients with advanced stages (stage III and IV) as compared to early stages (stage I and II) of OSF. Clarified butter, glycerin, and honey were the most commonly used ALM in both the groups. The most common reasons for switching to ALM were the cost of treatment (32.00%), longer duration of medicinal treatment (24.00%) and ineffectiveness of the medications (24.00%). CONCLUSIONS: ALM usage is common in OSMF patients with significant percentage of patient switched from modern medicine to ALM. Therapeutic efficacy of ALM in OSF needs exploration in future.

Effect of prosthetic framework material, cantilever length and opposing arch on peri-implant strain in an all-on-four implant prostheses.

AIM: To evaluate the effect of prosthetic framework material and cantilever length on peri-implant strain in mandibular all-on-four implant-supported prostheses with different types of arch antagonist forces. MATERIALS AND METHODS: Models simulating a completely edentulous mandibular arch fabricated in heat-cured acrylic resin were used. On the acrylic models, four implants were placed at regions 34, 32, 42, and 44 simulating all-on-four implant placements. Implant-supported screw-retained fixed prosthesis frameworks were fabricated using three different materials (cobalt-chromium, zirconia, and polyetheretherketone) and with three different cantilever lengths (zero mm, 15 mm, and 25 mm). Strain gauges were attached on the model at the buccal and lingual positions of each implant. Forces simulating opposing natural dentition, conventional complete denture, and the parafunctional habit were applied to the models. The peri-implant strain in each strain gauge was recorded. RESULTS: Least peri-implant strains (67 microstrains) were observed when forces simulating conventional complete dentures were applied on the models and the highest peri-implant strains (9091 microstrains) were observed when forces simulating parafunctional habit were applied. One-way ANOVA test followed by Tukey's post hoc analysis was performed to compare the mean deformation scores between different materials at 50 N load. The level of significance [P-value] was set at P < 0.05. Tests showed significant differences between zero mm and the other types in all the different materials, and also between 1.5 x AP and 2.5 x AP for Zirconia and Peek material at P = 0.02 & P = .008, respectively. The results showed that the type of framework material, cantilever length, and occlusal forces from the opposing arch influence the peri-implant strain in the bone in all-on-four implant-supported prostheses. CONCLUSION: Rehabilitation of a single, completely edentulous arch with implant-supported prostheses should consider the situation of the opposing arch. The choice of framework material, as well as the cantilever length, should be altered based on the forces from the opposing arch.

Optical-vortex diagnostics via Fraunhofer slit diffraction with controllable wavefront curvature.

Far-field slit diffraction of circular optical-vortex (OV) beams is efficient for measurement of the topological charge (TC) magnitude but does not reveal its sign. We show that this is because in the common diffraction schemes the diffraction plane coincides with the incident OV waist plane. Based on the examples of Laguerre-Gaussian incident beams containing a spherical wavefront component, we demonstrate that the far-field diffracted beam profile possesses an asymmetry depending on the incident wavefront curvature and the TC sign. This finding enables simple and efficient ways for the simultaneous diagnostics of the TC magnitude and sign, which can be useful in many OV applications, including OV-assisted metrology and information processing.

Experimental infection and pathology of two highly pathogenic avian influenza H5N1 viruses isolated from crow and chicken in house crows (Corvus splendens).

We investigated the experimental infection of two highly pathogenic avian influenza H5N1 viruses isolated from crow (A/crow/Assam/142119/2008) and chicken (A/chicken/Sikkim/151466/2009) in house crows (Corvus splendens). Both viruses caused infection in crows, where four out of six and three out of six crows succumbed to H5N1 infection within 11 days post challenge by crow and chicken viruses, respectively. The major clinical signs in crows were wing paralysis, circling and torticollis. The virus shedding detected from swabs was not persistent in both crow nor chicken viruses. Both viruses were isolated more frequently from oral swabs than from cloacal swabs. Both virus strains were isolated from brain, lungs, heart, liver, pancreas, spleen, large intestines of crows that succumbed to H5N1 infection. The surviving birds seroconverted in response to H5N1 virus infection. Microscopically, both viruses caused coagulative necrosis in pancreas and kidneys. Brain showed gliosis and neuronal degeneration. This experimental study highlights that crows could be infected with H5N1 viruses from different hosts with minor differences in pathogenicity. Therefore, it is imperative to carry out surveillance of highly pathogenic avian influenza H5N1 virus in synanthropic birds along with biosecurity measures to mitigate the H5N1 spread in poultry population. Keywords: chicken virus; crow virus; highly pathogenic avian influenza; house crows.