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Background: Dental implants have been essential to the therapy of patients who are partially edentulous. Aim: Clinical evaluation of the long‑term survival and success rates of different types of implant‑supported prostheses. Materials and Methods: Patients who had a healthy edentulous ridge of three missing teeth in the posterior jaw in which two or three dental implants were placed having any of three prostheses, namely, three‑unit fixed dental prostheses (FPD) on two implants, three splinted crowns on three implants, and three splinted crowns on three implants were included. Results: The survival rate in all patients with dental implants having different types of prostheses was 94.9%. The survival rate in FPD, three splinted crowns, and three nonsplinted crowns was 100, 88.5, and 93.6% respectively. Conclusion: FPD loaded on two dental implants was found to have a greater long‑term survival rate and success rate with a lower frequency of peri‑implantitis and prosthodontic complications. [ABSTRACT FROM AUTHOR]

Introduction: The measurement of bite force is increasingly gaining importance in dentistry. This preliminary report evaluates the maximum voluntary bite force (MVBF) of young healthy individuals with normal occlusion and correlates the effect of age and gender with the maximum bite force (MBF). Materials and Methods: 405 participants in the age group of 18 to 40 years were selected from the outpatient department meeting inclusion and exclusion criteria. MVBF was measured with the help of a digital device called "Byte" at incisors, right first molar, and left first molar region. Results: There was a strong correlation between age with bite force. Bite force increased with age. Males had more bite force than females. The posterior region had higher bite force than the anterior region. Conclusion: Measurement of bite force is very important for every patient undergoing restorative treatment. The "Byte" device was found to be very efficient. [ABSTRACT FROM AUTHOR]

Background: Oral cancer is a significant global health issue, with prevention and early detection being pivotal for improved outcomes. This study investigates the impact of cultural and socioeconomic factors on oral cancer prevention behaviors, screening participation, and treatment outcomes. Materials and Methods: A cross-sectional study design was employed, involving a sample size of 1,000 participants. Participants were recruited through stratified sampling to ensure cultural and socioeconomic diversity. Statistical analyses, including logistic regression, were used to explore associations between factors and outcomes. Results: The study revealed multifaceted influences of cultural and socioeconomic factors on oral cancer-related aspects. Cultural factors significantly influenced prevention behaviors, with participants from certain cultural backgrounds exhibiting higher rates of tobacco use and lower rates of dietary adherence). Socioeconomic status played a role in screening uptake, with individuals from lower income brackets less likely to undergo regular screenings. Conclusion: Cultural and socioeconomic factors have a substantial influence on oral cancer prevention behaviors, screening participation, and treatment outcomes. [ABSTRACT FROM AUTHOR]

Background: This research study aimed to evaluate and compare the capability of four various bite registration materials to reproduce precise interocclusal relationships in the vertical dimension. Materials and Methods: Ideal maxillary and mandibular casts were mounted on the semi-adjustable articulator in maximum intercuspation after mock tooth preparation on 46, 47, and 48. Models were scanned by the Medit T500 Dental Lab Scanner, and initial reading was noted at the predetermined points. Ten interocclusal bite registrations were made using four materials (CADbite, Jet Bite, Ramitec, and Aluwax). The mandibular model was demounted and again remounted using the interocclusal records, and the final reading was noted after scanning. Results: Ramitec showed superior results when compared to polyvinyl bite registration material and Aluwax, but the differences between Ramitec, CADbite, and Jet Bite were nonsignificant. Conclusions: Although all four materials are suitable for clinical use, elastomeric materials showed superior results. In that, polyether was found to be the best. [ABSTRACT FROM AUTHOR]

Introduction: Salivary substitutes are gaining popularity these days because of the increase in patients with dry mouth. These substitutes must satisfy certain criteria to fulfill the patient's needs. One of these is wettability. Materials and Methods: One hundred fifty rectangular specimens of heat-cured denture base acrylic resin were prepared. A drop of test liquids (human saliva, distilled water, aqwet, saleva, and wet mouth) was placed over the test specimen and right and left contact angles were measured using optical contact angle machine. Results: All test liquids performed better than distilled water. Human saliva has the least contact angle followed by aqwet. Conclusion: Carboxymethyl cellulose base aqwet saliva substitute was found to be best having similar contact angle values to human saliva. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study is to investigate the effect of joint surface preparations and chemical surface treatment given to prepared surface on the transverse strength of repaired denture base resin. Methodology: Two hundred and twenty specimens (DPI India) were randomly allocated into eight groups (n = 10), according to the combination of joint surface preparation (Butt joint, 45° bevel, and rounded joint) and chemical surface treatment (methylene chloride, ethyl acetate, and methyl methacrylate) for 30 and 60 s each. Specimens, after surface treatment, were repaired with self-cured resin (DPI India) and then subjected to 3-point bending test to measure transverse strength. Fractured surfaces were viewed under stereomicroscope and subjected to AutoCAD analysis to determine type of failure (adhesive or cohesive) and measure their area. Measurement data were analyzed by one-way analysis of variance, paired t-test, Dunnett's D test, and multiple comparison Bonferroni t-test, with a 5% significance level. Results: Most of the comparisons between the test specimens were statistically significant. Specimens (methylene chloride for 60 s and rounded joint) show 60%–70% gain of strength. Conclusions: For providing better bond strength to a repaired specimen, the segment of fractured specimens to be provided "Rounded joint" preparation with etching by methylene chloride for 60 s. [ABSTRACT FROM AUTHOR]

Purpose: Acrylic denture base tends to fracture frequently during their service due to poor strength. The surface roughness of denture base is a critical property because denture base with rough surface will cause accumulation of food particles ,thereby leading plaque retention. Microbes such as candida albicans are seen inhabitating the surface. Materials and Methods: Conventional heat cure denture base reins(DPI) and heat cure denture base resin with incorporation of 15wt% aluminium oxide was studied in two groups with 20 samples each. A mold of size 65 mm × 10 mm × 3 mm (ISO Standard) was obtained by investing brass rectangles. About forty specimens were prepared. Specimens were divided into two groups (n = 20) coded A and B. Group A was the control group (n = 20) without addition of aluminum oxide. Group B was the experimental group (n = 20) with addition of 15 wt % aluminum oxide. All the specimens were stored in distilled water for 14 days. The flexural strength was measured using a three-point bending test in a universal testing machine, and the surface roughness was measured using contact-type profilometer. Results: Incorporation of 15wt% aluminum oxide leads to a significant increase in flexural strength and surface roughness of conventional heat-cure denture base resin. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study is to investigate the effect of joint surface preparations and chemical surface treatment given to prepared surface on the transverse strength of repaired denture base resin. Methodology: Two hundred and twenty specimens (DPI India) were randomly allocated into eight groups (n = 10), according to the combination of joint surface preparation (Butt joint, 45° bevel, and rounded joint) and chemical surface treatment (methylene chloride, ethyl acetate, and methyl methacrylate) for 30 and 60 s each. Specimens, after surface treatment, were repaired with self-cured resin (DPI India) and then subjected to 3-point bending test to measure transverse strength. Fractured surfaces were viewed under stereomicroscope and subjected to AutoCAD analysis to determine type of failure (adhesive or cohesive) and measure their area. Measurement data were analyzed by one-way analysis of variance, paired t-test, Dunnett's D test, and multiple comparison Bonferroni t-test, with a 5% significance level. Results: Most of the comparisons between the test specimens were statistically significant. Specimens (methylene chloride for 60 s and rounded joint) show 60%-70% gain of strength. Conclusions: For providing better bond strength to a repaired specimen, the segment of fractured specimens to be provided "Rounded joint" preparation with etching by methylene chloride for 60 s. [ABSTRACT FROM AUTHOR]

Purpose: Acrylic denture base tends to fracture frequently during their service due to poor strength. The surface roughness of denture base is a critical property because denture base with rough surface will cause accumulation of food particles, thereby leading plaque retention. Microbes such as candida albicans are seen inhabitating the surface. Materials and Methods: Conventional heat cure denture base reins(DPI) and heat cure denture base resin with incorporation of 15wt% aluminium oxide was studied in two groups with 20 samples each. A mold of size 65 mm × 10 mm × 3 mm (ISO Standard) was obtained by investing brass rectangles. About forty specimens were prepared. Specimens were divided into two groups (n = 20) coded A and B. Group A was the control group (n = 20) without addition of aluminum oxide. Group B was the experimental group (n = 20) with addition of 15 wt % aluminum oxide. All the specimens were stored in distilled water for 14 days. The flexural strength was measured using a three-point bending test in a universal testing machine, and the surface roughness was measured using contact-type profilometer. Results: Incorporation of 15wt% aluminum oxide leads to a significant increase in flexural strength and surface roughness of conventional heat-cure denture base resin. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate and compare radiographically the amount of crestal bone resorption during healing and loading period in single implant versus two implant–retained mandibular overdentures in totally edentulous patients. Materials and Methods: A total of 20 edentulous patients (12 male and 8 female) with age range of 58.6 years were included in this clinical trial which was completed in four phases (clinical and radiographic diagnosis, surgical phase, implant loading phase, and bone level measurement phase). The eligible patients were randomly allocated in two equivalent groups of 10 participants each per group. The allocation was in 1:1 ratio via randomized chit method. Group I included the case group, that is, single implant, and Group II included the control group, that is, two implants located in mandible. A total of 30 implants were placed in Group I and 20 implants in Group II. Digital intraoral peri-apical radiographs (RVG 5100) were used for measuring the bone level immediately after implant surgery, 1 month, 3 months, 4 months, and 6 months. Result: This study showed that there was a mean crestal bone loss of 0.7 mm between the tip of the implant and alveolar crest at the end of 6 months after implant placement in single implant Group I while 0.67 mm in case of Group II two-implant-retained mandibular overdentures. The percentage of crestal bone loss after 6 months follow-up was 6.45% in Group I which was statistically insignificant compared with Group II where 6.25% of bone loss was recorded. Conclusion: Single implant–retained mandibular overdentures could be used as another alternative treatment option for completely edentulous elderly patients with severely resorbed ridges and financially and systemically compromised conditions. [ABSTRACT FROM AUTHOR]

Background: This research paper aims to investigate the effectiveness of gender identification utilizing palatal rugae. Materials and Methods: The size of the sample that was selected included 100 people. They were made up of 50 men and 50 women, all in between the ages of 18 and 25. To examine their palatal rugae patterns, casts were made after taking maxillary impressions. Based on the size and rugae amount found on the left as well as the right sides, the palatal rugae patterns were investigated. Rugae patterns have been recognized based on the categorization provided by Thomas and Kotze (1983). Statistical Analysis: Chi-square analysis has been used. Results: There were comparative variations in the shape of rugae patterns among male and female individuals. The study revealed that the circular pattern was higher in males (P < 0.01) as compared to females and the unification pattern was comparatively greater in females (P < 0.05) as compared to males. The most predominant pattern that was seen in both genders was the wavy pattern that was seen to be present in 57.17% of males and 53.42% of females. The rugae number on the right and left sides did not exhibit any significant variations. Conclusions: This research thus exhibits a relevant difference in patterns of rugae and also confirms the uniqueness of patterns in each individual. Hence, it could be utilized as an adjunct to other tools for identification in the forensic sciences. [ABSTRACT FROM AUTHOR]

Introduction: A multicentric study on the benefits and outcomes of e-learning was lacking during the pandemic. This study aimed to find out the participation, satisfaction, and insights of dental and medical undergraduate learners toward digital learning during the COVID-19 pandemic in various healthcare institutes of India. Material and Methods: A questionnaire-based cross-sectional study was conducted using Google Forms online on e-learning among students from the first to the final year of MBBS and BDS courses in five healthcare institutions. Results: Most participants (72.7%) reported cellular data as their mode of internet connection. Seventy point eight percent of participants stated online classes did not affect health. Eyestrain (54.6%) was the most common, followed by headache and fatigue, whereas only 21.2% chose obesity and disturbed sleep as a consequence of e-learning. Conclusion: Most students had experience in digital learning, in which the use of smart phones with cellular data was the most common mode of digital learning during the pandemic. [ABSTRACT FROM AUTHOR]

Background: COVID-19 pandemic resulted in lockdown affecting all businesses globally. Everyone was forced to work from home (WFH) leading to challenges in productivity and motivation. Methodology: One thousand working professionals who worked from home participated in the online survey with semi-structured questionnaire using nonprobability Snowball sampling technique. Descriptive statistics was used to analyze the findings and to collect data method. Results: Participants were asked about their biggest worries during lockdown COVID-19 situation and their biggest worry was infection to COVID-19/death. Professionals were asked whether they were affected or not affected due to "WFH" in COVID situation. The questionnaire items were clubbed into six major categories of job role overload, lifestyle choices, family distraction, occupational discomfort, job performance, and distress, and majority categories were affected. Conclusion: Thus, it is observed that the increase in work commitments leads to distress among employees while distractions from family members disrupt the quality of work. While good job performance contributes to life satisfaction, distress significantly diminished it. This paves the way for more studies to be done on work–life balance under WFH arrangements for as long as the pandemic of COVID-19 is prevalent. [ABSTRACT FROM AUTHOR]

Background: COVID-19 pandemic resulted in lockdown affecting all businesses globally. Everyone was forced to work from home (WFH) leading to challenges in productivity and motivation. Methodology: One thousand working professionals who worked from home participated in the online survey with semi-structured questionnaire using nonprobability Snowball sampling technique. Descriptive statistics was used to analyze the findings and to collect data method. Results: Participants were asked about their biggest worries during lockdown COVID-19 situation and their biggest worry was infection to COVID-19/death. Professionals were asked whether they were affected or not affected due to "WFH" in COVID situation. The questionnaire items were clubbed into six major categories of job role overload, lifestyle choices, family distraction, occupational discomfort, job performance, and distress, and majority categories were affected. Conclusion: Thus, it is observed that the increase in work commitments leads to distress among employees while distractions from family members disrupt the quality of work. While good job performance contributes to life satisfaction, distress significantly diminished it. This paves the way for more studies to be done on work-life balance under WFH arrangements for as long as the pandemic of COVID-19 is prevalent. [ABSTRACT FROM AUTHOR]

The cause for failures of shafts in a conveyor pulley in iron-making unit at JSW Steel has been investigated. Visual, metallographic, chemical, and fractographic studies were carried out in this study. Fracture studies of the shaft revealed shear failure because of overload. Detailed investigation revealed that the source of overload and cause of failure to be the end disk of the pulley drum, which is not considered a critical component. The disk material complies with the required material specification but failed because of changes in metallurgical characteristics during welding. Severe centerline segregation in the end disk drastically reduced its strength and service life, leading to premature failures. It was found that end disk welding failures led to overloaded bending stresses, thereby causing an imbalance in the shaft rotation and leading to failure. [ABSTRACT FROM AUTHOR]

For better blast furnace performance, there has always been a need for better quality raw materials like sinter, lump ore, and pellets. Among these raw materials the usage of sinter in blast furnace is at higher side compared to other iron bearing materials. As the quality of sinter product improves, its usage in blast furnaces also increases. Iron ore fines are the main source for sinter making. To improve the sinter properties it is necessary to provide good quality of iron ore fines. Due to depletion of high grade iron ore resources, goethite and limonitic ore content in iron ore fines is expected to increase gradually. Usually limonitic and goethite ore are associated with higher alumina and LOI. The conventional sintering process is one of the well established processes for high quality hematite ore. It does not fully respond to the low grade iron ore associated with goethite and limonite. This has led to deterioration in sinter properties and productivity. In recent years the improvement in the quasi-particle structure with the granulation process is an effective method for improving sinter quality and productivity. To improve the sinter quality and productivity for low grade iron ore fines, different granulation processes like the conventional one, and other two advanced granulation processes like coke breeze, and flux & coke breeze coating granulation were studied in detail by conducting laboratory pot grate sintering experiments. From the test results it was found that sinter productivity, physical and metallurgical properties of the sinter improved with flux & coke breeze coating granulation process compared to conventional and coke breeze coating granulation process. Proper selection of the granulation time is very important to achieve the desired sinter properties. In the present work detailed laboratory experiments have been carried out by varying the coating time from 30s to 110s to study the influence of flux & coke breeze coating granulation time on mineralogy, productivity, physical, and metallurgical properties of sinter. With a coating granulation time of 50s, higher productivity, higher yield, and stronger sinter (higher T.I) with lower RDI and -5mm size sinter were achieved. [ABSTRACT FROM AUTHOR]

Iron ore fluxed sinter is the main ferrous burden of Jindal south west steel limited (JSWSL) blast furnaces. In sinter plant fluxes including limestone and dolomite are added to improve the sinter properties of iron ore and to provide an appropriate slag composition of the blast furnace. The raw material grain size affects the sinter process considerably because the sinter productivity and quality are strongly dependent on the green permeability of the bed, which is determined by the particle size distribution of the raw materials, the granulation effectiveness and by the sintering process itself. It is well-known that in fluxed sinter, the size of limestone affects productivity and physical and metallurgical properties of the sinter. It is therefore necessary to understand the role of limestone particle size on sinter properties and productivity. In the present work laboratory sintering experiments have been carried out with different levels of limestone mean particle size (from 0.14 to 1.83mm) to understand the influence of limestone particle size on mineralogy, productivity, physical and metallurgical properties of the sinter. Sinter productivity increased with increasing limestone mean particle size due to improved sinter bed permeability. Sinter with limestone mean particle size of 1.25 to 1.52 mm yielded better sinter strength and lower RDI compared to sinter with smaller or larger limestone mean particle size. Higher sinter strength is due to better and uniform distribution of limestone particles, and better bed permeability enabled easy assimilation and effective distribution of calcium ferrite phases. The improvement in sinter RDI is due to change in mineralogy of the sinter compared to coarser and finer limestone mean particle size. [ABSTRACT FROM AUTHOR]

The article presents a study on the impact of iron ore pellet size on its properties and microstructure. It cites that pellets properties and microstructure depend on raw material mix proportion. Also, reduction and oxidation process occur under various conditions due to pellet size differences. Pellets size from +eight to -12 mm have good strength with lower reduction degradation index (RDI) which are significantly affected by hematite, magnetite, porosity, pore density and size and slag phase.

The article presents on a study on the effect of alumina in iron ore on sinter properties and productivity in the conventional and selective granulation sintering process. The selective granulation process was used with ore fines of different alumina levels while the conventional granulation process was used with the same levels. It was revealed that increase in alumina levels also increase the pore size and number of pores in both process but the conventional pore shape become more irregular.

Mill scale is an iron oxide waste generated during steelmaking, casting and rolling. Total generation of mill scale at JSWSL is around 150 t/day and contains 60–70%FeO and 30–35%Fe2O3. To recover the iron, the mill scale must be smelted in a blast furnace or other reduction furnace; however, it is usually too fine to use without previous agglomeration such as via pellet or sinter mix. JSWSL operates a 4·2 Mtpa pellet plant to produce pellets for Corex and BF ironmaking units. The aim of this study is to determine the effect of mill scale on pellet properties. Detailed laboratory basket trials were conducted using up to 40% of mill scale in the pellet mix. The addition of mill scale up to 10% is considered to provide the optimum balance of chemical, physical and metallurgical properties of the pellet. [ABSTRACT FROM AUTHOR]

With increased usage of steel for critical applications, the demand for cleaner steel has increased. Existing technologies have been improved and new technologies are being introduced all along the process route to minimise the size and quantity of inclusions. In continuous casting, the function of tundish has changed from its early role as a liquid steel buffer to a multifunctional vessel, dominating quality adjustments, specifically inclusion flotation. To meet stringent cleanliness requirements, a methodology of forced flotation of inclusions by controlled bubbling of inert gas in tundish was developed and investigated. Location of the bubbling arrangement was optimised using the flow profile generated by water modelling experiments. Optimum gas flowrates were calculated mathematically and further adjusted with a series of experiments. Extensive plant scale trials were used to optimise the process parameters and bring the technology to practice. There was a 33–70% reduction in inclusions of size greater than 50 μm and a 13–36% reduction in inclusions 25–50 μm. Inclusion removal reduced at higher casting speeds. Under steady state conditions, efficiency of inclusion flotation was found to be a function of casting speed. Additionally, a significant reduction in oxide build-up and nozzle clogging was observed thus lengthening refractory life. [ABSTRACT FROM AUTHOR]

During induration in a straight grate machine, the green pellets pass through four different thermal treatments, namely drying, preheating, heating and cooling. The pellet bed is fired with downdraught firing leading to thermal gradients through the bed. Corex sludge, which is used as fuel in the pellet mix, supplies the necessary energy for uniform heating of the pellet. The physicochemical conditions, e.g. the temperature and oxygen partial pressure mainly depend on the amount of fuel incorporated in the pellet mix. As a result the percentage and the distribution of various phases in the pellets vary, leading to deviation in quality. To study the distribution of phases and their impact on cold crushing strength at different carbon levels (1·20 and 1·35%), pellets from different layers of the induration bed in an industrial straight grate were characterised. It was observed that the strength of the pellets varied from 142 to 268 kg/pellet and 128 to 245 kg/pellet across bed, with carbon 1·20 and 1·35% respectively. It was found that middle layer pellets had higher strength compared to top and bottom layers. It was observed that amount of hematite, magnetite, porosity and the pore size plays a significant role on the pellet strength. Pellets with 1·20% carbon showed better physical and microstructural properties across the pellet bed compared to pellets with 1·35% carbon. [ABSTRACT FROM AUTHOR]