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We report a transformative epoxy system with a microalgae-derived bio-binder from hydrothermal liquefaction processing (HTL). The obtained bio-binder not only served as a curing agent for conventional epoxy resin (e.g., EPON 862), but also acted as a modifying agent to enhance the thermal and mechanical properties of the conventional epoxy resin. This game-changing epoxy/bio-binder system outperformed the conventional epoxy/hardener system in thermal stability and mechanical properties. Compared to the commercial EPON 862/EPIKURE W epoxy product, our epoxy/bio-binder system (35 wt.% bio-binder addition with respect to the epoxy) increased the temperature of 60% weight loss from 394 °C to 428 °C and the temperature of maximum decomposition rate from 382 °C to 413 °C, while the tensile, flexural, and impact performance of the cured epoxy improved in all cases by up to 64%. Our research could significantly impact the USD 38.2 billion global market of the epoxy-related industry by not only providing better thermal and mechanical performance of epoxy-based composite materials, but also simultaneously reducing the carbon footprint from the epoxy industry and relieving waste epoxy pollution.

Background: Occupational hazards are common among dental professionals, and musculoskeletal disorders (MSDs) are very common. Aim: The aim is to report the prevalence and distribution of MSD among dental professionals practicing in Nagpur, India. Materials and Methods: A cross-sectional questionnaire study was conducted among 500 dental professionals from December 2016 to November 2017. The professionals were distributed in three groups (Group A, B, and C) based on the work experience in years. The questionnaire was designed to evaluate physical health related to MSD. Statistical analysis was performed by descriptive and inferential statistics using SPSS 17.0 version (Chicago, USA) software and the data were presented in counts and percentages, with P ≤ 0.05 is considered as the level of statistical significance. Results: In Group A, 24% of participants suffered pain in lower back while 4% of participants suffered from pain in multiple regions. In Group B, 27% of participants suffered pain in lower back whereas 5% experienced pain in multiple regions. In Group C, 34% of participants suffered pain in lower back whereas 17% experienced pain in multiple regions. The most common specific disorder among dental professionals was tendonitis of the shoulder and repetitive strain injury. There was an increasing trend in the presence of neurological pain with increase in number of years in dental practice. Conclusions: The musculoskeletal region most frequently affected in all three groups was lower and upper back contributing about 40% regions affected. However, there was no pain recorded among 32% in dental professionals. Pain involving the body parts depends on the posture, time, and procedures. Dental professionals always need to maintain multiple postures for prolonged periods; therefore, dental procedures should be divided into multiple appointments to minimize the time-consuming procedures. A daily routine should be followed with exercise or yoga for strain-free muscular activities.

The consequence of relative age eff ect (RAE) has been an overrepresentation of athletes born early in the cohort and an underrepresentation of athletes born late in the cohort. There are signifi cantly fewer studies that examine this phenomenon among female soccer players. Therefore, the purpose was to determine the existence of RAEs among elite youth female soccer players competing in the Elite Clubs National League (ECNL) during the 2012-2013 season. Player birthdates (U14-U18 N=7,294) were collected from the ECNL and compared to the birthdates distribution for the general population. Data revealed a RAE across all age groups (U14-U18) indicating a preference for the selection of the oldest in the cohort. An overrepresentation of players was observed in Q1 and an underrepresentation of players in Q4 among the U14-U17 age groups. Among the u18 age group, an overrepresentation of players was detected in Q2 and an underrepresentation of players in Q4. The birthdate distribution for the fi rst and second halves of the playing season showed strong RAEs among the U14-U17 age groups. No statistically signifi cant diff erence was found between the fi rst and second halves of the playing season among players in the U18 age group.

Crouzon's syndrome is a rare genetic disorder characterized by distinctive craniofacial malformations. The disease is characterized by premature synostosis of coronal and sagittal sutures which begins in the 1st year of life. Herein, we report a case of this rare entity, a 12-year-old girl with Crouzon's syndrome, who displayed dysmorphic skull and facial features such as craniosynostosis, hypertelorism, exophthalmia, external strabismus, short upper lip, midfacial hypoplasia with a hypoplastic maxilla, and relative mandibular prognathism. The dentist can play an integral role in the multidisciplinary treatment the patients require. The genetic advising and an individual study of each case are essential to promote the improvement of the diagnosis. An early multidisciplinary approach is necessary, with specific therapeutic program aiming at the prevention of late diagnosis effects.

Pycnodysostosis is an uncommon autosomal recessive sclerosing bone disorder which is characterized by short stature and generalized diffuse osteosclerosis. Patients usually have a large head with separated sutures, open fontanels, aplasia of frontal sinuses, obtuse mandibular gonial angle, and acroosteolysis of the distal phalanges. This case report showed a 25-year-old female with features pathognomonic of pycnodysostosis. The emphasis is mainly on the early diagnosis as it has an important role in the general health of such patients and prevention of complications.

It can be extremely challenging to diagnose systemic disorders through their oral manifestations. Sometimes, these oral findings can be the only manifestation for years, logically improving the prognosis if identified at an early stage. This case report is about a female patient who had been under medical treatment for a wide range of oral and systemic symptoms including recurrent parotid abscess, which were being treated individually without ascertaining the probable underlying cause. Based on a positive history and clinical evaluation for ocular and oral dryness, sialography, and minor salivary gland biopsy was performed which revealed sialectasis. A diagnosis of Sjögren's syndrome was arrived at and the patient underwent further workup to determine any potential associated disorders. Skin biopsy and serology indicated systemic sclerosis with lung involvement. The patient received intravenous pulse methylprednisolone therapy and symptomatic treatment for oroocular dryness. Apart from systemic antibiotics for management of recurrent parotid abscess, a novel approach consisting of retrograde irrigation of salivary glands with intravenous metronidazole and amoxicillin was performed at regular intervals. This case report also revisits and reintroduces sialography for glandular pathologies. Although over the years, many new imaging techniques have superseded this procedure, it still remains the one procedure that can be easily performed within the confines of the most basic dental setup.

Dystrophic calcinosis is a condition wherein calcium is deposited in degenerated tissues, often associated with trauma, infection, or inflammation, in the absence of a systemic mineral imbalance. It commonly occurs in cardiac and skeletal muscles; rarely in oral and perioral region. We report a unique case of a 25-year-old healthy male, with dystrophic calcinosis in the subcutaneous tissues of the cheek overlying the right body of the mandible, with history of infection in that region. CT and CBCT examination revealed multiple irregular to curvi-linear shaped radiodense calcified structures, discrete from the mandibular buccal cortex. The calcified structures were surgically removed via extra oral approach without complications. Although soft tissues of the cheek do not frequently contain lesions that include calcifications, dystrophic calcinosis must be considered among the differentials for calcified masses in the oral region, particularly when infection is present. Its preoperative diagnosis poses a challenge in view of differential diagnosis.

Ameloblastomas are tumors of odontogenic epithelial origin. The term unicystic ameloblastoma is used to describe cystic lesions with clinico-radiographic features resembling an odontogenic cyst, but histologically showing the presence of ame-loblastomatous epithelium lining part of the cyst cavity. A large majority of lesions are found in the mandible, and usually cause a painless swelling of the jaws. They can be radiographically subdivided into 'dentigerous' and 'non-dentigerous' types. The unicystic ameloblastoma is believed to be less aggressive than a solid/multicystic ameloblastoma, and thus has a more favorable response to enucleation and curettage. This case report presents a case of unicystic ameloblastoma with a multilocular radiographic appearance in the anterior mandible of a 45-year-old female patient, along with a literature review of the topic.

The calcifying epithelial odontogenic cyst (CEOC) is a developmental odontogenic cyst, which was first categorized as a distinct entity by Gorlin in 1962. It is an unusual and unique lesion, which may show characteristics of both a solid neoplasm and a cyst. It usually occurs as an intra-osseous lesion but may occasionally occur as an extra-osseous or peripheral variant. It shows a nearly equal distribution between the maxilla and mandible and is commonly seen anterior to the first molar. The clinical and radiographic features of this lesion are not pathognomonic, and it is characterized by its histological diversity, with the most characteristic feature being the presence of a variable number of ghost cells within the epithelial component. Treatment is conservative with surgical enucleation, and recurrences are rare. This report describes a case of CEOC in association with an impacted mandibular first premolar, which was diagnosed in a 13-year-old female patient, along with a review of the literature.

Objectives: The purpose of this case series was to compare the clinical, radiographic, and histopathologic features of 11 cases of ameloblastoma that reported to the Goa Dental College and Hospital over a period of 4 years from January 2008 to December 2012. Study Design: Data with respect to the patients′ ages, sex, location of lesions, radiographic features, histopathologic features and surgical treatment and follow-up, was analyzed. Results: The mean age in males was 23.25 ± 6.99 years, while that in females was 43.43 ± 17.13 years. Seven (63.63%) of the 11 subjects were females, and four (36.36%) were males. 10 (90.9%) of the 11 ameloblastomas were located in the mandible. Swelling was noted in all 11 patients. 10 cases showed radiographic findings, while one case was a peripheral soft-tissue variant. Seven (70%) of the 10 tumors were multilocular with a well-demarcated corticated border, and three cases (30%) were unilocular. Two cases showed a soap-bubble appearance. Histologically, five cases were unicystic, four were multicystic, one was desmoplastic and one was a peripheral variant. Follow-up ranged from 12 to 34 months and there were no signs of recurrence in any of the patients. Conclusions: Ameloblastomas more commonly occur in females at an older age, as compared with males. Radiographic features that could help in diagnosing ameloblastomas include its predominant occurrence in the mandible, multilocular radiolucency with well-defined, corticated, scalloped margins, expansion of buccal and lingual cortical plates, root resorption and tooth displacement.

Introduction: Oral Submucous Fibrosis (OSMF) is a premalignant condition with potential malignant behaviour characterized by juxta-epithelial fibrosis of the oral cavity. In the process of collagen synthesis, iron gets utilized, by the hydroxylation of proline and lysine, leading to decreased serum iron levels. The trace element like iron is receiving much attention in the detection of oral cancer and precancerous condition like OSMF as it was found to be significantly altered in these conditions. Aim: The aim of this study was to compare the haemoglobin and serum iron values of OSMF subjects with that of iron deficiency anaemia subjects. Materials and Methods: Total of 120 subjects were included, 40 subjects with the OSMF, 40 with the iron deficiency anemia without tobacco chewing habit, 40 healthy control subjects without OSMF and iron deficiency anaemia. A total of 5ml of venous blood was withdrawn from all the subjects and serum iron and haemoglobin levels were estimated for all the subjects. Estimation of iron was done using Ferrozine method and haemoglobin by Sahli’s method. The statistical method applied were Kruskal Wallis, Mann Whitney and Pearson correlation coefficient test. Results: There was a statistically significant difference in serum iron and haemoglobin level in all three groups (p

Aims and Background: Teeth form an excellent material for anthropological, genetic, odontologic and forensic investigations. The aim of this study was to establish the genetic control of sexual dimorphism in tooth size amongst siblings of Goan children in age range of 14-22 years. Materials and Methods: Twenty-two sibling pairs were selected (22 males and 22 females) to assess genetic control of sexual dimorphism in tooth size. Alginate impressions were obtained for maxillary and mandibular arches and study models were prepared. Measurements were done using Zoom Digimatic Vernier Calipers with a resolution of 0.01 mm. Statistical Analysis: Correlation between mesiodistal and buccolingual tooth sizes amongst siblings was calculated using Pearson’s correlation coefficient. Results: A statistically significant association was found between Mesiodistal Widths of Permanent Maxillary Right and Left Second Molars and between Maxillary Right and Left First Premolars amongst sibling pairs. A statistically significant association was also found between Buccolingual Widths of Mandibular Right and Left First Premolars amongst sibling pairs. This statistically significant correlation found amongst siblings establishes a genetic control over sexual dimorphism in these teeth. Conclusion: The genetic basis of sexual dimorphism in human dentition was ascertained as a significant correlation was found between mesio-distal and bucco-lingual widths of premolars between sibling pairs.

Squamous cell carcinoma (SCC) arising from odontogenic cyst lining is rare. The exact incidence of carcinoma arising in odontogenic cyst is unknown, but it is estimated to vary between 1 and 2/1000. The pathogenesis is unknown, but a long-standing inflammation and continuous intracystic pressure have been suggested as possible causative factors. Metastasis from these lesions is not common (< 20%), and most of the carcinomas are moderately to well differentiated. To qualify as a primary intraosseous carcinoma, there must be no initial connection with the oral mucosa, overlying skin, or antral or nasal mucosa. This paper presents a case of primary intraosseous carcinoma arising from odontogenic keratocyst in the anterior mandible with metastasis to left parotid lymph nodes.

Myxosarcoma is a rare malignant neoplasm of connective tissue which is characterized by tissue that resembles primitive mesenchyme, and contains relatively undifferentiated cells that show rapid growth and invasion. The cells are stellate or spindle-shaped and are present in a loose matrix which contains mucoid material, reticulum, and collagen fibers. This paper reports a rare case of a myxosarcoma of the left maxilla in a 50-year-old male, which clinically presented as a soft-tissue mass on the buccal gingiva and radiographically showed a mixed radiolucent-radiopaque appearance.

Glanzmann′s thrombasthenia (GT) is a rare autosomal recessive disorder and characterized by a lack of platelet aggregation due to the absence of platelet glycoprotein (GP) Ilb and Illa. Usually, the disease leads to mild hemorrhage but sometimes bleeding is severe enough to be life-threatening. The site of bleeding in GT is clearly defined: purpura, epistaxis, gingival hemorrhage and menorrhagia are nearly constant features: gastrointestinal bleeding and hematuria are less common. In most cases, bleeding symptoms manifest rapidly after birth, even if GT is occasionally only diagnosed in later life. Diagnosis associates mucocutaneous bleeding with absent platelet aggregation in response to all physiologic stimuli, with normal platelet count and morphology. GT is more common in populations where marriage between blood relatives is common. Here, we present a case report of 24-year-old Indian male suffering from GT. A brief review of the relevant literature is also presented.

In the present study experimental and numerical investigations were carried out to predict the low velocity impact response of four symmetric configurations: 10 ply E Glass, 10 ply AS4 Carbon, and two Hybrid combinations with 1 and 2 outer plies of E Glass and 8 and 6 inner plies of Carbon. All numerical investigations were performed using commercial finite element software, LS-DYNA. The test coupons were manufactured using the low cost Heated Vacuum Assisted Resin Transfer Molding (H-VARTM©) technique. Low velocity impact testing was carried out using an Instron Dynatup 8250 impact testing machine. Standard 6 × 6 Boeing fixture was used for all impact experiments. Impact experiments were performed over progressive damage, that is, from incipient damage till complete failure of the laminate in six successive impact energy levels for each configuration. The simulation results for the impact loading were compared with the experimental results. For both nonhybrid configurations, it was observed that the simulated results were in good agreement with the experimental results, whereas, for hybrid configurations, the simulated impact response was softer than the experimental response. Maximum impact load carrying capacity was also compared for all four configurations based on their areal density. It was observed that Hybrid262 configuration has superior impact load to areal density ratio.

Response of fiberglass epoxy composite laminates under low velocity impact loading is investigated using LS-DYNA®, and the results are compared with experimental analysis performed using an instrumented impact test setup (Instron dynatup 8250). The composite laminates are manufactured using H-VARTM© process with basket weave E-Glass fabrics. Epon 862 is used as a resin system and Epicure-W as a hardening agent. Composite laminates, with 10 layers of fiberglass fabrics, are modeled using 3D solid elements in a mosaic fashion to represent basket weave pattern. Mechanical properties are calculated by using classical micromechanical theory and assigned to the elements using ORTHOTROPIC ELASTIC material model. The damage occurred since increasing impact energy is incorporated using ADVANCED COMPOSITE DAMAGE material model in LS-DYNA®. Good agreements are obtained with the failure damage results in LS-DYNA® and experimental results. Main considerations for comparison are given to the impact load carrying capacity and the amount of impact energy absorbed by the laminates.

We report a transformative epoxy system with a microalgae-derived bio-binder from hydrothermal liquefaction processing (HTL). The obtained bio-binder not only served as a curing agent for conventional epoxy resin (e.g., EPON 862), but also acted as a modifying agent to enhance the thermal and mechanical properties of the conventional epoxy resin. This game-changing epoxy/bio-binder system outperformed the conventional epoxy/hardener system in thermal stability and mechanical properties. Compared to the commercial EPON 862/EPIKURE W epoxy product, our epoxy/bio-binder system (35 wt.% bio-binder addition with respect to the epoxy) increased the temperature of 60% weight loss from 394 °C to 428 °C and the temperature of maximum decomposition rate from 382 °C to 413 °C, while the tensile, flexural, and impact performance of the cured epoxy improved in all cases by up to 64%. Our research could significantly impact the USD 38.2 billion global market of the epoxy-related industry by not only providing better thermal and mechanical performance of epoxy-based composite materials, but also simultaneously reducing the carbon footprint from the epoxy industry and relieving waste epoxy pollution. [ABSTRACT FROM AUTHOR]