Dental implants: A boon to dentistry

The development and use of implants is one of the biggest advances in dentistry in the last few decades. It has helped to give many solutions to tooth loss as well as maxillo facial prosthetics. This article traces the history and evolution of dental implants

Ewing's sarcoma of the mandible

Ewing's sarcoma is a malignant tumor of bones that primarily affects children and young adults. The true origin of this small round cell lesion still remains controversial. It was originally described by James Ewing in 1921 as arising from undifferentiated osseous mesenchymal cells; however, recent studies suggest that Ewing's tumor might be neuroectodermally derived from various degrees of differentiation of the primitive neural tissues. This paper reports a rare case of ES of the mandible in an 11-year-old girl, which had been previously misdiagnosed and treated as a dental abscess. In the clinical examination, a hard immobile expansive mass of 2 cm diameter was observed on the left side of the mandible. Radiographic examination revealed a diffuse radiolucent lesion with ill-defined borders and wide vestibular bone plate destruction. Microscopically, the tumor was composed by monotonous small round cells that exhibited immunoreactivity for CD99, vimentin and desmin. Surgical resection of mandible followed by mandibular reconstruction was adopted. The patient was subjected to multiagent chemotherapy with Vincristine [VC], Dactinomycin [AC], Cyclophosphamide [CP] and Doxorubicin [AD])

BCL-X expression in oral cancer: Comparison between oral squamous cell carcinoma and verrucous carcinoma

Background: Verrucous carcinoma (VC) should be considered a distinct clinicopathologic entity different from the more common oral squamous cell carcinoma (OSCC) because of its unique biological behavior. Best way to understand the behavior of these carcinomas is to study them by means of molecular methods, especially in tumor progression tests and Bcl-X is an important antiapoptotic member of the Bcl-2 family and is one of the newest and most useful markers to determine the aggressiveness of many carcinomas. The relationship between this Bcl-X protein and carcinomatous behavior toward it is not studied extensively, which we attempted to evaluate using immunohistochemical analysis in selected carcinomas of the head and neck region. Method: We studied Bcl-X protein expression in sections of thirty OSCC and ten VC samples and correlated this with tumor differentiation. Results: There was a significant difference in cytoplasmic staining of Bcl-X expression with statistical analysis (P < 0.005) for VC and OSCC when compared as a group. No significance was seen among the different histological grades of OSCC and when compared with VC individually. Conclusion: The significant result between OSCC and VC suggests that their biologic course is comparable and can be helpful in differentiating them with each other for establishment of a better treatment protocol

Museums of materials used in dentistry: Our experience and literature review

There are museums in every branches of science and technologies as well as in many other fields of fine arts, sculpture, etc., serving the societies in acquisition of deeper knowledge. However, no serious attempts have been made to establish such museums in dental sciences. The aim of this article is to create awareness of the importance of the museums in the dental institutions and to provide resource for research in different specialties. The objective is to expose our unique experiences in this area which helped the students to improve their knowledge of the dental sciences and the public dental health awareness. The methods adopted were collection of large numbers of samples, fabrications of models, charts, etc., for teaching curriculum and public education and presenting them with suitable classifications. Results of this vast effort and pains taken are very much appreciated and encouraged by the visiting dentists, dignitaries, school children, and the public. Museums of dental materials should be inseparable parts of the dental teaching institutions and are very essential for the dental students and educating the societies on dental health awareness

Pyrolysis of castor oil methylesters to 10-undecenoic acid and heptaldehyde

119-128<span style="font-size:11.0pt;line-height: 115%;font-family:Calibri;mso-fareast-font-family:" times="" new="" roman";mso-bidi-font-family:="" "times="" roman";mso-ansi-language:en-us;mso-fareast-language:en-us;="" mso-bidi-language:ar-sa"="" lang="EN-US">The results of the pyrolysis of methyl esters of castor oil in a continuous tubular reactor to produce methyl undecenoate and heptaldehyde are discussed. Flow rates of esters, pyrolysis temperature and ester to steam ratios have been investigated as the process variables to arrive at the optimum values. Moreover, the literature pertaining to pyrolysis of castor oil has been reviewed.</span

Work-related musculoskeletal disorders among dental surgeons: A pilot study

Aim: To describe the work-related musculoskeletal disorders among on-job dental surgeons. Objectives: To identify the musculoskeletal disorders in terms of perception of pain and stiffness experienced by the dental surgeons due to the rigors of dental work, to determine the prevailing working environment with particular reference to dental work station in relation to musculoskeletal disorders, and to find the association between pain and stiffness experienced by the dental surgeons and the selected socio-demographic variables. Materials and Methods: The study was conducted on 30 graduated dental surgeons having a work experience of 1 year or more, post graduates and faculty members of various specialties at Yenepoya Dental College Hospital, Mangalore. The subjects were selected randomly from the hospital and they were given closed-ended questionnaire to find out perception of pain and stiffness experienced in the past 6 months. The observation of the working environment was done by walk-through observational survey. Results: The study showed that 6.6% dental surgeons always experienced shoulder pain, while 83.3% dental surgeons sometimes experienced back pain and 70% sometimes experienced neck pain. Majority of the dental surgeons (73.3%) experienced stiffness in the back and 23.3% experienced severe pain in their neck. It was observed that the number of patients attended per day by the dental surgeons had a significant association (P = 0.024) with the pain they experienced in their hip/thigh region. The frequency of pain experienced by the dental surgeons in the hip/thigh and knee joints also showed a significant association (P = 0.037) with the height of the dental surgeons. Conclusion: The study revealed that various socio-demographic variables contributed to the musculoskeletal disorders experienced by the dental surgeons. However, the number of patients attended per day by the dental surgeons vis-à-vis pain experienced in the back, wrist, and hip/thigh was significant

Comparative distribution of Lysyl Oxidase (G473A) and NQO1 (C609T) polymorphism among tea-garden workers (habitual chewers of betel quid) of Darjeeling district and Kolkata city of West Bengal

Context: Chewing of processed arecanut products with tobacco and betel quid has been attributed to many oral pathological conditions. These products are very popular among the youngsters of lower economic groups. Genetic predisposition has been now identified as a major risk factor for increasing the susceptibility toward the disease among these chewers. Aims: Our study mainly aims to find out the predisposition of LOX (G473A) and NQO1 (C609T) polymorphisms and present a comparison between the population (habitually exposed to processed arecanut and smokeless tobacco products) of a metro-city Kolkata and the tea-garden workers of Darjeeling district of West Bengal. Settings and Design: Subjects for the study was recruited from various oral health check-up camps organized in the tea-gardens of Darjeeling district and Kolkata city. Materials and Methods: Genotyping analysis was done through a Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP)-based approach. Statistical Analysis Used: A two-way contingency table analysis software (JAVASTAT: http://statpages.org/ctab2 × 2.html) using 95% confidence interval was used to study the distribution of genotypes among the populations. A P T (609) was found to be significantly higher among the north Bengal tea-garden workers [OR 0.480 (0.280-0.82) P = 0.01; 0.218 (0.091-0.524) P = 0.0001], respectively. Interestingly CT (21% in both) and TT (8% and 7%, respectively) were found to be equally distributed in the two populations. For LOX G > A (473) a significantly higher number of Kolkata individuals were found to carry the heterozygous GA allele in individuals aged <30 years [OR 3.779 (1.684-6.547) P = 0.001]. However, none were carrier of heterozygous GA allele of Kolkata population as compared with 29% north Bengal tea-garden workers aged above 31 years. Conclusions: A close observation of occurrence of oral diseases over time among such a population will be helpful to identify risk genotypes responsible for betel quid-induced oral diseases

Identification of a novel putative pancreatic stem/progenitor cell marker DCAMKL-1 in normal mouse pancreas

Stem cells are critical in maintaining adult homeostasis and have been proposed to be the origin of many solid tumors, including pancreatic cancer. Here we demonstrate the expression patterns of the putative intestinal stem cell marker DCAMKL-1 in the pancreas of uninjured C57BL/6 mice compared with other pancreatic stem/progenitor cell markers. We then determined the viability of isolated pancreatic stem/progenitor cells in isotransplantation assays following DCAMKL-1 antibody-based cell sorting. Sorted cells were grown in suspension culture and injected into the flanks of athymic nude mice. Here we report that DCAMKL-1 is expressed in the main pancreatic duct epithelia and islets, but not within acinar cells. Coexpression was observed with somatostatin, NGN3, and nestin, but not glucagon or insulin. Isolated DCAMKL-1+ cells formed spheroids in suspension culture and induced nodule formation in isotransplantation assays. Analysis of nodules demonstrated markers of early pancreatic development (PDX-1), glandular epithelium (cytokeratin-14 and Ep-CAM), and isletlike structures (somatostatin and secretin). These data taken together suggest that DCAMKL-1 is a novel putative stem/progenitor marker, can be used to isolate normal pancreatic stem/progenitors, and potentially regenerates pancreatic tissues. This may represent a novel tool for regenerative medicine and a target for anti-stem cell-based therapeutics in pancreatic cancer