Objective: We tested the hypothesis that inducible nitric oxide synthase (iNOS) modulates angiogenesis in human models and this information could be extrapolated in elucidating the pathophysiology of oral submucous fibrosis (OSF). A hypothesis which looks inadequate, but is deep rooted in literature is the epithelial alteration ("atrophy") seen in OSF and the events that lead to its causation. This aspect was tried to be addressed and an alternative pathogenetic pathway for the disease is proposed. Materials and Methods: This immunohistochemical study sought to investigate the expression of iNOS in OSF samples (n= 30) a using monospecific antibody (SC- 2050, Santa Cruz Biotechnology, Inc) to the protein and also to correlate it with different grades of epithelial dysplasia associated with the disease. Twenty (20) healthy adults acted as controls. Results: iNOS staining was not demonstrated in normal oral epithelium. In oral epithelial dysplasia, staining was seen in all cases (100%) in the basal layers of the epithelium and in 30% of cases it extended into the parabasal compartments as well. iNOS staining was uniformly positive in moderate dysplasia with an increase in intensity and distribution noted as the severity of dysplasia progressed. There were highly significant differences in overall positivity for iNOS in epithelium between cases and controls (Mann-Whitney U = 11.000, Wilcoxon W = 221.00, P = 0.000). Significant comparisons were made of mild Vs moderate dysplasia (Mann-Whitney U = 48.000, P = 0.014) Conclusions: This study supports our earlier morphological assessment (image analysis) of the nature of vascularity in OSF mucosa. The significant vasodilation noticed in these cases argues against the concept of ischemic atrophy of the epithelium. This observation of vascularity and iNOS expression helped to explain the vasodilation noticed (sinusoids) in this disease; NO being a net vasodilator. The mechanism of activation of iNOS in dysplasia is difficult to explain. The role of contingent paracrine-activating factors on keratinocytes and macrophages is discussed.

Mitosis of cells gives rise to tissue integrity. Defects during mitosis bring about abnormalities. Excessive proliferation of cells due to increased mitosis is one such outcome, which is the hallmark in precancer and cancer. The localization of proliferating cells or their precursors may not be obvious and easy. Establishing an easy way to distinguish these mitotic cells will help in grading and understanding their biological potential. Although immunohistochemistry is an advanced method in use, the cost and time factor makes it less feasible for many laboratories. Selective histochemical stains like toluidine blue, giemsa and crystal violet have been used in tissues including the developing brain, neural tissue and skin. Aim of the study: 1) To compare the staining of mitotic cells in haematoxylin and eosin with that in crystal violet. 2) To compare the number of mitotic figures present in normal oral mucosa, epithelial dysplasia and oral squamous cell carcinoma in crystal violet-stained sections with that in H and E-stained sections. Materials and Methods: Ten tissues of normal oral mucosa and 15 tissues each of oral epithelial dysplasia seen in tobacco-associated leukoplakia and squamous cell carcinoma were studied to evaluate the selectivity of 1% crystal violet for mitotic figures. The staining was compared with standard H and E staining. Statistical analysis was done using Man-Whitney U test. Results: A statistically significant increase in the mean mitotic count was observed in crystal violet-stained sections of epithelial dysplasia as compared to the H and E-stained sections ( p = 0.0327). A similar increase in the mitotic counts was noted in crystal violet-stained sections of oral squamous cell carcinoma as compared to the H and E-stained sections.( p = 0.0443). No significant difference was found in the mitotic counts determined in dysplasia or carcinoma by either the crystal violet ( p = 0.4429) or the H and E-staining techniques ( p = 0.2717). Conclusion: One per cent crystal violet provides a definite advantage over the H and E-stained sections in selectively staining the mitotic figures.

Background: Oral submucous fibrosis (OSF) is a precancerous condition associated with the use of areca nut in various forms. There are very few reports to correlate the clinical stage to histopathological grading in OSF. Materials and Methods: A hospital-based study was conducted on 75 OSF cases who visited our hospital in Chennai from 2000-2003. A detailed history of each patient was recorded along with a clinical examination. Biopsy was performed for histopathological correlation. Clinical stage of the disease in terms of the ability to open one's mouth was correlated with histopathological grading. Results: The male to female ratio of OSF cases was 6:1. All forms of areca nut products were associated with OSF. Chewing of paanmasala was associated with early presentation of OSF as compared to chewing of the betel nut. Out of 57 cases, which were in clinical stage II, 91.2% had histological grading of I and II in equal proportions and 8.8% had histological grade III. Out of 13 cases that showed a clinical stage of III, 52% showed a histological grade of II, 40% grade III and 8% grade I. Conclusion: In the present study, there was no direct correlation between clinical stages and histopathological grading. The possibility of difference in the severity and extent of fibrosis in different regions of the oral mucosa and involved muscles were considered as contributory factors for this variation.

This article of the series Dentistry and Ayurveda describes in brief, the basic principlesand unique concepts involved in Ayurveda namely the concepts of Ama, Ojas, Rasas (tastes-types and the factors affecting the choice of the drug / medicine etc.), immunity, etiopathogenesis and prevention of diseases in Ayurveda in general.

A potential approach to the treatment of genetic disorders is gene therapy. The goal of gene therapy is to introduce therapeutic genetic material into the target cell to exert the intended therapeutic effect. Gene therapy has already shown promising results for the treatment of monogenic disorders such as severe combined immunodeficiency and haemophilia. Now the procedure has been extended to the level of treating malignant conditions such as cancer of the lungs, breast, colon etc. The prevalence of tumours of the larynx and oral cavity has increased in both developed and developing countries. This increase underscores the need for a novel therapeutic modality that would decrease or completely terminate the proliferation of malignant cells. This review highlights various types of gene therapy procedures with respect to oral squamous cell carcinoma.

Code of practice is dangerous and ever-changing in today's world. Relating this to complete denture impression technique, we have been provided with a set of philosophies - "no pressure, minimal pressure, definite pressure and selective pressure". The objectives and principles of impression-making have been clearly defined. Do you think any philosophy can satisfy any operator to work on these principles and achieve these objectives? These philosophies take into consideration only the tissue part and not the complete basal seat, which comprises the periphery, the tissues and the bone structure. Under such circumstances, should we consider a code of practice dangerous or should we develop an evidence-based approach having a scientific background following certain principles, providing the flexibility to adapt to clinical procedures and to normal biological variations in patients rather than the rigidity imposed by strict laws?

We present a case of unicystic ameloblastoma of the posterior mandible in a 28 year-old female, histologically showing luminal and intramural plexiform epithelial proliferation with typical dentin in the connective tissue capsule. The characteristics of hard tissue formation in ameloblastomas reported in existing literature and the possible origin of the dentin mass seen in our case are discussed.

Botryomycosis arises from chronic infections produced by low-virulence organisms in an altered host environment. Staphylococci have been the most common organisms implicated, but various other bacteria have also been identified in human botryomycosis lesions. The relative balance between the host's resistance and the microorganism's virulence may be altered in some way that perpetuates the growth of the lesions in a symbiotic fashion. The diagnosis of botryomycosis is one that is often easily overlooked because it can be confused with other mycetomas such as actinomycosis and nocardosis. We report here a case of micrococcal botryomycosis that occurred in the left temporal region in a 70 year-old male, which was diagnosed by the help of a histopathological examination and microbial cultures.

Denture-induced fibrous hyperplasia (DIFH) is a persistent lesion caused mostly by the prolonged wear of an ill-fitting, over-extended denture. Although the condition frequently coexists with denture stomatitis, it is a distinct entity with a different protocol for management. The article describes successful treatment for a case of DIFH using carbon dioxide laser and a two year follow-up. The inherent advantages of using carbon dioxide laser over conventional surgical techniques are discussed.

Supernumerary teeth are a relatively frequent disorder of odontogenesis characterized by an excess number of teeth. Mesiodens is the most common type of supernumerary tooth found in the premaxilla between the two central incisors. They can be supplemental (resembling natural teeth), conical, tuberculate or molariform. We present the case of a 19 year-old girl who presented with a mesiodens of an unusual morphology and multiple impacted supernumerary teeth not associated with any syndrome.

Ectopic eruption of teeth into a region other than the oral cavity is rare although there have been reports of teeth in the nasal septum, mandibular condyle, coronoid process, palate, chin and maxillary sinus. Occasionally, a tooth may erupt in the maxillary sinus and present with local sinonasal symptoms attributed to chronic sinusitis. We present a case of an ectopic maxillary third molar tooth that caused chronic purulent sinusitis in relation to the right maxillary sinus.