Histomorphometric analysis of nuclear and cellular volumetric alterations in oral lichen planus, lichenoid lesions and normal oral mucosa using image analysis software.

Introduction: Lichen planus is a chronic inflammatory mucocutaneous disease that clinically and histologically resembles lichenoid lesions, although the latter has a different etiology. Though criteria have been suggested for differentiating oral lichen planus from lichenoid lesions, confusion still prevails. Aims: To study the cellular and nuclear volumetric features in the epithelium of normal mucosa, lichen planus, and lichenoid lesions to determine variations if any. Materials and Methods: A retrospective study was done on 25 histologically diagnosed cases each of oral lichen planus, oral lichenoid lesions, and normal oral mucosa. Cellular and nuclear morphometric measurements were assessed on hematoxylin and eosin sections using image analysis software. Statistical Analysis: Analysis of variance test (ANOVA) and Tukey's post-hoc test. Results: The basal cells of oral lichen planus showed a significant increase in the mean nuclear and cellular areas, and in nuclear volume; there was a significant decrease in the nuclear-cytoplasmic ratio as compared to normal mucosa. The suprabasal cells showed a significant increase in nuclear and cellular areas, nuclear diameter, and nuclear and cellular volumes as compared to normal mucosa. The basal cells of oral lichenoid lesions showed significant difference in the mean cellular area and the mean nuclear-cytoplasmic ratio as compared to normal mucosa, whereas the suprabasal cells differed significantly from normal mucosa in the mean nuclear area and the nuclear and cellular volumes. Conclusions: Morphometry can differentiate lesions of oral lichen planus and oral lichenoid lesions from normal oral mucosa. Thus, morphometry may serve to discriminate between normal and premalignant lichen planus and lichenoid lesions. These lesions might have a high risk for malignant transformation and may behave in a similar manner with respect to malignant transformation.

Oral lichenoid lesions: Clinico-pathological mimicry and its diagnostic implications.

Oral cavity is commonly affected by number of lichenoid lesions, whose clinical and histopathologic features overlap due to the presence of inflammatory cells in connective tissue. Segregation of these lichenoid lesions is mandatory as each may embody a distinct disease entity in terms of cause, diagnosis and prognosis. The literature discussed in the article is an attempt to segregate individual lichenoid lesions by defining clinical and histopathologic variations among each other, which avoids the diagnostic problem.

Perlecan (basement membrane heparan sulfate proteoglycan) and its role in oral malignancies: An overview.

Perlecan means pearl-like structures. Perlecan is a large proteoglycan (400-500 kDa) present in virtually all vascularized tissues with a distribution that is primarily confined to basement membranes including those of oral mucosa. It is a basement membrane-type heparan sulfate proteoglycan. Perlecan is synthesized by basal cells and fibroblasts adjacent to the basal lamina . Perlecan is also synthesized by vascular endothelial and smooth muscle cells present in the extracellular matrix. It has been demonstrated in recent years that perlecan is distributed in the stromal space of various pathophysiological conditions. The complex pleiotropy of perlecan suggests that this gene product is involved in several developmental processes, at both early and late stages of embryogenesis, as well as in cancer and diabetes. In the oral cavity, perlecan expression is reported to basal cells in normal mucosa and its expression increases in precancer and cancerous conditions. It is also expressed in various odontogenic tumors such as ameloblastoma, keratocyst odontogenic tumor, and also salivary gland tumors such as adenoid cystic carcinoma, mucoepidermoid carcinoma, etc.

Histopathologic changes in soft tissue associated with radiographically normal impacted third molars.

Background: The incidence of impacted or embedded third molars accounts for approximately 98%. Since 1948, there are studies reporting pathological changes in an asymptomatic dental follicle. Controversy still exists for removal of asmptomatic impacted teeth. Hence, this study was performed to histologically evaluate soft tissue pathosis in the pericoronal tissues of impacted third molars with pericoronal radiolucency measuring up to 2.5 mm on orthopantomographs. Materials and Methods: Forty-one asymptomatic impacted third molars with follicular space of up to 2.5 mm on radiographs were included. The disimpacted teeth and the follicular tissues were obtained for histological examination. Results: Age of the patients ranged from 14 to 25 years. Of 41 tissues evaluated, histopathological reports of 18 follicles were suggestive of dentigerous cyst, two follicles showed odontogenic keratocyst, one follicle each of calcifying epithelial odontogenic cyst, ameloblastoma-like proliferation, odontogenic myxoma and odontogenic fibroma. Conclusion: This study showed 58.5% of asymptomatic cases with definite pathological changes. Hence, thorough clinical and radiographic examination should be carried out for all impacted third molars and the dental follicular tissue should be submitted for histopathological evaluation.

Informed consent: a survey of general dental practitioners in Belgaum city.

The informed consent process allows the patient or legal guardian to participate in and retain autonomy over the medical service received. Obtaining informed consent may also decrease the practitioner’s liability from claims associated with miscommunication. The aim of this study was to assess knowledge and practices of general dental practitioners (GDPs) regarding informed consent. 118 GDPs in Belgaum city, Karnataka, India, were given questionnaires asking for information on their knowledge and practices related to informed consent. The questions covered general information, treatment-specific issues and the consent process. 80 responses were received out of which 44 were complete. 63.6% of GDPs reported that they obtained written consent. All of them reported that they obtained only general consent. 4 of them obtained written consent in the local language. 37 said they gave a detailed explanation of the procedure. 3 said they did not inform their patients on radiation exposure. Dentists should upgrade their knowledge regarding legal jurisprudence and legal medicine to avoid any litigation.

Comparison of staining of mitotic figures by haematoxylin and eosin-and crystal violet stains, in oral epithelial dysplasia and squamous cell carcinoma.

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 Mann-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.