The presence of micronuclei (MN) in mammalian cells is related to several mutagenetic stresses. MN are formed as a result of chromosome damage and can be readily identified in exfoliated epithelial cells. MN is chromatin particles derived from acentric chromosomal fragments, which are not incorporated into the daughter nucleus after mitosis. It can be visualized by chromatin stains. A variety of factors influences the formation of MN in cells such as age, sex, genetic constitution, physical and chemical agents, adverse habits such as tobacco, areca nut chewing, smoking, and alcohol consumption. Micronucleation has important implications in the genomic plasticity of tumor cells. The present paper reviews the origin, fate and scoring criteria of MN that serves as a biomarker of exposure to genetic toxins, and for the risk of cancer.

Background:The overall success of dental implants depends on the crestal bone support around the implants. During the initial years of dental implant placement, the bone loss around the implants determines the success rate of treatment. Platform switching (PLS) concept preserves the crestal bone loss, and this approach should be applied clinically for the overall success of dental implants.Purpose:The purpose of this study is to discuss the literature dealing with the concept of PLS concept and preservation of marginal bone, the mechanism by which it contributes to maintenance of marginal bone, its clinical applications, advantages, and disadvantages, to assess its survival rates.Materials and Methods:PubMed and Google Scholar search was done to find out the studies involving PLS concept from 2005 to 2017. Data were analyzed using SPSS statistical software.Results:Literature search revealed studies involving concepts of PLS, comparison of platform-switched and nonplatform-switched implants, case reports on PLS, and studies with histological and finite element analyses regarding PLS.Conclusion:PLS helps preserve crestal bone around the implants, and this concept should be followed when clinical situations in implant placement permit.

Round cell tumors as the name suggest are comprised round cells with increased nuclear-cytoplasmic ratio. This group of tumor includes entities such as peripheral neuroectodermal tumor, rhabdomyosarcoma, synovial sarcoma, non-Hodgkin's lymphoma, neuroblastoma, hepatoblastoma, Wilms' tumor, and desmoplastic small round cell tumor. These round cells tumors are characterized by typical histological pattern, immunohistochemical, and electron microscopic features that can help in differential diagnosis. The present article describes the classification and explains the histopathology and immunohistochemistry of some important round cell tumors.

The concept of field cancerization has been ever changing since its first description by Slaughter et al in 1953. Field cancerization explains the mechanisms by which second primary tumors (SPTs) develop. SPTs are the tumors, which develop in the oral cavity in succession to the primary malignant tumors, which might vary in duration ranging from few months to years. Conceivably, a population of daughter cells with early genetic changes (without histopathology) remains in the organ, demonstrating the concept of field cancerization. This review explains the concept of field cancerization and various field theories along with molecular basis of field formation.

Aims and Objectives:To determine the association between smoking, chewing tobacco (gutka), and age of individual on graying of hair.Materials and Methods:The present study was conducted on 120 patients attending the Outpatient Department of the DJ College of Dental Sciences and Research, Modinagar, UP. The individuals were classified into four groups (group I, II, III, IV) on the basis of the form of tobacco use (smoking or chewing). The Pearson correlation coefficient was utilized to find the correlation between the mean percentage of individuals with gray hair, risk multiplication factor (RMF), and age of the individual.Results:Mean percentage of individual with gray hair and RMF (r = 0.6487) are found to be positively associated. A significant and positive correlation was observed between the age of the individual and the frequency of individuals with gray hair.Conclusion:This study suggests that there is a significant association between tobacco use and aging on graying of hair.