Prevalence of Malocclusions among Schoolchildren from Southwestern Romania.

Malocclusions have a continuously increasing prevalence from one generation to another as a result of climate change, soil, atmosphere, and water pollution. All of these aspects have unfavorable consequences for the nutritional scheme. Thus, nutrition, together with other etiopathogenic factors, contributes to complex alterations in the somatic development of the entire organism and, implicitly, of the cephalic extremity. The study group included 4147 children from randomly selected schools from Vâlcea County, Romania. The aim of this study is to determine the prevalence of malocclusions in schoolchildren in Vâlcea County, Romania, according to the three main classes of malocclusions (according to Angle's classification), age groups (from 6 to 10 years old and from 11 to 14 years old), gender (male and female), and place of origin (rural and urban). For Angle class I malocclusions, we recorded the highest prevalence (48.78% of the total number of schoolchildren with malocclusions), followed by Angle class II malocclusions (45.85% of the total number of schoolchildren with malocclusions), and for Angle class III malocclusions we found the lowest prevalence (5.37% of the total number of schoolchildren with malocclusions). According to gender, we found the highest prevalence in the female gender (29.90% of the total number of female subjects), while in the male gender, we recorded a prevalence of 27.70% of the total number of male subjects. Regarding the place of origin, there is a higher prevalence of malocclusions in urban areas (29.16%). The study subgroup included 140 children randomly selected from the total number of subjects in the study group. They were included in a more advanced study. The aim is to find potential associations between the presence of malocclusions and various oral variables. Categorical variables were expressed as numerical values and percentages, and their association was evaluated with either the Chi-square test of association or homogeneity, or the Fisher Exact test. The acquired data were incorporated into a binomial logistic regression model to assess the likelihood of developing malocclusions in relation to the following variables: defective phonation, bruxism, frequency of teeth brushing, onychophagia, oral respiration, infantile deglutition, placing objects between the maxillaries, thumb sucking, and salivary aspects. It is also aimed at comparing the results obtained with similar ones from the specialized literature.

Comparison of apoptosis and terminal differentiation: the mammalian aging process.

Apoptosis is the ordered chain of events that lead to cell destruction. Terminal differentiation (denucleation) is the process in which cells lose their nuclei but remain functional. Our group examined cell death in three tissues using two different fixatives and a postfixation procedure, involving young (5 months) and old (2 years) guinea pigs. The data reveal that B-DNA and Z-DNA content decreases, whereas single-stranded (ss-) DNA increases, in older tissues undergoing apoptosis (skin and cornea) and terminal differentiation (ocular lens). We speculate that some of the factors that contribute to the aging process might also be responsible for the enhanced amount of damaged DNA in older tissues undergoing cell death. (J Histochem 49:929-930, 2001)