An Investigation on DMFTand DMFS of First Permanent Molars in 12-Year- Old Blind Children in Residential Institutes for Blinds in Tehran (2000-2001)

Statement of Problem: Blindness as a disability seems to produce difficulties to reach an ideal heath status of the teeth. Moreover ordinary educational health programmes for this group of population, especially children, are not successful.Purpose: Investigate the dental health status of these children and to see if they are really different with the normal population.Materials and Methods: All sixty three 12- year- old blind children in three institutes were studied. A general questionnaire, as well as a dental questionnaire including some information on the first molars, were completed by these children.Results: The average DMFT and DMFS of the first molars were 3.30± 1.19 and 6.22±3.95 respectively. DMFT was higher in the lower molars, Compared with to the upper ones.However, DMFS was higher in the upper molars.Conclusion: The present study shows that the values of these indices, among blind children, are close to those of normal population, indicating that under controlled health condition and good education, acceptable values for DMFT and DMFS will be obtained

Effects of Adjacent Teeth on Caries Status of a Deciduous Tooth in 3-5 Years-Old Children

Introduction & Objective: Based on the carried out studies, the prevalence of dental caries in preschool children is high and ranges from 31.64 to 83.7 percents in Iran. The dmft criterion is not able to compute the impact of neighboring teeth on caries status of a tooth in deciduous teeth. The purpose of this study was to investigate the above issue in a sample of 3-5 years old children in Tehran during 2008-2009. Materials & Methods: In this cross-sectional study, a group of 400, 3–5 years old children who lived in Tehran and referred to Pediatric Dentistry Department of the Dentistry Faculty of Tehran University of Medical Sciences, Iran, for treatment of their deciduous teeth were investigated The demographic variables and mouth health cares data were collected by a questionnaire and the caries status of deciduous teeth were diagnosed by standard methods. The caries statuses were considered as spatially correlated binary data. The auto logistic regression model was implemented for inspecting the association of a tooth and its neighboring teeth which consists of two adjacent teeth and the opponent tooth. The effects of factors were tested using z-score. Results: The fitted model and the computed criteria showed that there was a strong dependency between caries statuses of a tooth and its three neighbors (including the two adjacent and the vertically opponent teeth) (p=0.0001). Also the effect of spatial auto covariate which is equivalent to the sum of statuses of nearest neighbors of a tooth is highly significant. Furthermore, the effects of local variables such as jaw and posterior-anterior positions were also highly significant (p=0.0001). Conclusions: In deciduous teeth, the three nearest neighbors have a high effect on a tooth. As a result, the teeth in maxilla and posterior locations are decayed sooner than the other ones. These findings may be considered in preventive programs of health of mouth and tooth in children

No Evidence for Association between Amelogenesis Imperfecta and Candidate Genes

"nBackground: Amelogenesis imperfecta (AI) is an inherited tooth disorder. Despite the fact that up to now, several gene muta­tions in MMP20, ENAM, AMELX and KLK4 genes have been reported to be associated with AI, many other genes sug­gested to be involved. The main objective of this study was to find the mutations in three major candidate genes including MMP20, ENAM and KLK4 responsible for AI from three Iranian families with generalized hypoplastic phenotype in all teeth. "nMethods: All exon/intron boundaries of subjected genes were amplified by polymerase chain reaction and subjected to direct sequencing."nResults: One polymorphisms was identified in KLK4 exon 2, in one family a homozygous mutation was found in the third base of codon 22 for serine (TCG>TCT), but not in other families. Although these base substitutions have been occurred in the signaling domain, they do not seem to influence the activity of KLK4 protein."nConclusion: Our results might support the further evidence for genetic heterogeneity; at least, in some AI cases are not caused by a gene in these reported candidate genes