The role of PAX9 promoter gene polymorphisms in causing hypodontia: a study in the Jordanian population

Ahmed Abu-Siniyeh,1 Omar F Khabour,1 Arwa I Owais2 1Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, Jordan; 2Department of Applied Dental Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, Jordan Background: The congenital absence of one or few teeth, hypodontia, is considered one of the utmost dental ageneses in human beings. Several genes have been shown to be involved in the development of hypodontia such as paired box gene 9 (PAX9). The expression of PAX9 is controlled by several polymorphic elements in the promoter region of the gene on 14q13.3 locus. The aim of this study was to find any association between PAX9 c.-912T>C (rs2073247) and c.-1031G>A (rs2073244) promoter polymorphisms and the development of hypodontia among the Jordanian population. Methods: Genotyping of the polymorphisms in 72 unrelated subjects with hypodontia was performed using PCR-restriction fragment length polymorphism (RFLP) technique and compared with that of 72 normal healthy unrelated control individuals. Results: The hypodontia group had a significantly higher -1031GG genotype (P<0.01) and a significantly lower -912TC genotype (P<0.01) compared with the control group. The results suggest that the transcriptional activity of PAX9 gene is affected by polymorphisms in the promoter region of this gene and is associated with hypodontia phenotype. Conclusion: The rs2073247) and rs2073244 promoter polymorphisms of PAX9 might play a role in the development of hypodontia in the Jordanian population. Keywords: PAX9, hypodontia, Jordan, polymorphism, promote

Child maltreatment: a survey of dentists in southern Brazil

Child abuse is a serious public health problem and affects the victims&#39 physical and mental health and development. The aims of this study were two-fold: to assess the attitudes and perceptions of dentists regarding child abuse, and to investigate professional characteristics associated with the identification of suspected child abuse. A questionnaire was sent to the 276 dentists of Pelotas, RS, Brazil , and 187 (68.0%) were returned. Demographic characteristics and profiles of the dentists, and information about their knowledge and attitudes regarding child abuse were collected. Descriptive analysis was performed, and associations were tested by chi-square and Fisher's exact tests. From all dentists surveyed, 123 (71.9%) reported providing treatment for children. Most dentists believed they could detect cases of child abuse (78.7%), but 85.7% had never suspected it. Among those who did suspect, 76.0% did not report the cases to authorities. No differences were observed between sexes, years of graduation, types of licenses, and the frequency at which children were treated. A higher proportion of dentists working at university had suspected child abuse. Even though dentists considered themselves able to identify suspicious cases, only a small percentage reported those suspicions, indicating a lack of awareness by these professionals in the adoption of protective measures for victims of aggression. It is necessary that dental professionals receive interdisciplinary training to enhance their ability to care for and protect children