Effects of Lead on the Eruption Rates of Incisor in Developing Rats

• Main Authors: Chia-Ling , Ko, 柯嘉泠
• Other Authors: Hong-Sen Chen
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/00308746658987650311

碩士 === 高雄醫學大學 === 口腔衛生科學研究所碩士班 === 96 === Project background Lead is a heavy soft metal of dull grayish color, which is usually employed in many industries. According to many research reports, the influence of lead to human body is mostly harmful. It was well known that the toxicity of lead could affect children’s intelligence quotient, cognition and behavior patterns. There are limited data in Taiwan concerning about the effects of lead through pregnant women to babies and how it would affect newborn baby’s tooth structure, eruption rates and enamel formation. Project objectives The present study was performed to describe the effects of lead exposure during test animal subject’s pregnancy and lactation stages and on the developing teeth of newborn rats. The objective of this study was to investigate the effects of lead exposure during pregnancy and lactation in the tissue and structure of newborn rat’s incisors and eruption rates of the incisor. Materials and methods This project was performed using laboratory animal models. The laboratory animals used were the outbred stock pregnant Wistar rats. They were exposed to low and high dosage lead (50ppm and 200ppm, respectively) during pregnancy and lactation. Female pregnant Wistar rats were randomly divided into five groups: group D pregnant rats were fed with low dose of lead (50ppm); group E pregnant rats were fed with high dose of lead (200ppm); group B rats in lactation were fed with low dose of lead (50ppm); group C rats in lactation were fed with high dose of lead (200ppm); group A was the control group. The newborn rat’s incisor eruption rate was then measured. Results Our data showed that the newborn which were exposed to lead during lactation stage had reduced eruption rates of incisors, particularly in high dose.In histological observation, the newborn which were exposed to lead during lactation stage had thiner odontblasts layer; the newborn which were exposed to lead during pregnant stage had irregular odontblasts layer. Conclusion In conclusion, the data had suggested the newborns exposed to lead during lactation had reduced eruption rate and were more sensitive to lead exposure.