The effects of bisphosphonate administration on teeth development and growth of the jaw bones in neonatal rats (histological and immunohistochemical study)

Abstract

Background: Bisphosphonates are potent inhibitors of osteoclastic bone resorption and widely used for the treatmentof osteoporosis, and osteogenesis imperfecta in children. Clinical and experimental studies have demonstrated thatBisphosphonates delay or inhibit tooth eruption. This study tries to focus on the effect of bisphosphonate on teethdevelopment and jaw bones growth.Materials and methods: The present study includes 65 neonatal rats during lactation period from 15 Albino Wister ratsmother. Alendronate (one type of Bisphosphonates) was administrated orally (15 mg/kg) into 10 pregnant rats twotimes a week, while other 5 rats regard as control. Then the neonatal rats sacrificed in I, 6, 11, 16 and 21 days. Thelower first molar were examined histologically and immunohistochemical for amelogenin expression. Biochemicalserum analysis for calcium and alkaline phosphatase level were down for 11, 16 and 21days group. All histological,immunohistochemical, and biochemical results are compare with their controls.Results: The histological results illustrate retardation in tooth and root development, impairment in maturation ofenamel and retardation in tooth eruption of the first molar tooth germ in alendronate treated neonatal rats than theircontrols. Also immunoreactivity for amelogenin at early stages of tooth development was somewhat more intense inexperimental group than that in their controls .Moreover, calcium and alkaline phosphatase serum levels inexperimental rats are less than that of their controls.Conclusion: This study concludes that treatment with alendronate during tooth development has the potential toinhibit tooth eruption, impair tooth formation, may induce some types of dental abnormalities, and increase thebone trabecule thickness by decreasing osteoclastic activity.