A Fundamental Research On The Biological Effects Of Simulating Magnetic Field Of Magnetic Attachment On Osteoblasts

Pulsed electromagnetic fields (PEMF) have been used extensively in clinical treatments of nonunited bone fractures for more than 2 decades. Static magnetic fields (SMF) are another type of electromagnetic field used in clinical practices, especially in dentistry.SMF has also been used advantageously as a 'force source' in prothodontic and orthodontic treatrmeats.There are some potential advantages for SMF. such as a power device supplied by external energy which makes SMF stimulation more suitable for long-term local healing.Recently,some studies have suggested that long-term local SMF stimulation by permanent magnets can increase the rate of bone repair and bone strength ,and prevent bone mineral density decreases caused by implantation.However, the mechanisms of effects of SMF on osteoblasts remain unclear.Objectives:The present research aimed at simulating static magnetic field of magnetic attachments,the in vitro cultured rat osteoblasts were exposed continuously to SMF for different time with three different magnetic flux density (12.5mT,125mT and 250mT).Then the effects of SMF on morphologies, microstructures, proliferations,functions,TGF-β₁ and immediate early genes c-jun were investigated, in order to research the biological effects of the SMF on osteoblasts and to guide the clinical applying of magnetic attachments. Methods:1. Cultured osteoblasts were exposed to 12.5mT,125mT,and 250mT static...