An Animal Experimental Study On The Preservation Effect Of Anterior Tooth Sites

After tooth is extracted,the bone of edentulous loss and soft tissue atrophy,which create great difficulties for implant surgery.In order to reduce tooth extraction alveolar ridge absorption,we take site preservation techniques.Fist of all,we establish tooth extraction model of rats,we use the model to study material using in site preservation.The left mandible incisor was extracted with minimally invasive.The incisor and mandibles were scanned by micro-CT,and a digital tooth model was established by 3D DOCTOR software.The volume of incisor teeth,digital teeth model and teeth socket were calculated.The volume of digital teeth roots and teeth sockets were calculated by "filling hole" method.The real volume of incisor teeth was explored by "flotage" method.Then the date was compared to find the differences.The volume of sockets was bigger after than before extraction(p<0.05),but there were no significant differences between the length of alveolar ridge of the extracted side and untreated side(p>0.05).There were no significant differences between the volume of teeth roots and digital teeth roots model(p>0.05).Both the volume of the teeth roots and that of the digital teeth were smaller than the volume of the teeth sockets(p<0.05),so digital model was successfully established.We conducted animal experiment in the animal model.The SD rats were randomly divided into three groups,each group included eighteen SD rats,the left mandible incisor was extracted using minimally invasive surgery.Group A was left untreated(control group),for group B gelatin sponge was used(gelatin sponge group),for group C gelatin sponge/Fe2O3nano-particles was used(Fe2O3 nano-particles group).After 2 weeks and 4 weeks,the rats were sacrificed,the mandibles were scanned by micro-CT.The date was three dimensional reconstructed by NRecon software,we analyzed the bone micro structure parameters by CTAn software.We acquired three dimensional images by CTVOx software.After 2 weeks and 4 weeks,BV/TV,BS/BV,BMD of Fe2O3 nano-particles group and control group has statistically significance.Fe2O3 nano-particles have good effect in the site preservation.