Study On Finite Element Analysis Of Two Fixed Treatment Methods For Periodontal Loosen

Periodontal disease refers to various diseases that occur in tissues surrounding the teeth(gum,periodontal ligament,alveolar bone,etc.),and is one of the most common diseases in humans.At present,loosen teeth caused by periodontal disease is more serious.While the condition and the patient’s age increase,the severity of loosen teeth also increases.From the end of the 20 th century,the use of periodontal splint(PS)to repair tooth loosening in the clinic has been carried out at home and abroad.However,there are few studies on the mechanics before and after PS repaired loosen teeth.Those cases are needed by mechanical analysis in the clinic.In the clinical cases of loosen teeth fixation,there is a lack of research and analysis on finite element model of periodontal tissue with loosen teeth for PS repair.Scholars’ research on the effect of PS repair only exists in clinical application case analysis,and the specific mechanical distribution relationship between tooth tissues is still unknown.In this paper,the finite analysis software ABAQUS was applyed to simulate the mechanical behavior of the periodontal splint repair loosen teeth under physiological load.The main research methods and results are as follows.The paper establishes finite element model of periodontal tissue,including various models under normal conditions,different degrees of loosen,and different PS repair.The importance of the curved structure of periodontal ligament is considered in the model,as well as the influence of other healthy teeth in a group of teeth exist on the cases of loosen teeth restoration.The effects of different degrees of loosen(Ⅰ degree loosen,Ⅱ degree loosen,Ⅲ degree loosen),different repair methods(fiber band repair,super bond repair),different loading angles(0°,15°,30°)on the mechanical behavioral of periodontal loosen fixation and repair were studied by numerical simulation.The finite element simulations show that different degree loosen and loading angles have significant effect on the mechanical behavior of periodontal tissues.When it is I degree loosen,the loosen teeth in the loosen group are similar to the normal group on displacement nephogram.But the maximum value is quite different.After PS repair,the value is reduced and the displacement cloud layer becomes neat and orderly.And the difference is largest on30 degree loading with PS repair.There is stress concentration in the stress cloud of the loose teeth in the loose tooth group.After PS repair,the maximum Mises stress is reduced and the stress concentration is alleviated.In the normal group and the loose group,the nephogram of stress and displacement are very similar on healthy position of the teeth.And the numerical difference is not large.the fiber band repair group and the super bond repair group,the color band of displacement nephogram in each tooth show uniform stratification phenomenon.And the displacement nephogram is more obvious at 30 degree loading.The stress area of nephogram in each periodontal membrane turns to to the labial and medial side.Under theconditions of Ⅱ degree loosen and Ⅲ degree loosen,the displacement nephogram and the stress nephogram also show similar changes with Ⅰ degree loosen.And the values also change.The theoretical analysis results show that the stress state of the loosen teeth of periodontal tissues is different under different degrees loosen and different loading angles.The displacements and stress values of the teeth increase with the increase of the loading angle on different loading angles,and loosen teeth have the largest change in values.The displacement and stress values of the teeth increase with the increase of the degree loosen on different degree loosen.Under the same loading angle and degree loosen,the loosen tooth value is reduced and close to the normal group after using the fiber band and super bond repair respectively.In this paper,we mainly studies the mechanical behavior of tooth loosening in periodontal tissues.The research results can provide a theoretical reference for the treatment and repair of clinical tooth loosening.