Study On Processing And Quantifying Characteristic Parameters Of Tooth Mobility

People usually have to extract their teeth because of teeth loosening. The studies on exploring the pathogenic mechanism and searching for more effective methods of diagnosis and treatment have been a highlight of oral medicine. Tooth mobility means that the loosening degree of natural teeth or dental implant, which is important for clinicians to judge the state of an illness, estimate treatment effect and prognosis of the affected teeth.Nowadays clinical method of evaluating tooth mobility is usually based on the experience by shaking tooth clamped between the two arms of an instrument and appraising subjectively the distance of the two ultimate sites, so this method has many uncertain factors. And parameters of tooth mobility show less value. This situation asks for us to looking for more objective and quantified method. Scholars created all kinds of tooth mobility measurement instruments and extracted general parameter. But many factors can affect tooth mobility, and one parameter can't distinguish them. Researching the relation between situation of tooth supporting tissue and tooth mobility parameters , building up multiple-parameters tooth mobility measurement system and distinguishing factors affecting tooth mobility have not been reported.In this article we extract 6 parameters from FX-1 tooth mobility measurement system- measure model which imitates the changing of alveolarbone height and periodontal membrane width. We observe the teeth applying edgewise appliance and verify the repetition of these parameters. The results are as follow:1. By making a tooth model imitated with human maxillary central incisor, silicone rubber periodontal membrane and resin alveolar bone and utilizing FX-1 tooth mobility measurement system the relationship between tooth-mobility parameter and alveolar height is researched It can be observed that time parameters tK t2 in the tooth mobility signal increase together with the lessening of alveolar height and have significantly negative correlation.2. By making a tooth model imitated with human maxillary central incisor, silicone rubber periodontal membrane and resin alveolar bone and utilizing FX-1 tooth mobility measurement system the signal related to different width of periodontal membrane is elicited and processed. It can be observed that R absolute value of wave range and time parameter t2 have significantly negative correlation with width of penodontal membrane.3. Utilizing FX-1 tooth mobility measurement system and strictly controlling experimental situation, we acquired continuously 5 days' data of tooth mobility parameters Qx R^ S^ K, tK t2 of normal youths'*2K *24, *3K *34. It can be observed that the values of parameters S> K> tK t2 have no significant differences among these days.4. Tooth mobility of *2K *24 of patients who get Angle's class II malocclusions and are applied edgewise appliance for 8-11 days is researched. It is found that parameters Q> FK S vary irregularly before loading and after loading, parameter K decreases with non-significant difference. But parameters tK t2 increase and have significant difference. After loading 8-11 days x-ray films only show that the root cervical pan of periodontal membrane widens lightly.From all the results it can be concluded that time parameters il, t2 in tooth mobility signal can reflect the changing of alveolar bone height. Parameters R ^ t2 are the important indices evaluating the changing of width of periodontal membrane. S, K> tl, t2 are steady indices which can reflect the factors affecting tooth mobility. Combining x-ray films with the former results it can be concluded that time parameters tK t2 can judge the changing of tooth mobility when tooth supporting tissue are changing in early stage.