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Repair dentition defect not only to repair missing teeth, to restore chewing function, but also to maintain the integrity of the dentition, the protection of the remaining teeth, health reserved loose teeth. Loose teeth due to the absorption of alveolar bone, teeth bite and adjacent relations changes also reduce the tolerance threshold force, force (occlusal) are easy to make on the teeth periodontal overburdened accelerated periodontal tissue destruction. However, some of the lesser severity or long-term retention, proper handling of loose teeth can even selected as the dentures abutments, avoid excessive extraction, preservation of alveolar bone, reducing the number of the mill cut natural teeth, denture design simple and take wearing a convenient, comfortable and has a very important significance. The loose teeth diagnosis, treatment and loose denture abutments Design is the the clinical repair work in one of the more difficult issues. Therefore, the correct assessment of the physiological function of the loose teeth, rational design of dentures, to reduce loose teeth by chewing process is the key to maintaining teeth healthy and to extend the life of loose abutment and denture long-term function effectively. But not yet measuring test instruments reported chewing movement of a single tooth (occlusal) surface chewing force change, the relationship on loose teeth (occlusion) force and its influencing factors, and loose teeth chewing force changes in the characteristics of the study reported less. To this end, the study by clinical investigation, analysis loose teeth (occlusal) the variation of the force as well as the impact of loose teeth force of factors, including the degree of alveolar bone resorption, crown-root ratio, adjacency, (occlusal ) relationship, tooth wear degree; PVDF piezoelectric film as a sensing element, for the first time developed a measurement system suitable for measuring the force of a single natural tooth chewing, and irritation to the PVDF piezoelectric film, Cytotoxicity, sensitizing , hemolytic properties for a preliminary evaluation; masticatory force measurement system developed to analyze normal teeth and loose teeth clenched, to knock teeth side (occlusal) movement Tsui Fourth Military Medical University Doctoral Dissertation chewing force changes in the law. The results show that: 1. Loose teeth evil power value significantly different due to inter-individual teeth bit different; obvious negative correlation between the biggest evil power value of the degree of alveolar bone resorption; the maximum evil energy value with crown-root ratio exponential function related crown-root ratio increase the maximum evil energy value lower. 2. Has a close relationship to the evil face wear degree of tooth mobility, loose teeth l attrition, no attrition: no significant loosening and wear depends on the value of IH degrees loose a significant difference between 11, Ill. no significant difference between the degree of loose; loose before the location of the point of tooth wear consistent with normal teeth, the location of the point of the posterior teeth wear irregular distribution. 3. Teeth easily cause the front teeth to cover evil probe, ultra-evil type of evil; When two adjacent teeth are 1 degree loose a tooth loose more than 11 degrees, the loss of adjacency relationship. 4. PVDF piezoelectric film has good biocompatibility; area size, the degree of bending is less impact on the measurement results; PVDF chewing force tester sensor test head thin, stable performance, high sensitivity and dynamic, high signal-to-noise ratio, repeat Good, directly applicable to clinical determination. 5. Knocking teeth movement teeth chewing force peak average 24 ~ 27kg, reaches a peak time for the 100 to 11 oms 27 ~~ 30kg; the biting movement chewing force peak, time to peak around 800ms; side traders move The maximum peak chewing force for 26 ~ 28kg, and the chewing force changes can be divided into five stages. Subjects with unilateral chewing habit, knocking teeth, clenching and side tire movement, the main function of the side chewing force peak is greater than the side of the main function, shorter time to peak. 6. Knocking teeth, clenching the side of evil movement in loose teeth chewing force peak is less than the contralateral, long time to peak. Therefore, chewing movements, loose teeth chewing force involved in the North rose speed is lower than that of normal teeth. Suggesting the need to tune evil loose teeth by chewing movement to reduce lateral force down meal in order to improve the teeth crown root ratio, reducing oral preparation in clinical prosthodontics. II - the Fourth Military Medical University Doctoral Dissertation roots weeks stress; denture design, in loose tooth set on the bracket the interproximal hook, high card, if necessary, also can be used splints to play a fixed loose teeth, reduce the role of loose teeth displacement, restorations to get a good long-term efficacy.
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