RELATIONSHIP BETWEEN DESIGNING OF REMOVABLE PARTIAL DENTURE AND MOVEMENT OF ABUTMENT

为了使可摘局部义齿发挥最佳效果，使义齿的运动尽可能小是至关重要的。但是，如果为了减小义齿的运动而加重基牙的负荷，那就本末倒置了。这是因为需要在不损害基牙的范围内限制义齿的运动。本研究的目的是分析使用多个固位体，特别是根内附着体时基牙的受力分布。首先制作下犬根牙模型，包括牙槽骨、牙周膜和牙龈。接下来，我们选择了hi-corex super， bona 604a， battesti和po-anchor 4种不同的根固位器。此外，我们在每个固位器上固定树脂义齿基托，包括人工牙。最后，我们将这些图形设置在X-Y坐标上。编制了力分布分析软件，并绘制了网格切割图。物体常数（阳泊比）和实验条件，由于力集中实验部位与真实x线照片牙槽骨吸收部位吻合，使用与去年相同的数字和条件。所施加的力的大小是2-5n。考虑到模型为下犬齿，方向由唇向舌。实验结果如下：1.实验结果表明：各牙基牙周围的受力大小和分布不同。这可能是因为材料和/或男女锁紧和/或保持施加机制的位置不同。高齿超齿在牙周的受力分布与其他3种附着体明显不同。这是因为hi-corex应用磁力作为保持力。因此，有必要对磁性附着体的磁场进行分析，以便详细地检查力的分布。

FOR REMOVABLE PARTIAL DENTURE WORKING BEST,IT IS ESSENTIAL TO MAKE THE DENTURE MOVEMENT AS SMALL AS POSSIBLE.BUT,IF THE ABUTMENT TOOTH IS LOADED HEAVILY FOR THE PURPOSE OF MAKING THE DENTURE MOVEMENT SMALLER,IT WOULD BE PUT THE CART BEFORE THE HORSE.THIS IS BECAUSE IT IS NEEDED TO RESTRAIN THE DENTURE MOVEMENT WITHIN THE LIMITS OF NOT DAMAGING THE ABUTMENT TOOTH.THE PURPOSE OF THIS STUDY WAS TO ANALYZE THE FORCE DISTRIBUTION OF ABUTMENT TOOTH IN CASE OF USING SEVERAL RETAINERS,ESPECIALLY INTRA RADICULAR ATTACHMENTS.FIRST,WE MADE ROOT TOOTH MODEL OF LOWER CANINE,INCLUDING ALVEOLAR BONE,PERIODONTAL MEMBRANE AND GINGIVA.NEXT,WE CHOSE 4 DIFFERENT KINDS OF ROOT RETAINERS,HI-COREX SUPER,BONA 604A,BATTESTI AND PO-ANCHOR.IN ADDITION,WE FIXED RESIN DENTURE BASE INCLUDING ARTIFICIAL TOOTH ON EACH RETAINER.Finally, WE SET THOSE FIGURES ON THE X-Y COORDINATES.THE COMPUTER SOFT FOR ANALYZING FORCE DISTRIBUTION IS FINAS AND FEMAP FOR CUTTING THE MESH.AS FOR OBJECT CONSTANT (THE YANG AND POISSON RATIO) AND EXPERIMENTAL CONDITION,THE SAME FIGURES AND CONDITION AS THE LAST YEAR WERE USED BASED ON THE FACT THAT THE EXPERIMENTAL SITE OF FORCE CONCENTRATION WERE COINCIDED WITH THE SITE OF ALVEOLAR BONE RESORPTION OF REAL X-RAY PHOTOGRAPH.THE MAGNITUDE OF FORCE APPLIED WAS 2-5N.AND DIRECTION WAS FROM THE LABIAL TO LINGUAL IN CONSIDERATION OF THE MODEL BEING LOWER CANINE.THE RESULTS WERE AS FOLLOWS ;1.THE FORCE MAGNITUDE AND DISTRIBUTION AROUND ABUTMENT TOOTH DIFFERED FROM EACH RETA5NER.THIS MAY BE BECAUSE THE DIFFERENCE OF THE MATERIAL AND/OR THE POSITION OF MALE AND FEMALE LOCKING AND/OR RETENTION EXERTING MECHANISM.2.THE FORCE DISTRIBUTION OF THE HI-COREX SUPER AROUND TOOTH OBVIOUSLY DIFFERED FROM OTHER 3 ATTACHMENTS.THIS IS BECAUSE THE HI-COREX APPLIES MAGNETIC FORCE AS RETENTIVE FORCE.THEREFORE,IT IS NECESSARY TO ANALYZE MAGNETIC FIELD OF MAGNETIC ATTACHMENT FOR THE PURPOSE OF EXAMINING FORCE DISTRIBUTION IN DETAIL.