A Study On Manufacture And Clinical Practice Of Dental Root-Cap And Ball-Cap Attachments

Purpose: This subject applys precise processing technique to manufacturefinished and semi-finished root-cap and ball-cap semi-precision attachments . We designed this experiment in order to make dentures more beautiful ,enhance stability and retaining force, decrease damage to abutments and change this situation that usage of abroad attachments is limited because their high cost at now, reduce production cost ,and accelerate attachments be used in a larger range in China. Methods: Preexisting metal pieces are fabricated by pure titanium in lathe. Mould are fabricated through precision-processing technique . Preexisting plastic pieces , caps and washers are fabricated by high polymer in mould. Then use them in clinical practice after testing their material and mechanical behavior . Results:1. The test data of mechanical behavior: Average initial retaining force of the major EVA-cap is 19.6N . Average retaining force of them drop to 6.5N after 3100 remove-wear cycles . Average initial retaining force of the minor EVA-cap is 13.5N . Average retaining force of them drop to 5.8N after 3100 remove-wear cycles . The EVA-cap may be used more than 1000 days in clinical practice . Average initial retaining force of the major Nylon-cap is30.8N . Average retaining force of them drop to 6.2N after 6000 remove-wear cycles . Average initial retaining force of the minor Nylon-cap is 25.5N . Average retaining force of them drop to6.1N after 6000 remove-wear cycles . The Nylon-cap may be used more than 2000 days in clinical practice .2. Usage of 37 dentures with attachments have testfy the operation of use themdon't need high technique and can be grasped easily . Conclusion:1 .The attachments are manufactured by biological material . There is matched size between female and male of the attachments .The retaining force of attachments drop slowly and fit to clinical practice .2. The attachments with Nylon-cap are more excellent than those with EVA-cap in nature of anti-fatige and retaining force . Nylon-cap should be selected when the abutments are health . EVA-cap may be used as transitional denture or be used when the abutments are more or weak .3. The denture with attachments damage abutments less and make a better effect compare with traditional denture in clinical practice , promote stability and accuracy and are beautiful and efficient.4. The most important aspect is that the attachments are made in china .Through this study ,the cost of the type of attachments is reduced, and this will accelerate the development of attachments and make for the attachments be used in a more larger domestic range.