전기성형술로 제작된 외관의 유지력에 내관의 축면경사도와 표면적이 미치는 영향
EFFECT OF TAPER AND SURFACE AREA OF INNER CROWN ON THE RETENTIVE FORCE OF ELECTROFORMED OUTER CROWN
강완근, 전윤경, 전유진, 임장섭, 정희찬,
소속 상세정보
강완근 ( Kang Wan-Keun ) - 부산대학교 치과대학 치과보철학교실
전윤경 ( Jeon Yun-Kyung ) - 부산대학교 치과대학 치과보철학교실
전유진 ( Jeon You-Jin ) - 부산대학교 치과대학 치과보철학교실
임장섭 ( Lim Jang-Seop ) - 부산대학교 치과대학 치과보철학교실
정희찬 ( Jeong Hee-Chan ) - 부산대학교 치과대학 치과보철학교실
KMID : 0362420060440020165
Abstract
Purpose: With gold electroforming system fir the double crown, the secondary crown is electroformed directly onto the primary crown. An even thick layer of high precision can be acquired. It is thought that the retention of electroformed outer crown is primarily acquired by the adhesive force (surface tension) through the saliva which is interposed between precisely fitted inner and outer crown. The purpose of this study was to investigate the effect of taper and surface area of inner crown on the retentive force of electroformed outer crown according to the presence of saliva.
Materials and methods: 32 titanium inner crowns with cervical diameter of 8 mm and cone angles of 0, 2, 4, 6 degrees, which had same surface area by regulated height, were machined on a lathe. Another 32 titanium inner crowns with cone angles of 0, 2, 4, 6 degrees, which had doubled surface area by increased cervical diameter. were fabricated. Eight specimens of each group, for a total of 64 titanium inner crowns, were prepared. The electroformed outer crowns were fabricated directly on the inner crowns by using electroforming machine(GAMMAT free, Gramm Technik, Germany). The tertiary frameworks were waxed-up on the electroformed outer crown and cast using nonprecious alloy(Rexillium(R)III,Jeneric(R)/Pentronh(R) Inc., USA). The cast metal frameworks were sandblasted with alubimium oxides and cemented using resin cement(Superbond C&B, Sun Medical Co., Japan) over the electroformed copings of each specimen. Then, artificial saliva(Taliva(R), Halim Pharm. Co., Korea) was sprayed between the inner and outer crown, and they were connected under 5 kg force. The retentive force was measured by the universal testing machine(Tinius Olsen 1000, Tinius Olsen, USA) with a cross-head speed of 66.67 mm/sec. The direction of cross-head travel was exactly aligned with the path of removal of the respective specimens. This measurement procedures for retentive force of electroformed outer crown with artificial saliva were repeated in the same way without presence of artificial saliva.
Results and Conclusion: The following conclusions were drawn: 1. The retentive force of electroformed outer crown was decreased according to increased taper of inner crown(P<.05). 2. The retentive force of electroformed outer crown showed no significant differences according to surface area and the presence of artificial saliva(P>.05).
키워드
Electroforming technique;Retentive force;Surface area;Taper
원문 및 링크아웃 정보
등재저널 정보