S. P. Crown 치은연하부위(齒齦緣下部位)의 표면조도(表面租度)에 관(關)한 실험적(實驗的) 고찰(考察)

AN EXPERIMENTAL STUDY ON SURFACE ROUGHNESS OF SUBGINGIVAL AREA OF S. P. CROWN MARGINS.

To evaluate the surface roughness of subgingival area of S. P. crown margins subjected to various polishing procedures, the study was performed by use of metallograph and surface roughness tester. The following results were obtained; 1) Abrasive stone wheel produced the roughest surface ($16.0{\mu}m$). 2) Final polish with rouge after polishing with rubber wheel, subsequent to abrasive stone wheel, produced the smoothest surface ($0.3{\mu}m$). 3) Both polish with rubber wheel after polshing with abrasive stone wheel, and polish with pumice (coarse$\rightarrow$medium$\rightarrow$fine) produced same surface roughness ($0.8{\mu}m$).