Bizopen Diamond Bur Tapered Fissure 847-012 Fine Grit

The Bizopen Diamond Bur Tapered Fissure 847-012 Fine Grit is the finishing instrument in the three-step axial wall preparation sequence for crown preparations where the final preparation surface and finish line must meet the quality standard required for accurate impression reproduction and ceramic restoration seating. Following bulk axial reduction with the coarse 847-018 and intermediate refinement with the standard 847-016, the fine grit 847-012 produces the smooth 2 to 4 micron Ra preparation surface that both conventional impression materials and intraoral scanner optical systems require for reliable preparation surface capture. The 1.2 mm maximum diameter tapered body is slightly narrower than the coarse and standard grit equivalents, allowing the fine grit instrument to clean into the preparation corner at the axio-gingival junction and produce a clean, smooth finish line edge without the preparation wall roughness that would interrupt the impression material flow at the margin. Fine grit tapered fissure burs are particularly effective on preparations for ceramic materials with tight marginal fit requirements — lithium disilicate, zirconia, and feldspathic porcelain restorations all benefit from the smooth marginal preparation surface that the fine grit produces. The 6-degree taper maintains the same draft geometry as the coarse and standard grit instruments in the sequence. FG shank. ISO 806 314 110 514 012. Maximum working diameter: 1.2 mm. Working length: 6.0 mm.