Influence of Repeated Use and Sterilization on the Performance of Diamond Burs: An SEM Study

Diamond burs are essential in routine dental practice, with their longevity affected by factors including manufacturing quality, usage frequency, irrigation, applied pressure, and post-use cleaning and sterilization protocols. This study aimed to evaluate the wear characteristics and diamond particle retention of burs from three commercial brands-American Burs (American Burs Inc., Miami, Florida, USA), Kerr (Kerr Corporation, Orange, CA, USA), and KG Sorensen (KG Sorensen, Barueri, São Paulo, Brazil)-in comparison with single-use burs from Chongqing Xishan (Chongqing Xishan Science and Technology Co., Ltd., Chongqing, China) using Scanning Electron Microscopy (SEM). New burs (n = 5 per brand) were gold-sputtered and initially analyzed under SEM to assess the shape, size, and distribution of diamond particles. Each bur was then used to prepare cavities in bovine teeth under standardized conditions for pressure and irrigation. After each use, the burs underwent ultrasonic cleaning and autoclave sterilization. This cycle was repeated five times for each bur. Post-cycling SEM analysis revealed that KG Sorensen burs exhibited the least diamond wear, retained sharp cutting edges, and showed minimal particle loss. American Burs demonstrated moderate wear, rounding of edges, and partial diamond particle loss. Kerr burs showed significant wear, characterized by rounded abrasive surfaces and substantial particle detachment. In contrast, the single-use Chongqing Xishan burs lost nearly all diamond particles after one cycle, exposing the metal substrate. In conclusion, all multi-use burs tested—except the single-use variant—maintained their functional integrity through five clinical cycles. KG Sorensen burs exhibited superior wear resistance and durability, whereas the single-use burs failed to retain their abrasive capacity after the initial use.