Scanning electron microscope analysis of working ends of standard and modified Gracey curettes

CONTEXT: Gracey curettes are the most frequently used manual instruments in periodontal treatments. AIM: This study aimed to evaluate morphology of working ends of standard and modified Gracey curettes no. 1–2. MATERIALS AND METHODS: Using scanning electron microscopy, four batches of unused standard curettes from seven manufacturers and modified curettes from 6 manufacturers were investigated for blade length, blade width, blade thickness, toe morphology, surface roughness, and cutting-edge morphology. RESULTS: Working ends of the standard Gracey curettes were longer than the modified ones, with mean lengths of 5.65 ± 0.68 and 4.42 ± 0.82 mm, respectively. However, both standard and modified Gracey curettes had comparable widths and thicknesses, with the mean width of 0.86 mm and the mean thickness of 0.71 mm. Most samples had acceptably symmetrical toes, except those from three manufacturers which had unacceptable toes with angulations. Moreover, only two manufacturers produced curettes with smooth blades on all their surfaces. In addition, sharp or functional wire edges were seen in cutting edges of curettes from three manufacturers. CONCLUSIONS: Working ends of standard and modified Gracey curettes could have different morphological features if they were from different manufacturers or different batches. It is suggested that dentists or dental hygienists make a purchase decision based on their knowledge on morphology of a good curette in relation to its intended use in dental practice, rather than their familiarity or the curette's price. Furthermore, the curette needs to be examined using a widely available magnifying device when possible.