The objectives of this study were to measure the Furcation Entrance Dimensions of first and second permanent molars in Malaysian samples and to compare the Furcation Entrance Dimensions with the blade widths of periodontal Gracey’s curette used for root surface instrumentation. A total of 199 extracted permanent teeth were measured, which comprised of 51 mandibular first molars, 51 mandibular second molars, 45 maxillary first molars and 52 maxillary second molars. Furcation Entrance Dimension was measured using calibrated test gauges. Results showed 51.91% of Furcation Entrance Dimension was