Preliminary study to establish a relationship between tactile sensation and surface roughness

This study evaluated the ability of tactile sensations to distinguish roughness. Five examiners experienced in visual examination participated. Tactile sensation was assessed by 3 standard references, the average roughnesses 0.49, 0.92 and 1.54 mum. The examiners evaluated the roughness using 2 different ends of sharp explorers (TU 17 SE and 23 SE), each with 2 different handles (Standard Handle and No. 6 Handle-Satin Steel), and 1 WHO probe using a 5-point response score. The examiners performed 3 evaluations to establish repeatability. Using the 23 SE explorer with the steel handle was the best option to distinguish between 3 roughnesses (p < 0.05). The intraexaminer intraclass correlation coefficients (ICC) were between 0.90 and 0.98, but the interexaminer ICC were only between 0 and 0.04, indicating that, although trained examiners could repeat their own scores, they were not consistent with each other in grading roughness.