![Figure 1](/ServeContent?url=http%3A%2F%2Fdbm.sagepub.com%2Fcontent%2F1%2F1%2F502318%2FF1.medium.gif)
Picture of the device used to extract a whole tooth, which is similar to that reported by Yoshimatsu et al. (1956) [5] and modified after Chiba and Ohkawa [6]. The crown of the tooth is held by the clamp, which is connected to a load cell of a materials testing machine. The holding device is fixed to a crosshead of the machine, which moves downwards to measure extraction force.