Technique to Determine Tooth Position in the Maxillary Arch

The position and orientation of the maxillary first molar has been measured on adult skulls, study models of young orthodontic patients and pre-treatment adult periodontal patients by Volchansky et al. (World J Othodont 2004). Objective: to develop a simple non-invasive chair-side technique to measure angulation, inclination, rotation and position of the first permanent molar in the maxillary arch, and to compare these observations with previous results. Methods: with ethical approval 26 dental and oral hygiene students between the ages of 19 and 31participated in the study. The first stage was an intra-oral examination to ensure that there were no missing teeth, other than third molars, no crowns and no prostheses. Angulation was determined by the direction of the buccal groove of the first molar, vertical (v), mesial (m) or distal (d). A wax bite was taken to record the mid-line, width of the arch and position of the tooth in the arch; a further wax bite with articulating paper in place was used to record cusp contact for determination of tooth rotation and inclination. Results: each of the desired criteria was found to be discernible. Mean rotation angles were 58.7(sd5.1) for wax bite alone and 59.1 (sd5.2) for wax bite + articulating paper. Conclusions: The wax bite method was confirmed as suitable for simple non-invasive chair-side studies of the criteria listed.