comparison of the accuracy of bracket placement with height bracket positioning gauge and boone gauge

background and aims: to obtain maximum advantages from orthodontic fixed appliances and to achieve the desired final occlusion, correct bracket positioning is highly necessary. in order to measure and determine bracket’s height, diverse gauges have been used. the objective of the present study is to determine and compare bracket positioning accuracy by using height bracket positioning gauge (hbpg) and boone gauge (bg). materials and methods: from one patient with class ii divisions 1 malocclusion and mild crowding, 19 sets of stone models were prepared, one set employed to determine the ideal position of brackets and others were divided into two groups: nine sets for bracket placement by hbpg and nine sets by bg. nine clinician placed brackets in one set by using hbpg and in the other by bg. after sectioning the teeth from stone model these were placed inside acrylic mold and were prepared the photographs, these images were imported to a computer. in two groups, the position of each bonded bracket was compared in term of 3 aspects; namely vertical, mesiodistal and angular with ideal position of every bracket. next, the rate of bracket positioning errors was measured. results: mann whitney u test demonstrate that the mean difference in vertical error between hbpg group and bg group is significant (p < 0.001), while it is not significant in mesiodistal and angular error. univariate analysis of variance proved that gauge and tooth type, and the position of tooth in the mouth sides play a major role in the rate of vertical error. conclusions: in general vertical accuracy of bracket positioning by the use of hbpg is more than that of bg. however, there is no difference between two gauges with regard to the mesiodistal and angular errors. key words: bracket positioning, bracket placement, height bracket positioning gauge, boone gauge