Computer-aided Indirect Bonding Versus Traditional Direct Bonding of Brackets in Orthodontic Patients

Accurate bracket positioning is one of the keys for effective orthodontic treatment. Traditionally, orthodontic brackets are positioned one-by-one on the teeth of the patient, with the so-called direct bonding method. In the past, the term indirect bonding defined a technique where the brackets were positioned on a plaster model in order to increase placement precision. A transfer tray was then built on the plaster, incorporating all the brackets mounted. Finally, this transfer tray was positioned in the mouth of the patient, so that all the brackets could be bonded to the teeth at once in the pre-determined position. Several studies have investigated this indirect technique based on plaster models. With computer-aided technology, a new form of digital indirect bonding is now possible. The dentist digitally places the brackets on a virtual 3D model of the teeth. A tray with the brackets' positioning information is then generated with CAD-CAM (computer aided design and manufacturing) technology and the brackets are subsequently indirectly transferred to the teeth. This new approach could possibly save chair time and increase precision. Our profession is today moving towards the virtual reality, and application of such a computer-aided technology method into the clinical work-flow seems definitely promising for our future daily practice. Since the evidence about this new computer-assisted indirect bracket bonding method is very limited, the purpose of this study is to evaluate precision, chair time, and bracket survival by comparing this digital indirect bonding method to the traditional direct bonding method Specific objectives * To assess and compare the accuracy of a conventional direct bonding method with an indirect computer-aided bonding method. * To evaluate chair time and bracket survival related to both bonding methods. Hypothesis Null hypothesis: I. There is no difference in accuracy of bracket placement between the direct and indirect bonding method