The accuracy of the alginate impressions is sufficient for clinical use in orthodontics and produced, with correct storage, acceptable results even after 2 days. Hydrogum®5 impressions proved to be slightly more accurate than the reference material but less dimensionally stable than the Tetrachrom® impressions. The 3M Espe Position Tray™ seemed to be more practical due to a better retentive effect compared to the Opti-Tray made by Profimed.

The CBCT devices evaluated in this study are suitable for taking exact 3D measurements of anatomical structures and meet all requirements for 3D cephalometric analysis.

High bond strengths are required in order to avoid bracket failure during treatment while brackets should be removable. In addition, chair time should be kept at a minimum. Therefore, the aim of this study was to investigate any differences in bracket's bond strength to enamel by reducing the polymerization time and the steps of bonding procedure. Five hundred teeth were randomly allocated into 20 groups. The groups were established considering the investigated curing units (quartz-tungsten-halogen (QTH) and light-emitting diode (LED), each with two different polymerization times) and the used bonding agents (Clearfil SE Bond, Transbond Plus, Ideal1, iBond, and Transbond XT Primer following acid etching). The brackets were debonded using a shear-peel load and used to calculate the bond strength. The location of adhesive failure was registered by using the modified adhesive remnant index (ARI). The influence of the parameters curing unit, curing time, and bonding agent as well as their interaction products on bond strength showed that the bonding agent influenced the bond strength most followed by curing time. The parameter curing unit as well as all the generated interaction products of it showed a lower impact. Regarding the ARI, the bonding agent exhibited also the highest influence. Using a LED resulted in comparable bond strengths as the QTH curing device also at shorter exposure times. Additionally, the two-component self-etching primers showed similar bond strengths compared to the acid-etching method. Chair time can be reduced by using two-component self-etching primers and LED without decrease of bond strength.

Katsumata's asymmetry index can yield well-structured and illustrative views of landmark distribution, thus, suitably allowing for qualitative asymmetry evaluation of OAVS cases and identification of the skeletal regions involved.