Application of surgical guide for pre-drilling for the successful placement of orthodontic mini-screws using CAD/CAM technology in two cases

Abstract

An increasing number of clinicians have been utilising orthodontic mini-screws as temporary anchorage devices (TAD) in their practices, but variable successful rates have been reported. Here, we introduce a practical approach to inserting mini-screws successfully. Using computer-aided design (CAD) and computer-aided manufacturing (CAM) technology, the surgical guide for pre-drilling was designed and fabricated and mini-screws were placed following pre-drilling holes in two cases. Two Ø2.0 × 10.0-mm mini-screws were inserted into the prepared holes in the mandibular buccal shelf (MBS) on both sides with a hand driver to distalise the lower molars for Class III correction. The treatment was done successfully, after 12 months of treatment in one case. Two Ø1.6 × 8.0-mm mini-screws were inserted into the prepared holes in the mandibular alveolar process in another case with congenital absence of lower right second premolar. One mini-screw was in the buccal alveolar process between the mandibular right canine and first premolar and the other in the lingual alveolar process between the mandibular right first premolar and second primary molar. The lower right molars would be protracted to close the space left after the extraction of the primary molar using the two mini-screws. The case was still in treatment.