Molar Mesialisation

This adult male required orthodontic decompensation and then a mandibular setback osteotomy to correct his Class III malocclusion. The lower right 1st molar had a poor prognosis yet space closure would normally be contra-indicated by the need to advance the lower incisors pre-operatively. Conventionally the lower 3rd molar would also be removed during this jaw surgery. Therefore, it was planned to close the 1st molar space by pre-operative mesialisation of the adjacent molars and hence preserve the 3rd molar in this quadrant.

Normally one mini-implant (placed in the premolar area) would suffice for mesio-distal anchorage, but a 2nd was added here because space closure was greatly complicated by a substantial loss of alveolar height in the 1st molar area. The Infinitas mini-implants were 1.5mm diameter, and had 6mm and 9mm body lengths, inserted buccal and mesial to each premolar root.

Direct traction was applied, via elastic modules, to both a free-sliding powerarm (distal to the 2nd molar) and to the 3rd molar bracket hook. These powerarms enable better bodily movement of teeth with fewer side-effects such as archwire binding.