Skeletal Stability after Maxillary Posterior/Superior Movement for Skeletalclass III Deformities: Pterygoid Process Fracture vs. Remova
Skeletal Stability after Maxillary Posterior/Superior Movement for Skeletalclass III Deformities: Pterygoid Process Fracture vs. Remova
The aim of this retrospective study was to evaluate the maxillary stability after Le Fort I
osteotomy with posterior-superior movement using pterygoid process fracture or removal and
mandibular setback surgery for skeletal Class III deformities. To that end, the changes in 28
patients’ three-dimensional (3D) measurement-point coordinates, obtained by cone-beam
computed tomography (CBCT) superimposition, were analyzed. Based on 3D coordinates
obtained preoperatively (T0), immediately postoperatively (T1) and 6 months after surgery
(T2), linear mixed-effects models were applied to the evaluation of postoperative stability.
The 3D cephalometric outcomes for 14 subjects who had undergone pterygoid process
fracture were compared with those for 14 subjects who had undergone pterygoid process
removal. Most of the extent of the postoperative relapse (ΔT2-T1) was within 1 mm. The
posterior-superior maxillary movement of the Le Fort I osteotomy was very stable regardless
of the pterygoid process method (fracture or removal). We therefore concluded that for the
best maxillary posterior-superior movement results, surgeons should primarily consider not
the pterygoid process method (fracture or removal) but rather the anatomic structure of the
pterygoid process, the descending palatine neuromuscular bundles (DPNB), and the extent of
movement desired.
osteotomy with posterior-superior movement using pterygoid process fracture or removal and
mandibular setback surgery for skeletal Class III deformities. To that end, the changes in 28
patients’ three-dimensional (3D) measurement-point coordinates, obtained by cone-beam
computed tomography (CBCT) superimposition, were analyzed. Based on 3D coordinates
obtained preoperatively (T0), immediately postoperatively (T1) and 6 months after surgery
(T2), linear mixed-effects models were applied to the evaluation of postoperative stability.
The 3D cephalometric outcomes for 14 subjects who had undergone pterygoid process
fracture were compared with those for 14 subjects who had undergone pterygoid process
removal. Most of the extent of the postoperative relapse (ΔT2-T1) was within 1 mm. The
posterior-superior maxillary movement of the Le Fort I osteotomy was very stable regardless
of the pterygoid process method (fracture or removal). We therefore concluded that for the
best maxillary posterior-superior movement results, surgeons should primarily consider not
the pterygoid process method (fracture or removal) but rather the anatomic structure of the
pterygoid process, the descending palatine neuromuscular bundles (DPNB), and the extent of
movement desired.