M. Cutbirth et al., CONDYLAR RESORPTION AFTER BICORTICAL SCREW FIXATION OF MANDIBULAR ADVANCEMENT, Journal of oral and maxillofacial surgery, 56(2), 1998, pp. 178-182
Purpose: This study evaluated long-term condylar resorption after mand
ibular advancements stabilized with bicortical screws. Patients and Me
thods: One hundred mandibular deficiency patients who underwent bilate
ral sagittal split osteotomies (BSSO) fixed with three bicortical scre
ws per side, and who were followed for a minimum of 1 year with comple
te radiographic records, were evaluated. Preoperative panoramic radiog
raphs were traced and superimposed as a best fit over long-term panora
mic radiographs. Cephalometric tracings were available on all patients
preoperatively, immediately after surgery, 6 to 8 weeks after surgery
, and at long term after surgery. These tracings were used to show the
amount of the initial advancement and any changes that occurred betwe
en 6 to 8 weeks and long term in those patients who exhibited 10% or g
reater changes in their condylar height. Preoperative temporomandibula
r joint signs and symptoms were recorded on all patients before surger
y and at 6 months after surgery. Results: There were 10 patients who h
ad 10% or greater vertical change in their condyles; all changes were
unilateral. Large advancement (P>.009) and preoperative temporomandibu
lar joint symptoms (P>.01) statistically correlated with long-term pos
toperative condylar resorption, There was not a direct correlation bet
ween the amount of vertical change in the condyle and the amount of re
lapse. There was an improvement in temporomandibular joint symptoms fo
r the group as a whole and in the group with condylar resorption. Conc
lusions: Patients with large advancements and preoperative temporomand
ibular joint symptoms appear to be at risk for condylar resorption. Th
ese results are similar to those from other studies in which rigid fix
ation or miniplates were used for cases of mandibular advancement.