Three-Dimensional Regional Displacements After Mandibular Advancement Surgery: One Year of Follow-Up

• Published in: Journal of oral and maxillofacial surgery Vol. 69; no. 5; pp. 1447 - 1457
• Main Authors: Motta, Alexandre T., DDS, MS, PhD, Cevidanes, Lucia H.S., DDS, MS, PhD, Carvalho, Felipe A.R., DDS, Almeida, Marco A.O., DDS, MS, PhD, Phillips, Ceib, BS, MPH, PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.05.2011; Elsevier
• Subjects: Adaptation, Physiological - physiology; Adult; Biological and medical sciences; Cephalometry - methods; Chin - anatomy & histology; Chin - surgery; Cone-Beam Computed Tomography - methods; Dental Occlusion, Centric; Dentistry; Female; Follow-Up Studies; Humans; Image Processing, Computer-Assisted - methods; Imaging, Three-Dimensional - methods; Male; Malocclusion, Angle Class II - surgery; Mandible - anatomy & histology; Mandibular Advancement - instrumentation; Mandibular Advancement - methods; Mandibular Condyle - anatomy & histology; Medical sciences; Osteotomy - methods; Otorhinolaryngology. Stomatology; Prospective Studies; Skull Base - anatomy & histology; Splints; Surgery; Mandible; Treatment; Three dimensional displacement; Follow up study; Stomatology; Surgery
• ISSN: 0278-2391; 1531-5053
• DOI: 10.1016/j.joms.2010.07.018

Purpose To evaluate the association of 3-dimensional changes in the position of the condyles, rami, and chin at splint removal and 1 year after mandibular advancement surgery. Patients and Methods This prospective observational study used preoperative and postoperative scans of 27 subjects presenting with a skeletal Class II jaw relationship with a normal or deep overbite. An automatic technique of cranial base superimposition was used to assess the positional and/or remodeling changes in the anatomic regions of interest. The displacements were visually displayed and quantified using 3-dimensional color maps. The positive and negative values of surface distances in the color maps indicated the direction of the displacements. Pearson correlation coefficients and a linear model for correlated data were used to evaluate the association between the regional displacements. Results The postoperative adaptations in the chin position between splint removal and 1 year after surgery were significantly negatively correlated with changes in the borders of the posterior ramus (left, r = −0.73, P ≤ .0001; and right, r = −0.68, P = .00) and the condyles (left, r = −0.53, P = .01; and right, r = −0.46, P = .02), indicating that these structures tended to be displaced in the same direction. Even though the mean condylar displacement with surgery was less than 1 mm, individual displacements greater than 2 mm with surgery were observed for 24% of the condyles. The condylar displacements were maintained at 1 year after surgery for 17% of the condyles. Conclusions The surface distance displacements indicated that the postoperative adaptations at different anatomic regions were significantly related.