One-year assessment of surgical outcomes in Class III patients using cone beam computed tomography

• Published in: International journal of oral and maxillofacial surgery 2013-06, Vol.42 (6), p.780-789
• Main Authors: de Paula, L.K, Ruellas, A.C.O, Paniagua, B, Styner, M, Turvey, T, Zhu, H, Wang, J, Cevidanes, L.H.S
• Format: Article
• Language: English
• Subjects: Adult; Cephalometry; Chin - diagnostic imaging; class III; Cone-Beam Computed Tomography; Dentistry; Female; Humans; Male; Malocclusion, Angle Class III - diagnostic imaging; Malocclusion, Angle Class III - surgery; Mandible - diagnostic imaging; Mandible - surgery; Mandibular Condyle - diagnostic imaging; Maxilla - diagnostic imaging; Maxilla - surgery; orthognathic surgery; Orthognathic Surgical Procedures - methods; Outcome Assessment (Health Care); Periodontal Splints; Prospective Studies; Secondary Prevention; stability; Subtraction Technique; Surgery; Young Adult
• ISSN: 0901-5027; 1399-0020
• DOI: 10.1016/j.ijom.2013.01.002

Abstract The purpose of this study was to apply a novel method to evaluate surgical outcomes at 1 year after orthognathic surgery for Class III patients undergoing two different surgical protocols. Fifty patients divided equally into two groups (maxillary advancement only and combined with mandibular setback) had cone beam computed tomography (CBCT) scans taken pre-surgery, at splint removal, and at 1-year post-surgery. An automatic cranial base superimposition method was used to register, and shape correspondence was applied to assess, the overall changes between pre-surgery and splint removal (surgical changes) and between splint removal and 1-year post-surgery at the end of orthodontic treatment (post-surgical adaptations). Post-surgical maxillary adaptations were exactly the same for both groups, with 52% of the patients having changes >2 mm. Approximately half of the post-surgical changes in the maxilla for both groups were vertical. The two-jaw group showed significantly greater surgical and post-surgical changes in the ramus, chin, and most of the condylar surfaces ( P < 0.05). Post-surgical adaptation on the anterior part of the chin was also more significant in the two-jaw group ( P < 0.05). Regardless of the type of surgery, marked post-surgical adaptations were observed in the regions evaluated, which explain the adequate maxillary–mandibular relationship at 1-year post-surgery on average, with individual variability.