OUT WRITTEN PERMISSION FROM THE PUBLISHER.                                             COPYRIGHT © 2001 BY QUINTESSENCE PU...
OUT WRITTEN PERMISSION FROM THE PUBLISHER.                                             COPYRIGHT © 2001 BY QUINTESSENCE PU...
OUT WRITTEN PERMISSION FROM THE PUBLISHER.                 COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING O...
OUT WRITTEN PERMISSION FROM THE PUBLISHER.                                             COPYRIGHT © 2001 BY QUINTESSENCE PU...
OUT WRITTEN PERMISSION FROM THE PUBLISHER.                                             COPYRIGHT © 2001 BY QUINTESSENCE PU...
OUT WRITTEN PERMISSION FROM THE PUBLISHER.                                             COPYRIGHT © 2001 BY QUINTESSENCE PU...
Complications following orthognathic surgery that required ...
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  • Complicazioni conseguenti un intervento di ortognatica che richiedono un intervento di urgenza.
    Affidandosi ad un chirurgo maxillo facciale le complicazioni da intervento di chirurgia ortognatica saranno praticamente inesistenti: http://www.giuseppespinelli.it/chirurgia-estetica-maxillo-facciale/chirurgia-ortognatica.html
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Complications following orthognathic surgery that required ...

  1. 1. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH- 138 Ashraf F. Ayoub, PhD, MDS, FDS RCS, BDS Complications following orthognathic Senior Lecturer/Honorary Consultant Oral and Maxillofacial Surgery surgery that required early surgical Glasgow University Dental Hospital and School intervention: Fifteen years’ experience Canniesburn Hospital The West of Scotland Regional Maxillofacial Unit The aim of this study was to assess complications following various or- Glasgow, United Kingdom thognathic surgical procedures that required early surgical interven- tion. This study was carried out on 821 patients who had undergone Zahid Lalani, FDS RCS, BDS Resident surgical treatment for correction of dentofacial deformities between Oral and Maxillofacial Surgery 1985 and 2000. Only patients who required a second procedure to deal University of Texas at Houston with immediate or early postoperative complications (ie, those occur- Kursheed F. Moos, OBE, ring within 4 weeks of surgery) were investigated in this study. Twelve FDS RCS, FRCS, MBBS, BDS patients underwent a second surgical procedure; 9 had undergone Consultant and Honorary Professor conventional osteotomy surgery, and 3 had undergone distraction os- Oral and Maxillofacial Surgery Glasgow University Dental teogenesis.Three Le Fort I cases had to be further impacted and reposi- Hospital and School tioned, and 4 vertical subsigmoid osteotomies had to be reexplored. The details of the complications are presented, and possible methods Canniesburn Hospital The West of Scotland Regional by which these problems could be reduced and/or prevented are dis- Maxillofacial Unit cussed. (Int J Adult Orthod Orthognath Surg 2001;16:138–144) Glasgow, United Kingdom Graham A. Wood, FDS RCS, FRCS, MBChB, BDS Consultant Oral and Maxillofacial Surgeon Canniesburn Hospital The West of Scotland Regional Maxillofacial Unit Glasgow, United Kingdom Orthognathic correction of dentofacial There are relatively few reports con- Reprint requests: and craniofacial deformities has come a cerning intraoperative complications relat- Dr Ashraf F. Ayoub long way since its invention at the end of ing to mandibular osteotomies, 2,6,19,20–22 Oral and Maxillofacial Surgery Glasgow Dental Hospital and the 19th century. Advances in anesthesia, some of which required a second surgical School neurosurgery, maxillofacial surgery, and crit- intervention. We report in this study our 378 Sauchiehall Street ical care have made it possible to correct fa- last 15 years’ experience of immediate and Glasgow G2 3JZ, United Kingdom Fax: +44 0141 211 9601 cial deformities that in the not-too-distant early postoperative complications that re- E-mail: a.ayoub@dental.gla.ac.uk past were considered untreatable. The Le quired a second surgical procedure in pa- Fort I osteotomy and mandibular ramus tients who had undergone orthognathic surgery (including both the sagittal split surgery. ramus osteotomy and the vertical ramus os- The aims of this study were twofold: teotomy, with or without genioplasties) are the most frequently used methods for cor- 1. To assess the complications that re- rection of dentofacial deformities. Although quired early surgical intervention fol- a large number of studies have been carried lowing various orthognathic surgical out to evaluate the relapse rate following procedures. these procedures,1–7 there are few articles in 2. To investigate the causes of these com- the literature that focus on postoperative plications and the possibility of their complications. The most frequently men- prevention. tioned are lesions of the inferior dental nerve,8–11 fractures of the mandibular proxi- Materials and methods mal segment, 12,13 incomplete section- Int J Adult Orthod Orthognath Surg ing,9,13,14 malpositioning of segments,14,15 This study was carried out on all patients Vol. 16, No. 2, 2001 and severe hemorrhage.5,11,13,16–18 who had undergone surgical treatment for
  2. 2. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH- Int J Adult Orthod Orthognath Surg Vol. 16, No. 2, 2001 139 correction of dentofacial deformities be- Here, the cuts were made inadequately and tween January 1985 and January 2000 at did not reach the posterior border of the Canniesburn Hospital at the West of Scot- mandible, so that distraction proceeded in land Regional Maxillofacial Unit. Only pa- the anterior part of the ramus but not pos- tients who required a second procedure to teriorly. This was recognized and required deal with immediate or early postoperative further surgery to effect the appropriate complications (ie, those occurring within 4 movement (Figs 2a and 2b).There were also weeks of surgery) were investigated in this 2 Le Fort I cases. Both patients had severe study. The case notes and radiographs of bilateral cleft deformities in which there these patients were reviewed, and the fol- was a large discrepancy in an anteroposte- lowing parameters were investigated: pre- rior direction that could not be treated eas- operative diagnosis, operative procedure, ily by conventional osteotomy surgery, es- postoperative complications, the interval pecially as they had undergone extensive between the 2 surgical procedures, and the previous surgery. In both cases these failed type of secondary surgery performed. because of problems with cranial fixation using a modified halo frame and pins; in Results one case there was a complete lack of pa- tient cooperation and in the other the A total of 821 patients who had under- frame became loose and had to be read- gone orthognathic surgery during the last justed under general anesthesia. 15 years were identified. The age of pa- tients ranged from 13 to 44 years, with a Discussion mean of 27 years. Twelve patients returned to the operating room within 1 month of Although in the past (during the late the initial surgical procedure for the cor- 1970s and early 1980s), 2 patients had re- rection of their deformity (Table 1). The pa- ceived a second emergency surgery be- tients can be grouped into those who had cause of excessive bleeding (1 from a ge- conventional osteotomy surgery (n = 9) nioplasty and the other from a Le Fort III and those who received distraction osteo- osteotomy), in this cohort, no patients re- genesis (n = 3). Among the osteotomy pa- quired emergency surgery. All patients tients, there were 7 bimaxillary cases, 3 of who required further surgery were treated which were Le Fort I osteotomies that had within a period of 2 to 21 days. The major- to be further impacted and repositioned ity of cases had bimaxillary surgery, the and 4 of which were vertical subsigmoid most commonly performed operation. The osteotomies that had to be reexplored. In 3 most frequent of the combined procedures of the vertical subsigmoid patients, the that were carried out were the Le Fort I os- proximal fragments were incorrectly teotomy and the vertical subsigmoid set- placed and had to be repositioned (Figs 1a back osteotomy. The bilateral sagittal split and 1b), and in 1 patient the proximal frag- osteotomy tended to be reserved mostly ments on both sides were laterally dis- for patients with mandibular retrusion, placed and very prominent and needed to with only a few cases of mandibular set- be trimmed. One bilateral sagittal split os- back for mandibular prognathism. The teotomy was incorrectly positioned, which mandibular body ostectomy is not a com- required removal of screws and reposition- monly undertaken procedure, but in our ing of the segments. In addition, a single- experience over many years, only 1 patient jaw surgery patient who had bilateral body required repositioning because of inaccu- ostectomies had the distal fragment incor- rate placement of the anterior segment rectly positioned in the splint anteriorly; (distal) in a cast silver cap splint. this needed to be repositioned. Distraction osteogenesis has been car- With respect to the 3 distraction pa- ried out in our facility only since late 1994. tients, all were early cases in our experience. There was a definite learning curve en- One was our first case of distraction of the countered with the procedure, but with mandibular ramus using an external appa- mandibular surgery only 1 patient re- ratus on a hemifacial microsomia patient. quired a second surgery. In the patient
  3. 3. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH-Table 1 Summary of complications and their treatment 140 Date Date of first Date of second of birth surgery surgery Second DaysPatient Sex (m/d/y) Diagnosis Surgical procedure (m/d/y) Complication (m/d/y) surgical procedure inter ops Follow-upCB F 11/25/61 Vertical maxillary excess, narrow Bimaxillary: Le Fort I advancement 6/12/92 Anterior open bite from 6/18/92 Revised Le Fort I poste- 6 At 1 year, slight Ayoub et al maxilla, mandibular protrusion, and anterior setdown with poste- condylar distraction rior impaction and mandibular relapse, and progenia rior rise; bilateral sagittal split ad- (posterior maxillary redid genioplasty but acceptable vancement; genioplasty setback excess)PC F 9/25/52 Maxillary hypoplasia, (retrusion) Le Fort I—2 piece advancement; 3/11/94 Malposition of left VSS 3/29/94 Repositioned left 8 Stable result as of asymmetry, prognathism, asymmetric VSS osteotomy; ante- (occlusal discrepancy) condylar segment 11/30/94 (still OK) macrogenia rior mandible segment setdown (proximal segment of VSS) and trimmedGE M 7/1/75 Bilateral 2-degree cleft deformity, 1) Distraction osteogenesis Le Fort I 10/12/98 Mechanical problems, 11/2/98 2) Wired splints in max- 21 Complete failure, no gross maxillary hypoplasia—no advancement/setdown splint off illa and remanipulated cooperation, no pre-maxilla (failed osteotomy) the whole segment long-term advance- (drug addict/prisoner) ment achieved 3) Redid osteotomy; rewired 11/27/98 Mobile Le Fort I after 1/22/99 (57) (failed to progress) trauma to midfaceTG F 4/30/69 Maxillary hypoplasia, mandibular Bimaxillary surgery: high Le Fort I 11/9/90 Left proximal segment 11/13/90 Reduced left proximal 2 Stable at 5 years prognathism, macrogenia advancement; bilateral VSS set- kicked back, lying lat- segment/sigmoid (increased lower face height) back; genioplasty—vertical reduc- eral; occlusal discrep- notch and coro- tion and advancement ancy; lateral open bite noidectomyGL F 7/21/81 Hemifacial microsomia, mandibu- Distraction osteogenesis (corti- 12/20/94 Failed to complete cuts 1/9/96 Redid posterior cuts 20 Excellent result, stable lar asymmetry, small right side cotomy) of right mandible— in ramus ramusSMc M 3/11/74 Bilateral 2-degree cleft deformity, Le Fort I distraction osteogenesis; 5/27/99 Failed pins and loose 6/7/99 Repositioned and fixed; 10 Late adequate result collapse of lesser segments in splints to halo fixation; vertical halo later, redid Le Fort I previous premaxillary os- and horizontal advancement and bone graft teotomy, vertical maxillary (2/18/00) deficiencyJMc F 1/30/68 Asymmetric maxillary hypoplasia, Le Fort I advancement and im- 8/11/95 Occlusal discrepancy of 8/30/95 Repositioned maxilla at 19 Stable, good late re- asymmetric mandibular prog- paction shift to right; asymmetric maxilla to the right, correct cant and repo- sult, very slight ante- nathism, retrogenia, anterior mandibular VSS setback; advance- anterior open bite sitioned VSS rior open bite open bite ment/vertical reduction genio- plastyAM F 8/17/66 Maxillary retrusion and vertical Le Fort I—3 part advancement and 7/15/88 Incorrect mandibular 7/29/88 Redid mandibular set- 14 Stable after third deficiency (flared alar bases), inferior reposition of the setback; malocclusion back, screws reposi- operation mandibular prognathism and mandible (setback); bilateral and anterior open bite tioned and maxillo- progenia, slight asymmetry sagittal split genioplasty setback (excessive on the left) mandibular fixation; late relapse in 1993— redid 2-part Le Fort ILQ F 3/10/56 Vertical maxillary excess, deep Le Fort I and impaction anterior > 5/23/90 Le Fort I: insufficient 5/30/90 Redid Le Fort I, posterior 7 Good long-term stable anterior occlusion, mandibular posterior, augmentation genio- bone removed poste- rise-plated result retrusion, retrogenia plasty, titanium mesh fixation riorly (condyles out of fossae)FS-Q F 1/12/64 Maxillary retrusion and posterior Le Fort I advancement, posterior 12/18/98 Very prominent angles 1/6/99 Smoothed proximal 19 Slight anterior open vertical maxillary excess, impaction: anterior downgraft, of proximal fragments fragments to fit, repo- bite relapse mandibular prognathism, VSS setback, vertical reduction sitioning plus maxillo- asymmetry and macrogenia, and setback, genioplasty mandibular fixation anterior open biteLS F 7/26/71 Maxillary retrusion and vertical Le Fort I rise/advancement VSS set- 1/21/90 Left proximal fragment 1/26/90 Left proximal fragment 5 Stable, OK at 5 years maxillary excess, mandibular back, genioplasty, vertical reduc- posteriorly displaced, of VSS trimmed and prognathism, anterior open bite tion setback occlusal discrepancy repositionedPW F 6/20/65 Mandibular prognathism, Asymmetric mandibular setback, Inadequate correction 9/5/90 Bilateral body ostec- (21⁄2 years) Stable after 1997 3/9/88 asymmetric progenia and genioplasty to right tomy and genioplasty macrogenia left side, crossbite Readjust anterior segment, proplast Segment not in splint to right with bone 9/7/90 2 genioplasty graftingVSS = vertical subsigmoid segment
  4. 4. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH- Int J Adult Orthod Orthognath Surg Vol. 16, No. 2, 2001 141 Fig 1a Immediate postoperative radiograph showing lateral and infe- Fig 1b Radiographic appearance of the same patient following trim- rior displacement of the condylar segment following vertical subsig- ming of the inferior tip and suturing of the condylar segment to the moid osteotomy. ramus of the mandible. Fig 2a Incomplete osteotomy of the posterior border of the mandible Fig 2b Radiograph of the same patient showing successful lengthen- following distraction osteogenesis, which required a second surgical in- ing of the ramus following this intervention. tervention.
  5. 5. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH- 142 Ayoub et al who underwent midface surgery, there proach also carried the risk of anesthesia or were clearly problems with our distraction paresthesias as a result of trauma to the in- device, which was locally developed. How- ferior alveolar nerve. In 1968 Winstanley25 ever, more recently, apparatus problems described an intraoral subcondylar ap- have proven to be much less troublesome. proach to the lateral aspect of the ramus, Twelve patients, who constituted approx- with use of a long-shank rotary bur. He re- imately 1.5% of the total number of patients ported that this approach was more diffi- treated, had to undergo a second surgical cult to perform than an extraoral approach. procedure as a result of early postoperative To improve visibility, access, and instru- complications. All of these patients had their mentation of the intraoral ramus os- second surgery within 4 weeks of the date teotomy, several authors recommended of their initial surgery. Seventy-five percent the use of the Stryker oscillating saw with of the patients presented with a malocclu- an angled blade, in addition to a specially sion as a result of either improper position- designed posterior border retractor (Le ing of the maxilla or the mandible, and the Vasseur-Merrill).27 A fiberoptic light, either other 25% included the distraction cases on the mandibular retractor or on a suc- and 1 vertical subsigmoid osteotomy that tion tip, was also advocated.27 simply required the trimming of both proxi- To promote early union between the mal fragments because of their prominence. condylar segment and the rest of the ramus, With respect to the vertical subsigmoid os- Caldwell and Letterman26 recommended teotomies, 3 of the 4 patients showed im- decortication of the lateral surface of the proper positioning of the proximal segment ramus, fixation with direct wiring, and on one side, usually into a posterior position. drilling holes. Hall et al27 found that in cases One of the osteotomy patients had had pre- where the condylar segment was left free, vious early surgery, and 1 bimaxillary patient some degree of condylar “sag” (anterior-in- required further surgery some 5 years later. ferior displacement) occurred. Some of One maxillary distraction patient (drug ad- these required condylar segment reposi- dict) was lost to follow-up and did not wish tioning and wiring. They also observed that to proceed with further surgery, and the open bite secondary to intraoral vertical other early failed maxillary distraction pa- subsigmoid osteotomy occurred about tient had a further Le Fort I osteotomy and twice as often in patients without wire fixa- bone grafting about 8 months later. Failure tion of the condylar segments, versus pa- to adequately raise the maxilla in anterior tients who received fixation. In their study, open bite patients, or where there was verti- no open bites occurred following the adop- cal maxillary excess, was sometimes a prob- tion of the circumramus wiring technique lem, as were posterior displacements of the after the ramus osteotomy. proximal fragment in the vertical subsig- To minimize postoperative condylar sag, moid osteotomy. Hall et al27 recommended limited stripping Correction of mandibular prognathism of the medial pterygoid muscle attach- by extraoral oblique osteotomy was first re- ment, explaining that an osteotomy that ported by Robinson23 in 1956 and Hinds24 was too near the posterior border of the in 1957. The technique has been character- vertical ramus would leave a small mass of ized as a simple approach that provides ad- muscle attached to the proximal segment, equate visibility of the operative field. How- which might result in more sag. On the ever, damage to the facial nerve and scar other hand, in a national survey of intraoral formation were the basic complications of vertical subsigmoid osteotomies, 73% of the extraoral approach to the ramus. In respondents left the proximal segment un- 1963 Moose1 described a subcondylar os- fixed. Of those who used fixation, more pre- teotomy from the medial side of the ferred transosseous to circumramus wire.23 mandibular ramus. The procedure had sev- In our patients, the proximal segments eral disadvantages. Patients with a diver- were not wired to the distal segments fol- gent mandibular ramus were difficult to lowing the vertical subsigmoid segment operate on because of poor visibility and osteotomy. Only 4 patients showed radio- poor access to the sigmoid notch. This ap- graphic evidence of lateral displacement
  6. 6. OUT WRITTEN PERMISSION FROM THE PUBLISHER. COPYRIGHT © 2001 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITH- Int J Adult Orthod Orthognath Surg Vol. 16, No. 2, 2001 143 and significant condylar sag. Suturing of There is a learning curve associated with the condylar segment with a resorbable the procedures, and with the development material to the periosteal covering overly- of working protocols, the complications as- ing the distal segment was sufficient to sociated with this surgery will be reduced. control condylar positioning. We would Much work is also proceeding with the de- recommend temporary immobilization of velopment of new distraction devices, and the proximal segment to the ramus of the these will no doubt become more reliable mandible. Condylar sagging and lateral or over a period of time. medial displacement of the condylar seg- This audit of complications necessitat- ment were unpredictable. The position of ing a second surgical intervention has the proximal segment intraoperatively may proved instructive to us and should reduce be altered immediately following surgery, problems for patients related to lack of sur- mainly as a result of changes in the pa- gical experience and the expense to our tient’s posture, changes in muscle tone, and Health Service. reattachment of soft tissues to the proxi- mal segment. The amount of condylar sag References is a function of the laxity of the soft tissue attached to the proximal segment, includ- 1. Moose SM. Surgical correction of mandibular prognathism by intraoral subcondylar oste- ing the medial pterygoid muscle. There- otomy. Br J Oral Surg 1963;1:172–176. fore, we would recommend minimal strip- 2. Moser L, Freihofer HP. Long-term experience with ping of the medial pterygoid muscle simultaneous movement of the upper and lower jaw. J Maxillofac Surg 1980;8:271–277. attachment, just enough to allow the 3. Proffit WR, Philips C, Dann C, Turvey TA. Stability mandibular setback. Wiring of the proximal after surgical-orthodontic correction of skeletal segment to the ramus of the mandible is a Class III malocclusion. I. Mandibular setback. Int J Adult Orthod Orthognath Surg 1991;6:7–18. controversial issue, and until a prospective 4. Proffit WR, Philips C, Prewitt JW, Turvey TA. Stabil- randomized trial is undertaken to assess its ity after surgical-orthodontic correction of skele- effect on mandibular stability, it would be tal Class III malocclusion. II. Maxillary advance- ment. Int J Adult Orthod Orthognath Surg 1991; difficult on a scientific basis to recommend 6:71–80. one technique over another. 5. Proffit WR, Philips C, Turvey TA. Stability after sur- With regard to some of the other com- gical-orthodontic correction of skeletal Class III malocclusion. III. Combined maxillar y and plications that occurred in our case series, mandibular procedures. Int J Adult Orthod Or- there is no doubt that it is difficult to raise thognath Surg 1991;6:211–225. the maxilla in the Le Fort I osteotomy for 6. Stella JP, Astrand P. Patterns and etiology of re- lapse after correction of Class III open bite via the correction of posterior maxillary ex- subcondylar ramus osteotomy. Int J Adult Or- cess. There is a tendency to “under-do” this thod Orthognath Surg 1986;1:91–99. and in the process distract the mandibular 7. Hiranaka DK, Kelly JP. Stability of simultaneous or thognathic surger y on the maxilla and condyles out of their fossae. Cases in which mandible: A computer-assisted cephalometric this occurred partially reflected the inexpe- study. Int J Adult Orthod Orthognath Surg 1987; rience of those carrying out the surgery. 2:193–214. 8. Behrmann SJ. Complications of sagittal os- Very careful assessment of this operation is teotomy of mandibular ramus. J Oral Surg 1972; essential and can be helped by the use of 30:554–561. thin occlusal acrylic wafers that have been 9. Brusati R, Fiamminghi L, Sesenna E, Gazzotti A. Functional disturbances of the inferior alveolar accurately constructed preoperatively nerve after sagittal osteotomy of the mandibular using anatomic articulation. It is also im- ramus: Operating technique for prevention. J portant during the testing of the occlusion Maxillofac Surg 1981;9:123–125. 10. Mercier P. The inner osseous architecture and the that there is no tendency to tip the chin sagittal splitting of the ascending ramus of the forward and distract the condyles; upward mandible. J Maxillofac Surg 1973;1:171–176. pressure in the angle regions of the 11. White RP, Peters PB, Costich ER, Page HL. Evalua- tion of sagittal split ramus osteotomy in 17 pa- mandible to maintain the condyles in the tients. J Oral Surg 1969;27:851–855. fossae when undertaking this rotation 12. Epker BN, Wessberg GA. Mechanisms of early should prevent this complication. skeletal relapse following surgical advancement of the mandible. Br J Oral Surg 1982;20:175–182. As far as distraction osteogenesis is con- 13. Guernsey LH, De Champlain RW. Sequelae and cerned, we have reported elsewhere the complications of the intraoral sagittal osteotomy problems associated with this technique.29 in the mandibular rami. Oral Surg 1971;32: 176–192.

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