Two Hundred Ninety-Four Consecutive Facial Fractures in an Urban Trauma Center: Lessons Learned

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1 CME Two Hundred Ninety-Four Consecutive Facial Fractures in an Urban Trauma Center: Lessons Learned Patrick Kelley, M.D., Marcus Crawford, M.D., Stephen Higuera, M.D., and Larry H. Hollier, M.D. Houston, Texas Learning Objectives: After studying this article, the participant should be able to: 1. Understand the different technical options available for repairing facial fractures. 2. Know which technical points facilitate performance of fixation of the facial skeleton by relatively inexperienced surgeons. 3. Have a basic understanding of the most common complications arising after facial fracture repair. 4. Have an understanding of how to avoid surgical complications following facial fracture repair. Background: The treatment of facial trauma is associated with a myriad of potential complications. This may be compounded by the relative lack of compliance seen in the patient population within an urban trauma center and by the requisite involvement of residents in this care. Methods: This study retrospectively evaluated 189 patients with a total of 294 separate fractures treated over a 3.5-year period. Results: The overall rate of complications was 7.8 percent. Conclusions: The experience at a high-volume level I trauma center with residents as the primary physicians has confirmed that facial trauma surgery may be undertaken with an acceptably low complication rate. Numerous technical factors were thought to be responsible for this, including the use of miniplates for treatment in the majority of mandibular fractures, overcorrection of orbital volume in fractures involving the globe, and the use of a transconjunctival incision with a lateral canthotomy for access to the lower eyelid structures. (Plast. Reconstr. Surg. 116: 42e, 2005.) Among the myriad injuries seen in urban trauma centers, facial trauma is one of the most common. Given the broad variety of facial bone injuries seen, management can be complicated even for the most experienced clinician. This takes on added significance when one considers that residents in training are frequently involved in the care of these patients. Although there are numerous ways to handle many facial skeletal injuries, the experienced surgeon entrusted with the training of residents must always be cognizant of emphasizing those methods that provide the desired outcome for the relative novice. Only as trainees become more skilled with their technique should more complex methods be introduced. This study evaluated a large group of patients at a level I urban trauma center undergoing surgical management of facial skeletal injuries. In all cases, the same faculty plastic surgeon (and senior author, Dr. Hollier) was scrubbed with a sixth-year plastic surgery resident acting in the capacity of surgeon. The results of these operations in terms of complications were examined. Technical aspects of the operation, which were thought to improve the overall outcome while minimizing the complexity of the procedure itself, are examined. From the Michael E. DeBakey Department of Surgery, Division of Plastic and Reconstructive Surgery, Baylor College of Medicine. Received for publication August 6, 2004; revised December 14, DOI: /01.prs e

2 Vol. 116, No. 3 / FACIAL FRACTURES IN A TRAUMA CENTER PATIENTS AND METHODS We performed a retrospective analysis of 189 patients with facial fractures treated at Ben Taub General Hospital in Houston, Texas, from September of 1998 to February of All of the patients were treated by residents on the plastic surgery service under the supervision of one faculty surgeon at this level I trauma center. Data were analyzed according to demographics, mechanism of injury, fracture location, and surgical complications. The follow-up ranged from 3 days to 5 years, with an average follow-up of 74 days. Among the study group, 158 patients (84 percent) were men and 31 (16 percent) were women. Most of the patients were between the ages of 21 and 30 years (Fig. 1). As in other retrospective reviews of facial trauma in the urban setting, interpersonal violence was the primary mechanism of injury. 1 Ninety-one patients (48.1 percent) sustained injuries in this manner. The remaining injuries were caused by automobile crashes, falls, automobilepedestrian accidents, and contact sports (Fig. 2). A history of drug and/or alcohol abuse was reported by many patients. The most common fractures treated were of the mandible (Table I). These 140 fractures constituted 47.6 percent of the group, followed by (in decreasing frequency) fractures of the zygoma and fractures of the orbit (Fig. 3). FIG. 2. Mechanisms of injury. TABLE I Fracture Location Location No. (%) Mandible 140(47.62) Zygoma 51(17.35) Orbit 33(11.22) Nose 19(6.46) Frontal sinus 15(5.1) Nasoethmoidal-orbital 14(4.76) Palate 9(3.06) Le Fort I 4(1.36) Le Fort II 4(1.36) Le Fort III 4(1.36) Panfacial 1(0.34) Total 294(100) 43e FIG. 1. Facial trauma age distribution in years. During the period of review, techniques of exposure and fixation were uniform, as a single faculty surgeon supervised all procedures. Noncomminuted parasymphyseal and body fractures of the mandible were all treated intraorally using miniplate fixation along the ideal lines of osteosynthesis. Mandibular angle fractures were treated intraorally by placing a single matrix or strut miniplate. Comminuted fractures and fractures involving substantial bone loss were treated with locking reconstruction plates. All subcondylar fractures were treated using maxillomandibular fixation. Orbitozygomatic fractures were exposed using incisions in the gingivobuccal sulcus, transconjunctivally in the lower eyelid and through a lateral extension of the supratarsal fold in the

3 44e PLASTIC AND RECONSTRUCTIVE SURGERY, September 1, 2005 FIG. 3. Facial fracture locations. upper eyelid. A coronal incision was only used if the infraorbital rim and zygomatic buttresses were so comminuted that adequate alignment required arch visualization. A Carol-Gerard screw was used for disimpaction and alignment of the fracture in all cases. All orbital floor and medial wall fractures were treated with synthetic implants, including titanium meshes, resorbable implants, and high-density porous polyethylene. Exposure was exclusively by means of a transconjunctival approach. RESULTS During the follow-up period, 23 complications were noted among the 294 fractures, yielding a 7.8 percent overall complication rate. Twenty-one of the complications required operative repair, whereas two were managed with nonoperative therapy. Problems after mandibular fracture repair contributed to only 13 percent of the 23 complications. Among the 13 patients with complications related to repair of a mandible fracture, six experienced a postoperative infection. The cause was most frequently hardware failure, treatment of which consisted of removal of hardware and replacement by more rigid fixation. The remaining complications consisted of malocclusion, intraoral plate exposure, orofacial fistula, trismus, and a failed free fibula flap. Numbness of the lower lip was not evaluated. There were no complications requiring operative repair within the subset of patients who received treatment for subcondylar fractures, including no cases of malocclusion. Complications from orbital fracture repair contributed to five of the 23 complications. Enophthalmos (acute or delayed) was seen in three of the 33 orbital fracture repairs, resulting in a 9 percent incidence of enophthalmos following orbital fracture repair. The technique for correction of postoperative enophthalmos involved repeated reconstruction with either titanium or porous polyethylene implants. No patient demonstrated diplopia at the time of last follow-up. After repair of frontal sinus fractures, one patient experienced an infection of the calcium phosphate bone cement used that required removal, and another patient developed postoperative sinusitis that was effectively treated with oral antibiotics. Of the 14 patients who experienced nasoethmoidal-orbital fractures, one patient experienced persistent telecanthus. This was repaired with repeated transnasal wiring. Table II lists all the complications that were encountered and their subsequent management. Table III lists the complication rates by fracture location. DISCUSSION Since the initial descriptions by Michelet and others of internal fixation with small plates and screws for facial fractures, surgeons have developed a myriad of techniques to accompany the ongoing development of commercially available materials. 2 These methods are often variations on traditional surgical approaches that have been adjusted to appropriately fit specific clinical situations. An examination of the data demonstrates that the most common fracture treated was of the mandible (47.62 percent, n 140). Our techniques vary depending on the type (simple versus comminuted) and location of the fracture. In accordance with the principles described by Champy et al., miniplate fixation along the ideal lines of osteosynthesis was the preferred form of stabilization for simple fractures. 3 When used in the appropriate situ-

4 Vol. 116, No. 3 / FACIAL FRACTURES IN A TRAUMA CENTER 45e TABLE II Fracture Repair, Complications, and Correction Fracture Repair Complications Correction Mandible Intraoral plate exposure Pectoralis flap coverage Mandible body Infected ORIF Removal of infected tension band Mandible body Infected ORIF Extraction of retained tooth roots Mandible body Infected ORIF I & D, removal of loose screw Mandible angle Malocclusion Removal of strut plates, MMF Mandible angle Orofacial fistula Closure of fistula Mandible parasymphysis Infected ORIF Removal of 2.0 plate, replaced with 2.4 LR Mandible angle Infected ORIF Third molar extraction Mandible angle Infected ORIF Third molar extraction and LR plate replacement Mandible angle Screws in fracture line Repeat ORIF Mandible body Failed free fibula to reconstruct lateral defect Repeat free fibula Mandible Soft-tissue infection Debridement and antibiotic therapy Mandible angle/subcondylar Trismus Oral exercises Orbital floor Delayed enophthalmos Medpor wedge Orbital floor Entropion Palatal graft for entropion Orbital floor Extrusion of hardware Removal of hardware Orbital floor Lower lid retraction Massage Orbital floor Enophthalmos Repeat ORIF with titanium mesh Frontal sinus fracture Infected Mimex Removal Frontal sinus Sinusitis Antibiotic therapy Orbitozygoma fracture Enophthalmos Medpor wedge Zygomatic arch fracture Malunion Osteotomy and replating NOE Telecanthus Repeat ORIF and transnasal wiring ORIF, open reduction and internal fixation; NOE, nasoethmoidal-orbital. ations, there can be no question that miniplate fixation results in a lower incidence of malocclusion than does fixation with larger reconstruction plates. These smaller plates, typically accommodating screws 2 mm in diameter, do not have to be precisely adapted to the mandibular contour, as do larger plates. Of course, they are not applicable to all mandibular fractures. The greater the instability present in the mandible, the more prone one should be to use larger plates. Comminuted fractures, fractures involving substantial bone loss, and multiple mandibular fractures should cause one to consider using larger reconstruction plates (Fig. 4). When such plates are chosen, however, the surgeon should typically use locking plates. 4,5 Locking reconstruction plates function in that the screw is threaded into the plate TABLE III Fracture Location, Complications, and Complication Rate by Location Fracture Location Complications (% of total, n 23) Complication Rate by Location (%) Mandible 13(56.52) 9.29%(n 140) Orbital floor 5(21.74) 15.15%(n 33) Frontal sinus 2(8.70) 13.33%(n 15) Zygoma 2(8.7) 3.92%(n 51) NOE 1(4.35) 7.14%(n 14) NOE, nasoethmoidal-orbital. FIG. 4. Locking plate. at the end of its insertion, preventing the bone from being pulled up to a maladapted plate. In essence, the plate acts as a form of internal external fixator. Consequently, just as with miniplates, one need not contour the plate exactly to the shape of the underlying mandible. These are less likely to result in a malocclusion. In addition, loose screws should theoretically never be seen, as the screw is dependent on the plate itself for stability and not its contact with the bone. Another important point is the appropriate treatment of subcondylar fractures. There are many advocates of open reduction. Most point out that the results of the open approach are better with respect to range of opening, diminished deviation on opening, and restoration of the mandibular contour at rest. 6 8,11 Although this may be the case, the real question is

5 46e PLASTIC AND RECONSTRUCTIVE SURGERY, September 1, 2005 whether or not the additional morbidity of the open approach is worth it. That is, even though a patient treated in a closed fashion for a subcondylar fracture often deviates with maximal opening and has some loss of definition of the jawline at rest, we have yet to have a patient complain of this. This must be contrasted with a potential facial nerve injury secondary to opening a subcondylar injury. With most open approaches to reduce and plate the condylar region, facial nerve injury is the primary concern. Even though this is typically temporary, the surgeon cannot know this immediately postoperatively. Many of these patients must be followed for months before recovery is apparent. In addition, recovery of the nerve is not always complete, with ongoing facial asymmetry being problematic. Although there has been a great deal of interest in the endoscopic approach, this has a very steep learning curve. 9,10 As such, for all but the most experienced surgeons, it is entirely appropriate to treat the majority of these patients in maxillomandibular traction of some sort. The type of intermaxillary fixation and its duration are entirely dependent on the patient s occlusion. In those cases in which, once all other mandibular fractures are fixated, the occlusion is at its preinjury level despite the subcondylar injury, no further treatment or intermaxillary elastics are quite acceptable. However, when the occlusion is still quite disordered following fixation of the other mandibular fractures, strong consideration should be given to maxillomandibular wires. Given the relative unreliability of many patients with these injuries, elastics should generally not be trusted. The duration of intermaxillary fixation depends entirely on the level of the subcondylar fracture and the severity of the malocclusion being treated. Rarely, however, should it exceed 3 to 4 weeks. It is important to note that intermaxillary fixation never truly reduces the fracture. Rather, it forces the patient to functionally adapt the bite to the existing subcondylar displacement, restoring the preinjury occlusion. This is not to say, however, that no subcondylar fracture should be treated in an open fashion. 11 In any patient in whom intermaxillary fixation is contraindicated, such as those with a severe poorly controlled seizure disorder, open reduction should be strongly considered. In addition, in patients with massive panfacial injuries with bilateral subcondylar fractures, open reduction of one side should be considered to establish the posterior facial height. We must emphasize that no subcondylar injuries in this series were treated in an open fashion. Mandibular angle fractures must be given special attention. These are some of the most difficult fractures to treat successfully. There are several issues to consider, including difficulty with intraoral visualization and the problem of third molar management. Although the majority of uncomplicated angle fractures may be managed using intraoral incisions and transbuccal drill and screw placement, consent should be given by all patients for an external incision should the intraoral approach prove too problematic. When placing fixation using the intraoral approach, we have found the matrix or strut plate to be very useful (Fig. 5). Generally the plate is placed in the midportion of the angle and secured using 6-mm-long screws that are 2 mm in diameter. The plate itself needs no contouring and provides excellent stabilization. With respect to the management of third molars, the literature is replete with different viewpoints The only real benefit to retention of this tooth is in its contribution to the stability of the angle. When large plates (2.4 mm) are used for fracture fixation, there is relatively little benefit to retaining the molar. However, when the intraoral approach is used and small plates are applied, serious consideration should be given to maintaining the tooth if possible because it adds stability. In general, the novice surgeon should err on the side of removing the molar when there is any question regarding the condition of the periodontal tissues or possible damage to the molar itself. FIG. 5. Mandibular strut/matrix plate rigidly fixating a mandibular angle fracture (note that the mandibular third molar has been removed).

6 Vol. 116, No. 3 / FACIAL FRACTURES IN A TRAUMA CENTER Two infections in this series occurred in angle fractures with third molars left in position. With respect to malar injuries, the most common severe complication seen was enophthalmos. 16,17 Even in the best of hands, this is not an uncommon complication. When teaching residents the technique for correcting the fracture, there are several important points to emphasize. First, the vast majority of these injuries can be corrected without a coronal incision. The only instance in which the coronal incision is needed is when there is so much comminution at the level of the infraorbital rim and the zygomaticomaxillary buttress that these two cannot be used for accurate positioning of the fragment. In these situations, visualization and alignment of the zygomatic arch are helpful. Perhaps the most important point to emphasize in teaching reduction and fixation of malar fractures is the need to overcorrect the position of the globe (Fig. 6). At the end of procedure, the globe on the affected side should project more anteriorly than the unaffected globe. Given the swelling induced by the injury and the operation, the eye on the operative side must project more. If at the end of the procedure the globes are symmetric, one should expect postoperative enophthalmos. If the overcorrection is not seen at the end of the procedure, the surgeon has several options. One option is to remove the fixation and reposition the malar fragment. However, if the surgeon is confident in the positioning of the zygoma, the second option is to overcorrect the orbital floor and intraorbital volume. As the vast majority of these injuries do require repair of the orbital floor, this may be the source of the error. One should not hesitate to add extra volume to the orbital cone should the globe not be in an appropriate position at the end of the procedure. In this series, only one of 51 47e malar fractures developed clinically significant enophthalmos using this philosophy. Another important technical aspect facilitating correction of the malar position is the use of a Carol-Gerard screw (Fig. 7). This instrument is available as a self-drilling screw that may be placed through the lower eyelid incision into the zygoma, allowing it to be used essentially as a handle. One may use this to both disimpact the zygoma and to position it much like a joystick for fixation. This greatly facilitates ease of handling of the zygoma during these procedures. In isolated orbital injuries, the same issues apply with respect to enophthalmos. 17,18 At the end of the procedure to reconstruct the fractured walls, the orbital volume should be overcorrected. The globe should project more anteriorly. If it does not, adding additional volume to the orbital cone is mandatory to ensure appropriate position postoperatively. Only one of the 33 patients with orbital floor injuries developed clinically significant enophthalmos in this series. On repeated scanning, the enophthalmos in this case was thought to be related solely to inaccurate reconstruction resulting in an increase in orbital volume. Another major issue in teaching techniques of orbital surgery is to studiously avoid the transcutaneous approaches to the orbital floor. There can be no question when the literature and personal experience are reviewed that lower eyelid retraction is much more common when transcutaneous lower eyelid approaches are used for facial trauma (Fig. 8). 19 The one exception may be a subtarsal approach to the lower eyelid in which the skin incision is placed low on the eyelid in a preexisting crease. 20 Although this may be applicable to older patients, it should generally be avoided for the more common younger patient with facial FIG. 6. Overcorrection of the right globe consistent with anatomical reconstruction of an orbital floor fracture.

7 48e PLASTIC AND RECONSTRUCTIVE SURGERY, September 1, 2005 FIG. 7. Carol-Gerard screw. FIG. 8. Lower eyelid retraction following a subciliary incision for repair of orbital floor fracture. trauma, because of the visibility of the scar. We prefer the transconjunctival approach. It substantially lowers the risk of retraction and completely avoids a visible scar. Unless corneal exposure or significant globe irritation is present, it is best to manage these cases conservatively with massage. The vast majority of cases will resolve. If after 4 to 6 months there is still a substantial problem, operative intervention should be considered. All patients in this series were treated exclusively using the transconjunctival approach. Only one case of lower eyelid retraction (an entropion) required operative correction. In the majority of patients, a lateral canthotomy is preferable to improve visualization of the orbital floor. Although fracture repair is possible without this, the inexperienced clinician is at a disadvantage performing the procedure. At the end of the procedure, a canthoplasty is typically required. Although simple reattachment of the lower lid to the upper lid can occasionally suffice to produce an acceptable appearance to the canthal angle, it is safer to perform a canthoplasty. This does require some degree of skill. The point of fixation of the lateral canthus should be to the periosteum on the inner aspect of the orbital rim. It is helpful to use a very small curved needle, such as a P-2, to facilitate this. Another important aspect of training residents is in the choice of implant for reconstruction of the orbit. Although a great deal has been written about the use of a bone graft in floor reconstruction, this requires a donor site and in some cases a degree of shaping of the graft. Although this technique works quite well, it is more difficult and offers little in the way of advantages over synthetic implants. There are a vast array of implants for floor and medial wall reconstruction that function very well, with a negligible rate of infection. Among these are titanium meshes, resorbable implants, and highdensity porous polyethylene For smaller defects, the resorbable materials are quite nice, as they slide over the defect easily without catching any of the periorbita, as titanium has a tendency to do. However, for larger defects of the orbital floor, titanium offers excellent support and is easy to contour. It may be easier for the novice surgeon to contour these implants preoperatively using a standard skull model and then subsequently sterilize the implant and cut it to the appropriate size intraoperatively. The orbital floors of most adults are similar in shape, and this may prevent the surgeon from grossly maladapting the implant. In this series, none of the orbital floor prostheses used had to be removed. It is also important to emphasize the need to dissect the floor defect cephalically, not straight posteriorly. As the orbital floor inclines superiorly, frequently the posterior ledge of the defect is higher than anticipated. Dissecting directly posterior may result in the implant essentially being placed in the maxillary sinus (Fig. 9). When the surgeon encounters difficulty in locating the posterior aspect of the defect, it may be helpful to place an elevator into the defect and back to the posterior wall of the maxillary sinus. The elevator can then be lifted up against the undersurface of the posterior aspect of the remaining floor, to help the surgeon define the defect. CONCLUSIONS This experience at a high-volume level I trauma center with residents as the primary physicians has confirmed that facial trauma surgery may be undertaken with an acceptably low complication rate. The above technical points facilitate performance of fixation of the

8 Vol. 116, No. 3 / FACIAL FRACTURES IN A TRAUMA CENTER 49e FIG. 9. Orbital floor implant in the maxillary sinus. facial skeleton by relatively inexperienced surgeons. Although there are many ways for the experienced physician to approach facial fractures, some of the techniques do require a greater degree of skill. As with any reconstructive procedure, the specifics of the patient s fracture pattern are the ultimate guide to the appropriate technique. Larry H. Hollier, M.D. Clinical Care Center, Suite Fannin Street, MC CC Houston, Texas larryh@bcm.tmc.edu ACKNOWLEDGMENTS Financial support for this study was provided by Walter Lorenz Surgical, Inc. Dr. Larry H. Hollier, Jr., also receives additional financial support from Walter Lorenz Surgical, Inc., for his research team. REFERENCES 1. Scherer, M., Sullivan, W. G., Smith, D. J., Jr.,Phillips, L. G., and Robson, M. C. An analysis of 1423 facial fractures in 788 patients at an urban trauma center. J. Trauma 29: 388, Michelet, F. X., Deymes, J., and Dessus, B. Osteosynthesis with miniaturized screwed plates in maxillofacial surgery. J. Maxillofac. Surg. 1: 79, Champy, M., Lodde, J. P., Schmitt, R., et al. Mandibular osteosynthesis by miniature screwed plates via buccal approach. J. Maxillofac. Surg. 6: 14, Ellis, E., and Graham, J. Use of a 2.0mm locking plate/ screw system for mandibular fracture surgery. J. Oral Maxillofac. Surg. 60: 642, Herford, A. S., and Ellis, E. Use of a locking reconstruction bone plate/screw system for mandibular surgery. J. Oral Maxillofac. Surg. 56: 1261, Yang, W. G., Chen, C. T., Tsay, P. K., and Chen, Y. R. Functional results of unilateral mandibular condylar process fractures after open and closed treatment. J. Trauma 52: 498, Worsaae, N., and Thorn, J. J. Surgical versus nonsurgical treatment of unilateral dislocated low subcondylar fractures: A clinical study of 52 cases. J. Oral Maxillofac. Surg. 52: 353, Ellis, E., McFadden, D., Simon, P., and Throckmorton, G. Surgical complications with open treatment of mandibular condylar process fractures. J. Oral Maxillofac. Surg. 58: 950, Chen, C. T., Lai, J. P., Tung, T. C., and Chen, Y. R. Endoscopically assisted mandibular subcondylar fracture repair. Plast. Reconstr. Surg. 103: 60, Lee, C., Mueller, R., Lee, K., and Mathes, S. Endoscopic subcondylar fracture repair: Functional, aesthetic, and radiographic outcomes. Plast. Reconstr. Surg. 102: 1434, Zide, M. F., and Kent, J. N. Indications for open reduction of mandibular condyle fractures. J. Oral Maxillofac. Surg. 41: 89, Fuselier, J. C., Ellis, E. E., and Dodson, B. Do mandibular third molars alter the risk of angle fracture? J. Oral Maxillofac. Surg. 60: 515, Halmos, D. R., Ellis, E. E., and Dodson, T. B. Mandibular third molars and angle fractures. J. Oral Maxillofac. Surg. 62: 1076, Meisami, T., Sojat, A., Sandor, G. K., Lawrence, H. P., and Clokie, C. M. Impacted third molars and risk of angle fractures. Int. J. Oral Maxillofac. Surg. 21: 140, Chan, D. M., Demuth, R. J., Miller, S. H., and Jastak, J. T. Management of mandibular fractures in unreliable patient populations. Ann. Plast. Surg. 13: 298, Souyris, F., Klersy, F., Jammet, P., and Payrot, C. Malar bone fractures and their sequelae: A statistical study of 1393 cases covering a period of 20 years. J. Craniomaxillofac. Surg. 17: 64, Hosal, B. M., and Beatty, R. L. Diplopia and enophthalmos after surgical repair of blowout fractures. Orbit 21: 27, Kawamoto, H. K. Late posttraumatic enophthalmos: A correctable deformity? Plast. Reconstr. Surg. 69: 423, Patel, P. C., Sobota, B. T., Patel, N. M., Greene, J. S., and Millman, B. Comparison of transconjunctival versus subciliary approaches for orbital fractures: A review of 60 cases. J. Craniomaxillofac. Surg. 4: 17, Rohrich, R. J., Janis, J. E., and Adams, W. P., Jr. Subciliary versus subtarsal approaches to orbitozygomatic fractures. Plast. Reconstr. Surg. 111: 1708, Hollier, L. H., Rogers, N., Berzin, E., and Stal, S. Resorbable mesh in the treatment of orbital floor fractures. J. Craniofac. Surg. 12: 242, Jacono, A. A., and Moskoowitz, B. Alloplastic implants for orbital wall reconstruction. Facial Plast. Surg. 16: Ellis, E., and Tan, Y. Assessment of internal orbital reconstruction for pure blowout fractures: Cranial bone grafts versus titanium mesh. J. Oral Maxillofac. Surg. 61: 442, 2003.