The treatment of the fractured edentulous maxilla Mostafa Farmand, Arnulf Baumann
Dept. of Oral and Maxillofacial Surgery (Head." Prof. Dr Dr E. W. Steinhiiuser, DDS, AID), University of Erlangen-Nuremberg, Erlangen, Germany.
SUMMARY. The results of a follow-up of 13 out of 21 patients treated for fractures of the edentulous maxilla are presented. They were treated alternatively with craniofacial suspension wiring and with miniplate osteosynthesis. Better results are achieved by miniplate osteosynthesis. Depending on the general condition of the patient, a treatment scheme can be recommended. KEY W O R D S : Edentulous midface fractures-Craniofacial suspension- Miniplate osteosynthesis
INTRODUCTION
In our study, we aimed to examine the results of the different methods of treatment and to record a treatment scheme based on these results.
Fractures of the edentulous maxilla are seen less frequently than those of the mandible. In a series of 66 edentulous patients with midface fractures, only 6 % ( = 4 patients) occurred at the Le Fort I / I I / I I I levels (Zachariades et al., 1984). But in elderly patients over 65 years of age, fractures in the maxilla and mandible seem to be equally common (Falcone et al., 1990). There is little literature available concerning the treatment of fractures of the edentulous maxilla. Furthermore, the treatment of these fractures has changed during the past 30 years. In the past, most fractures were treated conservatively with external means of stabilization which was then replaced by cranial suspension wires. Nowadays, an exact anatomical reconstruction of the midface is possible in most cases by using miniplate osteosynthesis. This is to be applauded considering the increased life expectancy of elderly patients. Fractures occurring in the edentulous maxilla occur less frequently due to the absence of teeth through which the fracturing forces are usually directly transmitted to the maxilla. In addition, dentures provide some protection against fracture by absorbing part of the traumatic forces (Ailing and Osbon, 1988; Mason, 1990). On the other hand, the midfacial bones of elderly patients are brittle and less resistant to fracture due to atrophy. These bones break into more fragments than those of younger people (Schwenzer, 1970). So far, there are two reasons against extensive surgical procedures of maxillary fractures in edentulous patients : impaired general condition, as well as the extensively fragmented facial bones. Failure to treat often results in a disturbed intermaxillary relationship with retromaxillism and a potential short face. This has a negative impact on both the stability of the denture and the masticatory function, as well as on the appearance.
MATERIAL AND M E T H O D S In the period between 1979 and 1989 we had 21 cases of totally or almost edentulous maxilla with central and centrolateral midfacial fractures (Le Fort I / I I / III). An isolated fracture of the Le Fort III type did not occur. There were 5 Le Fort I, 10 Le Fort II and 6 Le Fort II/III type fractures. In 2 cases, it was associated with mandibular fractures. When the accidents happened, the patients had an average age of 61 years, ranging from 32 to 84 years. Seven out of 21 patients were female. The main cause of the fracture was a road accident (48 %). 20 % of the fractures resulted from syncope or circulatory trouble. The remainder of the patients were injured in assaults under the influence of alcohol or during timber felling. The type of fractures and their treatment is shown in Table 1. 11 patients were treated by miniplate osteosynthesis, most of them with the Steinhiiuser system (Steinhiiuser, 1982) and a few with the 3-Dplating system (Farmand, 1991), and 8 by craniofacial suspension wiring. Two patients were not treated at all. Not all patients could be followed-up. Five patients had died in the meantime, 3 could not be contacted. The other 13 patients (Table 2) appeared for investiTable 1 - Types of fracture and their treatment in all patients
Le Fort I Le Fort II Le Fort II/III
341
Miniplate
Craniofacial suspension
No treatment
2 6 3
2 3 3
1 1 0
342
Journal of Cranio-Maxillo-Facial Surgery
2 - Types of fracture and their treatment in the patients followed-up
Table
Le Fort I Le Fort II Le Fort II/III
Craniofacial
No
Miniplate
suspension
treatment
2
2
0
6 1
1 0
1 0
gation. The average age of these patients was 58 years, ranging from 32 to 84 years. In addition to the clinical examination, we took x-rays of the face in the Water's projection, as well as lateral views. The average period between treatment and the follow-up was 2.25 years. RESULTS All patients followed-up were quite satisfied with the results of the treatment. All patients had a maxillary denture without irritation of the mucous membrane.
Fig. 3 - Pre- and postoperative lateral cephalometric X-ray of a patient with a Le Fort-I fracture treated with miniplate osteosynthesis, Note the position of the maxilla after the operation.
Fig. 1 - Le Fort II- fracture treated with craniofacial suspension wiring. Water's projection.
Fig. 4 - Water's projection of the same patient after repositioning
and fixationof the maxillawith 3-D-plates. Four patients had a retromaxillism. Three of these patients had previously been treated only by stabilizing the denture to the maxilla with zygomatic arch suspension (monomaxillary fixation) and an infraorbital rim revision (Figs 1 and 2). One patient could not be treated due to his poor general condition. In this case the retromaxillism was compensated by the denture. Nine maxillary fractures, which were reduced and fixed by using miniplates, showed a clinically correct position of the upper jaw with a good intermaxillary relationship in the lateral cephalogram (Figs 3 and 4). DISCUSSION
Fig. 2 - Lateral cephalometric X-ray showing retromaxillism in a patient treated by craniofacial suspension.
Little literature is available concerning the results of treatment of edentulous midfacial fractures compared with fractures occurring in the edentulous mandible.
The treatment of the fractured edentulous maxilla Table 3 - Treatment scheme for fractures of the edentulous
maxilla 1.
No displacement
2.
Displacement of the maxilla patient in poor general condition Le Fort I- level Le Fort II/III level
Soft diet for 2-3 weeks incorporation of dentures
No active therapy later: Le Fort-I osteotomy Minimal therapy, repositioning of nose and orbital rim, later: Le Fort-l-osteotomy
Displacement of the maxilla patient in good general condition Le Fort I/II/III level
Miniplate osteosynthesis in younger patients eventually with simultaneous preprosthetic surgery
Midfacial fractures in elderly persons are caused mainly by road accidents, while mandibular fractures are due to a fall or assault. If the maxilla is not displaced, there is no need for stabilization, because there will be no facial elongation (Joy et al., 1969). Displaced midfacial fractures, which are not treated, will usually result in retromaxillism (as could be seen in our patients), or in severe cases in a dishface deformity. As a consequence there will be some problems in providing a new denture. In addition to the functional disadvantage there are also aesthetic problems to be considered. In these cases a Le Fort-Iosteotomy is the method of choice for the correction of the malocclusion caused by a retrodisplaced maxilla (Obwegeser, 1969; Kennett and Kernahan, 1970). The follow-up of patients who were treated only by zygomatic wire suspension showed less positive results compared with patients treated with miniplate osteosynthesis. Similar results were shown by Zisser and Eskici (1973). Their 3 cases which were treated by intraskeletal suspension of the maxilla and intermaxillary fixation also showed retromaxillism. Later on the occlusion was prosthodontically compensated. Advantages of craniofacial suspension wiring are its rapid application and easy handling. The traction forces of fronto-maxillary and zygomatic-maxillary suspension wires, however, pull the maxilla caudally, even if beforehand it was placed in the correct position (Austermann and Meisel, 1975). If intermaxillary fixation with the application of splints is used, pressure ulcers can occur, which make early opening of the fixation necessary. The repositioned maxilla can easily be kept in place by means of miniplates. This prevents the midface from being displaced and shortened. This can be seen in our 9 patients who were treated by miniplate osteosynthesis. A wire osteosynthesis might be possible in some cases, but stabilization with miniplates is much easier and more effective. In addition, it is possible to reconstruct the midfacial buttresses simultaneously by open reduction. If an improvement of the situation for incorporation of the prosthesis is necessary, there are two
343
possibilities. In cases with soft tissue problems a modified submucous vestibuloplasty with so-called high retention sutures can be undertaken at the end of the operation (Farmand, 1986). The incision for the open reduction should therefore be made on the alveolar crest; thus interference with the vestibuloplasty can be avoided. If retromaxillism already exists before the accident, the fractured maxilla can be brought forward and fixed in a better relation to the mandible by means of miniplates. According to Freihofer (1989) the advanced edentulous maxilla is better stabilized by miniplates than by wire fixation. Also the relapse rate was lower with miniplate osteosynthesis. With the thin plates there is even the possibility of leaving the osteosynthesis material in situ without impairing denture function. According to our study, and the general condition of the patient and the severity of the midfacial fracture, the following procedures that should be carried out gradually, can be recommended (Table 3): 1. If the fractured maxilla is not displaced, in our opinion no operation is needed. Soft diet is to be prescribed for a period of 2-3 weeks and the dentures are to be worn. 2. If the maxilla is displaced at the Le Fort I level, the patient may be left untreated, if he is in a poor general condition or the bones are extremely fragmented. At a later date a conventional Le Fort-Iosteotomy might be necessary to improve the intermaxillary relationship. The same procedure is also possible in a Le Fort II/III fracture, when the patient's condition only allows minimal therapy. Then the nose and the orbital rim will be reduced, and a separate Le Fort-I osteotomy can be performed later. A discrepancy in the maxillary-mandibular relationship after minimal revision can of course also be compensated with dentures. But this can result in an increased resorption of the alveolar bone, so that a later maxillary osteotomy as a preposthetic procedure, is only delayed. 3. The miniplate osteosynthesis with thin plates is an alternative for all patients who can be operated on without risk. If necessary, in younger patients preprosthetic surgical procedures can be performed simultaneously, for instance a vestibuloplasty or an advancement of the maxilla.
CONCLUSION The treatment of fractures of the edentulous maxilla with craniofacial suspension wiring does not prevent retromaxillism. If fractures of the edentulous maxilla occur and the condition of the patient is satisfactory, operative treatment with miniplate osteosynthesis should be performed in order to prevent further deterioration of the intermaxillary relationship. Intermaxillary fixation is not necessary. This treatment will guarantee a good functional and aesthetic result in most cases. If the patient's condition contraindicates any operation, a
344 Journal of Cranio-Maxillo-Facial Surgery
Le Fort-I osteotomy to achieve a good position of the maxilla can be recommended at a later date. The results of this publication have been presented at the 10th congress of the European Association of Cranio-Maxillo-Facial Surgery, Brussels, 1990.
References Alling, C. C., D. B. Osbon : Maxillofacial trauma. Lea and
Febiger, Philadelphia, 1988 Austermann K. H., H. H. Meisel : Sp/itfolgen nach
Oberkieferfrakturen und die Behandlung von Konsolidierungsst6rungen. Fortsch, Kiefer Gesichtschir, 19 (1975) 198 Falcone, P. A., G. J. Haedicke, G. Brooks, P. K. Sullivan :
Maxillofacial fractures in the elderly: a comparative study. Plast. Reconstr. Surg. 86 (1990) 443 Farmand, M. : Horseshoe- sandwich-osteotomy of the edentulous maxilla as a preprosthetic procedure. J. Max. Fac. Surg. 14 (1986) 238 Farmand, M.." 3-D-osteosynthesis in craniofacial surgery. Abstr. Biannual meeting of the international society of craniomaxillofacial surgery 1991 Freihofer, H. P. : Stability after osteotomy of the edentulous maxilla. J. Max. Fac. Surg. 17 (1989) 306 Joy, E. D., L. E. McGaha. S. E. Bear: Facial elongation after
treatment of horizontal fracture of the maxilla without vertical suspension. J. Oral Surg. 27 (1969) 560 Kennett S., D. A. Kernahan: Maxillary osteotomy for correction of a traumatically retropositioned edentulous maxilla: report of a case. J. Oral Surg. 28 (1970) 905 Manson P. N.: Facial injuries In: McCarthy (ed.), Plastic surgery Vol 2, Saunders, Philadelphia (1990) 1028 Obwegeser, H. L. : Surgical correction of small or retrodisplaced maxilla. Plast. Reconstr. Surg. 43 (1969) 351 Schwenzer, N.: Die Mittelgesichtsfraktur beim alternden Menschen und ihre Behandlung. Dtsch Zahn~irztl. Z. 25 (1970) 132 Steinhduser E. W. : Bone screws and plates in orthognathic surgery. Int. J. Oral Surg. 11 (1982) 209 Zachariades N., D. Papavassiliou, D. Triantafyllou, E. Vairaktaris, J. Papademtriou, 3/I. Mezitis, A. Rapidis : Fractures of the
facial skeleton in edentulous patient. J. Max. Fac. Surg. 12 (1984) 262 Zisser G., A. Eskiei: Nachkontrollen und Ergebnisse der interfazialen Drahtaufh~ingung des Oberkeifers nach Adams. Osterr. Z. Stomatol, 70 (1973) 310
Priv. Doz. Dr Dr M. Farmand
Department of Oral and Maxillofacial Surgery University Erlangen- Nuremberg Glfickstr. I 1 D-8520 Erlangen Paper received 27 March 1992 Accepted 26 April 1992
Dept. of Oral and Maxillofacial Surgery (Head." Prof. Dr Dr E. W. Steinhiiuser, DDS, AID), University of Erlangen-Nuremberg, Erlangen, Germany.
SUMMARY. The results of a follow-up of 13 out of 21 patients treated for fractures of the edentulous maxilla are presented. They were treated alternatively with craniofacial suspension wiring and with miniplate osteosynthesis. Better results are achieved by miniplate osteosynthesis. Depending on the general condition of the patient, a treatment scheme can be recommended. KEY W O R D S : Edentulous midface fractures-Craniofacial suspension- Miniplate osteosynthesis
INTRODUCTION
In our study, we aimed to examine the results of the different methods of treatment and to record a treatment scheme based on these results.
Fractures of the edentulous maxilla are seen less frequently than those of the mandible. In a series of 66 edentulous patients with midface fractures, only 6 % ( = 4 patients) occurred at the Le Fort I / I I / I I I levels (Zachariades et al., 1984). But in elderly patients over 65 years of age, fractures in the maxilla and mandible seem to be equally common (Falcone et al., 1990). There is little literature available concerning the treatment of fractures of the edentulous maxilla. Furthermore, the treatment of these fractures has changed during the past 30 years. In the past, most fractures were treated conservatively with external means of stabilization which was then replaced by cranial suspension wires. Nowadays, an exact anatomical reconstruction of the midface is possible in most cases by using miniplate osteosynthesis. This is to be applauded considering the increased life expectancy of elderly patients. Fractures occurring in the edentulous maxilla occur less frequently due to the absence of teeth through which the fracturing forces are usually directly transmitted to the maxilla. In addition, dentures provide some protection against fracture by absorbing part of the traumatic forces (Ailing and Osbon, 1988; Mason, 1990). On the other hand, the midfacial bones of elderly patients are brittle and less resistant to fracture due to atrophy. These bones break into more fragments than those of younger people (Schwenzer, 1970). So far, there are two reasons against extensive surgical procedures of maxillary fractures in edentulous patients : impaired general condition, as well as the extensively fragmented facial bones. Failure to treat often results in a disturbed intermaxillary relationship with retromaxillism and a potential short face. This has a negative impact on both the stability of the denture and the masticatory function, as well as on the appearance.
MATERIAL AND M E T H O D S In the period between 1979 and 1989 we had 21 cases of totally or almost edentulous maxilla with central and centrolateral midfacial fractures (Le Fort I / I I / III). An isolated fracture of the Le Fort III type did not occur. There were 5 Le Fort I, 10 Le Fort II and 6 Le Fort II/III type fractures. In 2 cases, it was associated with mandibular fractures. When the accidents happened, the patients had an average age of 61 years, ranging from 32 to 84 years. Seven out of 21 patients were female. The main cause of the fracture was a road accident (48 %). 20 % of the fractures resulted from syncope or circulatory trouble. The remainder of the patients were injured in assaults under the influence of alcohol or during timber felling. The type of fractures and their treatment is shown in Table 1. 11 patients were treated by miniplate osteosynthesis, most of them with the Steinhiiuser system (Steinhiiuser, 1982) and a few with the 3-Dplating system (Farmand, 1991), and 8 by craniofacial suspension wiring. Two patients were not treated at all. Not all patients could be followed-up. Five patients had died in the meantime, 3 could not be contacted. The other 13 patients (Table 2) appeared for investiTable 1 - Types of fracture and their treatment in all patients
Le Fort I Le Fort II Le Fort II/III
341
Miniplate
Craniofacial suspension
No treatment
2 6 3
2 3 3
1 1 0
342
Journal of Cranio-Maxillo-Facial Surgery
2 - Types of fracture and their treatment in the patients followed-up
Table
Le Fort I Le Fort II Le Fort II/III
Craniofacial
No
Miniplate
suspension
treatment
2
2
0
6 1
1 0
1 0
gation. The average age of these patients was 58 years, ranging from 32 to 84 years. In addition to the clinical examination, we took x-rays of the face in the Water's projection, as well as lateral views. The average period between treatment and the follow-up was 2.25 years. RESULTS All patients followed-up were quite satisfied with the results of the treatment. All patients had a maxillary denture without irritation of the mucous membrane.
Fig. 3 - Pre- and postoperative lateral cephalometric X-ray of a patient with a Le Fort-I fracture treated with miniplate osteosynthesis, Note the position of the maxilla after the operation.
Fig. 1 - Le Fort II- fracture treated with craniofacial suspension wiring. Water's projection.
Fig. 4 - Water's projection of the same patient after repositioning
and fixationof the maxillawith 3-D-plates. Four patients had a retromaxillism. Three of these patients had previously been treated only by stabilizing the denture to the maxilla with zygomatic arch suspension (monomaxillary fixation) and an infraorbital rim revision (Figs 1 and 2). One patient could not be treated due to his poor general condition. In this case the retromaxillism was compensated by the denture. Nine maxillary fractures, which were reduced and fixed by using miniplates, showed a clinically correct position of the upper jaw with a good intermaxillary relationship in the lateral cephalogram (Figs 3 and 4). DISCUSSION
Fig. 2 - Lateral cephalometric X-ray showing retromaxillism in a patient treated by craniofacial suspension.
Little literature is available concerning the results of treatment of edentulous midfacial fractures compared with fractures occurring in the edentulous mandible.
The treatment of the fractured edentulous maxilla Table 3 - Treatment scheme for fractures of the edentulous
maxilla 1.
No displacement
2.
Displacement of the maxilla patient in poor general condition Le Fort I- level Le Fort II/III level
Soft diet for 2-3 weeks incorporation of dentures
No active therapy later: Le Fort-I osteotomy Minimal therapy, repositioning of nose and orbital rim, later: Le Fort-l-osteotomy
Displacement of the maxilla patient in good general condition Le Fort I/II/III level
Miniplate osteosynthesis in younger patients eventually with simultaneous preprosthetic surgery
Midfacial fractures in elderly persons are caused mainly by road accidents, while mandibular fractures are due to a fall or assault. If the maxilla is not displaced, there is no need for stabilization, because there will be no facial elongation (Joy et al., 1969). Displaced midfacial fractures, which are not treated, will usually result in retromaxillism (as could be seen in our patients), or in severe cases in a dishface deformity. As a consequence there will be some problems in providing a new denture. In addition to the functional disadvantage there are also aesthetic problems to be considered. In these cases a Le Fort-Iosteotomy is the method of choice for the correction of the malocclusion caused by a retrodisplaced maxilla (Obwegeser, 1969; Kennett and Kernahan, 1970). The follow-up of patients who were treated only by zygomatic wire suspension showed less positive results compared with patients treated with miniplate osteosynthesis. Similar results were shown by Zisser and Eskici (1973). Their 3 cases which were treated by intraskeletal suspension of the maxilla and intermaxillary fixation also showed retromaxillism. Later on the occlusion was prosthodontically compensated. Advantages of craniofacial suspension wiring are its rapid application and easy handling. The traction forces of fronto-maxillary and zygomatic-maxillary suspension wires, however, pull the maxilla caudally, even if beforehand it was placed in the correct position (Austermann and Meisel, 1975). If intermaxillary fixation with the application of splints is used, pressure ulcers can occur, which make early opening of the fixation necessary. The repositioned maxilla can easily be kept in place by means of miniplates. This prevents the midface from being displaced and shortened. This can be seen in our 9 patients who were treated by miniplate osteosynthesis. A wire osteosynthesis might be possible in some cases, but stabilization with miniplates is much easier and more effective. In addition, it is possible to reconstruct the midfacial buttresses simultaneously by open reduction. If an improvement of the situation for incorporation of the prosthesis is necessary, there are two
343
possibilities. In cases with soft tissue problems a modified submucous vestibuloplasty with so-called high retention sutures can be undertaken at the end of the operation (Farmand, 1986). The incision for the open reduction should therefore be made on the alveolar crest; thus interference with the vestibuloplasty can be avoided. If retromaxillism already exists before the accident, the fractured maxilla can be brought forward and fixed in a better relation to the mandible by means of miniplates. According to Freihofer (1989) the advanced edentulous maxilla is better stabilized by miniplates than by wire fixation. Also the relapse rate was lower with miniplate osteosynthesis. With the thin plates there is even the possibility of leaving the osteosynthesis material in situ without impairing denture function. According to our study, and the general condition of the patient and the severity of the midfacial fracture, the following procedures that should be carried out gradually, can be recommended (Table 3): 1. If the fractured maxilla is not displaced, in our opinion no operation is needed. Soft diet is to be prescribed for a period of 2-3 weeks and the dentures are to be worn. 2. If the maxilla is displaced at the Le Fort I level, the patient may be left untreated, if he is in a poor general condition or the bones are extremely fragmented. At a later date a conventional Le Fort-Iosteotomy might be necessary to improve the intermaxillary relationship. The same procedure is also possible in a Le Fort II/III fracture, when the patient's condition only allows minimal therapy. Then the nose and the orbital rim will be reduced, and a separate Le Fort-I osteotomy can be performed later. A discrepancy in the maxillary-mandibular relationship after minimal revision can of course also be compensated with dentures. But this can result in an increased resorption of the alveolar bone, so that a later maxillary osteotomy as a preposthetic procedure, is only delayed. 3. The miniplate osteosynthesis with thin plates is an alternative for all patients who can be operated on without risk. If necessary, in younger patients preprosthetic surgical procedures can be performed simultaneously, for instance a vestibuloplasty or an advancement of the maxilla.
CONCLUSION The treatment of fractures of the edentulous maxilla with craniofacial suspension wiring does not prevent retromaxillism. If fractures of the edentulous maxilla occur and the condition of the patient is satisfactory, operative treatment with miniplate osteosynthesis should be performed in order to prevent further deterioration of the intermaxillary relationship. Intermaxillary fixation is not necessary. This treatment will guarantee a good functional and aesthetic result in most cases. If the patient's condition contraindicates any operation, a
344 Journal of Cranio-Maxillo-Facial Surgery
Le Fort-I osteotomy to achieve a good position of the maxilla can be recommended at a later date. The results of this publication have been presented at the 10th congress of the European Association of Cranio-Maxillo-Facial Surgery, Brussels, 1990.
References Alling, C. C., D. B. Osbon : Maxillofacial trauma. Lea and
Febiger, Philadelphia, 1988 Austermann K. H., H. H. Meisel : Sp/itfolgen nach
Oberkieferfrakturen und die Behandlung von Konsolidierungsst6rungen. Fortsch, Kiefer Gesichtschir, 19 (1975) 198 Falcone, P. A., G. J. Haedicke, G. Brooks, P. K. Sullivan :
Maxillofacial fractures in the elderly: a comparative study. Plast. Reconstr. Surg. 86 (1990) 443 Farmand, M. : Horseshoe- sandwich-osteotomy of the edentulous maxilla as a preprosthetic procedure. J. Max. Fac. Surg. 14 (1986) 238 Farmand, M.." 3-D-osteosynthesis in craniofacial surgery. Abstr. Biannual meeting of the international society of craniomaxillofacial surgery 1991 Freihofer, H. P. : Stability after osteotomy of the edentulous maxilla. J. Max. Fac. Surg. 17 (1989) 306 Joy, E. D., L. E. McGaha. S. E. Bear: Facial elongation after
treatment of horizontal fracture of the maxilla without vertical suspension. J. Oral Surg. 27 (1969) 560 Kennett S., D. A. Kernahan: Maxillary osteotomy for correction of a traumatically retropositioned edentulous maxilla: report of a case. J. Oral Surg. 28 (1970) 905 Manson P. N.: Facial injuries In: McCarthy (ed.), Plastic surgery Vol 2, Saunders, Philadelphia (1990) 1028 Obwegeser, H. L. : Surgical correction of small or retrodisplaced maxilla. Plast. Reconstr. Surg. 43 (1969) 351 Schwenzer, N.: Die Mittelgesichtsfraktur beim alternden Menschen und ihre Behandlung. Dtsch Zahn~irztl. Z. 25 (1970) 132 Steinhduser E. W. : Bone screws and plates in orthognathic surgery. Int. J. Oral Surg. 11 (1982) 209 Zachariades N., D. Papavassiliou, D. Triantafyllou, E. Vairaktaris, J. Papademtriou, 3/I. Mezitis, A. Rapidis : Fractures of the
facial skeleton in edentulous patient. J. Max. Fac. Surg. 12 (1984) 262 Zisser G., A. Eskiei: Nachkontrollen und Ergebnisse der interfazialen Drahtaufh~ingung des Oberkeifers nach Adams. Osterr. Z. Stomatol, 70 (1973) 310
Priv. Doz. Dr Dr M. Farmand
Department of Oral and Maxillofacial Surgery University Erlangen- Nuremberg Glfickstr. I 1 D-8520 Erlangen Paper received 27 March 1992 Accepted 26 April 1992
