- Email: [email protected]
Results in rigid internal fixation of highly comminuted fractures of the mandible
Abstract Session VII: Anesthesia and Trauma
These data suggest that although peak latencies vary
significantly among patients, that an individual patient can reliably serve as their own control with regard to the predicted latency of the contralateral side. Variation from these values in states of pathology and under the influence of local anesthesia is under current investigation. Departmental funding provided
binding was seen in the untransfected negative control. The binding decreased appropriately in serial dilutions. We have, therefore, been successful in transfecting foreign DNA into cultured human keratinocytes. This method can now be used as a cytological marker in future grafting experiments. References Feinberg, S.E. et al.: J Oral Maxillofac Surg (in press) Brash, D.E. et al.: Mol Cell Biol7:2031, 1987
Transfection of Plasmid DNA into Human Keratinocytes as a Cytological Marker Mark E. Wohlford, DDS, The Ohio State Univ., 305 W. 12th Ave., Columbus, OH 43210 (Shuler, C.F., Feinberg, S.E.) We have recently developed an in vitro full-thickness oral mucosal equivalent (FTOME) suitable for intraoral grafting. The FTOME consisted of cultured oral epithelial cells seeded on a bilaminated dermal equivalent comprised of Type I and Type II cross-linked collagen matrix. Trials in dogs showed that the grafted FTOME enhanced wound epithelialization. However, the source of the re-epithelializing cells was not well identified, being either from surrounding host or grafted cultured epithelial cells. We have developed a technique that will allow us to incorporate a unique DNA sequence marker into cultured human epithelial cells. These cells can then be identified in vivo after grafting into the wound site by in situ hybridization techniques. Methods for transfecting foreign DNA into eukaryotic cells have recently been developed. Keratinocytes have shown to be difficult cells to culture and transfect. Recently a lab was able to get stable incorporation of DNA into human bronchial epithelium. We have used their methods to transfect a synthetic bacterial plasmid, pBR 322, into human keratinocytes. Keratinocytes were grown from primary outgrowth cultures. Cells were harvested and 1 x lo6 cells plated into a 25 cm2 flask. Plasmid DNA was precipitated with strontium chloride and allowed to settle onto the cells. The DNA was “pushed” into the cells by brief treatment with glycerol. Cells were harvested at confluency one week later. DNA was isolated from transfected and untransfected control cells, by freeze thawing, digesting with proteinase K, and then dissolving in hot NaI. The denatured DNA was immobilized onto nitrocellulose filters along with plasmid DNA as a positive control. Plasmid DNA was identified by 32P labeling 1 ug of pBR322 DNA by nick translation. This was then denatured and hybridized to the filter. The filter was washed and radioactivity detected by autoradiography. Results showed hybridization to both the positive control pBR322 DNA and the transfected cells. No AAOMS
.
1989
Funding provided by The Ohio State University
Results in Rigid Internal Fixation of Highly Comminuted Fractures of the Mandible Leon A. Assael, DMD, Long Island Jewish Med. Ctr., Dept. of Dentistry, New Hyde Park, NY 11042 (Friedlich, J.J.) Highly cornminuted fractures of the mandible occur as a result of gunshot wounds and other large impact trauma. The successful treatment of these injuries has been mitigated by the risk of infection, non-union with loss of bone substance, and malunion with resulting malocclusion. While loss of blood supply to segments and wound contamination are known sources of these problems, recent investigations have concluded that interfragmentary mobility is the most significant source of post trauma morbidity. Hence, the use of fixation that supplies absolute rigidity and immediate function has been employed to attempt to reduce post trauma morbidity. The purpose of this investigation is to evaluate that hypothesis with regard to patients who sustained highly cornminuted fractures of the mandible. Seventeen patients presented with mandible fractures in whom the number of bony segments were too numerous to count on cursory examination. Four of these patients had sustained gunshot wounds. The remainder had other large impact injuries. All of the fractures were compound injuries. The scheme of treatment for each of the patients was to first place the patient into intermaxillary fixation to restore the occlusion or ridge relationship. A transcervical approach was used in all 17 cases. Lag screws and miniplates were employed to fix small segments to each other. A reconstruction plate was used to bridge the cornminuted segment and provide absolute stability. A total of 22, 2.7mm lag screws were used on 10 of 17 patients (mean 1.3, range O-5). A total of 6 miniplates with 32, 2.0mm screws were utilized on 6 patients. All 17 of the patients had reconstruction plated placed with a mean of .33 (range 2-4) 2.7mm screws placed in the proximal segment, and a mean of 3.8 (range 2-5), 2.7mm screws placed in the distal segment. A mean of 1.1 (range O-3) 2.7mm screws were placed through the plate and into 119
Abstract Session VII: Anesthesia and Trauma the comminuted segment. In two patients where the loss of bone substance was excessive, immediate iliac crest bone grafting was performed. All of the wounds were treated with a Hemovac suction drain. Perioperative antibiotics were used in all cases. All 17 patients were placed into immediate function and remained in function throughout the course of their treatment. In 2 of the 17 patients (12%), a postoperative malocclusion was observed. Three of the 17 patients (17%) had postoperative infections that resulted in nonunion. Both of these patients remained in function through their eventual reconstruction. We conclude that it is possible to effectively employ rigid internal fixation techniques permitting immediate function in the management of highly comminuted fractures of the mandible.
Assael, L. and Hammon, K.: A Comparison of Wire Osteosynthesis and Rigid Internal Fixation of Mandible Fractures. J Oral Maxillofac Surg, Nov. 1987 (abstract) Speissl, B.: Internal Fixation of the Mandible, Springer-Verlag, Berlin, 1989 No funding provided
Low Velocity Missile Injuries to the Mandible: Retrospective Analysis of 32 Cases Edward A. Neupert, DDS, Univ. of Texas Southwestern Med. Ctr., Div. of Oral Surgery, 5323 Harry Hines Blvd., Dallas, TX 75235 (Boyd, S.B.) Several reports are available describing the surgical management of gunshot wound injuries to the face, however, few investigations have examined outcome following therapy. The purpose of this retrospective study was to evaluate treatment outcome following low velocity missile injuries to the mandible. To assess the efficacy of therapy three areas were studied: 1) incidence and severity of post-treatment infection, 2) state of osseous healing, and 3) range of motion. Thirty-two patients who had been treated at Parkland Memorial Hospital for low velocity gunshot wounds to the mandible were included in the study. The study group was predominantly young adult (mean age = 26 years) males (81%). A small but significant number of patients presented with associated major vessel injury (9%) or respiratory distress necessitating intubation (16%) or tracheotomy (12%). In general, surgical treatment was dependent on site of injury and patients could be subdivided into one of two groups on this basis. Injuries occurring in the condyle-ramus-coronoid area (CRC) (n = 10) were treated by closed reduction and stabilized with maxillomandibular fixation. In contrast,
120
the majority of injuries occurring in the angle-bodysymphysis region (ABS) (n = 22) were managed by minimal dentoalveolar debridement, primary wound closure, and primary stabilization with either an extraskeletal appliance (Joe Hall Morris), internal fixation, or maxillomandibular fixation. In the CRC group no postoperative infections were observed and all patients went on to clinical union. Mean maximal incisal opening (MIO) for the group was 28mm. In ABS group where injuries involved the oral cavity, post-treatment infections occurred in 21% of the patients, however, most of these infections were localized to dentoalveolar structures and were managed by relatively simple measures (extraction or localized sequestrectomy). A minority of patients (18%) had a residual continuity defect, which was treated secondarliy by autogenous cortico-cancellous bone grafting. This treatment resulted in satisfactory osseous union in each case. MI0 achieved in the ABS group was 36mm. The results of this study indicate that for injuries localized to the CRC region closed reduction predictably leads to osseous healing without evidence of infection. In contrast, injuries involving the ABS region were associated with a higher rate of infection and continuity defects, however, the treatment approach of minimal dentoalveolar debridement and extraskeletal stabilization yielded osseous union in the majority of cases (72%). The poorest outcome variable for the entire group was mandibular hypomobility (maximal incisal opening, t40mm) which occurred in 63% of the patients. Future studies should address this problem, possibly through the use of more aggressive and longer duration physiotherapy.
References Walker, R.V. and Frame, J.W.: Civilian maxillofacial gunshot injuries. Int J Oral Surg. 13:263-277, 1984 Zide, M.F. and Epker, B.N.: Short-range shotgun wounds to the face. J Oral Surg 37:319-330,1979 Funding provided by Univ. of Texas SW Med Ctr-Div. of OMS
Orbital Floor Exploration in Zygomaticomaxillary Complex Fractures Christopher H. Brown, DDS, Univ. of Connecticut Health Ctr., Dept. of OMS, L7073, Farmington, CT 06032 (Hupp, J.R.) The zygomatico-orbital complex fracture (ZMC) is a common mid-facial injury, second in frequency only to nasal fractures, and accounts for 15% of all facial fractures. ZMC injury, by definition, involves the orbital floor with the possibility of associated occular and extraoccular soft tissue damage. ZMC fractures, therefore, present challenging diagnostic and reconstructive prob-
AAOMS
l
1989
These data suggest that although peak latencies vary
significantly among patients, that an individual patient can reliably serve as their own control with regard to the predicted latency of the contralateral side. Variation from these values in states of pathology and under the influence of local anesthesia is under current investigation. Departmental funding provided
binding was seen in the untransfected negative control. The binding decreased appropriately in serial dilutions. We have, therefore, been successful in transfecting foreign DNA into cultured human keratinocytes. This method can now be used as a cytological marker in future grafting experiments. References Feinberg, S.E. et al.: J Oral Maxillofac Surg (in press) Brash, D.E. et al.: Mol Cell Biol7:2031, 1987
Transfection of Plasmid DNA into Human Keratinocytes as a Cytological Marker Mark E. Wohlford, DDS, The Ohio State Univ., 305 W. 12th Ave., Columbus, OH 43210 (Shuler, C.F., Feinberg, S.E.) We have recently developed an in vitro full-thickness oral mucosal equivalent (FTOME) suitable for intraoral grafting. The FTOME consisted of cultured oral epithelial cells seeded on a bilaminated dermal equivalent comprised of Type I and Type II cross-linked collagen matrix. Trials in dogs showed that the grafted FTOME enhanced wound epithelialization. However, the source of the re-epithelializing cells was not well identified, being either from surrounding host or grafted cultured epithelial cells. We have developed a technique that will allow us to incorporate a unique DNA sequence marker into cultured human epithelial cells. These cells can then be identified in vivo after grafting into the wound site by in situ hybridization techniques. Methods for transfecting foreign DNA into eukaryotic cells have recently been developed. Keratinocytes have shown to be difficult cells to culture and transfect. Recently a lab was able to get stable incorporation of DNA into human bronchial epithelium. We have used their methods to transfect a synthetic bacterial plasmid, pBR 322, into human keratinocytes. Keratinocytes were grown from primary outgrowth cultures. Cells were harvested and 1 x lo6 cells plated into a 25 cm2 flask. Plasmid DNA was precipitated with strontium chloride and allowed to settle onto the cells. The DNA was “pushed” into the cells by brief treatment with glycerol. Cells were harvested at confluency one week later. DNA was isolated from transfected and untransfected control cells, by freeze thawing, digesting with proteinase K, and then dissolving in hot NaI. The denatured DNA was immobilized onto nitrocellulose filters along with plasmid DNA as a positive control. Plasmid DNA was identified by 32P labeling 1 ug of pBR322 DNA by nick translation. This was then denatured and hybridized to the filter. The filter was washed and radioactivity detected by autoradiography. Results showed hybridization to both the positive control pBR322 DNA and the transfected cells. No AAOMS
.
1989
Funding provided by The Ohio State University
Results in Rigid Internal Fixation of Highly Comminuted Fractures of the Mandible Leon A. Assael, DMD, Long Island Jewish Med. Ctr., Dept. of Dentistry, New Hyde Park, NY 11042 (Friedlich, J.J.) Highly cornminuted fractures of the mandible occur as a result of gunshot wounds and other large impact trauma. The successful treatment of these injuries has been mitigated by the risk of infection, non-union with loss of bone substance, and malunion with resulting malocclusion. While loss of blood supply to segments and wound contamination are known sources of these problems, recent investigations have concluded that interfragmentary mobility is the most significant source of post trauma morbidity. Hence, the use of fixation that supplies absolute rigidity and immediate function has been employed to attempt to reduce post trauma morbidity. The purpose of this investigation is to evaluate that hypothesis with regard to patients who sustained highly cornminuted fractures of the mandible. Seventeen patients presented with mandible fractures in whom the number of bony segments were too numerous to count on cursory examination. Four of these patients had sustained gunshot wounds. The remainder had other large impact injuries. All of the fractures were compound injuries. The scheme of treatment for each of the patients was to first place the patient into intermaxillary fixation to restore the occlusion or ridge relationship. A transcervical approach was used in all 17 cases. Lag screws and miniplates were employed to fix small segments to each other. A reconstruction plate was used to bridge the cornminuted segment and provide absolute stability. A total of 22, 2.7mm lag screws were used on 10 of 17 patients (mean 1.3, range O-5). A total of 6 miniplates with 32, 2.0mm screws were utilized on 6 patients. All 17 of the patients had reconstruction plated placed with a mean of .33 (range 2-4) 2.7mm screws placed in the proximal segment, and a mean of 3.8 (range 2-5), 2.7mm screws placed in the distal segment. A mean of 1.1 (range O-3) 2.7mm screws were placed through the plate and into 119
Abstract Session VII: Anesthesia and Trauma the comminuted segment. In two patients where the loss of bone substance was excessive, immediate iliac crest bone grafting was performed. All of the wounds were treated with a Hemovac suction drain. Perioperative antibiotics were used in all cases. All 17 patients were placed into immediate function and remained in function throughout the course of their treatment. In 2 of the 17 patients (12%), a postoperative malocclusion was observed. Three of the 17 patients (17%) had postoperative infections that resulted in nonunion. Both of these patients remained in function through their eventual reconstruction. We conclude that it is possible to effectively employ rigid internal fixation techniques permitting immediate function in the management of highly comminuted fractures of the mandible.
Assael, L. and Hammon, K.: A Comparison of Wire Osteosynthesis and Rigid Internal Fixation of Mandible Fractures. J Oral Maxillofac Surg, Nov. 1987 (abstract) Speissl, B.: Internal Fixation of the Mandible, Springer-Verlag, Berlin, 1989 No funding provided
Low Velocity Missile Injuries to the Mandible: Retrospective Analysis of 32 Cases Edward A. Neupert, DDS, Univ. of Texas Southwestern Med. Ctr., Div. of Oral Surgery, 5323 Harry Hines Blvd., Dallas, TX 75235 (Boyd, S.B.) Several reports are available describing the surgical management of gunshot wound injuries to the face, however, few investigations have examined outcome following therapy. The purpose of this retrospective study was to evaluate treatment outcome following low velocity missile injuries to the mandible. To assess the efficacy of therapy three areas were studied: 1) incidence and severity of post-treatment infection, 2) state of osseous healing, and 3) range of motion. Thirty-two patients who had been treated at Parkland Memorial Hospital for low velocity gunshot wounds to the mandible were included in the study. The study group was predominantly young adult (mean age = 26 years) males (81%). A small but significant number of patients presented with associated major vessel injury (9%) or respiratory distress necessitating intubation (16%) or tracheotomy (12%). In general, surgical treatment was dependent on site of injury and patients could be subdivided into one of two groups on this basis. Injuries occurring in the condyle-ramus-coronoid area (CRC) (n = 10) were treated by closed reduction and stabilized with maxillomandibular fixation. In contrast,
120
the majority of injuries occurring in the angle-bodysymphysis region (ABS) (n = 22) were managed by minimal dentoalveolar debridement, primary wound closure, and primary stabilization with either an extraskeletal appliance (Joe Hall Morris), internal fixation, or maxillomandibular fixation. In the CRC group no postoperative infections were observed and all patients went on to clinical union. Mean maximal incisal opening (MIO) for the group was 28mm. In ABS group where injuries involved the oral cavity, post-treatment infections occurred in 21% of the patients, however, most of these infections were localized to dentoalveolar structures and were managed by relatively simple measures (extraction or localized sequestrectomy). A minority of patients (18%) had a residual continuity defect, which was treated secondarliy by autogenous cortico-cancellous bone grafting. This treatment resulted in satisfactory osseous union in each case. MI0 achieved in the ABS group was 36mm. The results of this study indicate that for injuries localized to the CRC region closed reduction predictably leads to osseous healing without evidence of infection. In contrast, injuries involving the ABS region were associated with a higher rate of infection and continuity defects, however, the treatment approach of minimal dentoalveolar debridement and extraskeletal stabilization yielded osseous union in the majority of cases (72%). The poorest outcome variable for the entire group was mandibular hypomobility (maximal incisal opening, t40mm) which occurred in 63% of the patients. Future studies should address this problem, possibly through the use of more aggressive and longer duration physiotherapy.
References Walker, R.V. and Frame, J.W.: Civilian maxillofacial gunshot injuries. Int J Oral Surg. 13:263-277, 1984 Zide, M.F. and Epker, B.N.: Short-range shotgun wounds to the face. J Oral Surg 37:319-330,1979 Funding provided by Univ. of Texas SW Med Ctr-Div. of OMS
Orbital Floor Exploration in Zygomaticomaxillary Complex Fractures Christopher H. Brown, DDS, Univ. of Connecticut Health Ctr., Dept. of OMS, L7073, Farmington, CT 06032 (Hupp, J.R.) The zygomatico-orbital complex fracture (ZMC) is a common mid-facial injury, second in frequency only to nasal fractures, and accounts for 15% of all facial fractures. ZMC injury, by definition, involves the orbital floor with the possibility of associated occular and extraoccular soft tissue damage. ZMC fractures, therefore, present challenging diagnostic and reconstructive prob-
AAOMS
l
1989