- Email: [email protected]
Poster 16
Scientific Poster Session tory pathways involved in complicated biological processes. This study was performed to identify the set of genes and to understand the molecular mechanisms that underlie the carcinogenesis and progression of oral cancer. Materials and Methods: By using a cDNA microarray representing 4,600 cDNA clusters, we studied the expression profiling in 7 oral cancer samples and the adjacent normal oral tissues from the same patients. The alterations in gene expression levels were confirmed by reverse-transcription PCR in randomly selected genes. Results: Genes that were differently expressed in more than 6 samples of oral cancer were identified. Eighty-one genes were up-regulated and 40 genes were down-regulated in the oral cancer. In cancer tissues, genes related to cell cycle, metabolism, cell structure, and signal transduction were mostly up-regulated. Furthermore, we identified a few putative tumor suppressor genes previously proposed by others. The RT-PCR analysis of randomly selected genes showed consistent findings with those in cDNA microarray. In addition, several genes were identified to be associated with lymph node metastasis comparing array data with clinicopathological ones. Conclusion: These results provide not only a new molecular basis for understanding biological properties of oral cancer, but also useful resources for future development of diagnostic markers and therapeutic targets for oral cancer. References Macfarlane G, Boyle P, Evstifeeva T, et al: Rising trends of oral cancer mortality among males worldwide; the return of an old public health problem. Cancer Causes Control 5:259, 1994 Parkin DM, Pisani P, Ferlay J: Estimate of the worldwide incidences of eighteen major cancers in 1985. Int J Cancer 54:594, 1993 Decker J, Goldstein JC: Risk factors in head and neck cancer. N Engl J Med 306:1151, 1982
POSTER 16 Digital Holography Aids Surgical Planning in Complex Maxillofacial Abnormalities Gerald Geldzahler, DDS, New York Medical College, Valhalla, NY 10595 (Shultz RA) Introduction: Complex maxillofacial pathology, developmental deformities, and injuries are often difficult to assess with conventional x-rays and CT/MR scans. This has prompted many oral and maxillofacial clinicians to utilize “3D” computer renderings in treatment planning. While these conventional techniques can be of great benefit, new digital holographic images which have been employed by other specialties produced from CT/MR scans offer real advantages over conventional techniques. AAOMS • 2003
Methods and Materials: Thin (1.25 to 3.0 mm) CT images (LightSpeed Plus, GE and Aquilion, Toshiba) were obtained on 12 diverse cases which presented to the Oral and Maxillofacial Surgery Department at Westchester Medical Center, Valhalla, NY, between August 2001 and December 2002. These data were used to produce white light holograms (Voxgram images; Voxel, Provo, Utah). CT scans were downloaded from our PACS (Synapse, FujiFilm) to a DICOM compatible software package (eFilm Workstation; Merge eFilm, Milwaukee, WI). This software running on a standard desktop computer (Dell Corp) includes a Simgram™ algorithm (Voxel), which allows cropping, windowing, and reorientation of CT/MR data to simulate a hologram, with ordering of actual holograms via Internet uploads to a centralized production facility. Within minutes the simulated holograms are previewed and the corresponding data transmitted for 24-hour turnaround of the physical 3-dimensional holographic film. Discussion: Many complex facial fractures are difficult to adequately visualize. Zygomaticomaxillary complex fractures with orbital floor involvement often require orbital floor exploration because of difficulty in radiographic assessment. Visualizing the full extent of pathological entities such as large tumors of the jaws is important in preoperative planning for resection and reconstruction. Severe craniomaxillofacial deformities clearly visualized help surgeons in treatment planning. All these conditions have been visualized holographically at Westchester Medical Center. Cases were chosen based on difficulty of diagnosis and visualization with conventional imaging techniques. We found that digital holograms in all cases provided superior visualization of anatomy and pathology over conventional imaging and display techniques in particular “3D” computer renderings. Results: The holographic images are life-sized, detailed, and accurate. Surgeons can interact with the image, which projects in front of the view box. They are transparent (one can see through bone), allowing visualization of complex anatomical relationships within a physical depth of 15 cm. They include a continuous 45° perspective horizontally and vertically, and can be flipped to view the anatomy from the reverse. Conclusions: Holograms allow in-depth views of the maxillofacial skeleton unavailable by any other means. These images are not just surface renderings as seen in typical computer-based 3D display. They are “sculptures” of light projecting out in space in front of the film into which surgical instruments can be placed during the planning process. This has provided us with an extremely valuable tool in the planning and evaluation of complex cases. 89
Scientific Poster Session References Schulz RA, Andre´ MP, Robertson DD, et al: Transmission holograms of tomographic data on 14⬙ x 17⬙ film. Med Physics 21:892, 1994 DiSaia J, Furnas D, Geil G, et al: Holograms for evaluating craniofacial problems & for planning craniofacial surgery. Proceedings of the Seventh International Congress of the International Society of Craniofacial Surgery, Monduzzi Editore, pp 91-93, October 1997
POSTER 17 Reconstruction of the Severely Atrophic Maxilla: A Retrospective Study Peter Gioulos, BSc, DDS, 909 Bay Street, Toronto, ON M5S 3K6 Canada (Clokie CML; Sandor GKB) Purpose: The removal of maxillary posterior teeth may lead to insufficient bone in the posterior maxilla for endosseous dental implant placement. This is due in part to the pneumatization of the maxillary sinuses. Different strategies for bone augmentation in the posterior maxilla have been attempted including techniques involving alloplastic, allogenic, and autogenous bone grafts. The objective of this investigation was to evaluate the efficacy of autogenous bone harvested from the iliac crest for subantral augmentation of the maxillary sinus and subsequently the ability of this site development strategy to allow for osseointegration. Materials and Methods: Fifty-four patients (90 sinuses) with posterior maxillary alveolar ridge Lekholm-Zarb bone quality classification of 4 were evaluated. Bone was harvested from the anterior iliac crest in 17 patients and from the posterior iliac crests in 37. Forty-two patients were additionally treated with platelet rich plasma (PRP) at the time of bone graft placement. Two hundred seven root form endosseous dental implants were placed 6 to 9 months after initial graft surgery. Pantomography was used to evaluate posterior maxillary alveolar ridge height preoperatively (T1), immediately postoperatively (T2), and at the time of dental implant insertion (T3). Results: Alveolar height was seen to increase at T2 by 14 mm with subsequent bone height loss at T3 during graft consolidation prior to implant insertion of 1.2 mm. The overall rate of osseointegration of the endosseous implants was found to be 94.7%. Eighteen patients experienced postoperative complications including soft tissue infection of the grafted site, implant failure, dehiscence of the grafted site, soft tissue infection of the donor site, sinus infection with fistulae, and seroma of the posterior hip donor site. Nine patients treated with PRP had bone cores harvested at the time of implant insertion and histomorphometric analysis revealed an average of 46.4% vital bone per core. No statistically significant differences in implant success were found with respect to gender, application of PRP, the different implant systems used, or donor site used. Conclusion: The 2 step approach to posterior maxillary reconstruction with bone graft harvest from the iliac 90
crest followed by dental implant placement at 6 to 9 months allows for predictable maxillary reconstruction and osseointegration. References Pejrone G, Lorenzetti M, Mozzati M, et al: Sinus floor augmentation with autogenous iliac bone block grafts: A histological and histomorphometrical report on the two-step surgical technique. Int J Oral Maxillofac Surg 13:69, 1998 Lekholm U, Wannfors K, Isaksson S, et al: Oral implants in combination with bone grafts: A 3-year retrospective multicenter system. Int J Oral Maxillofac Surg 28:187, 1999
POSTER 18 Maxillary Distraction by Intraoral Devices Patricia Lopez, DDS, Santa Rosa Maxillofacial Surgery Center, Centro Integral Santa Rosa, #105, Caracas, 1061 Venezuela (Figueroa F; Dominguez E; Guerrero CA) Purpose: Evaluate an intraoral device to bi- or 3-dimensionally reposition the maxilla by distraction osteogenesis, avoiding the use of bone grafts or heavy rigid fixation. Facial deformities were treated at different levels: Le Fort I, high Le Fort I, and modified Le Fort III were included in this study. Materials and Methods: Thirty-six patients (12 to 35 years old, average 18.4) were treated by maxillary advancement at different osteotomy levels. All the patients underwent a combined surgical-orthodontics treatment, and transverse, vertical, and anteroposterior movements were carefully evaluated. An intraoral dynaform appliance was utilized on either side, anchoraged to the zygomatic bone or to the pyramidal apophysis. The protocol used was: 7 days latency, 1 mm per day activation, and 90 days consolidation period. The minimal age to indicate the surgery was based on enough surgical space between the root of the canine (5 mm above the apex), the infraorbital nerve, and the lacrimal duct. Complete radiographs and photographs were obtained pre- and immediately postsurgery, 3 months after, at the appliance removal stage, and 6 months after braces were removed. Dental models in an articulator were taken before the surgery and after braces removal. Results: The maxilla was advanced 8 to 14 mm (average, 10.5), the canines were evaluated by pulp test with positive response at the braces removal stage, no teeth were damaged, and no epiphora or infraorbital nerve dysesthesia occurred. The dental occlusions were Class I with adequate overbite and overjet, with noncanted occlusal planes. Conclusions: The intraoral devices are ideal means to advance the maxilla in a bi-dimensional manner and may also be combined with maxillary widening in particular situations. This surgical approach eliminates the need for AAOMS • 2003
POSTER 16 Digital Holography Aids Surgical Planning in Complex Maxillofacial Abnormalities Gerald Geldzahler, DDS, New York Medical College, Valhalla, NY 10595 (Shultz RA) Introduction: Complex maxillofacial pathology, developmental deformities, and injuries are often difficult to assess with conventional x-rays and CT/MR scans. This has prompted many oral and maxillofacial clinicians to utilize “3D” computer renderings in treatment planning. While these conventional techniques can be of great benefit, new digital holographic images which have been employed by other specialties produced from CT/MR scans offer real advantages over conventional techniques. AAOMS • 2003
Methods and Materials: Thin (1.25 to 3.0 mm) CT images (LightSpeed Plus, GE and Aquilion, Toshiba) were obtained on 12 diverse cases which presented to the Oral and Maxillofacial Surgery Department at Westchester Medical Center, Valhalla, NY, between August 2001 and December 2002. These data were used to produce white light holograms (Voxgram images; Voxel, Provo, Utah). CT scans were downloaded from our PACS (Synapse, FujiFilm) to a DICOM compatible software package (eFilm Workstation; Merge eFilm, Milwaukee, WI). This software running on a standard desktop computer (Dell Corp) includes a Simgram™ algorithm (Voxel), which allows cropping, windowing, and reorientation of CT/MR data to simulate a hologram, with ordering of actual holograms via Internet uploads to a centralized production facility. Within minutes the simulated holograms are previewed and the corresponding data transmitted for 24-hour turnaround of the physical 3-dimensional holographic film. Discussion: Many complex facial fractures are difficult to adequately visualize. Zygomaticomaxillary complex fractures with orbital floor involvement often require orbital floor exploration because of difficulty in radiographic assessment. Visualizing the full extent of pathological entities such as large tumors of the jaws is important in preoperative planning for resection and reconstruction. Severe craniomaxillofacial deformities clearly visualized help surgeons in treatment planning. All these conditions have been visualized holographically at Westchester Medical Center. Cases were chosen based on difficulty of diagnosis and visualization with conventional imaging techniques. We found that digital holograms in all cases provided superior visualization of anatomy and pathology over conventional imaging and display techniques in particular “3D” computer renderings. Results: The holographic images are life-sized, detailed, and accurate. Surgeons can interact with the image, which projects in front of the view box. They are transparent (one can see through bone), allowing visualization of complex anatomical relationships within a physical depth of 15 cm. They include a continuous 45° perspective horizontally and vertically, and can be flipped to view the anatomy from the reverse. Conclusions: Holograms allow in-depth views of the maxillofacial skeleton unavailable by any other means. These images are not just surface renderings as seen in typical computer-based 3D display. They are “sculptures” of light projecting out in space in front of the film into which surgical instruments can be placed during the planning process. This has provided us with an extremely valuable tool in the planning and evaluation of complex cases. 89
Scientific Poster Session References Schulz RA, Andre´ MP, Robertson DD, et al: Transmission holograms of tomographic data on 14⬙ x 17⬙ film. Med Physics 21:892, 1994 DiSaia J, Furnas D, Geil G, et al: Holograms for evaluating craniofacial problems & for planning craniofacial surgery. Proceedings of the Seventh International Congress of the International Society of Craniofacial Surgery, Monduzzi Editore, pp 91-93, October 1997
POSTER 17 Reconstruction of the Severely Atrophic Maxilla: A Retrospective Study Peter Gioulos, BSc, DDS, 909 Bay Street, Toronto, ON M5S 3K6 Canada (Clokie CML; Sandor GKB) Purpose: The removal of maxillary posterior teeth may lead to insufficient bone in the posterior maxilla for endosseous dental implant placement. This is due in part to the pneumatization of the maxillary sinuses. Different strategies for bone augmentation in the posterior maxilla have been attempted including techniques involving alloplastic, allogenic, and autogenous bone grafts. The objective of this investigation was to evaluate the efficacy of autogenous bone harvested from the iliac crest for subantral augmentation of the maxillary sinus and subsequently the ability of this site development strategy to allow for osseointegration. Materials and Methods: Fifty-four patients (90 sinuses) with posterior maxillary alveolar ridge Lekholm-Zarb bone quality classification of 4 were evaluated. Bone was harvested from the anterior iliac crest in 17 patients and from the posterior iliac crests in 37. Forty-two patients were additionally treated with platelet rich plasma (PRP) at the time of bone graft placement. Two hundred seven root form endosseous dental implants were placed 6 to 9 months after initial graft surgery. Pantomography was used to evaluate posterior maxillary alveolar ridge height preoperatively (T1), immediately postoperatively (T2), and at the time of dental implant insertion (T3). Results: Alveolar height was seen to increase at T2 by 14 mm with subsequent bone height loss at T3 during graft consolidation prior to implant insertion of 1.2 mm. The overall rate of osseointegration of the endosseous implants was found to be 94.7%. Eighteen patients experienced postoperative complications including soft tissue infection of the grafted site, implant failure, dehiscence of the grafted site, soft tissue infection of the donor site, sinus infection with fistulae, and seroma of the posterior hip donor site. Nine patients treated with PRP had bone cores harvested at the time of implant insertion and histomorphometric analysis revealed an average of 46.4% vital bone per core. No statistically significant differences in implant success were found with respect to gender, application of PRP, the different implant systems used, or donor site used. Conclusion: The 2 step approach to posterior maxillary reconstruction with bone graft harvest from the iliac 90
crest followed by dental implant placement at 6 to 9 months allows for predictable maxillary reconstruction and osseointegration. References Pejrone G, Lorenzetti M, Mozzati M, et al: Sinus floor augmentation with autogenous iliac bone block grafts: A histological and histomorphometrical report on the two-step surgical technique. Int J Oral Maxillofac Surg 13:69, 1998 Lekholm U, Wannfors K, Isaksson S, et al: Oral implants in combination with bone grafts: A 3-year retrospective multicenter system. Int J Oral Maxillofac Surg 28:187, 1999
POSTER 18 Maxillary Distraction by Intraoral Devices Patricia Lopez, DDS, Santa Rosa Maxillofacial Surgery Center, Centro Integral Santa Rosa, #105, Caracas, 1061 Venezuela (Figueroa F; Dominguez E; Guerrero CA) Purpose: Evaluate an intraoral device to bi- or 3-dimensionally reposition the maxilla by distraction osteogenesis, avoiding the use of bone grafts or heavy rigid fixation. Facial deformities were treated at different levels: Le Fort I, high Le Fort I, and modified Le Fort III were included in this study. Materials and Methods: Thirty-six patients (12 to 35 years old, average 18.4) were treated by maxillary advancement at different osteotomy levels. All the patients underwent a combined surgical-orthodontics treatment, and transverse, vertical, and anteroposterior movements were carefully evaluated. An intraoral dynaform appliance was utilized on either side, anchoraged to the zygomatic bone or to the pyramidal apophysis. The protocol used was: 7 days latency, 1 mm per day activation, and 90 days consolidation period. The minimal age to indicate the surgery was based on enough surgical space between the root of the canine (5 mm above the apex), the infraorbital nerve, and the lacrimal duct. Complete radiographs and photographs were obtained pre- and immediately postsurgery, 3 months after, at the appliance removal stage, and 6 months after braces were removed. Dental models in an articulator were taken before the surgery and after braces removal. Results: The maxilla was advanced 8 to 14 mm (average, 10.5), the canines were evaluated by pulp test with positive response at the braces removal stage, no teeth were damaged, and no epiphora or infraorbital nerve dysesthesia occurred. The dental occlusions were Class I with adequate overbite and overjet, with noncanted occlusal planes. Conclusions: The intraoral devices are ideal means to advance the maxilla in a bi-dimensional manner and may also be combined with maxillary widening in particular situations. This surgical approach eliminates the need for AAOMS • 2003