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The PTFE wound dressing in alveolar bone grafting
Abstracts not hard tissue replacement promotes healing and reduces the risk of osteoradionecrosis, the material was used in eight patients with 45 extraction sites. The radiation doses ranged from 4000 cGy to 7440 cGy. The times of extractions after radiation ranged from 2 to 11 years. The grafting material consists of porous polymethylmethacrylate spheres coated with polyhydroxyethylmethacrylate and calcium hydroxide. Before placement of HTR. blood from the extraction site(s) was aspirated into the syringe containing it and tetracycline powder was added. The material was then compacted with a blunt instrument into the socket(s), the soft tissue was sutured over the site(s). The patients were examined at I-2-week intervals postoperatively. Epithelization occurred in all within 2-3 weeks. Clinically and radiographically, no infection, exfoliation of bone or suppuration characteristic of osteoradionecrosis developed. HTR appears to act as scaffolding for bone and soft tissue neoformation and offers a practical and easily applied approach to extractions without hyperbaric oxygen treatment in irradiated patients.
TMD: clinical and laboratory analyses to develop risk assessment criteria for surgical/non-surgical therapy. D. C. C/zuse DOS, L. R. Hdprrn DDS, MD, D. A. Gerard PhD. M. M. B&T DDS. University of Tennessee Graduate School of Medicine. Knoxville. Tennessee, USA. Presented by: Leslie R. Halpern DDS. MD, TMD describes not only TMJ dysfunction but disease of related musculoskeletal structures, affecting up to 40% of the population with a preponderance of females (10: 1 male). We describe a study of 55 patients with failed surgical manipulation to relieve the TMD. All patients had previous non-surgical therapy. The patients were separated into 6 groups and 1 control group. Group ( I ) early ID; (2) arthrotomy/meniscectomy; ( 3) failed IVSCOs; (4) Christensen glenoid fossa; (5) Christensen total joint; (6) Eagle’s syndrome. The control group consisted of asymptomatic patients both clinically and radiographically. Lab tests included HLA-A,B,DRW.RF. ANA sub-types, ESR. anemia profile, acute-phase reactants. uric acid and hormonal levels of Prolactin, estradiol and TFTs. Medical histories of groups 3-6 elicited significant inflammatory bowel disease, headaches, vertigo. tinnitus and anemia. Surgical histories included tonsillectomies. appendectomies and choleystectomies. Controls were negative for their past medical and surgical histories. HLA frequencies of groups 4-6 were significant for HLA-A2,A3,A26,HLA-B-B7,BS,B17.B44,B44,B6O,B62. Fifty percent of the groups 2 6 were positive for RF, ANA subtypes, increased ESR and anemia. The control group was negative for each lab examined at the same sex and age. There was no significant diffkrences in hormonal levels between control and experimental groups of the same sex and age. These findings suggest that, in the experimental groups, surgical failure may be secondary to autoimmunc dysfunction with a predisposition to multisystem disease. The utilization of genetic markers, serological testing and thorough medical histories should allow the clinician to determine which patients are good surgical risks. Furthermore. the markers in our study will enable the clinician to monitor the progression of disease to determine alternative treatment modalities.
Outpatient maxillofacial surgery: the transition 200 cases. J. J. Dunn MD, DMD. PTl~.WltPd hy: J. J. Dam MD, DMD.
and outcomes
after
Short-acting anesthetic agents, deliberate hypertension. decreased operating times, rigid fixation and non-narcotic analgesics have combined to yield a remarkable decrease in the perioperative morbidity associated with maxillofacial surgical procedures and a more rapid predictable recovery from surgery. This has allowed a transition of procedures traditionally performed in an inpatient setting to an outpatient setting. The transition of major maxillofacial surgery to an outpatient setting involved adoption of protocols dealing with: case and patient selection criteria; anesthetic management; criteria for discharge disposition; staff training. The process of developing and adopting those protocols is discussed. Treatment outcomes for the first 200 cases are discussed. Case types, OR times and blood loss are presented. No cases required transfusion. A subsequent
admission underwent
from
the ACOMS
18th Annual
rate of 1% was experienced. unplanned revision.
Less
Conference than
The tongue flap in alveolar bone grafting. R. H. Eilhros DMD, MD, C. Hull MD. Veteran’s Medical Center. East Orange. New Jersey. USA. Presented by: Robert DeFalco DDS.
443
I’:/;) of cases
DeFuko DDS. Administration
A posteriorly based tongue flap has been utilized to provide oral soft tissue coverage over an alveolar bone graft. It is presented as a method of managing the challenging defect seen in patients with bilateral cleft lip and palate whose premaxillary segment has been removed. Such defects may occur where access to a sophisticated level of primary cleft care is limited. Standard techniques for accomplishing a tension-free closure over the grafted material ma> not be applicable in these cases. The treatment of one such patient is described. The nasal floor was reconstructed in a typical fashion using locally elevated soft tissue flaps. The defect was measured and a posteriorly based tongue flap of appropriate size was developed. The flap was sutured to the posterior and lateral wound margins, leaving an anterior tunnel for placement of autogenous bone from the iliac crest. After placement of the graft and closure of the anterior margin. a wedge of tissue was excised to allow for esthetic reconstruction of the anterior tongue. Upon release of the flap 20 days later, good soft tissue coverage of the grafted defect was noted and function and esthetics were quite satisfactory. This technique, which has been reported for a variety of other applications. appears well suited for use in patients as described above.
Tetracycline in the surgical management of osteomyelitis. R. DrFtrlw DDS, H. Ephrus DMD, MD. L. Signum DDS. Seton Hall University School of Graduate Medical Education, South Orange. New Jersey, USA. Presented by: Robert De Falco DDS. Tetracycline is used as a marker to identify the borders of vital bone in patients with osteomyelitis who reqiire surgical treatment. The techniaue described below allows for a guided debridement which may be more thorough yet more conser;ative. Patients with osteomyelitis of the mandible are treated with tetracycline 250 mg b.i.d. for three to five days prior to surgical debridement. This is in addition to and does not replace the indicated antibiotic therapy for these patients. Intraoperatively, the area is approached using standard techniques exposing several centimeters of bone on either side of the involved area. Operating room lights are turned off and an ultraviolet light source is used to illuminate the operative site. Vital bone fluoresces brightly, while nonvital bone simply reflects the light source. The dull glow of the nonvital area is clearly distinguishable from the brilliant fluorescence seen where boric is vital. We believe that the intraoperative guidance provided by this technique has resulted in definitive debridements with maximal preservation of uninvolved tissue. The technique appears to be a useful tool in the management of osteomyelitis. particularly in the most Dersistent and difficult case,.
The PTFE wound dressing in alveolar hone grafting. H. Ephros DMD, MD. R. DeFdco DDS. C’. HuII MD. Seton Hall University School of Graduate Medical Education. South Orange, New Jersey. USA. Presented by: Robert DeFalco DDS. A polytetrafluoroethylene (PTFE) wound-dressing technique has been utilized to protect the oral closure after alveolar bone grafting. It is presented as a method that may reduce the incidence of dehiscence and graft loss. Failure to produce and maintain an adequate bony bridge in the grafted site occurs in a small percentage of cases and may be attributable. at least in part. to early dehiscence of the overlying soft tissue. This complication can be initiated and!or aggravated by exploration of the surgical site by the patient’s tongue, a behavior noted even in compliant children. The use of a 0.4 mm PTFE cardiovascular patch to cover the intraoral surgical site may result in fewer dehiscences. The patch is cut and shaped to cover the oral closure, is retained by silk sutures. and is generally left in place for ten days. No statistically significant data
444
British
Journal
of Oral
and Maxillofacial
Surgery
are available to validate the superiority of this technique over simply leaving the oral line of closure uncovered. However, the anecdotal information generated by the use of this technique on twelve recently grafted UCLP and BCLP patients may be significant. The exposed surface of the membrane becomes coated with debris during the first postoperative week. Upon removal of the membrane, the oral mucosa overlying the graft is remarkably clean and the closure is consistently intact.
A two year follow-up study on bioceramic glass implants placed in the medically immunocompromised patient. Steven Garin DMD, John Coyne DMD, Allen Fred Fieldin DMD, David Kind DMD,
Temple University Hospital, Philadelphia, Pennsylvania, USA. Presented by: Steven Garin DMD. Bioactive endosseous ridge maintenance implants are hard nonporous surface reactive cones that press fit into mechanically prepared fresh extraction sites to maintain dentoalveolar ridge contour. Traditionally, these implants have been placed in ASA I healthy individuals. However, it is usually the medically immunocompromised patient that undergoes the most dentoalveolar ridge resorption and thus requires the best possible ridge preservation. Also, it is the medically immunocompromised patient, who is not traditionally a candidate for this type of oral and maxillofacial surgical procedures, who benefits most from this simple office procedure. After insertion of the implant, a calcium-silica-rich gel is formed on the implant surface and calcium-phosphate from the tissue fluid precipitates onto this layer. Later, osteoblasts proliferate on this interface and anchor collagen fibers into the implant which then begins to elaborate bone upon the implant surface. Our study involved the placement of over 200 bioactive ceramic endosseous implants that were placed in 20 medically immunocompromised patients. The implants were press fitted into mechanically prepared fresh extraction sites and submerged up to 2-3 mm below the dentoalveolar bone. During extraction of the teeth, there were cases of buccal cortex fracture resulting in exposure of 0.5-l mm of the implant upon placement. All the surgical sites were primarily closed and loading delayed for at least 12 weeks postoperatively. Earlier studies have shown retention rates of over 90% in non-medically compromised patients. We previously reported preliminary data over a 6-month period showing a retention rate of over 90%. Our follow-up clinical data show a continued retention rate of implants placed in the medically immunocompromised patient with preservation of dentoalveolar ridge contour comparable to that of the non-medically compromised patients with this type of implant. Of interest, our follow-up study showed formation of host bone over the previously exposed buccal portion of the implants.
A comparison of the effects of tobacco smoke and transdermal nicotine on alveolar bone growth and tooth development in the rat. Alan S. Herford DOS, Philip J. Boyne DMD, Southwestern Medical
Center, University of Texas, Dallas, Texas, USA. Presented by: Alan S. Herford DDS. Objective: Seventy-five Fischer 344 rats were studied to compare the effects of tobacco smoke and transdermal nicotine (TN) on alveolar bone growth and tooth development. Procedure: The animals were randomly divided into five groups consisting of two control groups, one smoking group, one TN group, and one group which received both smoking and TN protocol. Animals in the tobacco inhalation groups were exposed to a standard reference cigarette which contained 2.45 mg nicotine per cigarette at a dose of three cigarettes per day (15-human p&k vears). The rats in the TN grouus had their backs shaved and a i-cmi patch containing 1.Omg ofnicotine was applied. All animals were given tetracycline to label osseous matrix formation at the onset and cessation of their smoke and/or TN exposure. Results: Histomorphometric analysis was used to evaluate the amount of bone matrix formed. The inferior border of the mandible and the lower incisor were chosen as the areas to be evaluated because of the anatomy and presence of prominent growth potential. ANOVA was utilized to compare smoking or TN groups with controls, and individual groups were analyzed by a paired t-test.
Study animals who were exposed to smoke had less bone formation than the control animals. The rats receiving the l.O-mg nicotine patch had less bone growth than the controls or the smoking groups. Conclusions: The practice, in some areas, of recommending that smoking patients use the transdermal patch post-surgically to establish improvement in soft tissue and bone healing, may be creating a potentially unfavorable bone healing environment.
The use of stereolithographic laser models in OMFS. Craig Jonov DMD, MD, Steven I. Kaltman DMD, Allegheny General Hospital,
Pittsburgh, Pennsylvania, USA. Presented by: Steven I. Kaltman DMD. Stereolithography is a laser-aided technique for the production of three-dimensional plastic components without using any tools, dyes, or other materials. With the help of this technology, it is possible to produce models and prototypes of utmost complexity and precision from geometric computer data generated by threedimensional computer-assisted design systems in a timely manner. A computer-guided laser beam draws individual cross-sections of a model into layers of a photosensitive liquid synthetic material, Stereolithographic laser-formed and fused deposition threedimensional models of bony structures are now available for planning and performing oral and maxillofacial surgical procedures on the facial skeleton. These precise models allow surgeons to study the bony structures of a patient’s face separately from the body and to manipulate their shapes as necessary to achieve the desired result. Models also permit a measurement of structures, the testing of osteotomies and resection techniques, and complete planning for almost all types of oral and maxillofacial surgery. In addition to applications in pre-prosthetic and tumor surgery, threedimensional modeling can assist in surgical correction of malocclusions and congenital deformities, as well as facilitate acute and delayed trauma repair and reconstruction. Planning surgical procedures with the help of a model creates the advantage of simulating surgical conditions in an environment that closely reproduces the actual conditions. Surgical strategy can be developed based on a clear view of the surgical site. With so much emphasis on providing quality care at lower cost in today’s managed-care environment, models reduce the time needed to complete the actual procedure, decrease anesthesia time, and lower the patient’s risk of infection. The enormous potential and advantages of modeling technology justify the current labor requirements and cost of fabricating these models.
Rehabilitation rated implants. DDS, Tufts
of patients with reconstructed Maria B. Papageorge, DMD,
University School of Dental Massachusetts, USA. Presented by: Stella Karabetou DDS.
jaws using osseointegMS, Stella Karabetou,
Medicine,
Boston,
Surgical therapy in patients with benign or malignant neoplasm often results in problems with cosmetic deformity, speech and masticatory function. Through maxillary and mandibular reconstruction, we can re-establish anatomical ‘form’ and oral ‘function’. However, some of these patients are unable to wear conventional removable prostheses. In these cases, prosthetic dental rehabilitation can be achieved through implant or tissue supported prostheses. We are reporting our experience with 11 patients who underwent maxillary or mandibular surgical reconstruction with iliac crest autogenous bone graft and placement of titanium screw type implants (Branemark). The implants were exposed after six months and all patients have been reconstructed prosthetically. We review the types of surgical reconstruction, pre-surgical prosthetic planning, restorative prosthetic reconstruction phases of treatment, and the problems and solutions encountered during treatment. Placement of implants in these reconstructed jaws provides a challenge. However, analysis of these cases reveals that grafted bone can be an excellent host for osseointegrated implants. It can act as a sole support of the implants and the prosthesis or the adjacent bone can also be used to place the implants to aid in support of the prosthesis.
TMD: clinical and laboratory analyses to develop risk assessment criteria for surgical/non-surgical therapy. D. C. C/zuse DOS, L. R. Hdprrn DDS, MD, D. A. Gerard PhD. M. M. B&T DDS. University of Tennessee Graduate School of Medicine. Knoxville. Tennessee, USA. Presented by: Leslie R. Halpern DDS. MD, TMD describes not only TMJ dysfunction but disease of related musculoskeletal structures, affecting up to 40% of the population with a preponderance of females (10: 1 male). We describe a study of 55 patients with failed surgical manipulation to relieve the TMD. All patients had previous non-surgical therapy. The patients were separated into 6 groups and 1 control group. Group ( I ) early ID; (2) arthrotomy/meniscectomy; ( 3) failed IVSCOs; (4) Christensen glenoid fossa; (5) Christensen total joint; (6) Eagle’s syndrome. The control group consisted of asymptomatic patients both clinically and radiographically. Lab tests included HLA-A,B,DRW.RF. ANA sub-types, ESR. anemia profile, acute-phase reactants. uric acid and hormonal levels of Prolactin, estradiol and TFTs. Medical histories of groups 3-6 elicited significant inflammatory bowel disease, headaches, vertigo. tinnitus and anemia. Surgical histories included tonsillectomies. appendectomies and choleystectomies. Controls were negative for their past medical and surgical histories. HLA frequencies of groups 4-6 were significant for HLA-A2,A3,A26,HLA-B-B7,BS,B17.B44,B44,B6O,B62. Fifty percent of the groups 2 6 were positive for RF, ANA subtypes, increased ESR and anemia. The control group was negative for each lab examined at the same sex and age. There was no significant diffkrences in hormonal levels between control and experimental groups of the same sex and age. These findings suggest that, in the experimental groups, surgical failure may be secondary to autoimmunc dysfunction with a predisposition to multisystem disease. The utilization of genetic markers, serological testing and thorough medical histories should allow the clinician to determine which patients are good surgical risks. Furthermore. the markers in our study will enable the clinician to monitor the progression of disease to determine alternative treatment modalities.
Outpatient maxillofacial surgery: the transition 200 cases. J. J. Dunn MD, DMD. PTl~.WltPd hy: J. J. Dam MD, DMD.
and outcomes
after
Short-acting anesthetic agents, deliberate hypertension. decreased operating times, rigid fixation and non-narcotic analgesics have combined to yield a remarkable decrease in the perioperative morbidity associated with maxillofacial surgical procedures and a more rapid predictable recovery from surgery. This has allowed a transition of procedures traditionally performed in an inpatient setting to an outpatient setting. The transition of major maxillofacial surgery to an outpatient setting involved adoption of protocols dealing with: case and patient selection criteria; anesthetic management; criteria for discharge disposition; staff training. The process of developing and adopting those protocols is discussed. Treatment outcomes for the first 200 cases are discussed. Case types, OR times and blood loss are presented. No cases required transfusion. A subsequent
admission underwent
from
the ACOMS
18th Annual
rate of 1% was experienced. unplanned revision.
Less
Conference than
The tongue flap in alveolar bone grafting. R. H. Eilhros DMD, MD, C. Hull MD. Veteran’s Medical Center. East Orange. New Jersey. USA. Presented by: Robert DeFalco DDS.
443
I’:/;) of cases
DeFuko DDS. Administration
A posteriorly based tongue flap has been utilized to provide oral soft tissue coverage over an alveolar bone graft. It is presented as a method of managing the challenging defect seen in patients with bilateral cleft lip and palate whose premaxillary segment has been removed. Such defects may occur where access to a sophisticated level of primary cleft care is limited. Standard techniques for accomplishing a tension-free closure over the grafted material ma> not be applicable in these cases. The treatment of one such patient is described. The nasal floor was reconstructed in a typical fashion using locally elevated soft tissue flaps. The defect was measured and a posteriorly based tongue flap of appropriate size was developed. The flap was sutured to the posterior and lateral wound margins, leaving an anterior tunnel for placement of autogenous bone from the iliac crest. After placement of the graft and closure of the anterior margin. a wedge of tissue was excised to allow for esthetic reconstruction of the anterior tongue. Upon release of the flap 20 days later, good soft tissue coverage of the grafted defect was noted and function and esthetics were quite satisfactory. This technique, which has been reported for a variety of other applications. appears well suited for use in patients as described above.
Tetracycline in the surgical management of osteomyelitis. R. DrFtrlw DDS, H. Ephrus DMD, MD. L. Signum DDS. Seton Hall University School of Graduate Medical Education, South Orange. New Jersey, USA. Presented by: Robert De Falco DDS. Tetracycline is used as a marker to identify the borders of vital bone in patients with osteomyelitis who reqiire surgical treatment. The techniaue described below allows for a guided debridement which may be more thorough yet more conser;ative. Patients with osteomyelitis of the mandible are treated with tetracycline 250 mg b.i.d. for three to five days prior to surgical debridement. This is in addition to and does not replace the indicated antibiotic therapy for these patients. Intraoperatively, the area is approached using standard techniques exposing several centimeters of bone on either side of the involved area. Operating room lights are turned off and an ultraviolet light source is used to illuminate the operative site. Vital bone fluoresces brightly, while nonvital bone simply reflects the light source. The dull glow of the nonvital area is clearly distinguishable from the brilliant fluorescence seen where boric is vital. We believe that the intraoperative guidance provided by this technique has resulted in definitive debridements with maximal preservation of uninvolved tissue. The technique appears to be a useful tool in the management of osteomyelitis. particularly in the most Dersistent and difficult case,.
The PTFE wound dressing in alveolar hone grafting. H. Ephros DMD, MD. R. DeFdco DDS. C’. HuII MD. Seton Hall University School of Graduate Medical Education. South Orange, New Jersey. USA. Presented by: Robert DeFalco DDS. A polytetrafluoroethylene (PTFE) wound-dressing technique has been utilized to protect the oral closure after alveolar bone grafting. It is presented as a method that may reduce the incidence of dehiscence and graft loss. Failure to produce and maintain an adequate bony bridge in the grafted site occurs in a small percentage of cases and may be attributable. at least in part. to early dehiscence of the overlying soft tissue. This complication can be initiated and!or aggravated by exploration of the surgical site by the patient’s tongue, a behavior noted even in compliant children. The use of a 0.4 mm PTFE cardiovascular patch to cover the intraoral surgical site may result in fewer dehiscences. The patch is cut and shaped to cover the oral closure, is retained by silk sutures. and is generally left in place for ten days. No statistically significant data
444
British
Journal
of Oral
and Maxillofacial
Surgery
are available to validate the superiority of this technique over simply leaving the oral line of closure uncovered. However, the anecdotal information generated by the use of this technique on twelve recently grafted UCLP and BCLP patients may be significant. The exposed surface of the membrane becomes coated with debris during the first postoperative week. Upon removal of the membrane, the oral mucosa overlying the graft is remarkably clean and the closure is consistently intact.
A two year follow-up study on bioceramic glass implants placed in the medically immunocompromised patient. Steven Garin DMD, John Coyne DMD, Allen Fred Fieldin DMD, David Kind DMD,
Temple University Hospital, Philadelphia, Pennsylvania, USA. Presented by: Steven Garin DMD. Bioactive endosseous ridge maintenance implants are hard nonporous surface reactive cones that press fit into mechanically prepared fresh extraction sites to maintain dentoalveolar ridge contour. Traditionally, these implants have been placed in ASA I healthy individuals. However, it is usually the medically immunocompromised patient that undergoes the most dentoalveolar ridge resorption and thus requires the best possible ridge preservation. Also, it is the medically immunocompromised patient, who is not traditionally a candidate for this type of oral and maxillofacial surgical procedures, who benefits most from this simple office procedure. After insertion of the implant, a calcium-silica-rich gel is formed on the implant surface and calcium-phosphate from the tissue fluid precipitates onto this layer. Later, osteoblasts proliferate on this interface and anchor collagen fibers into the implant which then begins to elaborate bone upon the implant surface. Our study involved the placement of over 200 bioactive ceramic endosseous implants that were placed in 20 medically immunocompromised patients. The implants were press fitted into mechanically prepared fresh extraction sites and submerged up to 2-3 mm below the dentoalveolar bone. During extraction of the teeth, there were cases of buccal cortex fracture resulting in exposure of 0.5-l mm of the implant upon placement. All the surgical sites were primarily closed and loading delayed for at least 12 weeks postoperatively. Earlier studies have shown retention rates of over 90% in non-medically compromised patients. We previously reported preliminary data over a 6-month period showing a retention rate of over 90%. Our follow-up clinical data show a continued retention rate of implants placed in the medically immunocompromised patient with preservation of dentoalveolar ridge contour comparable to that of the non-medically compromised patients with this type of implant. Of interest, our follow-up study showed formation of host bone over the previously exposed buccal portion of the implants.
A comparison of the effects of tobacco smoke and transdermal nicotine on alveolar bone growth and tooth development in the rat. Alan S. Herford DOS, Philip J. Boyne DMD, Southwestern Medical
Center, University of Texas, Dallas, Texas, USA. Presented by: Alan S. Herford DDS. Objective: Seventy-five Fischer 344 rats were studied to compare the effects of tobacco smoke and transdermal nicotine (TN) on alveolar bone growth and tooth development. Procedure: The animals were randomly divided into five groups consisting of two control groups, one smoking group, one TN group, and one group which received both smoking and TN protocol. Animals in the tobacco inhalation groups were exposed to a standard reference cigarette which contained 2.45 mg nicotine per cigarette at a dose of three cigarettes per day (15-human p&k vears). The rats in the TN grouus had their backs shaved and a i-cmi patch containing 1.Omg ofnicotine was applied. All animals were given tetracycline to label osseous matrix formation at the onset and cessation of their smoke and/or TN exposure. Results: Histomorphometric analysis was used to evaluate the amount of bone matrix formed. The inferior border of the mandible and the lower incisor were chosen as the areas to be evaluated because of the anatomy and presence of prominent growth potential. ANOVA was utilized to compare smoking or TN groups with controls, and individual groups were analyzed by a paired t-test.
Study animals who were exposed to smoke had less bone formation than the control animals. The rats receiving the l.O-mg nicotine patch had less bone growth than the controls or the smoking groups. Conclusions: The practice, in some areas, of recommending that smoking patients use the transdermal patch post-surgically to establish improvement in soft tissue and bone healing, may be creating a potentially unfavorable bone healing environment.
The use of stereolithographic laser models in OMFS. Craig Jonov DMD, MD, Steven I. Kaltman DMD, Allegheny General Hospital,
Pittsburgh, Pennsylvania, USA. Presented by: Steven I. Kaltman DMD. Stereolithography is a laser-aided technique for the production of three-dimensional plastic components without using any tools, dyes, or other materials. With the help of this technology, it is possible to produce models and prototypes of utmost complexity and precision from geometric computer data generated by threedimensional computer-assisted design systems in a timely manner. A computer-guided laser beam draws individual cross-sections of a model into layers of a photosensitive liquid synthetic material, Stereolithographic laser-formed and fused deposition threedimensional models of bony structures are now available for planning and performing oral and maxillofacial surgical procedures on the facial skeleton. These precise models allow surgeons to study the bony structures of a patient’s face separately from the body and to manipulate their shapes as necessary to achieve the desired result. Models also permit a measurement of structures, the testing of osteotomies and resection techniques, and complete planning for almost all types of oral and maxillofacial surgery. In addition to applications in pre-prosthetic and tumor surgery, threedimensional modeling can assist in surgical correction of malocclusions and congenital deformities, as well as facilitate acute and delayed trauma repair and reconstruction. Planning surgical procedures with the help of a model creates the advantage of simulating surgical conditions in an environment that closely reproduces the actual conditions. Surgical strategy can be developed based on a clear view of the surgical site. With so much emphasis on providing quality care at lower cost in today’s managed-care environment, models reduce the time needed to complete the actual procedure, decrease anesthesia time, and lower the patient’s risk of infection. The enormous potential and advantages of modeling technology justify the current labor requirements and cost of fabricating these models.
Rehabilitation rated implants. DDS, Tufts
of patients with reconstructed Maria B. Papageorge, DMD,
University School of Dental Massachusetts, USA. Presented by: Stella Karabetou DDS.
jaws using osseointegMS, Stella Karabetou,
Medicine,
Boston,
Surgical therapy in patients with benign or malignant neoplasm often results in problems with cosmetic deformity, speech and masticatory function. Through maxillary and mandibular reconstruction, we can re-establish anatomical ‘form’ and oral ‘function’. However, some of these patients are unable to wear conventional removable prostheses. In these cases, prosthetic dental rehabilitation can be achieved through implant or tissue supported prostheses. We are reporting our experience with 11 patients who underwent maxillary or mandibular surgical reconstruction with iliac crest autogenous bone graft and placement of titanium screw type implants (Branemark). The implants were exposed after six months and all patients have been reconstructed prosthetically. We review the types of surgical reconstruction, pre-surgical prosthetic planning, restorative prosthetic reconstruction phases of treatment, and the problems and solutions encountered during treatment. Placement of implants in these reconstructed jaws provides a challenge. However, analysis of these cases reveals that grafted bone can be an excellent host for osseointegrated implants. It can act as a sole support of the implants and the prosthesis or the adjacent bone can also be used to place the implants to aid in support of the prosthesis.