- Email: [email protected]
O.116 Orthognatic surgery and microvascular reconstruction of maxillo-mandibular defects
32
Journal of Cranio-Maxillofacial Surgery 34(2006) Suppl. S1
bone movement are providing the basic data for investigations concerning the ratio between skeletal and facial soft tissue displacements. In the future matching the 3-D-scans with threedimensional reconstructed CT-data there is a big chance for planning orthognathic surgery. The bone movements of a virtual model surgery could transmitted to the soft tissue displacements. With this procedure the new facial appearance could get predictable three-dimensionally. O.112 The Simplant CMF software: A new way of planning in orthognathic surgery C. Marchetti, L. Bassani, S. Mazzoni, E. Ozeri. Oral and Maxillofacial Surgery Unit, S. Orsola Hospital, Bologna, Italy Objective: The aim of this study is to present a virtual-reality software for surgeons to perform virtual orthognathic surgical planning with 3D hard- and soft-tissue prediction. The study evaluates the role of a new computer imaging software (Simplant CMF software – Materialise) to plan the outcome of soft tissues after bimaxillary orthognathic surgery. Materials and Methods: The study sample consisted of 6 adults pts who had undergone orthognathic surgery that included Le Fort I and Bilateral Sagittal Split Osteotomy procedures and optional genioplasty to correct malformations. All the patients had cephalometric radiographs and CT scan. The surgical planning system consists of four stages: computed tomography data reconstruction, three-dimensional facial hard- and soft-tissue model generation, different virtual surgical plannings and simulations, pre-operative predictions of soft-tissue changements. The surgical planning and simulation are based on a 3D CT reconstructed bone model; the soft-tissue prediction is based on physical algorithm. Results: The software rapidly generates many simulations and soft tissue predictions according the clinical options; so it is possible to plan the surgery choosing between different aesthetic results. Pre-operative plannings were prepared working with the orthodontist to avoid functional problems. Conclusions: Simplant software is able to provide a prediction of post-operative appearance with realistic quality. The simulation can be visualized from any viewing point using a personalcomputer-based system, so this solution can be adopted for hospital daily use. The accuracy of the software in soft tissue will be discussed. O.113 Comparison of biomechanical stability of 2.0 mm standard and 2.0 mm locking screws for SSRO Y. Oguz1 , S. Uckan1 , D. Dolanmaz2 . 1 Department of Oral and Maxillofacial Surgery, Baskent University School of Dentistry, Turkey; 2 Department of Oral and Maxillofacial Surgery, Selcuk University School of Dentistry, Turkey Introduction and Objectives: Several techniques have been used for the rigid fixation of the mandible after sagittal split ramus osteotomies (SSRO). Although standard miniplates and screws are very well known and widely used technique locking plate and screw systems are available for over 15 years in oral and maxillofacial surgery. The aim of the present study was to compare the stability of the SSROs that will be fixed with 2.0 standard miniplates and screws or 2.0 locking plates and screws in sheep mandibles. Material and Methods: Ten unembalmed fresh mandibles from adult sheep were stripped of all soft tissues and sectioned in the midline. SSROs were then carried out by using fissure burs and reciprocal saws. After that the osteotomy 5 mm advancement
Abstracts, EACFMS XVIII Congress were performed on each of the 20 hemimandibles. The 2.0 locking plate and screw system (4-hole plate with space and 6 mm locking screws) were applied to 10 of the hemimandibles and a titanium 4-hole miniplate and 2.0 monocortical 6 mm length screws were used for fixation of the SSRO. All of the hemimandibles were mounted in the special test fixture and 0– 140 N forces were applied to all specimens. Displacement of each proximal segment was recorded at 10 N increments from 0 to 140 N. Values for the two groups were compared using the Mann–Whitney U -test. Results: There was no significant difference between the groups (p > 0.05). Conclusions: Plates with locked screws provided similar stability with standard miniplate in sheep mandibles after SSRO. O.114 Post-operative stability following orthognathic surgery in patients with pre-operative condylar resorption S.J. Hwang, S.-Y. Lee, D.K. Kim. Department of Oral and Maxillofacial Surgery, College of Dentistry, Seoul National University, South Korea Objectives: Condylar resorption can occur spontaneously or after orthognathic surgery. Post-operative condylar resorption is an important cause of late skeletal relapse, and pre-operative condylar resorption can go on after orthognathic surgery. The purpose of this study is to evaluate the stability of orthognathic surgery in patients with preoperative condylar resorption, which has been never reported in the literature. Patients and Methods: Fifteen patients (Group I) with pre-operative condylar resorption who underwent orthognathic surgery were selected in this retrospective study. These patients were analysed with radiological data (cephalogram and orthopantomogram) collected pre-operatively and immediately, 6 weeks, and 1 year post-operatively. Results: All patients were young females (<25 years old), they showed skeletal class II malocclusion with high mandibular plane angle and posteriorly inclined condylar neck. Le Fort I osteotomy and bilateral sagittal split osteotomy were performed by one surgeon in all patients, which were stabilized with rigid fixation using miniplate. There was no apparent post-operative condylar resorption in all orthopantomograms 1 year post-operatively. Cephalometrical analysis showed stable post-operative results. Cephalometrical changes (SNB, mandibular plane angle, overbite and overjet) between immediate, 6 weeks and 1 year post-operatively were statistically not significant (p > 0.05). The amount of anterior–posterior mandibular relapse less than 1 mm 1 year post-operatively compared with immediate post-operatively. Conclusion: The present study suggests that orthognathic surgery can be performed safely in the patients with preoperative condylar resorption. A further study with long-term follow up more than 1 year is necessary. O.116 Orthognatic surgery and microvascular reconstruction of maxillo-mandibular defects P. Gennaro1 , C. Carnevale1 , I. Aboh1 , V. Valentini2 . 1 Universit`a di Roma “La Sapienza” Maxillofacial Department, 2 Oral Surgery and Maxillofacial Department, Universit`a di Roma “Tor Vergata”, Italy Introduction: The refinement of microsurgical reconstructive techniques has improved the possibilities for the treatment of complex maxillo-mandibular defects. In these cases, as in those of major resections or youthful traumas as well as the cases of post-radiation scars, orthognatic surgery is a valid complement
Oral Presentations
Bisphosphonate related diseases
to microvascular reconstruction. This combination allows for a better aesthetic and functional result. Materials and Methods: Seven cases of patients afflicted with both grave bone defects and malocclusions underwent microvascular reconstruction and orthognatic surgery. Three of these cases had suffered defects on account of mandibular resection and radiotherapy. Two were the result of hemimandibulectomy during their growing years; one case was the result of a hemimaxillectomy and RT. Results: In all the cases, the combined microvascular/orthognatic surgery allowed for an improved aesthetic and functional aspect. Discussion: The paper presents the seven cases fully and discusses the advantages of this combined surgery. Particular attention is given to the order of the combined surgery (whether the orthognatic precedes microvascular or vice versa). This ordering should depend on the needs of each patient.
Tuesday, 12 September 2006, 14.30−15.40
Hall 3
Bisphosphonate related diseases O.117 Osteonecrosis of the jaw(s) associated with the use of bisphosphonates: An iatrogenic epidemic J. Schoenaers, B. Moerenhout, F. Combes. Department of Oral Pathology and Oral & Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven, Belgium Iatrogenic disease in the oral cavity is ever increasing with the ageing of the population and the introduction of new treatment modalities. Biphophonates, used mainly in palliation for Kahler’s and metastatic disease to the bones, are associated with necrosis of the jaws (ONJ). Presently, bisphosphonates are widely used in the treatment of osteoporosis. They are known to be potent osteoclast inhibitors. ONJ is mainly reported when administering chronical IV highdose bisphosphonate therapy, often in combination with corticosteroids and cytostatics. We present a series of 38 patients with ONJ. The typical lesions vary from a non-healing mucosal wound to an exposed jawbone. Evaluation consisted in clinical, radiologic and radionucleide exams. Thirty-seven patients received high-dose intravenous therapy with either zolendronic acid or pamidronate or both. One patient received oral therapy with alendronate for the treatment for osteoporosis. In 27 patients the lower jaw, in 7 the upper jaw, and in 5 both jaws were affected. In 13 instances the epithelial defect had no traumatic antecedent. In 24 a tooth extraction and in 4 an irritation by a denture base was at the onset of ONJ. Oral hygiene, antiseptics antibiotics, and minimal debridement almost never achieved healing. The majority of these patients required surgical procedures to remove the involved bone, and the use of gap spanning reconstruction plates. In the upper jaws ONJ caused progressive loss of bone structures. Prevention of treatment refractory ONJ will be the challenge for the future.
33
O.118 Management of patients with bisphosphonatesinduced osteonecrosis R. Javadian, M. Shahla, E. Boutremans, I. Loeb. Department of Stomatology and Maxillofacial Surgery, CHU St-Pierre, Brussels, Belgium Introduction: Intravenous nitrogen containing bisphosphonates (BP) are widely used in the management of bone metastasis, hypercalcemia associated with malignancies and osteoporosis (long-term corticotherapy). Osteonecrosis-induced bisphosphonates is a dreadful side effect frequently apparent within a few months of use, with a mean occurrence in 6.7% of cases. However, this rate is rising rapidly in line with the increasing interest in BP mainly in major bone metastasis and the underlying inadequate oral and dental hygiene. Material and Methods: Within the past 6 months, a total number of 12 patients, 8 females and 4 males, were referred to our institution with necrotic lesions of the jaws together with suppuration, pain and exposed jawbone. Eleven patients had been receiving intravenous BP and, one oral BP chronically at admission between 12 and 120 months. Results: Nine (75%) patients presented a periodontal disorder. Seven patients had non-healing extraction socket. Three (25%) patients had spontaneous lesions and one presented a maladapted prosthesis. We observed a total of 16 necrosis sites in our series of which 10 (62.5%) were in the mandible and 6 (37.5%) in the maxilla. All patients benefited of a conservative therapy (CT). Surgical procedures were performed on the involved bone in 4 (33%) patients. Symptoms receded in 2 patients with gingival healing of the lesions only treated with CT. However this was not the case of patients requiring bone surgery. Conclusion: We therefore conclude that oro-dental preventive therapy in the treatment of BP osteonecrosis within our guidelines is a more viable and only alternative to surgical treatments. O.119 Six months follow-up results after therapy of osteonecrosis of the jaws under bisphosphonates A. Wutzl, C. Klug, G. Millesi-Schobel, A. Baumann. Department of Craniomaxillofacial and Oral Surgery, Medical University, Vienna, Austria Introduction and Objectives: Osteonecrosis of the jaws is described as an intraoral complication after administration of intravenously administered nitrogen containing bisphosphonates. At the moment there are about 300 published cases worldwide. However, clinical trials evaluating treatment strategies are still missing. Materials and Methods: We included in this study 20 patients with osteonecrosis of the jaws after bisphosphonate treatment, who were treated surgically in our department between July 2004 and June 2005. All patients had a malignant disease with osteolytic lesions. The median number of treatment cycles for pamidronate was 36 times. Zolendric acid was given 23.5 times. Six months post-operative patients were examined concerning wound healing, pain score, prosthetic rehabilitation and complications. For diagnostic evaluation a computertomography was done in all patients at the follow-up. Results: Seventeen patients were treated with sequestrectomy and decortication in general anaesthesia. In three patients minor surgical procedures were done. At the 6 month follow-up 10 patients showed intact oral mucosa, were free of pain and prosthetically rehabilitated. Ten patients had developed a recurrence of the mucosal lesion, suffered from
Journal of Cranio-Maxillofacial Surgery 34(2006) Suppl. S1
bone movement are providing the basic data for investigations concerning the ratio between skeletal and facial soft tissue displacements. In the future matching the 3-D-scans with threedimensional reconstructed CT-data there is a big chance for planning orthognathic surgery. The bone movements of a virtual model surgery could transmitted to the soft tissue displacements. With this procedure the new facial appearance could get predictable three-dimensionally. O.112 The Simplant CMF software: A new way of planning in orthognathic surgery C. Marchetti, L. Bassani, S. Mazzoni, E. Ozeri. Oral and Maxillofacial Surgery Unit, S. Orsola Hospital, Bologna, Italy Objective: The aim of this study is to present a virtual-reality software for surgeons to perform virtual orthognathic surgical planning with 3D hard- and soft-tissue prediction. The study evaluates the role of a new computer imaging software (Simplant CMF software – Materialise) to plan the outcome of soft tissues after bimaxillary orthognathic surgery. Materials and Methods: The study sample consisted of 6 adults pts who had undergone orthognathic surgery that included Le Fort I and Bilateral Sagittal Split Osteotomy procedures and optional genioplasty to correct malformations. All the patients had cephalometric radiographs and CT scan. The surgical planning system consists of four stages: computed tomography data reconstruction, three-dimensional facial hard- and soft-tissue model generation, different virtual surgical plannings and simulations, pre-operative predictions of soft-tissue changements. The surgical planning and simulation are based on a 3D CT reconstructed bone model; the soft-tissue prediction is based on physical algorithm. Results: The software rapidly generates many simulations and soft tissue predictions according the clinical options; so it is possible to plan the surgery choosing between different aesthetic results. Pre-operative plannings were prepared working with the orthodontist to avoid functional problems. Conclusions: Simplant software is able to provide a prediction of post-operative appearance with realistic quality. The simulation can be visualized from any viewing point using a personalcomputer-based system, so this solution can be adopted for hospital daily use. The accuracy of the software in soft tissue will be discussed. O.113 Comparison of biomechanical stability of 2.0 mm standard and 2.0 mm locking screws for SSRO Y. Oguz1 , S. Uckan1 , D. Dolanmaz2 . 1 Department of Oral and Maxillofacial Surgery, Baskent University School of Dentistry, Turkey; 2 Department of Oral and Maxillofacial Surgery, Selcuk University School of Dentistry, Turkey Introduction and Objectives: Several techniques have been used for the rigid fixation of the mandible after sagittal split ramus osteotomies (SSRO). Although standard miniplates and screws are very well known and widely used technique locking plate and screw systems are available for over 15 years in oral and maxillofacial surgery. The aim of the present study was to compare the stability of the SSROs that will be fixed with 2.0 standard miniplates and screws or 2.0 locking plates and screws in sheep mandibles. Material and Methods: Ten unembalmed fresh mandibles from adult sheep were stripped of all soft tissues and sectioned in the midline. SSROs were then carried out by using fissure burs and reciprocal saws. After that the osteotomy 5 mm advancement
Abstracts, EACFMS XVIII Congress were performed on each of the 20 hemimandibles. The 2.0 locking plate and screw system (4-hole plate with space and 6 mm locking screws) were applied to 10 of the hemimandibles and a titanium 4-hole miniplate and 2.0 monocortical 6 mm length screws were used for fixation of the SSRO. All of the hemimandibles were mounted in the special test fixture and 0– 140 N forces were applied to all specimens. Displacement of each proximal segment was recorded at 10 N increments from 0 to 140 N. Values for the two groups were compared using the Mann–Whitney U -test. Results: There was no significant difference between the groups (p > 0.05). Conclusions: Plates with locked screws provided similar stability with standard miniplate in sheep mandibles after SSRO. O.114 Post-operative stability following orthognathic surgery in patients with pre-operative condylar resorption S.J. Hwang, S.-Y. Lee, D.K. Kim. Department of Oral and Maxillofacial Surgery, College of Dentistry, Seoul National University, South Korea Objectives: Condylar resorption can occur spontaneously or after orthognathic surgery. Post-operative condylar resorption is an important cause of late skeletal relapse, and pre-operative condylar resorption can go on after orthognathic surgery. The purpose of this study is to evaluate the stability of orthognathic surgery in patients with preoperative condylar resorption, which has been never reported in the literature. Patients and Methods: Fifteen patients (Group I) with pre-operative condylar resorption who underwent orthognathic surgery were selected in this retrospective study. These patients were analysed with radiological data (cephalogram and orthopantomogram) collected pre-operatively and immediately, 6 weeks, and 1 year post-operatively. Results: All patients were young females (<25 years old), they showed skeletal class II malocclusion with high mandibular plane angle and posteriorly inclined condylar neck. Le Fort I osteotomy and bilateral sagittal split osteotomy were performed by one surgeon in all patients, which were stabilized with rigid fixation using miniplate. There was no apparent post-operative condylar resorption in all orthopantomograms 1 year post-operatively. Cephalometrical analysis showed stable post-operative results. Cephalometrical changes (SNB, mandibular plane angle, overbite and overjet) between immediate, 6 weeks and 1 year post-operatively were statistically not significant (p > 0.05). The amount of anterior–posterior mandibular relapse less than 1 mm 1 year post-operatively compared with immediate post-operatively. Conclusion: The present study suggests that orthognathic surgery can be performed safely in the patients with preoperative condylar resorption. A further study with long-term follow up more than 1 year is necessary. O.116 Orthognatic surgery and microvascular reconstruction of maxillo-mandibular defects P. Gennaro1 , C. Carnevale1 , I. Aboh1 , V. Valentini2 . 1 Universit`a di Roma “La Sapienza” Maxillofacial Department, 2 Oral Surgery and Maxillofacial Department, Universit`a di Roma “Tor Vergata”, Italy Introduction: The refinement of microsurgical reconstructive techniques has improved the possibilities for the treatment of complex maxillo-mandibular defects. In these cases, as in those of major resections or youthful traumas as well as the cases of post-radiation scars, orthognatic surgery is a valid complement
Oral Presentations
Bisphosphonate related diseases
to microvascular reconstruction. This combination allows for a better aesthetic and functional result. Materials and Methods: Seven cases of patients afflicted with both grave bone defects and malocclusions underwent microvascular reconstruction and orthognatic surgery. Three of these cases had suffered defects on account of mandibular resection and radiotherapy. Two were the result of hemimandibulectomy during their growing years; one case was the result of a hemimaxillectomy and RT. Results: In all the cases, the combined microvascular/orthognatic surgery allowed for an improved aesthetic and functional aspect. Discussion: The paper presents the seven cases fully and discusses the advantages of this combined surgery. Particular attention is given to the order of the combined surgery (whether the orthognatic precedes microvascular or vice versa). This ordering should depend on the needs of each patient.
Tuesday, 12 September 2006, 14.30−15.40
Hall 3
Bisphosphonate related diseases O.117 Osteonecrosis of the jaw(s) associated with the use of bisphosphonates: An iatrogenic epidemic J. Schoenaers, B. Moerenhout, F. Combes. Department of Oral Pathology and Oral & Maxillofacial Surgery, Faculty of Medicine, Catholic University of Leuven, Belgium Iatrogenic disease in the oral cavity is ever increasing with the ageing of the population and the introduction of new treatment modalities. Biphophonates, used mainly in palliation for Kahler’s and metastatic disease to the bones, are associated with necrosis of the jaws (ONJ). Presently, bisphosphonates are widely used in the treatment of osteoporosis. They are known to be potent osteoclast inhibitors. ONJ is mainly reported when administering chronical IV highdose bisphosphonate therapy, often in combination with corticosteroids and cytostatics. We present a series of 38 patients with ONJ. The typical lesions vary from a non-healing mucosal wound to an exposed jawbone. Evaluation consisted in clinical, radiologic and radionucleide exams. Thirty-seven patients received high-dose intravenous therapy with either zolendronic acid or pamidronate or both. One patient received oral therapy with alendronate for the treatment for osteoporosis. In 27 patients the lower jaw, in 7 the upper jaw, and in 5 both jaws were affected. In 13 instances the epithelial defect had no traumatic antecedent. In 24 a tooth extraction and in 4 an irritation by a denture base was at the onset of ONJ. Oral hygiene, antiseptics antibiotics, and minimal debridement almost never achieved healing. The majority of these patients required surgical procedures to remove the involved bone, and the use of gap spanning reconstruction plates. In the upper jaws ONJ caused progressive loss of bone structures. Prevention of treatment refractory ONJ will be the challenge for the future.
33
O.118 Management of patients with bisphosphonatesinduced osteonecrosis R. Javadian, M. Shahla, E. Boutremans, I. Loeb. Department of Stomatology and Maxillofacial Surgery, CHU St-Pierre, Brussels, Belgium Introduction: Intravenous nitrogen containing bisphosphonates (BP) are widely used in the management of bone metastasis, hypercalcemia associated with malignancies and osteoporosis (long-term corticotherapy). Osteonecrosis-induced bisphosphonates is a dreadful side effect frequently apparent within a few months of use, with a mean occurrence in 6.7% of cases. However, this rate is rising rapidly in line with the increasing interest in BP mainly in major bone metastasis and the underlying inadequate oral and dental hygiene. Material and Methods: Within the past 6 months, a total number of 12 patients, 8 females and 4 males, were referred to our institution with necrotic lesions of the jaws together with suppuration, pain and exposed jawbone. Eleven patients had been receiving intravenous BP and, one oral BP chronically at admission between 12 and 120 months. Results: Nine (75%) patients presented a periodontal disorder. Seven patients had non-healing extraction socket. Three (25%) patients had spontaneous lesions and one presented a maladapted prosthesis. We observed a total of 16 necrosis sites in our series of which 10 (62.5%) were in the mandible and 6 (37.5%) in the maxilla. All patients benefited of a conservative therapy (CT). Surgical procedures were performed on the involved bone in 4 (33%) patients. Symptoms receded in 2 patients with gingival healing of the lesions only treated with CT. However this was not the case of patients requiring bone surgery. Conclusion: We therefore conclude that oro-dental preventive therapy in the treatment of BP osteonecrosis within our guidelines is a more viable and only alternative to surgical treatments. O.119 Six months follow-up results after therapy of osteonecrosis of the jaws under bisphosphonates A. Wutzl, C. Klug, G. Millesi-Schobel, A. Baumann. Department of Craniomaxillofacial and Oral Surgery, Medical University, Vienna, Austria Introduction and Objectives: Osteonecrosis of the jaws is described as an intraoral complication after administration of intravenously administered nitrogen containing bisphosphonates. At the moment there are about 300 published cases worldwide. However, clinical trials evaluating treatment strategies are still missing. Materials and Methods: We included in this study 20 patients with osteonecrosis of the jaws after bisphosphonate treatment, who were treated surgically in our department between July 2004 and June 2005. All patients had a malignant disease with osteolytic lesions. The median number of treatment cycles for pamidronate was 36 times. Zolendric acid was given 23.5 times. Six months post-operative patients were examined concerning wound healing, pain score, prosthetic rehabilitation and complications. For diagnostic evaluation a computertomography was done in all patients at the follow-up. Results: Seventeen patients were treated with sequestrectomy and decortication in general anaesthesia. In three patients minor surgical procedures were done. At the 6 month follow-up 10 patients showed intact oral mucosa, were free of pain and prosthetically rehabilitated. Ten patients had developed a recurrence of the mucosal lesion, suffered from