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DCE-MRI to Evaluate Vascularization in Calvarial Grafts
Oral Abstract Session 5 the rabbits were euthanatized. The forelimbs were removed, stripped of soft tissues, and prepared for analyses. Methods of Data Analysis: Animals have been followed up at regular intervals at 2, 4, 6 and 8 weeks postoperatively with radiographs. At 8 weeks computed tomography (CT) using a Scanco Medical AG CT 40 system followed by histological assessment was carried out. The percentage areas of the ulnar critical sized bone defect occupied by newly formed bone were calculated. Non-parametric tests were used and the significant level was considered at p⬍0.05. Results of Investigation: The CaP cements containing NanoCaPs were fabricated under neutral pH and all show the formation of nano-structured hydroxyapatite (HA). The cements also show excellent cell attachment and cellular migration results. Our results of the radiographical, micro-CT and histological assessments of the new regenerative bone showed that the addition of BMP-2 to the CaP-cement yielded higher bone regeneration compared to other groups. Subsequently the CaPcement group also yielded higher regeneration potential than the control of organic matrix alone. Conclusion: Based on our results the incorporation of BMP-2 bound to NanoCaP carriers in the CaP-cements does yield bone healing enhancement. The use of our smart porous biomaterials scaffolds designed to fulfill current scaffold design criteria thus appears to demonstrate promising results with regard to their use in long bones. Our current on-going research delves into the optimization of resorbable cements that are amenable to the addition of growth factors for craniofacial regeneration and reconstruction. References: D. Olton et al. Nanostructured calcium phosphates for non-viral gene delivery: influence of the synthesis parameters on transfection efficiency. Biomaterials 28, 1267 (Feb, 2007). P. Kumta, et al. Nanostructured calcium phosphates for biomedical applications: novel synthesis and characterization. Acta Biomater 1 (2005) (1), pp. 65-83
Extreme Osteolysis of the Maxilla and the Mandible: Presentation of Twenty Cases in a West African Population D. Tvedt: Mercy Ships, S. Khullar Godtfredsen Idiopathic osteolysis of the maxillofacial region is rarely reported and poorly understood. The authors would like to present a series of 20 cases of severe osteolysis related to the maxilla and mandible in a West African population. The material has been gathered over an 18 month period of time as the patients came to seek treatment at Mercy Ships Dental Clinic in Liberia and Benin. Possible causes are avascular necrosis related to sickle cell anaemia (Jones 1999 Acta Orthopædica Belgia; 65-1), e-50
bacterially induced bone destruction, disseminated bone tuberculosis (Basanagoudar, Gupta, Bahadur et al Acta Orthopædica Belgia 2001;67-5), Gorham’s disease (“vanishing bone syndrome”), nontuberculous mycobacteria, or a possible re-emerge of the historical condition of “Phossy Jaw” related to environmental contamination by phosphate products. The patients had received very little or no previous dental treatment and did not have access to any type of medical care. Most all presented with extreme facial swelling - many of which were already draining via an extra-oral fistula. Figure 1: Facial swelling and extra-oral drainage.
Figure 1: 15-yr-old male presenting with typical discharging sinus along the ascending ramus.
Sequestrectomy of the necrotic bone was performed in all cases. We present clinical photos and x-rays from the 20 cases. We discuss different hypotheses for the pathogenesis of this condition.
DCE-MRI to Evaluate Vascularization in Calvarial Grafts M.G. DuVal: University of Toronto Background: Tissue engineering is an emerging field with the goal of predictable regeneration of tissue without harvesting autogenous tissue. Progress in tissue engineering is limited by inability to create an adequate blood supply. There is no in-vivo method for imaging angiogenesis in the bony wound. In-vivo Dynamic Contrast Enhanced MRI (DCE-MRI) has been used to image angiogenesis in soft tissue applications. Objectives: 1. Evaluate an established scaffold (porcine HA-ACM) for use in a bony wound. 2. Describe normal healing and angiogenesis using DCE-MRI and correlate with histology and micro CT. 3. Determine the effect of the HA-ACM with and without VegF on bone formation and vascularization. AAOMS • 2010
Oral Abstract Session 5 Study design: Bilateral 15 mm critical sized defects were created in the parietal bones of 20 NZW rabbits. Defects were treated as follows: Group 1 (n⫽6) Void and HA-ACM. Group 2 (n⫽6) Void and Ha-ACM-VegF. Group 3 (n⫽6) Ha-ACM and Ha-ACM-VegF. Group 4 (n⫽2) Ha-ACM and Ha-ACM-VegF. The animals underwent MRI imaging at weeks 1, 2, 3, 6, and 12. The animals were sacrificed 12 weeks (Group 4 at 6 weeks) and the calvarial analyzed by microCT and histomorphometry. Results: The MRI was able to demonstrate changes in contrast related to vascularization of the grafted defects. Void defects healed normally with fibrous connective tissue. Inflammation was seen around the scaffold in all grafted defects. No additional bone formation was seen in ACM or ACM-VegF groups compared to controls. Conclusions: DCE MRI is a novel and sensitive manner to study in vivo angiogenesis in grafted defects and should prove useful in evaluating candidate scaffolds and treatments on angiogenesis in bony or soft tissue applications. Porcine bladder HA-ACM is not a suitable material for grafting bony defects in its present form.
Jaw Tumors in Children S. Abramowicz: Harvard University, Children’s Hospital Boston, B. Goldwaser, M. Troulis, B. Padwa, L. Kaban Statement of the Problem: Jaw tumors in children are uncommon and few surgeons have extensive experience with their diagnosis and treatment. The purpose of this study was to evaluate management outcomes in two tertiary care academic hospitals during an 18 year period. Materials and Methods: Retrospective analysis of children with primary jaw tumors evaluated by the Oral and Maxillofacial Surgery Service at Massachusetts General and Children’s Hospital Boston from 1991 to 2009. Patient records, radiographs (plain films and computed tomograms), and pathology reports were reviewed. Demographic data (age at presentation, gender, race, duration of follow-up), tumor characteristics (clinical, radiographic and pathologic diagnosis), and treatment (operation, adjuvant therapy, reconstruction) were recorded. Outcome variables were complications and recurrences. Descriptive statistics were computed. Results of Investigation: There were 102 patients (44 males and 58 females) 16 years of age or younger, who presented for evaluation of a jaw swelling consistent with a tumor and who had adequate records for evaluation. The mean age was 8.3 years (range: 6 months - 16 years) and mean follow-up was 48 months (range: 2 months - 16 years). Tumors were classified as: mesenchymal (n⫽89), hematopoietic (n⫽3), neurogenic (n⫽5), or vascular (n⫽5). Mesenchymal tumors included: giant cell lesions (n⫽38; nonaggressive, n⫽11; aggressive, n⫽23; Noonan, n⫽4); osteochondroma (n⫽2); fibro-osseous lesions (n⫽35; fibrous dysplasia, n⫽14; cherubism, n⫽7; ossifying fibroma, AAOMS • 2010
n⫽11; osteoblastoma, n⫽3); myxofibroid lesions (n⫽14; myofibroma, n ⫽12; desmoplastic fibroma, n⫽1; fibromyxoma, n ⫽1). There were 26 maxillary and 69 mandibular tumors and 7 involved both jaws. Presenting symptoms included: swelling (n⫽49), discoloration (n⫽11), pain and tenderness (n⫽10), jaw asymmetry (n⫽8), tooth mobility (n⫽8) or displacement (n⫽7), trauma related or jaw fracture (n⫽5), delayed tooth eruption (n⫽3), bleeding (n⫽3), paresthesia (n⫽3), and incidental finding (n⫽20). Radiographic findings included mean size of 4.1 cm (range 1-10 cm), tooth and/or root displacement (n⫽30), cortical thinning (n⫽21), cortical perforation (n⫽19), bony expansion (n⫽14) and root resorption (n⫽8). Treatment was based on the tumor’s clinical/biologic behavior and whether it was solitary (n⫽74) or a multifocal process (n⫽28). Large tumors with rapid growth, bone resorption, root resorption or displacement were managed by en bloc resection (n⫽23) or enucleation with adjuvant therapy (n⫽19). Small tumors, discovered as an incidental radiographic finding, with no local invasion, destruction, tooth displacement, or root resorption were managed by enucleation/excision (n⫽35), enucleation ⫹ adjuvant peripheral ostectomy or cryotherapy/ embolization (n⫽9), debulking/contouring (n⫽14), or observation (n⫽3). Adjuvant local and/or systemic therapy at the time of intervention included interferon (n⫽24) or intra-lesional steroid (n⫽3). Recurrence rate was recorded by nature of tumor and treatment; 5/35 patients with aggressive tumors had recurrence (en bloc resection, 1/35; enucleation with adjuvant therapy, 2/35; and enucleation alone, 2/35). Patients with non-aggressive solitary tumors had no recurrence regardless of treatment. Conclusion: Jaw tumors in children often exhibit rapid growth, local invasion and tissue destruction which may not correlate with their “benign” histologic appearance. Although large, rapidly growing, destructive lesions in children may have a benign histologic appearance they should be treated based on their clinical and biologic behavior. References: Chuong R, Kaban LB. Diagnosis and Treatment of Jaw Tumors in Children. J Oral Maxillofac Surg 43:323-332, 1985. Troulis MJ, Williams B, Kaban LB: Jaw Tumors in Children. In Kaban LB, Troulis MJ, editors: Pediatric Oral and Maxillofacial Surgery, Philadelphia, 2003.
Glandular Odontogenic Cysts: Diagnosis and Treatment Dilemma K.J. Patel: University of Maryland Medical Center, J. Basile, A. Salama, R. Ord, J. Brahim Statement of the Problem: Glandular odontogenic cyst (GOC) is a relatively rare lesion of the jaws. Due to e-51
Extreme Osteolysis of the Maxilla and the Mandible: Presentation of Twenty Cases in a West African Population D. Tvedt: Mercy Ships, S. Khullar Godtfredsen Idiopathic osteolysis of the maxillofacial region is rarely reported and poorly understood. The authors would like to present a series of 20 cases of severe osteolysis related to the maxilla and mandible in a West African population. The material has been gathered over an 18 month period of time as the patients came to seek treatment at Mercy Ships Dental Clinic in Liberia and Benin. Possible causes are avascular necrosis related to sickle cell anaemia (Jones 1999 Acta Orthopædica Belgia; 65-1), e-50
bacterially induced bone destruction, disseminated bone tuberculosis (Basanagoudar, Gupta, Bahadur et al Acta Orthopædica Belgia 2001;67-5), Gorham’s disease (“vanishing bone syndrome”), nontuberculous mycobacteria, or a possible re-emerge of the historical condition of “Phossy Jaw” related to environmental contamination by phosphate products. The patients had received very little or no previous dental treatment and did not have access to any type of medical care. Most all presented with extreme facial swelling - many of which were already draining via an extra-oral fistula. Figure 1: Facial swelling and extra-oral drainage.
Figure 1: 15-yr-old male presenting with typical discharging sinus along the ascending ramus.
Sequestrectomy of the necrotic bone was performed in all cases. We present clinical photos and x-rays from the 20 cases. We discuss different hypotheses for the pathogenesis of this condition.
DCE-MRI to Evaluate Vascularization in Calvarial Grafts M.G. DuVal: University of Toronto Background: Tissue engineering is an emerging field with the goal of predictable regeneration of tissue without harvesting autogenous tissue. Progress in tissue engineering is limited by inability to create an adequate blood supply. There is no in-vivo method for imaging angiogenesis in the bony wound. In-vivo Dynamic Contrast Enhanced MRI (DCE-MRI) has been used to image angiogenesis in soft tissue applications. Objectives: 1. Evaluate an established scaffold (porcine HA-ACM) for use in a bony wound. 2. Describe normal healing and angiogenesis using DCE-MRI and correlate with histology and micro CT. 3. Determine the effect of the HA-ACM with and without VegF on bone formation and vascularization. AAOMS • 2010
Oral Abstract Session 5 Study design: Bilateral 15 mm critical sized defects were created in the parietal bones of 20 NZW rabbits. Defects were treated as follows: Group 1 (n⫽6) Void and HA-ACM. Group 2 (n⫽6) Void and Ha-ACM-VegF. Group 3 (n⫽6) Ha-ACM and Ha-ACM-VegF. Group 4 (n⫽2) Ha-ACM and Ha-ACM-VegF. The animals underwent MRI imaging at weeks 1, 2, 3, 6, and 12. The animals were sacrificed 12 weeks (Group 4 at 6 weeks) and the calvarial analyzed by microCT and histomorphometry. Results: The MRI was able to demonstrate changes in contrast related to vascularization of the grafted defects. Void defects healed normally with fibrous connective tissue. Inflammation was seen around the scaffold in all grafted defects. No additional bone formation was seen in ACM or ACM-VegF groups compared to controls. Conclusions: DCE MRI is a novel and sensitive manner to study in vivo angiogenesis in grafted defects and should prove useful in evaluating candidate scaffolds and treatments on angiogenesis in bony or soft tissue applications. Porcine bladder HA-ACM is not a suitable material for grafting bony defects in its present form.
Jaw Tumors in Children S. Abramowicz: Harvard University, Children’s Hospital Boston, B. Goldwaser, M. Troulis, B. Padwa, L. Kaban Statement of the Problem: Jaw tumors in children are uncommon and few surgeons have extensive experience with their diagnosis and treatment. The purpose of this study was to evaluate management outcomes in two tertiary care academic hospitals during an 18 year period. Materials and Methods: Retrospective analysis of children with primary jaw tumors evaluated by the Oral and Maxillofacial Surgery Service at Massachusetts General and Children’s Hospital Boston from 1991 to 2009. Patient records, radiographs (plain films and computed tomograms), and pathology reports were reviewed. Demographic data (age at presentation, gender, race, duration of follow-up), tumor characteristics (clinical, radiographic and pathologic diagnosis), and treatment (operation, adjuvant therapy, reconstruction) were recorded. Outcome variables were complications and recurrences. Descriptive statistics were computed. Results of Investigation: There were 102 patients (44 males and 58 females) 16 years of age or younger, who presented for evaluation of a jaw swelling consistent with a tumor and who had adequate records for evaluation. The mean age was 8.3 years (range: 6 months - 16 years) and mean follow-up was 48 months (range: 2 months - 16 years). Tumors were classified as: mesenchymal (n⫽89), hematopoietic (n⫽3), neurogenic (n⫽5), or vascular (n⫽5). Mesenchymal tumors included: giant cell lesions (n⫽38; nonaggressive, n⫽11; aggressive, n⫽23; Noonan, n⫽4); osteochondroma (n⫽2); fibro-osseous lesions (n⫽35; fibrous dysplasia, n⫽14; cherubism, n⫽7; ossifying fibroma, AAOMS • 2010
n⫽11; osteoblastoma, n⫽3); myxofibroid lesions (n⫽14; myofibroma, n ⫽12; desmoplastic fibroma, n⫽1; fibromyxoma, n ⫽1). There were 26 maxillary and 69 mandibular tumors and 7 involved both jaws. Presenting symptoms included: swelling (n⫽49), discoloration (n⫽11), pain and tenderness (n⫽10), jaw asymmetry (n⫽8), tooth mobility (n⫽8) or displacement (n⫽7), trauma related or jaw fracture (n⫽5), delayed tooth eruption (n⫽3), bleeding (n⫽3), paresthesia (n⫽3), and incidental finding (n⫽20). Radiographic findings included mean size of 4.1 cm (range 1-10 cm), tooth and/or root displacement (n⫽30), cortical thinning (n⫽21), cortical perforation (n⫽19), bony expansion (n⫽14) and root resorption (n⫽8). Treatment was based on the tumor’s clinical/biologic behavior and whether it was solitary (n⫽74) or a multifocal process (n⫽28). Large tumors with rapid growth, bone resorption, root resorption or displacement were managed by en bloc resection (n⫽23) or enucleation with adjuvant therapy (n⫽19). Small tumors, discovered as an incidental radiographic finding, with no local invasion, destruction, tooth displacement, or root resorption were managed by enucleation/excision (n⫽35), enucleation ⫹ adjuvant peripheral ostectomy or cryotherapy/ embolization (n⫽9), debulking/contouring (n⫽14), or observation (n⫽3). Adjuvant local and/or systemic therapy at the time of intervention included interferon (n⫽24) or intra-lesional steroid (n⫽3). Recurrence rate was recorded by nature of tumor and treatment; 5/35 patients with aggressive tumors had recurrence (en bloc resection, 1/35; enucleation with adjuvant therapy, 2/35; and enucleation alone, 2/35). Patients with non-aggressive solitary tumors had no recurrence regardless of treatment. Conclusion: Jaw tumors in children often exhibit rapid growth, local invasion and tissue destruction which may not correlate with their “benign” histologic appearance. Although large, rapidly growing, destructive lesions in children may have a benign histologic appearance they should be treated based on their clinical and biologic behavior. References: Chuong R, Kaban LB. Diagnosis and Treatment of Jaw Tumors in Children. J Oral Maxillofac Surg 43:323-332, 1985. Troulis MJ, Williams B, Kaban LB: Jaw Tumors in Children. In Kaban LB, Troulis MJ, editors: Pediatric Oral and Maxillofacial Surgery, Philadelphia, 2003.
Glandular Odontogenic Cysts: Diagnosis and Treatment Dilemma K.J. Patel: University of Maryland Medical Center, J. Basile, A. Salama, R. Ord, J. Brahim Statement of the Problem: Glandular odontogenic cyst (GOC) is a relatively rare lesion of the jaws. Due to e-51