Harutsugi Abukawa

Publications of Harutsugi Abukawa

• Application of custom-made bioresorbable raw particulate hydroxyapatite/poly-l-lactide mesh tray with particulate cellular bone and marrow and platelet-rich plasma for a mandibular defect: Evaluation of tray fit and bone quality in a dog model.

  Authors: Akira Matsuo, Hidetoshi Takahashi, Harutsugi Abukawa, Daichi Chikazu

  Journal of cranio-maxillo-facial surgery : official publication of the European Association for Cranio-Maxillo-Facial Surgery. 04/2012;

  The purpose of this study was to evaluate tray fit and bone quality of particulate cancellous bone and marrow (PCBM) mandibular reconstruction using custom-made bioresorbable forged composites of aThe purpose of this study was to evaluate tray fit and bone quality of particulate cancellous bone and marrow (PCBM) mandibular reconstruction using custom-made bioresorbable forged composites of a raw particulate hydroxyapatite/poly-l-lactide (HA/PLLA) tray in a dog model. Mesh sheets of HA/PLLA were formed in a tray shape according to the mandible stereolithographs of 14 beagle dogs. Platelet-rich plasma (PRP) was obtained from venous blood, and PCBM was harvested from the iliac crest. Bone defects were made bilaterally on the lower borders of the mandible. The PCBM and PRP were mixed and compressed into the defects and a custom-made HA/PLLA or a manually adopted titanium tray was fixed by screws. Tray fit and bone qualities were evaluated using computed tomography, microfocus computed tomography and confocal laser scanning microscopy. In buccal side, there is no significant difference with tray fit between the HA/PLLA and the titanium type, but in lingual side, it was better in the HA/PLLA type than that of the Ti type. Bone volume fraction (BV/TV) had markedly increased on the HA/PLLA side at 12 months. In conclusion, the custom-made HA/PLLA tray was easily and accurately adapted to the mandible, and had achieved sufficient bone quality by 12 months.

• Ultrasound-Guided Intralesional Photocoagulation of Intramuscular Vascular Malformation in the Masseter Muscle.

  Authors: Harutsugi Abukawa, Masato Watanabe, Yusuke Asada, Takafumi Satomi, Akira Matsuo, Daichi Chikazu

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 02/2012;

• Three-Dimensionally Printed Polycaprolactone and β-Tricalcium Phosphate Scaffolds for Bone Tissue Engineering: An In Vitro Study.

  Authors: Basel Sharaf, Caroline B Faris, Harutsugi Abukawa, Srinivas M Susarla, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2011; 70(3):647-56.

  The purpose of this study was to evaluate porcine bone marrow-derived progenitor cell (pBMPC) proliferation and penetration into a novel 3-dimensionally printed scaffold. Four different tissueThe purpose of this study was to evaluate porcine bone marrow-derived progenitor cell (pBMPC) proliferation and penetration into a novel 3-dimensionally printed scaffold. Four different tissue engineering scaffolds to evaluate pBMPC proliferation and penetration were examined. Scaffolds were fabricated from polycaprolactone (PCL) or the combination of β-tricalcium phosphate (β-TCP) and PCL (50:50), with 2 separate channel sizes (1 mm [small (S)] vs 2 mm [large (L)]). Scaffolds were fabricated into 20 × 20 × 7-mm blocks by use of a TheriForm machine (Integra Life Sciences, Akron, OH). Four groups of scaffolds were examined for pBMPC proliferation and penetration: group 1, β-TCP/PCL S; group 2, β-TCP/PCL L; group 3, PCL S; and group 4, PCL L. Nonparametric mean (Kruskal-Wallis) and multiple comparisons tests were used to compare the 4 groups. No shrinkage or deformation was noted in any of the scaffold groups after 2 weeks of culture. Mean surface cell counts ranged from 13.4 to 87.8 cells/0.57 mm(2), with group 1 (β-TCP/PCL S) having statistically significantly higher counts than the other groups (P < .001). Mean interior cell counts ranged from 10.9 to 75.6 cells/0.57 mm(2), with group 1 having the greatest interior cell count (P < .001). Total collagen formation ranged from 0.2% to 86%, with group 1 having the highest collagen formation (P < .001). The 3-dimensionally printed scaffold (β-TCP/PCL) with 1-mm channels showed greater cellular proliferation, penetration, and collagen formation after a 2-week in vitro culture than the other scaffolds evaluated. β-TCP/PCL S scaffolds warrant further evaluation for bone tissue engineering in vivo.

• Mandibular reconstruction using a tray with particulate cancellous bone and marrow and platelet-rich plasma by an intraoral approach.

  Authors: Akira Matsuo, Hiroshige Chiba, Jun Toyoda, Harutsugi Abukawa, Ko Fujikawa, Masako Tsuzuki, Masato Watanabe

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 01/2011; 69(6):1807-14.

  To evaluate the possibility of immediate mandibular reconstruction using particulate cancellous bone and marrow (PCBM), platelet-rich plasma (PRP), and a tray, we compared the postsurgical infectionTo evaluate the possibility of immediate mandibular reconstruction using particulate cancellous bone and marrow (PCBM), platelet-rich plasma (PRP), and a tray, we compared the postsurgical infection rate and bone formation in patients who received mandibular reconstruction with this method using either an intraoral or extraoral approach. We conducted a retrospective study of a series of 18 patients who underwent the mandibular reconstruction procedure using a mesh tray with PCBM and PRP, all performed by 1 surgeon. These cases were further divided into those treated by the intraoral approach and those treated by the extraoral approach. Clinical data, postoperative bone formation, and complications in the 2 groups were evaluated. The χ(2) examination and the Mann-Whitney U test were used for statistical analysis. We could not detect any statistically significant differences in clinical data between the 2 groups, except for the timing of reconstruction. There were postoperative complications such as wound dehiscence and tray exposure, as well as infection of the reconstructed bone. The overall complication rate of the recipient sites in the intraoral group was 30% (3 of 10), whereas in the extraoral group, it was 0%. However, satisfactory bone formation was seen in all cases in the intraoral group (100% [10 of 10]) but only 87.5% (7 of 8) in the extraoral group. We conclude that mandibular reconstruction using a tray with PCBM and PRP is a safe and reliable method for cases of benign tumor and trauma, even if immediate reconstruction is performed by an intraoral approach.

• Clinical application of a custom-made bioresorbable raw particulate hydroxyapatite/poly-L-lactide mesh tray for mandibular reconstruction.

  Authors: Akira Matsuo, Hiroshige Chiba, Hidetoshi Takahashi, Jun Toyoda, Harutsugi Abukawa

  Odontology / the Society of the Nippon Dental University. 02/2010; 98(1):85-8.

  Mandibular reconstruction using particulate cancellous bone and marrow (PCBM) allows functional oral reconstruction. Although ready-made titanium trays are the most common material used in thisMandibular reconstruction using particulate cancellous bone and marrow (PCBM) allows functional oral reconstruction. Although ready-made titanium trays are the most common material used in this method, they have some disadvantages such as difficulty in making them form a suitable contour for the defect, and the need for removal. A forged composite of raw particulate hydroxyapatite (HA)/poly-L-lactide (PLLA) is a bioresorbable material that is stronger than pure PLLA and induces bone formation more rapidly. We present two cases successfully treated with custom-made bioresorbable HA/PLLA mesh trays for mandibular reconstruction. A 29-year-old woman with recurrent ameloblastoma and a 66-year-old man with a recurrent keratinized odontogenic tumor of the mandible gave informed consent for this reconstruction technique. Mesh sheets of HA/PLLA were customized by a rapid prototyping method based on computed tomography (CT) data. Marginal resection of the tumor was carried out, and PCBM was harvested from the bilateral posterior iliac crests. PCBM and platelet-rich plasma were transferred to the tray, and the tray was fixed rigidly with HA/PLLA screws. In the second case, dental implants were inserted. There has been no bone resorption for over 2 years since reconstruction in these two cases, and the inserted dental implants have been free from any complications 1 year after loading. The average CT value in Hounsfield units (HU) of the implant sites of two cases was 790. In conclusion, the customized HA/PLLA tray was easily adapted to the mandible, and fine bone quality was obtained. These cases show that this tray system contributed to functional oral rehabilitation with dental implants.

• Effect of ibuprofen on osteoblast differentiation of porcine bone marrow-derived progenitor cells.

  Authors: Harutsugi Abukawa, Maynard Phelps, Pamela Jackson, R Malcolm Smith, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 11/2009; 67(11):2412-7.

  PURPOSE: Nonsteroidal anti-inflammatory drugs are commonly prescribed to reduce inflammation and pain. However, little is known about the direct effect of these drugs on the differentiation of bonePURPOSE: Nonsteroidal anti-inflammatory drugs are commonly prescribed to reduce inflammation and pain. However, little is known about the direct effect of these drugs on the differentiation of bone marrow-derived progenitor cells into osteoblasts. The purpose of this study was to determine the effect of ibuprofen on osteoblast differentiation and proliferation in a minipig model. MATERIALS AND METHODS: Bone marrow was aspirated from the minipig ilium, and porcine bone marrow-derived progenitor cells (pBMPCs) were isolated and expanded in standard culture medium. The pBMPCs were replated and differentiated into osteoblasts by use of osteogenic supplements (OS). Five groups were studied: negative control--pBMPCs in standard medium only; positive control--pBMPCs, standard culture medium, and OS; and 3 experimental groups--pBMPCs, standard culture medium, OS, and ibuprofen added in doses of 0.1, 1.0, and 3.0 mmol/L. Cell cultures were evaluated quantitatively by alkaline phosphatase (ALP) stain, von Kossa stain, and deoxyribonucleic acid (DNA) content. RESULTS: pBMPCs cultured with OS and low-dose ibuprofen (0.1 mmol/L) showed ALP stain, von Kossa stain, and DNA content similar to pBMPCs cultured in OS (positive control). pBMPCs cultured in higher doses of ibuprofen (1.0 and 3.0 mmol/L) produced significantly less positive staining of ALP and von Kossa and decreased DNA content. CONCLUSION: The results indicate that high-dose ibuprofen has a deleterious effect on pBMPC differentiation into osteoblasts whereas low-dose ibuprofen does not. The low dose of 0.1 mmol/L is the typical serum level when prescribed for clinical use.

• Reconstructing mandibular defects using autologous tissue-engineered tooth and bone constructs.

  Authors: Harutsugi Abukawa, Weibo Zhang, Conan S Young, Rose Asrican, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis, Pamela C Yelick

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 03/2009; 67(2):335-47.

  PURPOSE: Current strategies for jaw reconstruction require multiple operations to replace bone and teeth. To improve on these methods, we investigated simultaneous mandibular and toothPURPOSE: Current strategies for jaw reconstruction require multiple operations to replace bone and teeth. To improve on these methods, we investigated simultaneous mandibular and tooth reconstruction, using a Yucatan minipig model. MATERIALS AND METHODS: Tooth and bone constructs were prepared from third molar tooth tissue and iliac-crest bone marrow-derived osteoblasts isolated from, and implanted back into, the same pig as an autologous reconstruction. Implants were harvested after 12 and 20 weeks and evaluated by x-ray, ultrahigh-resolution volume computed tomographic (VCT), histological, and immunohistochemical analyses. RESULTS: Small tooth structures were identified, and consisted of organized dentin, enamel, pulp, and periodontal ligament tissues, surrounded by new bone. No dental tissues formed in implants without tooth-bud cells, and bone regeneration was observed to a limited extent. Immunohistochemical analyses using tooth-specific and bone-specific antibodies confirmed the identity of regenerated tissues. CONCLUSIONS: This pilot study supports the feasibility of tissue-engineering approaches for coordinated autologous tooth and mandible reconstruction, and provides a basis for future improvement of this technique for eventual clinical use in humans.

• Tissue engineered hybrid tooth-bone constructs.

  Authors: Weibo Zhang, Harutsugi Abukawa, Maria J Troulis, Leonard B Kaban, Joseph P Vacanti, Pamela C Yelick

  Methods (San Diego, Calif.). 11/2008;

  Proper rehabilitation of craniofacial defects is challenging because of the complexity of the anatomy and the component tissue types. The ability to simultaneously coordinate the regeneration ofProper rehabilitation of craniofacial defects is challenging because of the complexity of the anatomy and the component tissue types. The ability to simultaneously coordinate the regeneration of multiple tissues would make reconstruction more efficient and might reduce morbidity and improve outcomes. The craniofacial complex is unique because of the presence of teeth, in addition to skin, bone, cartilage, muscle, vascular, and neural tissues since teeth naturally grow in coordination with the craniofacial skeleton, our group developed an autologous, tooth-bone hybrid model to facilitate repair of mandibular defects in the Yucatan minipig. The hybrid tooth-bone construct was prepared by combining tooth bud cell-seeded scaffolds with autologous iliac crest bone marrow derived stem cell-seeded scaffolds, which were transplanted back into surgically created mandibular defects in the same minipig. The constructs were harvested after 12 and 20 weeks of growth. The resulting bone/tooth constructs were evaluated by X-ray, ultra high-resolution volume computed tomography (VCT), histological, immunohistochemical analyses, and transmission electron microscopy (TEM). The observed formation of small tooth-like structures consisting of organized dentin, enamel, pulp, cementum, periodontal ligament, and surrounded by regenerated alveolar bone, suggests the feasibility for regeneration of teeth and associated alveolar bone, in a single procedure. This model provides an accessible method for future clinical applications in humans.

• Development of a biodegradable scaffold with interconnected pores by heat fusion and its application to bone tissue engineering.

  Authors: Michael Shin, Harutsugi Abukawa, Maria J Troulis, Joseph P Vacanti

  Journal of biomedical materials research. Part A. 04/2008; 84(3):702-9.

  Tissue engineering has been proposed as an approach to alleviate the shortage of donor tissue and organs by combining cells and a biodegradable scaffold as a temporary extracellular matrix. WhileTissue engineering has been proposed as an approach to alleviate the shortage of donor tissue and organs by combining cells and a biodegradable scaffold as a temporary extracellular matrix. While numerous scaffold fabrication methods have been proposed, tissue formation is typically limited to the surface of the scaffolds in bone tissue engineering applications due to early calcification on the surface. To improve tissue formation, a novel scaffold with a hierarchical interconnected pore structure on two distinct length scales has been developed. Here we present the fabrication process and the application of the scaffold to bone tissue engineering. Porous poly(lactide-co-glycolide) (PLGA) scaffolds were made by combining solvent casting/particulate leaching with heat fusion. Porcine bone marrow-derived mesenchymal stem cells (MSCs) were differentiated into osteoblasts and cultured on these scaffolds in vitro for 2, 4, and 6 weeks. Subsequently, the constructs were assessed using histology and scanning electron microscopy. The bone marrow-derived osteoblasts attached well on these scaffolds. Cells were observed throughout the scaffolds. These initial results show promise for this scaffold to aid in the regeneration of bone.

• Hydrogel-beta-TCP scaffolds and stem cells for tissue engineering bone.

  Authors: Christian Weinand, Irina Pomerantseva, Craig M Neville, Rajiv Gupta, Eli Weinberg, Ijad Madisch, Frederic Shapiro, Harutsugi Abukawa, Maria J Troulis, Joseph P Vacanti

  Bone. 05/2006; 38(4):555-63.

  Trabecular bone is a material of choice for reconstruction after trauma and tumor resection and for correction of congenital defects. Autologous bone grafts are available in limited shapes and sizes;Trabecular bone is a material of choice for reconstruction after trauma and tumor resection and for correction of congenital defects. Autologous bone grafts are available in limited shapes and sizes; significant donor site morbidity is another major disadvantage to this approach. To overcome these limitations, we used a tissue engineering approach to create bone replacements in vitro, combining bone-marrow-derived differentiated mesenchymal stem cells (MSCs) suspended in hydrogels and 3-dimensionally printed (3DP) porous scaffolds made of beta-tricalcium-phosphate (beta-TCP). The scaffolds provided support for the formation of bone tissue in collagen I, fibrin, alginate, and pluronic F127 hydrogels during culturing in oscillating and rotating dynamic conditions. Histological evaluation including toluidine blue, alkaline phosphatase, and von Kossa staining was done at 1, 2, 4, and 6 weeks. Radiographic evaluation and high-resolution volumetric CT (VCT) scanning, expression of bone-specific genes and biomechanical compression testing were performed at 6 weeks. Both culture conditions resulted in similar bone tissue formation. Histologically collagen I and fibrin hydrogels specimens had superior bone tissue, although radiopacities were detected only in collagen I samples. VCT scan revealed density values in all but the Pluronic F127 samples, with Houndsfield unit values comparable to native bone in collagen I and fibrin glue samples. Expression of bone-specific genes was significantly higher in the collagen I samples. Pluronic F127 hydrogel did not support formation of bone tissue. All samples cultured in dynamic oscillating conditions had slightly higher mechanical strength than under rotating conditions. Bone tissue can be successfully formed in vitro using constructs comprised of collagen I hydrogel, MSCs, and porous beta-TCP scaffolds.

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• Formation of a mandibular condyle in vitro by tissue engineering.

  Authors: Harutsugi Abukawa, Hidetomi Terai, Didier Hannouche, Joseph P Vacanti, Leonard B Kaban, Maria J Troulis

  Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons. 02/2003; 61(1):94-100.

  PURPOSE: Mandibular reconstructive procedures often produce significant donor site morbidity. Recently, the use of minimally invasive techniques has been reported for mandibular reconstruction withPURPOSE: Mandibular reconstructive procedures often produce significant donor site morbidity. Recently, the use of minimally invasive techniques has been reported for mandibular reconstruction with decreased morbidity at the primary operative site. To date, these techniques have not addressed the graft donor site. We hypothesize that tissue-engineering techniques may be used to fabricate bone and thereby eliminate donor site morbidity. METHODS: Porcine mesenchymal stem cells (pMSCs) were isolated from the bone marrow of 3 Yucatan minipigs and grown in standard culture flasks. When they became near-confluent, cells were detached and replated with the addition of osteogenic supplements. A model of a porcine mandibular condyle was made and used to fabricate porous polymer scaffolds from biodegradable poly DL-lactic-co-glycolic acid (PLGA). Differentiated osteoblasts were transferred to the PLGA scaffold and cultured for 6 weeks in a rotational oxygen-permeable bioreactor system. The cultured constructs, consisting of scaffold and cells, were evaluated by gross, radiologic, and histologic examinations. RESULTS: The engineered constructs were white and hard and had a shape that closely resembled that of the model condyle. Plain radiographs demonstrated that the radiodensity of the construct was between that of the normal condyle and that of control scaffolds. Histologically, bone was observed on the entire surface of the PLGA scaffolds with an average thickness of 0.03 mm. Bone was not observed in the control scaffolds. CONCLUSION: In this pilot study, autologous tissue-engineered bone constructs were successfully made by combining biodegradable polymers and pMSCs.

• Osteoclastogenesis on tissue-engineered bone.

  Authors: Keisuke Nakagawa, Harutsugi Abukawa, Michael Y Shin, Hidetomi Terai, Maria J Troulis, Joseph P Vacanti

  Tissue engineering. 10(1-2):93-100.

  Bone remodeling plays an important role in bone function. To date, bone tissue-engineering research has focused primarily on bone formation from osteoblasts. This study demonstrates thatBone remodeling plays an important role in bone function. To date, bone tissue-engineering research has focused primarily on bone formation from osteoblasts. This study demonstrates that osteoclastogenesis can occur on a mineralized polymer scaffold. Porcine bone marrow-derived mesenchymal stem cells (pMSCs) and hematopoietic cells were isolated from the bone marrow of Yucatan minipigs (n = 3) and cultured separately. pMSCs were differentiated into osteoblasts, seeded on porous poly(D,L-lactic-co-glycolic acid) foams, and cultured in a rotating oxygen-permeable bioreactor system. Once the cell-polymer constructs had started to mineralize, the hematopoietic cells were added and cocultured to include osteoclastogenesis. The cultured constructs were evaluated by histochemical and microscopic examination. Our results show that osteoblasts and osteoclasts were successfully differentiated from bone marrow on the scaffolds. This is the first demonstration of osteoclast formation on mineralized polymer surfaces.

• Tissue-engineered hybrid tooth and bone.

  Authors: Conan S Young, Harutsugi Abukawa, Rose Asrican, Michael Ravens, Maria J Troulis, Leonard B Kaban, Joseph P Vacanti, Pamela C Yelick

  Tissue engineering. 11(9-10):1599-610.

  Tooth loss accompanied by alveolar bone resorption presents a significant clinical problem. We have investigated the utility of a tissue-engineering approach to provide corrective therapies forTooth loss accompanied by alveolar bone resorption presents a significant clinical problem. We have investigated the utility of a tissue-engineering approach to provide corrective therapies for tooth-bone loss. Hybrid tooth-bone tissues were bioengineered as follows. Tooth implants were generated from pig third molar tooth bud cells seeded onto polyglycolide (PGA) and polyglycolide-colactide (PLGA) scaffolds, and grown for 4 weeks in the omenta of adult rat hosts. Bone implants were generated from osteoblasts induced from bone marrow progenitor cells obtained from the same pig, seeded onto PLGA fused wafer scaffolds, and grown for 10 days in a rotational oxygen-permeable bioreactor system. The tooth and bone implants were harvested, sutured together, reimplanted, and grown in the omenta for an additional 8 weeks. Histological and immunohistochemical analyses of the excised hybrid tooth-bone constructs revealed the presence of tooth tissues, including primary and reparative dentin and enamel in the tooth portion of hybrid tooth-bone implants, and osteocalcin and bone sialoprotein-positive bone in the bone portion of hybrid tooth-bone constructs. Collagen type III-positive connective tissue resembling periodontal ligament and tooth root structures were present at the interface of bioengineered tooth and bone tissues. These results demonstrate the utility of a hybrid tooth-bone tissue-engineering approach for the eventual clinical treatment of tooth loss accompanied by alveolar bone resorption.