Huakun (Hockin) Xu. PhD, MS.

Associate Professor
Department of Endodontics, Prosthodontics and Operative Dentistry, Dental School.
Member, Center for Stem Cell Biology & Regenerative Medicine, School of Medicine.
University of Maryland, Baltimore, MD 21201

Room: 6257
Tel: 410-706-6887.
Email:hxu@umaryland.edu

Teaching Activity:

• Course Director, Dental Biomaterials I (BMAT 518) for Year 1 dental students.
• Course Director, Dental Biomaterials II (BMAT 528) for Year 2 dental students.
• Course Director, Adv Dent Mater (Pros 598A) for dental residents.

Research Team (Full Time):

• Michael D. Weir, PhD, Research Assistant Professor.
• Jennifer L. Moreau, MS, Research Assistant.
• Ryan Zhao, PhD, MD, Postdoctoral Scientist.
• Minghui Tang, PhD, DDS, Postdoctoral Scientist.
• Wahwah Thien-Han, MD, PhD, Postdoctoral Scientist.

Research Interests:

• Tissue engineering, bone regeneration, dental and craniofacial repair, bioactive and resorbable scaffolds, biomimetic and injectable carriers, stem cells, growth factor delivery.
• Dental materials, nanocomposites, tooth restorations, caries inhibition, fluoride-based materials, calcium phosphate biomaterials, smart biocomposites, controlled release.

Grants:

Ongoing Grants:

NIH R01 DE14190. PI: Huakun Xu.

• 04/01/2009 - 03/31/2014.
• $1.84 million.
• “Injectable and Strong Nano-Apatite/Stem Cell Scaffolds for Bone Regeneration.”

NIH R01 DE17974. PI: Huakun Xu.

• 04/01/2008 - 03/31/2012.
• $1.05 million.
• “Development of High Performance, Caries-Inhibiting Dental Nano-Materials.”

Maryland Stem Cell Research Fund (MSCRF). PI: Huakun Xu.

• 07/01/2008 – 06/31/2010.
• $230,000.
• “Stem Cell Delivery via Injectable, Nano-Apatite Scaffolds for Bone Engineering.”

NIH R01 DE14190-07-S1. Competitive Revision Supplement.

• PI: Huakun Xu.
• 10/01/2009 - 9/31/2011.
• $430,000.

Completed:

NIH R01 DE14190.

• PI: Huakun Xu.
• 04/01/2003 - 03/31/2009.
• $1.24 million.
• “Development of Strong and Macroporous Biomaterials.”

State of Maryland Nano-Biotechnology Initiative Award.

• PI: Huakun Xu.
• $200,000.
• Department of Business and Economic Development (DBED) of Maryland. 7/1/2007 – 6/30/2008.

NIH R29 DE12476

• PI: Huakun Xu
• 09/01/1998 - 07/31/2004.
• $499,593.
• “Ceramic Whisker Reinforcement of Dental Resin Composites.”

Periodontal Bone Tissue Engineering.

• PI: Huakun Xu.
• ADAF research grant, $67,520, 2004-2005.

Review and Service:

• 2007-present Editorial Board Member, Dental Materials.
• 2008-present Editorial Board Member, Journal of Biomedical Materials Res (B).
• 2006-2008 Editorial Board Member, Journal of Dental Research.
• 1998-present Reviewer, J Dent Res, Dent Mater, Biomaterials, J Biomed Mater Res, Tissue Engineering, etc.
• 2000-2009 Oral Session Chair, AADR/IADR.
• 2005 IADR Dental Materials Group Ceramics & Cement Program Chair.
• 2005, 2007 AADR Abstract Reviewer.
• 2008 AADR/IADR Dental Materials Group Symposium Organizer.
• 2009-present Fellow, Academy of Dental Materials.

Patents:

• Xu HHK, Eichmiller FC. Reinforcement of dental and other composites. U. S. Patent No. 5,861,445, 1999.
• Xu HHK, Eichmiller FC, Schumacher GE. Continuous fiber-reinforced dental restorations. U. S. Patent No. 6,334,775, 2002.
• Xu HHK, Chow LC, Takagi S, Eichmiller FC. Self-hardening calcium phosphate materials with high resistance to fracture, controlled strength histories and tailored macropore formation rates. U.S. Patent No. 6,955,716, 2005.
• Xu HHK, Weir M. Three-Dimensional Cell Protector/Pore Architecture Formation for Bone and Tissue Constructs. U.S. Patent No. 11/132,028, allowed Nov. 25, 2009.
• Xu HHK, Sun L, Takagi S, Chow LC. Dental releasing materials. U. S. Patent No. 7,632,878, December 15, 2009.

Publications (after year 2000):

2010

• Xu HHK, Weir MD, Sun S, Moreau JL, Takagi S, Chow LC, Antonucci JM. Strong nanocomposites with Ca, PO4 and F release for caries inhibition. J Dent Res 2010;89:19-28.
• Zhao R, Burguera EF, Xu HHK, Amin N, Ryou H, Arola DD. Fatigue and human umbilical cord stem cell seeding characteristics of calcium phosphate–chitosan–biodegradable fiber scaffolds. Biomaterials 2010;31:840–847.
• Zhao L, Weir MD, Xu HHK. Human umbilical cord stem cell encapsulation in calcium phosphate scaffolds for bone engineering. Biomaterials (2010, accepted for publication).
• Xu HHK, Moreau JL, Sun L, Chow LC. Novel CaF2 nanocomposite with high strength and F ion release. J Dent Res (2010, accepted for publication).

2009

• Weir MD, Xu HHK. Culture human mesenchymal stem cells with calcium phosphate cement scaffolds for bone repair. J Biomed Mater Res B (2009, Accepted for publication).
• Weir MD, Xu HHK. Osteoblastic induction on calcium phosphate cement-chitosan constructs for bone tissue. J Biomed Mater Res A (2009, Accepted for publication).
• Xu HHK, Moreau JL. Dental glass-reinforced composite with calcium and phosphate ion release for caries inhibition. J Biomed Mater Res B (2009, Accepted for publication).
• Moreau JL, Xu HHK. Mesenchymal stem cell proliferation and differentiation on an injectable calcium phosphate-chitosan composite scaffold. Biomaterials 2009;30:2675-2682.
• Xu HHK, Weir MD, Sun L. Calcium and phosphate ion releasing composite: Effect of pH on release and mechanical properties. Dent Mater 2009;25:535-542.
• Moreau JL, Weir MD, Xu HHK. Self-setting collagen-calcium phosphate bone cement: Mechanical and cellular properties. J Biomed Mater Res A 2009;91:605-613.
• Xu HHK, Weir MD, Sun L, Ngai S, Takagi S, Chow LC. Effect of filler level and particle size on dental caries-inhibiting Ca-PO4 composite. J Mater Science: Mater in Medicine 2009;20:1771-1779.

2008

• Xu HHK, Moreau JL, Sun L, Chow LC. Strength and fluoride release characteristics of a calcium fluoride based dental nanocomposite. Biomaterials 2008;29:4261-4267.
• Xu HHK, Weir MD, Simon CG. Injectable and strong nano-apatite scaffolds for cell/growth factor delivery and bone regeneration. Dental Materials 2008;24:1212-1222.
• Weir MD, Xu HHK. High-strength, in situ-setting calcium phosphate composite with protein release. J Biomed Mater Res 2008;85A:388-396.
• Burguera EF, Xu HHK, Sun L. Injectable calcium phosphate cement: Effects of powder-to-liquid ratio and needle size. J Biomed Mater Res 2008;84B:493-502.

2007

• Xu HHK, Weir MD, Sun L, Takagi S, Chow LC. Effect of calcium phosphate nanoparticles on Ca-PO4 composites. J Dent Res 2007;86:378-383.
• Xu HHK, Sun L, Weir MD, Takagi S, Chow LC, Hockey B. Effects of nano-sized monocalcium phosphate monohydrate fillers on Ca-and-PO4-releasing dental composites. J Biomed Mater Res: Appl Biomater 2007;81B:116-125.
• Xu HHK, Carey LE, Simon CG Jr, Takagi S, Chow LC. Premixed calcium phosphate cements: synthesis, physical properties, and cell cytotoxicity. Dental Materials 2007;23:433-441.
• Sun L, Xu HHK, Takagi S, Chow LC. Fast setting CPC-chitosan composite: Mechanical properties and dissolution rates. J Biomater Appl 2007;21:299-315.
• Xu HHK, Weir MD, Sun L. Dental nanocomposites with Ca-PO4 release: Effects of reinforcement, dicalcium phosphate particle size and silanization. Dental Materials 2007;23:1482-1491.
• Xu HHK, Carey LE, Simon CG. Macroporous scaffold of premixed calcium phosphate bone cement: Mechanical properties and cell response. J Mater Sci: Mater in Medicine 2007;18:1345-1353.
• Xu HHK, Weir MD, Simon CG. In situ setting nano-apatite scaffolds: Load-bearing properties and delivery of cells and growth factors. Acad Dent Mater Trans 2007;21:14-29.
• Xu HHK, Carey LE, Burguera EF. Strong, macroporous, and in situ-setting calcium phosphate cement layered structures. Biomaterials 2007;28:3786-3796.

2006

• Xu HHK, Weir MD, Burguera EF, Fraser AM. Injectable and macroporous calcium phosphate cement scaffold. Biomaterials 2006;27:4279-4287.
• Xu HHK, Takagi S, Sun L, Hussain L, Chow LC, Guthrie WF, Yen JH. Calcium phosphate cement with non-rigidity and strength durability for periodontal bone repair. J Am Dent Assoc 2006;137:1131-1138.
• Burguera EF, Xu HHK, Weir MD. Injectable and rapid-setting calcium phosphate bone cement with dicalcium phosphate dihydrate. J Biomed Mater Res 2006;77B:126-134.
• Weir MD, Xu HHK, Simon CG. Strong calcium phosphate cement-chitosan-mesh construct containing cell-encapsulating hydrogel beads for bone tissue engineering. J Biomed Mater Res 2006;77A:487-496.
• Zhang Y, Xu HHK, Takagi S, Chow LC. In-situ hardening hydroxyapatite-based scaffold for bone repair. J Mater Sci: Mater in Medicine 2006;17:437-445.
• Xu HHK, Sun L, Weir MD, Antonucci JM, Takagi S, Chow LC, Peltz M. Nano DCPA-whisker composites with high strength and Ca and PO4 release. Journal of Dental Research 2006;85:722-727.

2005

• Xu HHK, Simon CG Jr (2005). Fast setting calcium phosphate-chitosan scaffold: mechanical properties and biocompatibility. Biomaterials 2005;26:1337-1348.
• Xu HHK, Simon CG Jr, Takagi S, Chow LC, Eichmiller FC. Strong, macroporous and in-situ hardening hydroxyapatite for bone tissue engineering. Biomaterials Forum 2005;27:14-19.
• Burguera EF, Xu HHK, Takagi S, Chow LC (2005). High early-strength calcium phosphate bone cement: Effects of dicalcium phosphate dehydrate and absorbable fibers. J Biomed Mater Res 75A:966-975.
• Antonucci JM, Dickens SH, Fowler BO, Xu HHK, McNonough WG (2005). Chemistry of silanes: Interfaces in dental polymers and composites. J Res NIST 110:541-558.
• Zhang Y, Xu HHK (2005). Effects of synergistic reinforcement and absorbable fiber strength on hydroxyapatite bone cement. J Biomed Mater Res 75A:832-840.
• Carey LE, Xu HHK, Simon CG, Takagi S, Chow LC. Premixed rapid-setting calcium phosphate composites for bone repair. Biomaterials 2005;26:5002-5014.

2004

• Xu HHK, Quinn JB, Giuseppetti AA (2004). Wear and mechanical properties of nano-silica-fused whisker composites. Journal of Dental Research 2004;83:930-935.
• Xu HHK, Quinn JB, Giuseppetti AA, Eichmiller FC, Parry EE, Schumacher GE (2004). Three-body wear of dental resin composites reinforced with silica-fused whiskers. Dental Materials 20:220-227.
• Xu HHK, Quinn JB, Takagi S, Chow LC (2004). Synergistic reinforcement of in situ hardening calcium phosphate composite scaffold for bone tissue engineering. Biomaterials 25:1029-1037.
• Xu HHK, Simon CG (2004). Self-hardening calcium phosphate cement-mesh composite: Reinforcement, macropores, and cell response. J Biomed Mater Res 69A:267-278.
• Xu HHK, Takagi S, Quinn JB, Chow LC (2004). Fast-setting and anti-washout calcium phosphate scaffolds with high strength and controlled macropore formation rates. J Biomed Mater Res 68A:725-734.
• Xu HHK, Simon CG (2004). Self-hardening calcium phosphate composite scaffold for bone tissue engineering. Journal of Orthopaedic Research 22:535-543.
• Xu HHK, Smith DT, Simon CG (2004). Strong and bioactive composites containing nano-silica-fused whiskers for bone repair. Biomaterials 25:4615-4626.

2003

• Xu HHK, Quinn JB, Smith DT, Giuseppetti AA, Eichmiller FC (2003). Effects of different whiskers on the reinforcement of dental resin composites. Dent Mater 19:359-367.
• Xu HHK (2003). Long-term water aging of whisker-reinforced polymer-matrix composites. Journal of Dental Research 82:48-52.
• Xu HHK, Schumacher GE, Eichmiller FC, Peterson RC, Antonucci JM, Mueller HJ (2003). Continuous-fiber preform reinforcement of dental resin composite restorations. Dental Materials 19:523-530.

2002

• Xu HHK, Quinn JB, Takagi S, Chow LC (2002). Processing and properties of strong and non-rigid calcium phosphate cement. Journal of Dental Research 81:219-224.
• Xu HHK, Quinn JB (2002). Calcium phosphate cement containing resorbable fibers for short-term reinforcement and macroporosity. Biomaterials 23:193-202.
• Xu HHK, Eichmiller FC, Smith DT, Schumacher GE, Giuseppetti AA, Antonucci JM (2002). Effect of thermal cycling on whisker-reinforced dental resin composites. J Mater Sci: Mater in Medicine 13:875-883.
• Xu HHK, Quinn JB, Smith DT, Antonucci JM, Schumacher GE, Eichmiller FC (2002). Dental resin composites containing silica-fused whiskers – Effects of whisker-to-silica ratio on fracture toughness and indentation properties. Biomaterials 23:735-742.

2001

• Xu HHK, Quinn JB (2001). Effect of silicon carbide whisker-silica heat treatment on the reinforcement of dental resin composites. J Biomed Mater Res 58B:81-87.
• Xu HHK, Eichmiller FC, Barndt PR (2001). Effects of fiber length and volume fraction on the reinforcement of calcium phosphate cement. J Mater Sci: Mater Med 12:57-65.
• Xu HHK, Quinn JB (2001). Whisker-reinforced bioactive composites containing calcium phosphate cement fillers: Effects of filler ratio and surface treatments on mechanical properties. J Biomed Mater Res 57A:165-174.
• Xu HHK, Quinn JB, Takagi S, Chow LC, Eichmiller FC (2001). Strong and macroporous calcium phosphate cement: Effects of porosity and fiber reinforcement. J Biomed Mater Res 57A:457-466.

2000

• Xu HHK (2000). Whisker-reinforced heat-cured dental resin composites: Effects of filler level and heat-cure temperature and time. J Dent Res 79:1392-1397.
• Xu HHK, Eichmiller FC, Antonucci JM, Schumacher GE, Ives LK (2000). Dental resin composites containing ceramic whiskers and precured glass ionomer particles. Dent Mater 16:356-363.
• Xu HHK, Schumacher GE, Eichmiller FC, and Antonucci JM (2000). Strengthening composite resin restorations with ceramic whisker reinforcement. Pract Periodont Aesthet Dent 12:111-116.
• Xu HHK, Eichmiller FC, Antonucci JM, Flaim GM (2000). Single-crystalline ceramic whisker-reinforced carboxylic acid-resin composites with fluoride release. Operative Dentistry 25:90-97.
• Xu HHK, Smith DT, Schumacher GE, Eichmiller FC, Antonucci JM (2000). Indentation modulus and hardness of whisker-reinforced heat-cured dental resin composites. Dent Mater 16:248-254.
• Xu HHK, Eichmiller FC, Giuseppetti AA (2000). Reinforcement of a self-setting calcium phosphate cement with different fibers. J Biomed Mater Res 52:107-114.
• Xu HHK, Smith DT, Schumacher GE, Eichmiller FC (2000). Whisker-reinforced dental core buildup composites: Effect of filler level on mechanical properties. J Biomed Mater Res 52:812-818.
• Xu HHK, Quinn JB, Giuseppetti AA, Eichmiller FC (2000). Effects of whisker-to-silica ratio on the reinforcement of dental resin composites with silica-fused whiskers. J Dent Res 79:1844-1849.