Review of bone substitutes

Abstract

Bone substitutes are being increasingly used in craniofacial surgery and craniomaxillofacial trauma. We will review the history of the biomaterials and describe the ideal characteristics of bone substitutes, with a specific emphasis on craniofacial reconstruction. Some of the most commonly used bone substitutes are discussed in more depth, such as calcium phosphate and hydroxyapatite ceramics and cements, bioactive glass, and polymer products. Areas of active research and future directions include tissue engineering, with an increasing emphasis on bioactivity of the implant.

Keywords: Bone substitutes; biomaterials; calcium phosphate cements; hydroxyapatite; polymethylmethacrylate; porous polyethylene.

Figure 1

(A and B) Masseteric hypertrophy and vertical microgenia. Correction was performed by gonial angle resection bilaterally and vertical lengthening genioplasty using block hydroxyapatite. Front and profile views after surgery. (C and D) Frontal and profile views 8 years later. (E) Intraoperative view of vertical lengthening genioplasty using block hydroxyapatite. (Reprinted with permission from Zins JE, et al. Contour alteration of the facial skeleton. In: Achauer BM, Guyuron B, eds. Plastic Surgery: Indications, Operatons, Outcomes. Philadelphia: Elsevier; 2000:2824. Copyright Elsevier 2000.)

Figure 2

(A and B) A 55-year-old man who presented with a decrease in his lower vertical facial height due to vertical microgenia. Postoperative (C) frontal and (D) profile views following vertical lengthening genioplasty and interposition implant of tricalcium phosphate. (Reprinted with permission from Zins JE. Aesthetic surgery of the aging face and neck. In: Siemionow M, Eisenmann-Klein M, eds. Plastic and Reconstructive Surgery Series. Berlin: Springer; 2009:Figure 26.4.)

Figure 3

(A and B) Left frontotemporal defect in 48-year-old woman caused by removal of infected bone flap 2 years earlier. Frontal and three-quarter views shown before surgery. (C and D) Frontal and three-quarter views 6 months after reconstruction of full-thickness defect with hydroxyapatite bone paste (Bone Source). (Reprinted with permission from Zins JE, et al. Contour alteration of the facial skeleton. In: Achauer BM, Guyuron B, eds. Plastic Surgery: Indications, Operatons, Outcomes. Philadelphia: Elsevier; 2000:2829. Copyright Elsevier 2000.)

Figure 4

(A) Preoperative view of a 54-year old man who underwent surgery for brain tumor removal and immediate reconstruction with calcium-based bone cement elsewhere. The cement became exposed, and two attempts to close the area using local flaps were performed. The patient was then referred to us for free flap coverage. (B, C, and D) The patient underwent reoperation, and all calcium-based bone cement plus the titanium mesh used for reconstruction was removed. Part of the dura had to be excised because it was attached to the calcium-based bone cement. A dural patch was used for reconstruction. Calcium-based bone cement was used to reconstruct a 132-cm² cranial defect 21 months later. (E) Postoperative view. Unfortunately, this patient underwent a fifth operation and the calcium-based bone cement was once again removed 2 years later because of infection and wound breakdown. (Reprinted with permission from Zins JE, Moreira-Gonzalez A, Papay FA. Use of calcium-based bone cements in the repair of large, full-thickness cranial defects: a caution. Plast Reconstr Surg 2007;120(5):1332–1342.)