Experimental facial augmentation with hydroxyapatite cement

Feasibility of demineralized bone matrix for craniomaxillofacial contour restoration

Demineralized bone matrix (DBM) could be a good alternative for craniomaxillofacial contour restoration, especially in perialar, malar, temporal, and frontal regions. In this study, the histologic behavior of DBM was investigated in different tissue planes to determine its proper application plane for restoration of craniomaxillofacial contour deformities and defects.Forty Wistar rats were divided into 6 groups: (1) 0.3 mL of 0.9% saline was injected into the subperiosteal plane of the cranium, (2) 0.3 mL of DBM was implanted into the subperiosteal plane of the cranium, (3) 0.3 mL of 0.9% saline was injected into the subdermal plane on the left inguinal region, (4) 0.3 mL of DBM was implanted into the subdermal plane on the right inguinal region, (5) 0.3 mL of 0.9% saline was injected between the left external and internal oblique muscles, and (6) 0.3 mL of DBM was implanted between the right external and internal oblique muscles. At the 8th week half of the rats and at 16th week the remaining rats were killed in each group, and tissue samples were harvested. Histological and immunohistochemical evaluation revealed new bone tissue and bone marrow formation in all planes that DBM was given.Demineralized bone matrix can provide satisfactory results in craniomaxillofacial contour deformities including forehead, temporal, and malar augmentations, as well as mental and perialar augmentations and saddle nose corrections, with supraperiosteal or deep subcutaneous applications. However, superficial applications must be avoided because of the possibility of palpation, because it induces hard bone tissue formation in all tissue planes.

Complications of hydroxyapatite bone cement in secondary pediatric craniofacial reconstruction

Hydroxyapatite cement has become a popular alternative to bone grafts in reconstructing the calvarium. Although animal studies have shown promising results with use of hydroxyapatite, human clinical studies have shown mixed results including significant rates of infection. This is a retrospective chart review during a 7-year period (1997-2003) of 20 patients who underwent secondary forehead cranioplasty with hydroxyapatite cement (Norian Craniofacial Reconstruction System). Basic demographics including age, sex, and diagnosis were identified. Characteristics of the defects were recorded including size, location, and depth (full versus partial thickness). The volume of hydroxyapatite and any adjunctive procedures were identified. The postoperative course was analyzed for length of follow-up and the presence of infections.Twenty patients were identified in which Norian had been used and 3 patients were lost to follow-up. Secondary forehead asymmetry was the most common presentation. The mean volume of hydroxyapatite used was 24.4 mL. All patients had initially acceptable aesthetic results. Of the 17 patients, 10 (59%) ultimately had infectious complications. Infection occurred on a mean of 17.3 months after surgery (range, 4 mo to 4 y), and the mean amount of hydroxyapatite used was 32.5 mL (infections) versus 14.3 mL (no infections). Of the 10 patients with complications, 9 required surgical debridement and subsequent delayed reconstruction. Although hydroxyapatite cement can yield excellent aesthetic results, its use in secondary reconstruction has yielded unacceptably high infection rates leading to discontinuation of its use in this patient population.

Calcium Hydroxylapatite for Facial Rejuvenation

Porous calcium hydroxylapatite has been used in otolaryngology, dentistry and radiology for many years. Currently, calcium hydroxylapatite is gaining popularity for facial esthetics in the form of the product Radiesse (San Mateo, CA). Although Radiesse is not yet approved in the United States for cosmetic use, it is being used off-label by an increasing number of dermatologists and plastic surgeons for facial soft-tissue augmentation. Preliminary clinical and histologic studies have shown safety, efficacy and durability in various esthetic applications including the nasolabial folds and HIV lipoatrophy.