OBJECTIVE AND IMPORTANCE: Hydroxyapatite cement, a new biomaterial tha
t is being marketed as a method for reconstructing cranial defects, of
fers many advantages. We document, herein, the complete dissolution an
d failure of this material to set in a surgically dry field, under opt
imal conditions, an occurrence that has not been previously reported.
CLINICAL PRESENTATION: Hydroxyapatite cement was used for reconstructi
on of a frontal bone defect secondary to a traumatic depressed cranial
fracture in a 9-year-old male patient. At the time of suture removal
on postoperative Day 6, we observed serous discharge from the wound, a
reappearance of the cranial defect, and brain pulsations visible subc
utaneously. INTERVENTION: The patient was returned to the operating ro
om, at which time we learned that the hydroxyapatite cement had migrat
ed out of the defect; small concretions of the cement were scattered t
hroughout the subgaleal space. The concretions of cement in the subgal
eal space and the small amount of cement remaining in the defect were
removed, and titanium mesh was used. An excellent cosmetic result was
achieved. CONCLUSION: Although offering many advantages, hydroxyapatit
e cement does carry a risk of failure to set, despite optimal techniqu
e. Causes for failure to set, as well as possible modifications in the
use of material and technique, are discussed.