RESUMO
Autologous dentin is frequently used in guided bone regeneration due to its osteoinductive properties, which come from its similarity to native bone. On the other hand, the xenogeneic bone biomaterial Cerabone® serves as a biocompatible, but hardly resorbed biomaterial. During bone healing, an inflammatory, vascular, and osteogenic response occurs in which cytokines such as tumor necrosis factor-alpha (TNF-α), vascular endothelial growth factor (VEGF), and osteopontin (OPN) are released locally and systemically. The aim was to follow up the dynamics (on days 3, 7, 15, 21, and 30) of critical-sized bone defect (CSBD) healing after the implantation of bovine devitalized dentin, rat dentin, and xenogeneic bone biomaterial. For this purpose, histological and histomorphometric methods were employed. Additionally, serum concentrations of TNF-α, VEGF, and OPN were monitored in parallel to better understand the biomaterial-dependent systemic response in rats. At the last time interval, the results showed that the bone defect was bridged over in all three groups of biomaterials. The rat dentin group had the highest percentage of bone volume (BV/TV) and the least percentage of residual biomaterial (RB), which makes it the most optimal biomaterial for bone regeneration. Serum concentrations of the TNF-α, VEGF, and OPN refer to systemic response, which could be linked to intense bone remodeling between days 15 and 21 of the bone healing.
RESUMO
A 66-year-old male patient was admitted due to high fever, severe headaches and disturbance of consciousness. Meningitis was confirmed by lumbar puncture and intravenous antimicrobial therapy was started. Since he had undergone radical tympanomastoidectomy 15 years before, otogenic meningitis was suspected, so the patient was referred to our department. Clinically, the patient manifested watery discharge from the right nostril. Microbiological analysis verified Staphylococcus aureus in a cerebrospinal fluid (CSF) sample acquired by lumbar puncture. Radiological work-up, including computed tomography and magnetic resonance imaging scans, showed an expanding lesion of the petrous apex of the right temporal bone disrupting the posterior bony wall of the right sphenoid sinus with radiological characteristics indicating cholesteatoma. Those findings confirmed rhinogenic meningitis caused by expansion of the petrous apex congenital cholesteatoma into the sphenoid sinus, allowing nasal bacteria to enter the cranial cavity. The cholesteatoma was removed completely by the simultaneous transotic and transsphenoidal approach. Since the right labyrinth was already non-functional, there was no surgical morbidity after labyrinthectomy. The facial nerve remained preserved and intact. The transsphenoidal approach enabled removal of the sphenoid portion of the cholesteatoma and two surgeons met together at the level of the retrocarotid segment of the cholesteatoma, completely removing the lesion. This case represents an extremely rare condition in which a petrous apex congenital cholesteatoma expanded through the petrous apex to the sphenoid sinus, causing CSF rhinorrhea and rhinogenic meningitis. According to available literature, this is the first case of petrous apex congenital cholesteatoma causing rhinogenic meningitis successfully treated with the simultaneous transotic and transsphenoidal approach.
