Osteogenesis in Calvarial Defects: Contribution of the Dura, the Pericranium, and the Surrounding Bone in Adult versus Infant Animals

Abstract

Guided bone regeneration is a promising means for reconstructing bone defects in the cranium. The present study was performed to better define those factors that affect osteogenesis in the cranium. The authors studied a single animal model, investigating the contribution of the dura, the pericranium, and the adjacent calvarial bone in the process of calvarial regeneration in both mature and immature animals. Bilateral, 100-mm2, parietal calvariectomies were performed in immature (n = 16) and mature (n = 16) rabbits. Parietal defects were randomized to one of four groups depending on the differential blockade of the dura and/or the pericranium by expanded polytetrafluoroethylene membranes. Animals were humanely killed after 12 weeks, and histometric analysis was performed to quantitate the area of the original bone defect, new bone formation, and new bone density. Bone formation was quantified separately both at the periphery and in the center of the defects. Extrasite bone formation was also quantified both on the dural and on the pericranial sides of the barriers. Bone regeneration was incomplete in all groups over the 12-week study period, indicating that complete bone healing was not observed in any group. The dura was more osteogenic than the pericranium in mature and immature animals, as there was significantly more extrasite bone formed on the dural side in the double expanded polytetrafluoroethylene barrier groups. In both the dural and the double expanded polytetrafluoroethylene barrier groups, dural bone production was significantly greater in immature compared with mature animals. The dura appeared to be the source of central new bone, because dural blockade in the dural and double expanded polytetrafluoroethylene groups resulted in a significant decrease in central bone density in both mature and immature animals. Paradoxically, isolation of the pericranium in mature animals resulted in a significant reduction in total new bone area, whereas pericranial contact appeared to enhance peripheral new bone formation, with the control group having the greatest total new bone area. The present study establishes a model to quantitatively study the process of bone regeneration in calvarial defects and highlights differences in the contribution of the dura and pericranium to calvarial bone regeneration between infant and adult animals. On the basis of these findings, the authors propose that subsequent studies in which permeability of the expanded polytetrafluoroethylene membranes is altered to permit migration of osteoinductive proteins into the defect while blocking prolapse of adjacent soft tissues may help to make guided bone regeneration a realistic alternative for the repair of cranial defects.

Spring-mediated skull expansion: overall effects in sutural and parasutural areas. An experimental study in rabbits

“…We agree with the hypothesis that a smaller detachment of the dura mater may be associated to this finding 18 , which is clearly evidenced by Gosain 19 who also observed that the defect created in adult animals was maximized by the maintenance of contact with the pericranium (bone growth from peripheral areas) and dural contact (bone growth from the central area). A similar finding was observed in Group III and IV slides ( Figure 4).…”

Biomimetic Engineering of Nanofibrous Gelatin Scaffolds with Noncollagenous Proteins for Enhanced Bone Regeneration

“…These three types of tissues have been reported to contain stem/progenitor cells for bone formation. 40 A significantly higher amount of bone formed in the NF-Gelatin-NCPs than in the controls after in vivo implantation for 6 weeks, which indicates that the NCPs facilitate the recruitment of host cells for tissue regeneration. The exact mechanism of the cell homing process is unknown and warrants further investigation in future studies.…”

Skull Expansion by Spring-Mediated Bone Regeneration

“…The hypothesis that a minor detachment of the dura mater may be associated with this finding is established by Mabbutt and Kokich(Mabbutt and Kokich 1979) and is clearly evidenced by Gosain et al (Gosain, Santoro et al 2002) who also observed that the defect created in adult animals was maximized by maintaining the contact with the pericranium (bone growth from peripheral areas) and dural contact (bone growth from depth). Similar finding is observed in Groups III and IV (Figure 4).…”

“…Rabbits have been widely used as experimental model in studies of behavior of cranial sutures, intracranial pressure, craniometric variations, evolution of fixation materials, and distraction of craniofacial structures (Mabbutt and Kokich 1979;Persson, Roy et al 1979;Alberius and Selvik 1983a;Alberius, Selvik et al 1986;Persing, Babler et al 1986;Alberius, Malmberg et al 1990;Smith, Mooney et al 1996;Singhal, Mooney et al 1997;Losken, Mooney et al 1998;Mooney, Siegel et al 1999;Wendy, Fellows-Mayle et al 2000;Gewalli, Guimaraes-Ferreira et al 2001;Putz, Smith et al 2001;Abreu 2002;David, Gewalli et al 2002;Gosain, Santoro et al 2002;David, Proffer et al 2004;Guimarães-Ferreira, Miguéns et al 2004;Cooper, Singhal et al 2006;Cardoso, Cançado et al 2007;Davis, Windh et al 2008;Davis, Windh et al 2009). Cerebral growth curve of rabbit specimens is similar to those of newborn human children: craniofacial growth in rabbits is accelareted immediately after birth, progressively decreasing from two to thirty-four weeks of age (Alberius, Selvik et al 1986;Abreu 2002).…”