An experimental model for the study of craniofacial deformities

Abstract

Purpose:To develop an experimental surgical model in rats for the study of craniofacial abnormalities. Methods: Full thickness calvarial defects with 10x10-mm and 5x8-mm dimensions were created in 40 male NIS Wistar rats, body weight ranging from 320 to 420 g. The animals were equally divided into two groups. The periosteum was removed and dura mater was left intact. Animals were killed at 8 and 16 weeks postoperatively and cranial tissue samples were taken from the defects for histological analysis. Results: Cranial defects remained open even after 16 weeks postoperatively. Conclusion: The experimental model with 5x8-mm defects in the parietal region with the removal of the periosteum and maintenance of the integrity of the dura mater are critical and might be used for the study of cranial bone defects in craniofacial abnormalities. Key words: Bone Regeneration. Craniofacial Abnormalities. Parietal Bone. Rats. RESUMOObjetivo: Desenvolver um modelo experimental em ratos para o estudo de deformidades craniofaciais. Métodos: Foram realizados defeitos ósseos de espessura total com diâmetro de 5 x 8 mm e 10 x 10mm na calota craniana em 40 ratos, machos, NIS Wistar, com peso de 320 a 420 g divididos igualmente em dois grupos. O periósteo foi retirado e a dura-máter mantida intacta. Os animais foram sacrificados na 8ª e 16ª semana de pós-operatório e amostras de tecido ósseo foram extraídas para realização da análise histológica. Resultados: Os defeitos cranianos permaneceram abertos mesmo após 16 semanas após a cirurgia. Conclusão: O modelo experimental com defeitos de 5x8mm na região parietal, com remoção do periósteo e manutenção da integridade da dura-máter são considerados críticos, e poderá ser utilizado para o estudo dos defeitos ósseos cranianos nas anomalias craniofaciais.

Effect of sustained PDGF nonviral gene delivery on repair of tooth-supporting bone defects

“…Finally, this model system, compared with the calvarial model, may be a more representative physiologic environment for evaluation of bone healing. In contrast to the previous calvarial model, which was a critical sized defect (CSD), the periodontal fenestration defect is a kinetic defect 44 , 45 . This mandibular defect provides physiologic biomechanical loading forces 46 .…”

Hybrid composites of mesenchymal stem cell sheets, hydroxyapatite, and platelet-rich fibrin granules for bone regeneration in a rabbit calvarial critical-size defect model

“…It has previously been suggested that calvaria is an anatomic area of limited mechanical stress and relative stability of the surrounding structures, and so is an ideal candidate for the study of interactions between new bone constructs and in situ bone (67). Furthermore, the patterns of bone accretion and overall bone mass in rabbits during skeletal maturation are similar to those in humans (68).…”

Sodium-DNA for Bone Tissue Regeneration: An Experimental Study in Rat Calvaria

“…The dura mater was preserved. This experimental surgical protocol represented a critical size defect, resulting in no spontaneous closure of the bone defect, not even reaching 50% of the area after 16 weeks of observation [ 39 ]. In order to minimize the number of animals used for this study, right and left osteotomy were made according to the experimental design.…”