Consequences on the growth of maxilla and mandible of surgical bone defect on mandibular ramus of rats

Lucimar Rodrigues Luciane Toshie Miyazaki João Gualberto de Cerqueira Luz About the authors

PURPOSE: To analyse the consequences on the growth of maxilla and mandible of a surgical bone defect that simulates a mandibular ramus fracture. METHODS: A group of 25 one-month-old Wistar rats were used in this study. Under general anesthesia, and through a submandibular incision, a vertical osteotomy on the right side of the mandibular ramus was made using a surgical drill. The animals were sacrificed after two months, soft tissues removed, and the mandible disarticulated. The skull was submitted to axial radiograph and the hemimandibles to a lateral radiograph. With these, cephalometric mensurations were made through a computer system, and the obtained values submitted to Student's t-test. RESULTS: The height of the mandibular ramus presented significant difference (p=0,010) as well as the length of mandible, both to the condyle (P=0,015) and the angle (p=0,001). There was no significant difference to the mensurations of the maxilla. CONCLUSION: The consequences of the experimental surgical bone defect on the mandibular ramus in the growing period were the lessening of the mandibular height and length.

Mandible; Fracture mandibular; Maxillofacial development

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