[Effects of zygomatic arch resection in rat]

Eighty-two-day-old male Wistar rats were selected to study the pattern of craniofacial growth following partial or total resection of zygomatic arches. Rats were divided into five groups: Group I or control group; group II, with unilateral partial resection of zygomatic arch; group III, with bilateral partial resection; group IV, with unilateral total resection, and group V, with bilateral total resection of zygomatic arch. Direct dry skull and cephalometric measurements showed increased facial projection and decreased transverse facial width on side of resected arch. Different considered points, measured distances, and average results obtained are presented. Conclusions of this study are discussed emphasizing the function of zygomatic arch as moderator of morphologic development and growth of the face. Practical application of this study if results are extrapolated to growth pattern of patients with malformations of zygomatic arch, such as Treacher Collins syndrome, are discussed also, establishing as priority in their treatment the reconstruction of this structure.