Purpose: This descriptive analytical study evaluated the cause, type, incidence, demographic, and treatment data of zygomatico-orbital complex and zygomatic arch fractures managed at our program during a 5-year period. Patients and Methods: A total of 1,857 charts of patients presenting maxillofacial trauma and treated by the Division of Oral and Maxillofacial Surgery, from the Piracicaba Dental School (UNICAMP), were reviewed. A total of 371 patients presented with zygomatico-orbital complex and/or zygomatic arch fractures. Patients with isolated orbital fractures were excluded. The patients ranged in age from 2 to 88 years. Epidemiological data including age, gender, etiology, site of injury, and details of treatment were collected and tabulated in Excel software (Microsoft). All maxillofacial injuries were assessed and treated by residents and staff surgeons. Other concomitant bodily injuries were treated by pertinent consulting specialists. Results: The majority of fractures were Sustained by males between 21 and 40 years old, usually resulting from falls, altercations, and bicycle accidents. Unilateral fractures of zygomatico-orbital complex were present in 266 patients (71.69%). Bilateral fractures were found in 22 cases (5-93%). Unilateral zygomatic arch fractures occurred in 39 cases (10.51%). A total of 210 patients (56.60%) did not receive surgical treatment. Surgical intervention was done in 161 patients (43.40%). The surgical treatment was conducted using the approach as reported by Ellis and Kittidumkerng in 1996. A complication incidence of 6.47% was observed, which is compatible with related articles in the literature. Conclusions: The study revealed interesting features about etiology, demonstrated by the high occurrence of bicycle accidents. The treatment protocol proposed to the patients showed adequate results as evidenced by low complication frequency. The findings of this study bring information about an area in Sao Paulo State, Brazil, that is valuable in reaffirming previously established trends and identifying new patterns of disease frequency. (c) 2006 American Association of Oral and Maxillofacial Surgeons.6416367