Maxillary/ˈmæksɪleri/ Definition 1 of 3Pro Tip 1/3Upper Jaw Related Focus on issues or structures located in the upper jaw region. A maxillary expansion device helps to widen the upper jaw. Pro Tip 2/3Dental Context Often used by dentists or oral surgeons when discussing treatment. Maxillary alignment will be corrected with braces. Pro Tip 3/3Healthcare Specific Commonly associated with the medical field and professional healthcare terminology. The maxillary sinus infection requires antibiotic treatment.