Systems and methods are provided for optimizing the treatment of obstructive sleep apnea (OSA) using an oral appliance. The oral appliance can be configured by non-dental staff to safely conform to the dentition of a patient. The appliance includes configurable trays that include retention material that conforms to the dentition of the patient. The position of the upper and lower trays relative to one another can be adjusted both horizontally and vertically. The position of the upper and lower trays can be locked into place to maintain the position of the trays at a preferred treatment position. Methods for creating an appliance customized for a patient are also provided. Methods for using the customized appliance in combination with sleep study data is also provide. Methods for using the customized appliance to with pre-operative assessments and sleep study data to predict and reduce the risk of perioperative complications are also provided.