An oral device for treating obstructive sleep apnea is generally described. In an embodiment, the oral device includes an anchoring member, a lip sealing member and an air transmission member configured to receive and transmit air to a user. The air transmission member may divide and distribute the air to multiple locations within the user's oral cavity. The anchoring member is configured to receive a dentition of the user. According to some embodiments, the lip sealing member may include an inner lip seal and an outer lip seal. The inner and outer lip seals are customized to the user's lips and may be slidably received on the air transmission member. Thus, the lip sealing member is configured to provide a substantially airtight seal for the user's lips, thereby limiting and/or inhibiting air exchange between the user's lips.
