Inclusion Criteria  At least 18 years old (adults & seniors, male & female). Presence of snoring, mouth-breathing or previously diagnosed with obstructive sleep apnea. If present, stable cardiopulmonary disease (heart failure, chronic obstructive pulmonary disease, ventricular dysrhythmia), morbid obesity or other serious health conditions, must be under a physician's care; participant must obtain written permission from the physician to participate in this study. If participated in recent OA clinical trial at the Texas A&M University College of Dentistry (IRB# 2017-0390) must be willing to try the myTAP as alternative to OA that is currently being used. The myTAP is a chairside-fitted OA that may be more comfortable and effective than the previous OAs and includes a mouth-shield. At least 8 teeth per arch to support OA device. Mallampati score from I to III; palatine tonsils grade 0,1 or 2. Willing & able to provide verbal & written informed consent in English & understand how to apply, remove & utilize the sleep recorder & the OA device, as well as fill out brief questionnaires & nightly sleep diary.  Exclusion Criteria:  Unable or unwilling to complete the study demands & schedule. Active temporomandibular joint dysfunction (TMD) or jaw muscle pain, morphological airway abnormalities. Severe restrictions in jaw opening. Pre-existing difficulty swallowing; throat or neck related health issues; unmanaged endocrine dysfunction. Severe chronic nasal obstruction that precludes possibility of nasal breathing. Severe psychiatric & neurological disorders; intellectually disabled. Advanced periodontal disease (e.g., loose teeth). History of uvulopalatopharyngoplasty (UPPP) surgery. Loose teeth, loose crowns or fillings. Removable dentures or bridges. Temporary crowns. Orthodontic braces. Other oral conditions which would be adversely affected by wearing dental appliances.