What joylondon said is mostly true in my case. An obturator aids in speaking and swallowing. You can still speak and swallow, but without a hard palate or with a partial hard palate speech has a nasal quality to it, swallowing liquids can leak into the nose since there is an open or partial opening into the nose/ nasal cavity. An obturator has an artificial hard palate can contain the missing teeth and maxilla.( jaw)Breathing is NOT changed or affected with one. You asked about quality of life. Thats a hard question because people define QOL differently. Yes, my life has changed. I had radiation after surgery and i think that decision created the most problems. Although i followed the correct instruction i still developed trismus and the cancer returned later in my neck. ( neck) dissection)So radiation was considered a failure. I now suffer from fibrosis, pain and stiffness in my neck much worse then what my doctors told me. Would i have radiation again knowing what i do now? No. I think quality of life is what you make it. I cannot eat normally, talk normally without my obturator, always carry water with me for dry mouth, pain meds for neck and jaw pain,, hearing loss from radiation,,requiring hearing aids, etc. that has been 3 hears ago but my life is filled with joy. I am alive and have adjusted to my new normal. I think it is important that you have on your team a qualified surgeon oncologist speech therapist, radiation oncologist, and physical therapist. Its a plus to have a cancer rehab program specialized in head and neck cancer in your area. Therapies should start immediately after surgery and THROUGHOUT your recovery and for years after if needed. Oh yes, a prosthodontist or maxillofacial,specialist with knowledge and experience with an obturator is essential. In my opinion, general dentists do not have the training to manage your prosthesis.