From a surgery perspective, once the nose is unblocked and obstruction relieved in the soft palate/retrolingual space area, that's enough. Barring of course bariatric surgery for weight loss, and tracheostomy as a final solution for severe sleep apnoea. The next stage is to have a mandibular advancement device fitted. This is like a tooth guard but for both upper and lower teeth. If they are made well they are fairly easy to tolerate. Avoid cheap boil in the bag type devices as they are too bulky and can damage the teeth and jaw joint. These devices work by pulling the lower jaw forward, which pulls the tongue forward and opens up the retrolingual space, again!