SAE, I see that you asked about sjogren's & dentures months ago, so I hope that you check back here again. My dad had dealth with this disease for years and also has gone through several sets of dentures. About 4 years ago he had the really neat and very expensive implants done and has been very pleased with the results.
He still pops his top tray in and out when he's not eating (we joke about finding them in the console of the car or on the recliner side table---yuck yuck !!!), but he says with his mouth staying so dry that "it just feels better" to take them out most of the time. He always has a bottle of water on hand along with that Biotene mouthwash and a tube of the Biotene mouth gel moisturizer, and I think that helps alot. One thing for sure...he won't ever be dehydrated !
But as for the implants....he says it has made the denture wearing much easier having to deal with the Sjogren's Disease.
Hope this helps. Oh...just make sure you have an excellent oral surgeon who is familiar with the disease.