Thank you! So when will you choose the flexible material? As you said, it is likely that the flexible material only has an advantage on comfort. More difficult to repair and less durable
Correct..... I use when whiny patient "doesn't want metal showing". But I only make if it meets criteria. Most manufacturers have indications for design.... For example I don't know of any thermoplastic that is recommended for bilateral distal extension rpds.
A successful flexible case has a minimal of three retentive teeth. Should not be used in a close bite case, especially a nylon type. Also not indicated for single isolated anterior teeth.
Thermoplastics are not a blanket replacement for acrylic or metal. Patients and clients always point at the flexible clasps (metal free),but the biggest benefit of a flexible rpd is the flexible major connector.
Flexibles usually fail because they are forced in non applicable cases, or processed by an experienced technician.
So the problem with your original post is it is an acetal frame, which will become brittle as it ages. It will be unrepairable as acetal does not bond to itself as a nylon based thermoplastic. Acrylic will not bond to it so eventually the retentive saddles will tear the mesh off with it. And then will become a remake.
Other thermoplastics would be a better choice. And I would try to avoid a two-part hybrid.
The reason for that advertisement, is acetal is a millable thermoplastic. It looks good in the picture, is metal free, makes you think futuristic aesthetics, and gives the guy with a mill something else to do with downtime cutting crowns. I don't use acetal in my injections. It does have its place, but it's further down the list.
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