Prostheses made of acetal resin or nylon (polyamide), commonly known as “hookless” or “clear/flexible” dentures, are highly sought after by patients because they eliminate the unsightly aesthetic appearance of metal hooks; their hooks are tooth-colored or pink. However, these prostheses have very serious disadvantages in terms of periodontal and bone health. Traditional metal-hooked prostheses are rigid and transfer part of the chewing force to the tooth through metal clasps that sit on the abutment teeth. Flexible prostheses, on the other hand, bend at the base when chewing force is applied, uncontrollably pressing all that enormous load directly onto the thin gum line and bone around the abutment teeth. This causes the gums to quickly recede from the tooth, gum recession, and much more aggressive and rapid bone resorption of the bone tissue under the prosthesis’s pressure.
