Comparison of titanium and cobalt-chromium removable partial denture clasps

Retentive forces and fatigue resistance of thermoplastic resin clasps

“…Any excess torquing may affect the outcome of clasps negatively [6]. The increase of retention force observed in the first period of simulating could be explained by the wear between the crown and the inner surface of the clasp, which might have induced an increase in roughness of these two components during the first period of cycling, after that, the increased wear, caused a decrease in retention.…”

“…Rodriguez et al indicated an increase in retentive force during the simulation test [49], while retention decrease was reported by Bridgeman et al [6] and Kim et al [33].…”

“…In previous similar studies [6,27,33], simulating test has been performed on a masticatory simulator, and clasp retention has been measured every cycling sequence using another machine (tensile testing machine). To get the clasp on the two machines every time in the exact same position is very difficult, this could produce greater load on the abutments and lead to retention loss in a short time.…”

“…While in previous studies [6,33,49], clasp retentive forces were measured and cyclic fatigue tests were performed on a single abutment tooth.…”

Titanium removable denture based on a one-metal rehabilitation concept

“…Of the laboratory problems, casting [10][11][12][13][14][15] , cutting 16,17) , grinding 18,19) , and polishing are not easy 20) , and casting apparatus for titanium is more expensive than for the conventional dental alloys. The debonding of the denture base resin from the titanium framework [21][22][23] , deformation of the titanium clasp [24][25][26][27][28][29][30] , discoloration of the titanium surface 31) , severe wear of titanium teeth [32][33][34][35][36] , and much plaque accumulation [37][38][39] are some of the clinical problems frequently observed in our clinical practice, whereas catastrophic failures have never been found 6) . Some of these laboratory and clinical problems have been resolved by basic studies and the efforts of laboratory technicians so that cast titanium frameworks for RPDs could be constantly fabricated with clinical success [40][41][42][43] .…”