Wear abrasion testing methodology for denture teeth

Objectives: To observe the wear of commercial available denture teeth using mouth motion simulator.

Methods: Four groups of 15 samples each of denture teeth were tested in this study. Prefabricated anterior denture teeth were embedded into composite with 9mm by diameter SEM stud. The flat surface of prefabricated tooth was obtained by grinding it up to 1200-grit silicon carbide paper. All samples were thermo-cycled for 5,000 cycles prior to testing. Samples were Hertzian contact loaded (4.75 mm diameter Al₂O₃-ball) using a mouth motion simulator (SD Mechatronik, Germany) with lift off from the specimen and 0.8 mm horizontal movement under 50N load inside a water chamber. Five samples were removed from each group at 50k, 100k and 200K chewing cycles and the depth and total volume lost were measure with 3D optical laser profilometers (UBM Corporation).

Statistically analysis was accomplished with two-way ANOVA. Significance was predetermined at p<.05.

Results: At 50K chewing cycles, group 1 showed the greatest mean of wear followed by group 4, 2 and 3, respectively. This pattern held for 100K chewing cycles but change slightly at 200K with Group 4 showed the greatest mean of wear followed by group1, 2, and 3.

 

	Chewing cycles
	50,000		100,000		200,000
	Max Depth (um±SD)	Vol Loss (mm3±SD)	Max Depth (um±SD)	Vol Loss (mm3±SD)	Max Depth (um±SD)	Vol Loss (mm3±SD)
Group1 Potrait IPN (Dentsply)	52.68±16.99a	0.027±0.014a	69.68±18.07a	0.044+0.019a	90.67±18.98a	0.071+0.026a
Group2 Vita MFT (Vita Company)	31.05±3.69b	0.009±0.002b	53.46±6.41b	0.026+0.006b	85.07±8.34b	0.064+0.011b
Group3 Mondial 6i (Heraus)	24.13±4.07c	0.007+0.001c	42.85±6.44c	0.016+0.004c	68.51±11.46c	0.04+0.009c
Group4 Physiostar NFC (Condular USA)	39.04±3.16d	0.016+0.002d	62.63±4.81d	0.037+0.006d	98.13±8.61d	0.087+0.015d

Conclusions: Group 3 yield higher wear resistance in lower and higher chewing cycles compared with the other groups (P<0.001).