[Comparison of friction and abrasion between six different dental materials and natural enamel].
OBJECTIVE
The purpose of this study was to evaluate and compare the friction and abrasion of six kinds of dental materials that was widely used clinically. The mechanisms were investigated to provide experimental reference for selecting proper restorative material to protect opposite natural enamel of the patients.


METHODS
In the experimental groups,pure Ti, Ti alloy, Au-Pd alloy, Ni-Cr alloy, AgHg alloy,ceramic were fabricated into thirty uniform 8.0mmx8.0mmx2.0mm block. Five specimens in each group.In the control group,five recently extracted mandibular third molar of adults were fabricated into 8.0mmx8.0mmx2.0mm block. Steatites were fabricated into discs in the diameter of 25mm and thickness of 2.0mm to act as counter sample materials. The mass loss of each specimen and the opposing steatite were weighted by electric balance. The volume loss of the materials and opposing steatites were analyzed by SPSS11.5 software package and the difference was compared between each group.


RESULTS
The ranking of the volume loss of six materials and enamel from the most to the least was group A, group E, group C, group D, group B, group F and group G. Significant difference was found between group A and the other groups. No significance was found between group G and F. The coefficient of friction of group A-G was 0.68, 0.12, 0.11, 0.41, 0.38, 0.48 and 0.65,respectively.


CONCLUSIONS
The six materials in this study were less resistant to wear than natural tooth. The wear of pure Ti, AgHg alloy and Ni-Cr alloy are to enamel.
Yan
Hong-hai
HH
Department of Stomatology, The second Clinical College of Zhejiang Traditional Medical University, Hangzhou 310005, China. yhhai@hzcnc.com
Huang
Hai-rong
HR
Zhang
Zhuo-ming
ZM
Yang
Jin-lin
JL
D003743:Dental Enamel; D003764:Dental Materials; D003776:Dental Porcelain; D019554:Dental Restoration Wear; D017276:Friction; D008422:Materials Testing; D013499:Surface Properties
D003764:Dental Materials; D003776:Dental Porcelain