Relation between Viscosity and Film Thickness of Dental Luting Cements

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 45; no. 5; pp. 612 - 621
• Main Authors: Kimura, Kohei, Kasahara, Shin, Hosotani, Makoto, Ando, Masaaki, Saito, Hirota, Hatakeyama, Noriko
• Format: Journal Article
• Language: Japanese
• Published: Japan Prosthodontic Society 2001
• Subjects: cement; film thickness; particle size distribution; powder; viscosity
• ISSN: 0389-5386; 1883-177X
• DOI: 10.2186/jjps.45.612

Purpose: Film thickness of dental luting cement is an important property that influences in success of fixed prosthodontics. Conventionally, it has been considered that the film thickness depends on the maximum particle size of cement powder and the viscosity of cement mixtures. However, the detailed mechanism remains uncertain. This study aimed to measure basic properties, consistency, film thickness, distribution of powder particles and viscosity change after mixing, and the factors given to the film thickness were investigated. Methods: Four commercial dental luting cements were used. Basic properties were measured following the standard of JIS T-6602 (Japanese Industrial Standard, corresponding to ISO 9917: Dental Water-based cements), and in addition, cement powder distributions were measured. Apparent viscosity changes after mixing were measured by a Cone-Plate-type Rotary Viscometer, and film thickness was measured at each viscosity of cements. Results: Consistency rose with the time course, and film thickness was not always increased. No relation could be recognized between the maximum particle size of cement powder and film thickness. As a result of the measurement, the viscosity increased, when it grew on doing the film thickness. Both relations were almost rectilinear. The tendency was different according to the type of cement. Conclusions: For film thickness of the cement, an effect of particle size could not be observed. It was indicated that the viscosity change after mixing, and the particle size distribution of cement powder, influenced film thickness.