Mechanical Strength of Implant Body Related to Improper Occlusal Load and Embedded Depth

Mechanical Strength of Implant Body Related to Improper Occlusal Load and Embedded Depth
26 June 2003
F. WATANABE1, S. KOMASTU, and Y. HATA, 1 Nippon Dental University, Niigata, Japan
IADR
Objectives:Although implant body is rarely fractured in clinical usage, if it has occurred it would be more harmful to the patient. The largest cause of implant fracture may be considered improper occlusal load deviated from an axis of an implant. The purpose of this study is to investigate the mechanism of the fracture of implant body. Twenty-four IMZ Twin Plus Implants (with twelve for 3.3mm of diameter, 10mm of length and with twelve for 4mm of diameter , 11mm of length : Friadent Co., Germany) were used for this study. Methods: Six simulated implant embedding models were made: two kind of diameter( 3.3 and 4.0mm) implants were embedded with 3 levels (5, 7, 11mm in depth). First premolar cast crowns were fabricated with palladium alloy and cemented for each implant abutment with 30kg loading. The specimen was fixed on Servopulser (EHF-FB: Shimadzu, Japan) and pulsating load of 60 kg was applied 60 times per minutes to the occlusal area in the direction of 0-degree and 45-degree angle to an implant axis till the breaking or bending point of implant body. Results:Zero-degree angle models were not fractured at the pulsating load up to 100,000 times regardless of embedded depth. 45 degree loading was caused fractures or bended between 20 and 50 times pulsating loading.Conclusions: The fracture or bending point of shallower embedded implant was higher than deeper embedded one.