ISO 14801 Dynamic Fatigue Testing of Dental Implants

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ISO 14801 is an industry standard test method that regulatory agencies use to establish minimum performance standards for dental implants.

What Is ISO 14801?

Dental implants have become a popular, permanent replacement for missing teeth. They are inserted into the jawbone and, over time, fuse with the bone. Dental implants will sometimes experience rare mechanical failures such as fractures. Most of the time, these are caused by time-dependent metal fatigue. ISO standards ensure the longevity of the implant.

The implant is tested under what is deemed to be the worst case conditions experienced by the implant. Those conditions include tilting the implant by a certain angle, usually 30°, with respect to its longitudinal axis, in order to induce bending stresses representative of the implant’s inclination in the oral cavity. Moreover, part of the thread may be left outside of the basal grip to mimic bone loss, therefore adding an additional lever that increases the total bending moment.

What Other Resources Focus on Dental Fatigue Applications?

Important Considerations When Testing per ISO 14801

Caution shall be taken when using the results for design as they are generally not indicative of the true fatigue properties of the material in this application. ISO 14801 tests do not represent true worst case applications. Researchers report multiple scenarios that support the need for higher test loads and random spectrum loading conditions at speeds to 3 Hz. ISO 14801 is designed to validate and to compare how implants perform relative to each other.

ISO 14801 Test Method

First, a shear failure test is performed to establish maximum static load.That establishes the baseline fatigue test requirement. Each test specimen is cyclically loaded at a 30° angle from the longitudinal axis. Loading is sinusoidal at a frequency of 15 Hz or less (≤ 15 Hz). The test goal is to determine the endurance or fatigue properties of endosseous dental implants when subjected to dynamic loading. Tests are carried out from 2 to 15Hz and impart a bending fatigue onto the implant after potting or insertion into an appropriate test sample holder.

Test multiple samples to generate S-N endurance curves. Runout can vary depending on the frequency of the test, and range from 2,000,000 (2 Hz) to 5,000,000 (15 Hz) cycles. Testing in saline or a constant fluid temperature bath of 37°C (98.6°F) is desired in addition to ambient testing of 20°C (68°F). When testing in a bath, the maximum frequency is 2 Hz.

Test data requirements include capturing loads applied, number of cycles performed (duration), and loading frequency.

Dynamic Test Machines for ISO 14801

Our 800 series of fatigue test machines are ideal for these dental implant fatigue test applications. 

The lower priced 840E2 test machines are capable of performing fatigue tests at speeds up to 15 Hz with load capacities of 500 N (112 lbf) and up. The 840 load frame does not accommodate the bath nor the adjustable angle base. Both product families feature servo controlled electric dynamic actuators. They both are capable of precisely controlled loading and fatigue reliability. They both meet the requirements of the standard. 

Test Fixtures for ISO 14801

GISO14801: A 30° angled base into which the dental implant is screwed. A flat bottom compression probe that is attached to the actuator rod and pushes down onto the implant. An optional probe includes a U-joint distal end which avoids transverse motion at the interface with the hemispherical fixture as required in the standard. .

GISO14801XY: Provides mechanical flexibility such as an adjustable test sample angle with linear slides to allow the sample position to be adjusted in either X or Y dimension. These features are useful when performing research and development of new implants.

Biobath: Saline bath at 37°C