Effect of Implant Diameter on Fatigue Strength.
OBJECTIVE
To investigate the effect of implant diameter on fatigue strength using static and cyclic load test.


METHODS
Four different implant systems-SuperLine (Φ4.0), NRLine (Φ3.1), SlimLine (Φ2.8, Φ2.3), and (Dentium)-were grouped by implant diameter. A static load test was conducted with 5 specimens for each group using a universal testing machine to measure the ultimate failure load (UFL). With 80% of the UFL in the weakest group, the starting load for a cyclic load test was determined and the test was performed with 8 specimens for each group. All tests were conducted according to ISO14801 (2007) until implant failure occurred. After dynamically loaded, each specimen was sectioned and stereo-microscopically examined. The failure modes of each implant system were classified. Static and cyclic load test data were respectively analyzed after the test of normality, with the level of significance at P = 0.05.


RESULTS
In the static load test, the higher maximum load of the standard-diameter implant was significant compared with the recorded narrow or mini-implants (P < 0.05). The yield strengths of the Φ2.8 and Φ3.1 implants were significantly greater than that of the Φ2.3 implant (P < 0.05). In a cyclic load test, the mean number of cycles until implant failure occurred was recorded for each specimen. The value for the Φ4.0 implant was significantly greater (P < 0.001).


CONCLUSIONS
Implant diameter has an effect on the ability to withstand both static and cyclic loads within Dentium implant systems, The UFLs and fatigue cycles decreased as the implants diameter became smaller.
*Bachelor of Health Science, Department of Dental Laboratory Science and Engineering, Korea University, Seoul, Republic of Korea; Institute for Clinical Dental Research, Korea University Medical Center, Seoul, Republic of Korea. †Clinical Professor, Department of Advanced Prosthodontics, Institute for Clinical Dental Research, Korea University Guro Hospital, Seoul, Republic of Korea; Doctor of Dental Medicine, Kyung Hee University, Seoul, Republic of Korea. ‡Professor, Department of Advanced Prosthodontics, Institute for Clinical Dental Research, Korea University Guro Hospital, Seoul, Republic of Korea; Doctor of Medicine, Korea University, Seoul, Republic of Korea.
So-Yeon
SY
Song
Jeong-Yol
JY
Lee
Sang-Wan
SW
Shin
D015921:Dental Implants / Q000009:adverse effects / Q000592:standards; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis / Q000379:methods; D006801:Humans; D016474:Weight-Bearing
D015921:Dental Implants