Effect of Dental Implant Diameter on Fatigue Performance. Part I: Mechanical Behavior

Abstract

The results of this study emphasize the importance of implant diameter on fatigue behavior. Narrow implants failed to show typical fatigue behavior which might be attributed to the implant design.

On the mechanical integrity of retrieved dental implants

“…In that context, one should note, that a higher incidence of implant fracture has been reported in narrow implants. 25 The current results do not confirm those observations when the two implant materials are considered together, but it must be kept in mind that each implant has its own mechanical history, as opposed to carefully controlled fatigue testing, as e.g in 17 .…”

“…The effect of implant diameter was previously studied "in-vitro", 17 where narrow implants exhibited a lower fatigue strength and earlier failure. In that context, one should note, that a higher incidence of implant fracture has been reported in narrow implants.…”

“…8,[15][16] The cause(s) for fatigue crack initiation was first shown to be related to implant design that includes significant stress concentrators. 15,[17][18] Accelerated fatigue failure was also observed for implants that were ϳ cyclically loaded in a saliva-like environment, 19 indicating the potentially adverse effects of the in-vitro atmosphere. Moreover, the surface roughening procedure, aimed at promoting osseointegration 20 was also evaluated as a potentially damaging factor to the mechanical performance and reliability of the implants.…”

Fatigue Failure of Narrow Implants with Different Implant‐Abutment Connection Designs

“…Considering that the varied implant‐abutment connection geometries affect the performance of standard diameter implants, it seems reasonable to hypothesize that the reduced material bulk in NDIs may proportionally hamper long‐term function, which is yet to be investigated. Their small diameter and reduced wall thickness can result in an increased bending of the prosthetic components and consequently compromise the restoration's reliability …”

Mechanical and Spectroscopic Analysis of Retrieved/Failed Dental Implants

“…Habits such as bruxism may result in an excessive overload on the implant system, making it one of the most common failures [7]. Implants with a smaller diameter are more vulnerable to fracture as compared with ones with larger diameters, in the posterior region [8]; it is important to keep in mind, however, that each dental implant used may have a mechanical history of its own as compared with implants lost as a result of controlled fatigue [9]. In addition, surface roughening procedures-which are particularly aimed at increasing osseointegration-may also contribute as a damaging factor.…”