Implant failure

Key takeaways

Implant failure belongs to biology; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Implant failure to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Implant failure from memory before moving on to harder problems.

Reference excerpt

Implant failure refers to the failure of any medical implant to meet the claims of its manufacturer or the health care provider involved in its installation. Implant failure can have any number of causes. The rates of failure vary for different implants. The monitoring of the safety of implants is conducted within the context of broader pharmacovigilance.

Common types of failure

Material degradation Implant failure can occur due to the degradation of the material an implant is made of. With time, mechanical degradation, in the form of wear or fatigue, or electrochemical degradation, in the form of corrosion, can occur. Biotoxicity, particularly in metal implants, can arise due to ion release.

Bacterial infection Implants, made of synthetic materials, are naturally coated by a biofilm by the body, which may function as a favorable medium for bacteria growth. Implant failure due to bacterial infection of the implant can occur at any point of implant lifetime. Bacteria may already reside on the implant or be introduced during the implantation. Typical failure mechanisms include tissue damage and implant detachment due to bacteria generated biofilm.

Hip replacement failure Hip replacement implants can fail. Outcomes are normally recorded in a joint replacement registry to ensure patterns are picked up upon. In 2013 Johnson & Johnson shared documents which indicated that 40% of a class of hip replacement implants which it manufactured had failed.

Pacemaker failure

Pacemaker failure is the inability of an implanted artificial pacemaker to perform its intended function of regulating the beating of the heart. It is defined by the requirement of repeat surgical pacemaker-related procedure after the initial implantation. Causes of pacemaker failure included: lead related failure (lead migration, lead fracture, ventricular perforation), unit malfunction (battery failure or component malfunction), problems at the insertion site (infections, tissue breakdown, battery pack migration), and failures related to exposure to high voltage electricity or high intensity microwaves.

Cochlear implant failure Cochlear implants are used to treat severe to profound hearing loss by electrically stimulating the hearing nerve. Clinical symptoms of cochlear implant failure include auditory symptoms (tinnitus, buzzing, roaring, popping sounds), non-auditory symptoms (pain, shocking sensation, burning sensation, facial stimulation, itching), and decrease in the patient's hearing performance. When such symptoms occur, the patient's clinical team evaluates the patient and the device using in-situ methods, and determines if revision surgery is necessary. The most commonly reported device failures are due to impacts, loss of hermeticity, and electrode lead malfunctions. Most manufacturers provide on their websites the survival rate of their marketed implants, although they are not required to do so. In order to improve and standardize failure reporting practices to the public, the AAMI is developing an American standard for cochlear implants in collaboration with the FDA, major cochlear implant manufacturers, the CALCE center for reliability, doctors, and clinicians.

Dental implant failure

Failure of a dental implant is often related to the failure of the implant to osseointegrate correctly with the bone, or vice versa. A dental implant is considered to be a failure if it is lost, mobile or shows peri-implant (around the implant) bone loss of greater than 1.0 mm in the first year and greater than 0.2 mm a year after. Dental implant failures have been studied. Persons who smoke habitually prior to having dental implants are significantly more likely to have their implants fail. Individuals who have diabetes and those who disregard general oral hygiene are also at higher risk of having their implants fail.

Responses to implant failure In 2012 Royal College of Surgeons of England and the British Orthopaedic Association called for increased regulation of implants to prevent implant failure. A 2011 study by Dr. Diana Zuckerman and Paul Brown of the National Research Center for Women and Families, and Dr. Steven Nissen of the Cleveland Clinic, published in the Archives of Internal Medicine, showed that most medical devices recalled in the last five years for "serious health problems or death" had been previously approved by the FDA using the less stringent, and cheaper, 510(k) process. In a few cases the devices had been deemed so low-risk that they did not need FDA regulation. Of the 113 devices recalled, 35 were for cardiovascular issues. This may lead to a reevaluation of FDA procedures and better oversight.

References

Further reading Groeger, Lisa (30 April 2012). "Four Medical Implants That Escaped FDA Scrutiny - ProPublica". propublica.org. Archived from the original on 4 June 2013. Retrieved 5 June 2013. Wagenberg, B.; Froum, S. J. (2006). "A retrospective study of 1925 consecutively placed immediate implants from 1988 to 2004". The International Journal of Oral & Maxillofacial Implants. 21 (1): 71–80. PMID 16519184. De Bruyn, H.; Collaert, B. (1994). "The effect of smoking on early implant failure". Clinical Oral Implants Research. 5 (4): 260–264. doi:10.1034/j.1600-0501.1994.050410.x. PMID 7640341. Tang, L.; Eaton, J. W. (1995). "Inflammatory responses to biomaterials". American Journal of Clinical Pathology. 103 (4): 466–471. doi:10.1093/ajcp/103.4.466. PMID 7726145. Papageorgiou, S. N.; Zogakis, I. P.; Papadopoulos, M. A. (2012). "Failure rates and associated risk factors of orthodontic miniscrew implants: A meta-analysis". American Journal of Orthodontics and Dentofacial Orthopedics. 142 (5): 577–595.e7. doi:10.1016/j.ajodo.2012.05.016. PMID 23116500.

External links 2011 United States government report on implant safety

Worked examples

Example 1 — a first encounter with Implant failure

Start with the simplest possible case. Write down what Implant failure claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Implant failure before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Implant failure ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Implant failure

In research: Implant failure appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Implant failure in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Implant failure is common in secondary-school and first-year university syllabi. It links to neighbouring topics Implants (medicine), Medical error, Product safety, so understanding it makes those chapters shorter.
In everyday life: Look for Implant failure outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Implant failure in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Implant failure means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Implant failure out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Implant failure in simple terms?

Implant failure refers to the failure of any medical implant to meet the claims of its manufacturer or the health care provider involved in its installation. Implant failure can have any number of causes.

Why does Implant failure matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Implant failure?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Implant failure.