Understanding Dental Implant Rejection: Causes, Symptoms, and Prevention

dental implant rejection

Dental implant rejection, a phenomenon where the body’s immune system acts against the dental implants, is one of the major causes of failed dental implants.

The causes, symptoms and prevention of dental implant rejection are often misunderstood, causing an inability of the patients to detect and treat it on time. On the other hand, patients can easily spot implant rejection and take measures to fix it by being equipped with the right knowledge about this phenomenon.

Therefore, we’ll discuss all the 3 important aspects of implant rejection (its causes, symptoms, and prevention) so all implant recipients can be on their guard regarding this serious issue, ultimately helping them prevent dental implant failure.

What Is Dental Implant Rejection?

In simple terms, dental implant rejection refers to a condition where the body’s immune system detects the implants as foreign objects in the body and, therefore, initiates an attack against them. 

A lot of patients wonder why this happens, considering the fact that dental implants are made of biocompatible (designed to be accepted by the jawbone and to support implant osseointegration) materials like Titanium and Zirconia. The answer to this question lies in the complex etiology of implant rejection, the reasons for which are not always identifiable or apparent.

The attack mounted by the immune system against dental implants has detrimental consequences on the implant’s stability and functionality, ultimately leading to implant failure. For this reason, it’s important to understand the underlying causes of implant rejection so patients may take care to avoid these causes, and if the rejection has already occurred, then take measures to fix it.

Causes Of Dental Implant Rejection 

We’ve just noted how a failed dental implant is a possibility despite implants being composed of biocompatible materials. Now, let’s explore the potential reasons/causes behind this rejection:

Implant Infection 

Infection, specifically peri-implantitis, is one of the most notable causes of implant rejection. In peri-implantitis, the soft and hard tissue surrounding the implants gets inflamed, leading to swelling, bleeding, and pain, as well as significant bone loss in that area. This infection could be due to several reasons, such as poor oral hygiene, excessive dental adhesive, poor implant placement, etc. Regardless of the cause, the infection invites the immune system to mount an attack against the implants, leading to implant rejection.

Inadequate Jawbone Support 

One of the most important prerequisites for dental implant success is a sufficient and healthy jawbone. This allows the implants to anchor to them and provides adequate support. An absence of a healthy and sufficient jawbone, on the other hand, would lead to weak anchoring of the implants. The causes of jawbone loss include infection (as discussed above), chronic gum disease, trauma, or tooth loss. In any case, jawbone loss causes perpetual instability of the implants and triggers implant failure.

Allergic Reactions

Implants are composed of biocompatible materials, so it’s very unlikely for patients to get allergic reactions to implants. However, in rare cases, some people still experience allergic reactions to implants due to their hypersensitivity towards the implant material. The symptoms of such an allergy include ongoing inflammation, swelling, and pain, which may lead to implant rejection if not treated on time.

Poor Surgical Technique 

The success of full-mouth dental implants heavily hinges on the skill and expertise of the surgeon performing the implant placement surgery. If your surgeon employs poor surgical technique without proper planning and execution (such as incorrect implant placement, inadequate sterilization of implants, ill-fitting of the prosthesis, etc.), then it’s very likely to trigger implant rejection. This is why it’s highly important to choose an expert for your implant treatment who will perform it with utmost precision. 

Medical Conditions

Certain medical conditions (for example, systemic diseases like diabetes, bone disorders like osteoporosis, and autoimmune disorders like arthritis) hinder the successful integration of the implants into the jawbone. This is due to the debilitating effect of these conditions on the body’s healing ability, leading to a compromised immune response. When the implants fail to integrate with the jawbone due to these conditions, it triggers implant rejection and, ultimately, implant failure.

Symptoms Of Dental Implant Rejection 

The common culminating point of all the cases of implant rejection (regardless of the underlying cause) is implant failure, which can be a serious setback to you considering the financial investment you’ve put into implant treatment. To prevent this from happening, it’s important for you to be aware of the symptoms of implant rejection so you may spot the rejection in the early stages and treat it before it leads to implant failure. These symptoms include:

  • Persistent and severe pain that suddenly erupts many days after implant surgery.
  • Chronic inflammation around the implants.
  • Mobility of the implants.
  • Gum recession around the implants.
  • Release of pus or discharge from the implant site.

Prevention Of Dental Implant Rejection 

Prevention of implant rejection means preventing the potential underlying causes of the rejection (which we have discussed above in detail). This can be done by taking the following measures:

Comprehensive Pre-treatment Evaluation 

A lot of cases of implant rejection can be avoided simply by employing a thorough pre-surgical assessment. In this assessment, your surgeon will comprehensively assess your oral profile and analyze your medical history to detect any risk factors that may lead to implant rejection. This includes assessing your jawbone quality and quantity, identifying medical conditions that may interfere with implant integration, etc. This evaluation will also help the surgeon plan the surgical technique with precision. All of this will lead to the prevention of implant rejection. 

Controlling Medical Conditions

If, during pre-surgical assessment, your surgeon establishes that you have certain medical conditions that will interfere with implant success, then it’s important for you to manage these conditions. This may include consulting medical specialists for the treatment of your specific condition and adjusting medication dosage to prevent its impact on bone metabolism.

Optimal Oral Hygiene 

Optimal oral hygiene is essential for implant success. By following a proper oral care routine (such as regular brushing, flossing, using an antibacterial mouthwash, and receiving regular professional dental cleanings) will keep harmful bacteria away from implants. This will prevent the incidence of infection, which will ultimately prevent implant rejection.

Choosing The Best Implant Material

It’s important to select the best implant material based on the specific needs of the patient and his potential for experiencing implant allergies. Generally, titanium and zirconia are the best implant materials that offer optimum biocompatibility. Selecting which one is best suited to your patient’s needs is crucial in preventing potential implant rejection.

Post-operative Care 

Needless to say, diligent post-operative care and monitoring are essential for your implants’ success. This includes following your dentist’s instructions properly, taking the prescribed medications on time, and ensuring that your implants stay protected from internal and external trauma. Also, refrain from behaviors that impair implant healing (such as smoking and alcohol consumption). Doing all of this would promote implant success and reduce the chances of implant rejection. 


Dental implant rejection is an unfavorable occurrence where the body’s immune system starts attacking the implants, leading to implant failure. However, you can steer clear of this unfavorable occurrence by knowing the causes, symptoms, and prevention strategies for implant rejection.

For an in-depth evaluation of your oral profile to determine your suitability for dental implants, feel free to consult with the implant experts practicing at Lexington Implant Clinic, located in Lexington, Kentucky. This FREE consultation will materialize your dream of getting a successful dental transformation.

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