Risk factors of dental implant failure

Martin Wanendeya raises awareness of dental implant failures, so that practitioners can take steps to avoid them

Dental implants are widely used for effectively and predictably replacing damaged or missing teeth, with average survival rates of 95.4% after 10 years.

Dental implants are able to provide functional and aesthetic results superior to removable solutions such as dentures.

Yet, complications can occur from implant treatment that result in dental implant failure and loss of the implant.

Awareness of risk factors that affect a dental implant’s long-term success is essential so you’re better prepared in case something goes wrong.

Taking quick, corrective action enables clinicians to prevent additional and more serious problems from occurring.

Bone quality and quantity

Achieving primary stability is important to ensure the survival of an implant, as this facilitates optimal healing and osseointegration.

Patients at a higher risk of dental implant failure include those with poor bone quality and quantity.

Treatment failure is associated with excessive bone loss and impairment of the healing process.

Slight bone loss over several years is normal and unlikely to affect a patient’s implant directly.

However, a dental implant failure is typically deemed if there is bone loss of more than 1.5mm in the first year following placement, and more than 0.2mm every year after.

Patients that lack adequate bone height, width, or length can undergo a bone grafting procedure to ensure healthy bone mass is available to support osseointegration. Bone grafting can be performed at the same time as or prior to implant placement.

This can greatly improve the functional and aesthetic outcome of treatment.

Oral hygiene and smoking

Peri-implantitis is one of the most common risk factors of dental implant failure, with an estimated prevalence ranging from 10% to 40%.

This inflammatory disease shares some similarities to periodontitis.

It is caused by bacterial colonisation and a subsequent failure to remove this bacteria from the oral cavity.

If left untreated, peri-implantitis can destroy the soft and hard tissue.

This results in deterioration of the bone structure supporting the implant and eventual loss of the implant.

A combination of effective oral hygiene at home and professional dental cleaning within the practice is vital to prevent peri-implantitis.

It is important that patients take some responsibility for disease prevention.

As such, offering patients education on the impact smoking can have on implant treatment – as well as on their general health – helps.

Smoking and dental implant failure

Smoking can negatively affect the oral microbiome.

Potentially, this can alter the peri-implant environment and contribute to the prevalence of peri-implantitis.

Smoking can also impede wound healing following implant surgery. Carbon monoxide produced by cigarette smoke has a higher affinity for haemoglobin, which reduces oxygenation of healing tissue. In addition, the cytotoxic effects of smoking can disrupt body cell repair and defence.

Surgical execution

Another common risk factor of dental implant failure is poor surgical execution during implant placement.

This includes the surgeon overheating the bone – due to the friction caused by high torque surgical equipment.

This damages the implant bone bed and can contribute to dental implant failure.

Poor surgical execution may also refer to improper implant positioning.

This can potentially damage or subject the implant and its components to non-axial loading during mastication.

This increases the risk of implant or peri-implant bone fractures.

They often occur in the posterior of the oral cavity as a result of high load in this region.

Failure due to poor surgical execution of dental implant therapy is easily avoided with proper treatment planning.

Other factors include implant site development, the use of surgical guides and a good understanding of the restorative aspects of the procedure.

This emphasises the importance of having the relevant training and qualifications to provide dental implants. Equally, practitioners can refer patients for implant treatment.

As with any other oral surgical procedure, dental implant therapy is not totally free from complications. Early detection and treatment of potential problems is key to saving dental implants from failure and loss.

Factors that need be considered are bone quality and quantity, oral hygiene, smoking and surgical execution.

As long as practitioners are aware of the risk factors that can affect treatment, they can take steps to mitigate them.

This will ensure the long-term success of dental implants.