Absolute contraindications for implant rehabilitation are serious medical conditions that can put a patient's life at risk. These include a recent myocardial infarction or stroke, valve prosthesis surgery, immunosuppression, bleeding problems, active treatment of malignancy, drug abuse, psychiatric illnesses, and the use of intravenous bisphosphonates. Relative contraindications are conditions that may increase the risk of implant failure and include cognitive impairment, status IV or higher in American Society of Anesthesiology patients, or medical conditions that may endanger the patient's life or life expectancy. Precautions should be taken when placing dental implants due to evidence-based exposures that may contribute to the risk of failure.
These include local factors such as periodontal disease, smoking, and radiotherapy. Additionally, bruxism (teeth grinding) has been linked to an increased risk of implant failure. The relationship between the survival of dental implants and the use of bisphosphonates has been documented in 5 study reports that evaluated more than 4500 dental implants. In seven primary studies, Shi and his colleagues evaluated the failure rate of 286 dental implants placed in 252 well-controlled diabetics and 301 dental implants placed in poorly controlled patients.
A study of smoking patients recorded 1259 (6.35%) of the 19,836 dental implants placed in smoking patients and 1923 (3.18%) of the 60,464 dental implants placed in non-smokers. In total, 1,330 implants were placed in 528 bisphosphonate users and 2,418 implants were placed in 811 healthy patients. In total, more than 10,000 implants were placed in people with periodontal disease with 3,851 implants placed in 1,606 healthy patients over a period of 1.2 to 10 years. In this analysis, 49 (6.45%) implant failures were detected in patients with Bruxism, compared to 109 (3.65%) in patients without Bruxism. It is important to note that only a specialist can accurately assess a patient's fitness to receive dental implants based on information collected during the initial consultation with the patient (including known contraindications). The risk of a dental implant not working increases in relation to history of periodontal disease (bruising), smoking and radiotherapy. In conclusion, there are few absolute contraindications for the placement of dental implants but relative contraindications should be taken into account when considering implant surgery.
Local factors such as periodontal disease, smoking and radiotherapy can increase the risk of implant failure as can bruxism (teeth grinding). It is important to consult with a specialist before undergoing implant surgery to ensure that all risks are taken into account.