Healing response is sometimes not compromised by disease but medication. One very common type of medication that can interfere with implant therapy is the so-called antiresorptive drugs, a group of pharmaceuticals that have been developed to counter the effects of osteoporosis and osteopenia. The most common and best studied drugs in this group are the bisphosphonates. These drugs have been initially used for the treatment of cancer, but they're widely prescribed to patients with osteoporosis as they can prevent bone resorption and increase bone density. The use of bisphosphonates has been correlated with an osteonecrosis of the jaw, especially in conjunction with invasive procedures such as extraction or minor oral surgery. In cases of patients under bisphosphonates, we need to identify three factors to support our decision making. First, why do patients receive bisphosphonates? Second, which drug do they take and what is the delivery mode? And third, how long have they been under the medication? Today, any patient receiving oral bisphosphonates for the treatment of osteoporosis for five years or less should be considered safe for implant placement. Intravenous delivery of bisphosphonates for the treatment of osteoporosis is gaining popularity. In these cases, the tablets are replaced by one annual intravenous infusion. There is little evidence to suggest increased risk in such cases and caution needs to be exercised evaluating the amount of years the patient has been under treatment. Finally, intravenous delivery of bisphosphonates for the treatment of cancer is increasing significantly the doses and the risk for osteonecrosis and in such cases implant surgery should be completely avoided. A newer drug with increasing popularity is Denosumab, which is a monoclonal antibody. This is a relatively new drug and although it was initially introduced as a safer alternative to bisphosphonates, it appears it is also increasing the risk for osteonecrosis. As this is a new drug and we have little evidence of its potential risks, extreme caution should be exercised prior to deciding implant therapy for such patients. Furthermore, we have certain conditions that might be compatible with health, but they indicate susceptibility and consequently an increased risk for failures. A typical example of such a condition is the history of periodontitis, describing patients who have been in the past diagnosed with periodontitis, even if they currently enjoy good gingival health. Several studies have shown that such patients are significantly more likely to develop peri-implant disease as well. However, this does not mean that such patients should be excluded from dental implants. History of periodontitis is an indicator of susceptibility of the patient to periodontal and peri-implant inflammations. With a good level of oral hygiene and a regular maintenance scheme, such patients can also enjoy highly successful and sustainable treatment outcomes. So history of periodontitis is not a contraindication, but it is a warning signal. Other conditions where implants should be avoided is cases of young individuals with residual skeletal growth or patients with limited compliance. Remember, despite significant progress, we are still far away from providing a treatment suitable for every patient with missing teeth. Implants remain a high maintenance device and require a significant lifetime commitment from the side of the patient. Careful patient selection and risk assessment remains the cornerstone of success.
