Oral administration of bisphosphonates does not increase the risk of osteonecrosis of the jaw, according to data presented at the 89th General Session and Exhibition of the International Association for Dental Research. The findings were based on a combined retrospective and prospective study, said Marjorie K. Jeffcoat, DDS, of the University of Pennsylvania, USA: We analyzed data from a database of millions of patients and studied hundreds of patients in controlled clinical trials, and none of the results found an increased risk of osteonecrosis with oral bisphosphonates. However, the study found a six-fold increased risk of osteonecrosis of the jaw in patients who used intravenous bisphosphonates. Many other studies have found a strong correlation between intravenous bisphosphonates and osteonecrosis, but whether oral bisphosphonates carry the same risk is controversial, and the American Association of Oral and Maxillofacial Surgeons recommends that certain patients should be considered off oral bisphosphonates before oral surgery. To obtain prospective data, Jeffcoat and colleagues conducted three randomized, double-blind, placebo-controlled clinical trials involving a total of 516 patients. All of these patients took oral bisphosphonates (alendronate or risedronate) for several years, and of these patients, 386 had periodontitis and 130 required oral implants. These patients were examined every 3 months for signs of osteonecrosis of the jaw. As a result, none of the patients progressed to osteonecrosis of the jaw, whether they were treated with oral bisphosphonates or placebo. The researchers also conducted a retrospective analysis of a database of more than 55 million cases, which included nearly 70 U.S. health plans between 2000 and 2006, and divided the patients into three groups: intravenous, oral bisphosphonates or no bisphosphonates, all of whom were followed up for at least six months. The results showed that the risk ratio (OR) for osteonecrosis with oral bisphosphonates was 1.03, while the OR for osteonecrosis with intravenous bisphosphonates was as high as 6.02. Dr. Jeffcoat believes that patients with osteoporosis and their dentists should not be concerned about the impact of oral bisphosphonates on dental procedures, and that the addition of bisphosphonates remains an important therapy for the treatment of osteoporosis.