Prevention of BRONJ Using PRGF in a Totally Edentulous Patient Restored With Postextraction Implants: A Case Report.

Abstract

B isphosphonates-related osteonecrosis of the jaw (BRONJ) is a serious dental-medical complication that is seen among individuals undergoing invasive dental procedures such as extractions, implant placement, or other procedures involving bone surgery. In 2003, Marx identified bisphosphonate treatment as a possible contributor to osteonecrosis, and many studies demonstrating a correlation between chronic biphosphonate consumption and osteonecrosis onset have appeared in the literature since then. The risk of BRONJ rises if the patient is taking other drugs such as chemotherapeutic agents, steroids, and antiangiogenic therapies, and it has been hypothesized that rheumatoid arthritis can be a risk factor on its own. In 2014, the term medicationrelated osteonecrosis of the jaw (MRONJ) was introduced, replacing the common expression BRONJ, as this condition can also result from treatment with other antiresorptive (denosumab) and antiangiogenic therapies. The American Association of Oral and Maxillofacial Surgeons (AAOMS) defines MRONJ as a condition of exposed or probable bone in the maxillofacial region without resolution for greater than 8 weeks in patients treated with an antiresorptive and/or an antiangiogenic agent who have not received radiation therapy to the jaws. For patients who have taken an oral bisphosphonate for fewer than 4 years and have also taken corticosteroids or antiangiogenic medications concomitantly or for those who have taken an oral bisphosphonate for more than 4 years with or without associated steroid therapy, the AAOMS guidelines recommend considering discontinuation of the oral bisphosphonate (drug holiday) for at least 2 months before oral surgery, if systemic conditions permit. The antiresorptive should not be restarted until osseous healing has occurred. Marx et al, in 2007, found a direct exponential relationship between the size of the exposed bone and the duration of oral bisphosphonate use, which was also correlated to the morning fasting serum C-terminal cross-linking telopeptide (CTX) test results; CTX is a bone turnover biomarker, and a stratification of relative risk was seen, with CTX values of less than 100 pg/mL representing high risk, CTX values between 100 and 150 pg/mL representing moderate risk, and CTX values greater than 150 pg/mL representing minimal risk. In addition, drug holidays associated with CTX values rising above the 150-pg/mL threshold were observed to correlate either with spontaneous bone healing or a complete healing response after an officebased debridement procedure. Several clinical protocols have been suggested to treat ONJ, and good results have been shown for the use of blood derivates, such as plasma rich in growth factors (PRGF). PRGF seems to permit achievement of better and faster healing, due to the high concentration of platelets and growth factors in the PRGF. This is why its use has been proposed in many different fields of surgery. The aim of this report was to show how a strict protocol based on recording CTX values and using PRGF to enhance healing processes enabled implant-supported prosthetic rehabilitation of a patient with a high risk of MRONJ.