Assessment of Platelet Rich Fibrin Efficiency on Healing Delay and on Jawbone Osteochemonecrosis Provoked by Bisphosphonates

Inclusion Criteria: * Patient major(male or female) * Documented indication at the initial visit at day 0 (JO) for a maximum extraction of 3 teeth. * Treatment with nitrogenous or non-nitrogenous BP by intravenous injection or oral administration whichever the reason for this drug prescription: * on going BP treatment * patient having received a previous treatment with bisphosphonates (irrespective of the duration and withdrawal date of this treatment) * Patient having received the specific information letter regarding the study and having signed the clarified consent form. Exclusion Criteria: * Patient having a maxillary or mandibulary OCN at Day 0(JO) * Positive HIV serology at Day 0(for patients belonging to the PRF group) * Previous history of maxillo-cervico-facial radiotherapy * Patients with estimated survival expectancy shorter than one year * Lack of social security cover * Inability of the patient to respect the study follow-up * Patient having reached his/her majority and under tutelage,trusteeship or protection of the court * Patient whose diagnosis could not be revealed to him/her (especially when the patient or their family expressed this wish).