Evaluation of the efficacy of EDTA application as A calcium chelating agent at piezosurgery and conventional bur surgery in bisphhosphonate induced rats

Objective: The number of the patients encountered with bisphosphonate related osteonecrosis of the jaw has been increasing according to common use of bisphosphonates for treatment of various disorders. The MRONJ may become resistant and progressive in bone due to releasing for many years after high accumulation. The aim of this study was to investigate the adjunctive role of the piezosurgery, conventional bur surgery and the local administration of EDTA as chelating agent on bone healing after bisphosphonate application. Method: A total of 40 male Wistar rats were randomly allocated into two groups for each surgical procedure as two control (KP, KF) and two study groups (P,F). Study groups received weekly intraperitoneal injections of zoledronic acid (0.06 mg/kg), while control groups were administered saline solution for five weeks. After four weeks, defects were composed on the mandible by using either piezosurgery (P) or conventional burs (F) with dimensions of 4 mm in length and 1 mm in depth. The defects were created bilaterally at the study groups and unilaterally at the control groups. At postoperative 4th week, rats were sacrificated following mandibulectomy. The mandibles with defect areas were conducted for performing the histomorphometric examination to evaluate the consisting bone. The differences between all groups were analyzed statistically. Results: New bone formation was found to be the highest in control groups (p<0,05). There was no statistically significant difference between use of piezosurgery or conventional burs at control groups (p>0,05). Among study groups, the greatest amount of consisting bone was observed at the piezosurgery group which combined with EDTA application (PE), however, no significant difference was observed between any of the study groups (p>0,05). Conclusion: Although the findings of our study fail to show statistically significant differences between groups; it can be concluded that in case of bisphosphonate use, the positive effects of chelating agents and piezosurgery on the healing of the bony tissue observed in this study, should be investigated further in studies with larger sample sizes and different agents. Key words: bisphosphonate, EDTA, MRONJ, piezosurgery, chelation