Short-term perioperative teriparatide therapy for the prevention of medication-related osteonecrosis of the jaw: A randomized, controlled preclinical study in rats

- Four weeks of teriparatide administration starting at the same day or 2 weeks before tooth extraction successfully reduces the incidence of clinical bone exposure at tooth extraction site in rats under treatment with zoledronate.
- Perioperative teriparatide therapy in rats under treatment with zoledronate results in improved new bone formation in the extraction tooth socket and minimal osteonecrosis in surrounding alveolar bone.
- The beneficial effects of two teriparatide therapy protocols (starting at the same day or 2 weeks before tooth extraction) in prevention of MRONJ are not significantly different.

ObjectiveDentoalveolar procedures in patients receiving bisphosphonates and other antiresorptive agents are associated with an increased risk of medication-related osteonecrosis of the jaw (MRONJ). The aim of present study was to evaluate the effects of perioperative teriparatide (TPD) therapy in prevention of MRONJ.Subjects and methodsTwo protocols of TPD therapy were studied. For protocol A, 25 TPD-treated (AT) and 25 control (AC) rats received 5 weekly injection of 0.06 mg/kg zoledronate. At the end of week 5, extraction of bilateral mandibular first molars was performed for all rats, and 4-week TPD (20 μg/kg/day) and saline therapy was started for AT and AC rats, respectively. For protocol B, 25 TPD-treated (BT) and 25 control (BC) rats received 5 weekly injection of 0.06 mg/kg zoledronate. One week later, 4-week TPD and saline therapy was started for BT and BC rats, respectively. Both groups underwent tooth extraction at the end of week 7 of the experiment. All rats were sacrificed 8 weeks after tooth extraction and assessed clinically for bone exposure/fistula, and histologically for density of osteocytes in newly formed bone and empty osteocyte lacunae in alveolar bone.ResultsIncidence of bone exposure/fistula and mean numbers of osteocytes and empty lacunae per 25 mm2 (at 400× magnification) were 20%, 15.36, and 2.63 in AT group; 78%, 5.78, and 6.81 in AC group; 14%, 16.94, and 2.08 in BT group; and 78%, 7.54, and 5.95 in BC group; respectively. The differences between AT and AC and between BT and BC were statistically significant (P < 0.001). However, no statistically significant difference between AT and BT and between AC and BC was found.ConclusionFour weeks of TPD therapy, beginning at the same day or 2 weeks before tooth extraction, had a potential role in prevention of ONJ.