Effect of different doses and durations of teriparatide therapy on resolution of medication-related osteonecrosis of the jaw: A randomized, controlled preclinical study in rats.

OBJECTIVE: To evaluate the effects of different doses and durations of teriparatide therapy on MRONJ resolution in rats. SUBJECTS AND METHODS: A total of 120 rats that had been affected with MRONJ (after six weekly zoledronate injections and tooth extraction) were randomly divided into eight subgroups: 2, 10, and 20 µg/kg/day teriparatide were administered to L4, M4, and H4 for 4 weeks, and to L8, M8, and H8 for 8 weeks, respectively. C4 and C8 received saline for 4 and 8 weeks, respectively. One week after the final injection, rats were sacrificed and assessed clinically (bone exposure/fistula) and histologically (number of osteocytes in extraction socket and empty lacunae in alveolar bone). RESULTS: MRONJ was clinically improved in 72.2%, 61.5%, and 40% of stage I, II, and III experimental rats, respectively. In the control rats, the results were 20.8% for stage I and no improvement for stages II and III. Aside from L4 and L8, the experimental subgroups had a significantly higher rate of clinical and histological improvement compared with their corresponding controls. There was a significantly higher number of osteocytes and lower number of empty lacunae in M4 and H4 compared with C4, in H4 compared with L4, in M8 and H8 compared with C8, and in H8 compared with L8. CONCLUSION: Teriparatide therapy improved clinical and histological features of MRONJ in a dose-dependent manner, but clinically relevant doses of teriparatide might not be sufficient for MRONJ resolution in rats. Extending the duration of teriparatide therapy from 4 to 8 weeks did not affect treatment outcomes.

Visual phenomena perceived during pars plana vitrectomy under peribulbar block and monitored anaesthesia care.

AIM: To investigate patients' sensory phenomena, especially instrument visualisation, and their emotional reactions during pars plana vitrectomy (PPV) under monitored anaesthesia care (MAC). METHODS: One hundred adults who underwent PPV under MAC plus peribulbar block were prospectively recruited on the day after surgery to complete a questionnaire about sensory phenomena and comfort. Anaesthetics used during surgery were correlated with visual phenomena and patient comfort. Surgeons were asked to predict patient intraoperative comfort and ability to hear. RESULTS: Of the 27% of patients who reported visual phenomena, lights (74%), colours (37%) and moving instruments (17%) were common. Instrument visualisation was not associated with any preoperative or intraoperative variables. Visual phenomena were neutrally received by 98% of patients. Neither the use of the intravenous medications during the peribulbar injection and surgery nor the type of local anaesthesia correlated with perceived level of pain. Sixty-six per cent of patients remembered hearing surgeons talk, and 96% of patients reacted neutrally to voices. Patient reports of intraoperative pain were similar to the surgeon's prediction, and mean discomfort during surgery was mild. CONCLUSIONS: The reported prevalence of intraoperative visual phenomena is low when elicited at the first postoperative visit. Surgeons can reliably predict patients' comfort, and most patients react neutrally to visual and hearing phenomena during PPV under MAC with peribulbar block. The combination of medications used may be responsible for the neutral reception of sensory phenomena.