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Objective: This study aimed to investigate (1) the temporal pattern of ferroptosis, an iron‐dependent cell death, in ligation‐induced rat periodontitis and (2) the effect of ferrostatin‐1, a ferroptosis inhibitor, on the model. Background: Ferroptosis may contribute to various diseases. However, the role of ferroptosis in periodontitis is still fully understood. Methods: In the first experiment, 25 rats with ligation‐induced periodontitis were sacrificed on days 0, 1, 2, 7, and 10. Gingivae were obtained to determine tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, and ferroptotic biomarkers, including solute carrier family 3 member 2 (SLC3A2) and solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (Gpx4), via immunoblotting. Using microcomputed tomography (μCT) and histology, the periodontal soft and hard tissue lesions, including dental alveolar bone crest level, bony characteristics of the surrounding alveolus, periodontal tissue inflammation, and periodontal tissue losses, were evaluated. In study two, 16 rats with induced periodontitis were grouped according to ferrostatin‐1 treatment. The rats were intraperitoneally injected with solvent or ferrostatin‐1 (1.5 mg/kg/day) 1 day before ligation and sacrificed on days 7 and 10. Gingival protein changes and periodontal tissue damage were also examined. Results: In study one, SLC3A2/SLC7A11 and Gpx4 decreased since day 1; however, TNF‐α/IL‐1β increased on days 7 and 10. Moreover, the μCT/histology revealed resorptive bony characteristics, inflamed gingival tissue, and periodontal attachment loss. In study two, ferrostatin‐1‐injected rats exhibited significantly increased SLC3A2/SLC7A11 and Gpx4 but decreased TNF‐α/IL‐1β than vehicle rats. They also revealed lessened bone resorption, tissue inflammation, and attachment loss. Conclusion: This study highlights the role of ferroptosis, via the system Xc/Gpx4 pathway, in experimental periodontitis and may serve as a regulatory strategy. [ABSTRACT FROM AUTHOR]

Background: This study aims to assess whether hyperbaric oxygen (HBO) applied immediately after tooth extraction could ameliorate medication‐related osteonecrosis of the jaw in rats. Methods: To evaluate whether osteonecrosis could be successfully induced, healing of extraction maxillary molars was examined in 40 female Sprague Dawley rats received zoledronic acid (7.5 µg/kg) plus dexamethasone (1 mg/kg). Rats were divided into four groups, receiving zero, two, four, or seven injection(s) for 7 days, respectively. Effect of HBO, pressurized to 2.5 atmospheres absolute (ATA) at rate of 0.15 ATA/min with 100% oxygen for 90 minutes, applied immediately after tooth extraction, on the development of osteonecrosis was evaluated. Lesions among groups were compared by size of ulceration, exact area (mm2) or relative area (%), and by histology. Results: Unhealed ridge was observed in all nine rats in four and seven injection groups, but none of 10 rats in the control (non‐injection) group. Immediate HBO significantly reduced the lesions in rats that received four injections, regardless of the distribution and the total/relative areas of lesions (P <0.01). Histological findings showed the lesions were uncovered epithelium and severe tissue inflammation. Conclusion: This is the first in vivo study demonstrating the HBO applied immediately after tooth extraction effectively decreases the development of medication‐related osteonecrosis. [ABSTRACT FROM AUTHOR]

Objective: Numerous patients in Taiwan with tongue carcinoma require tongue reconstruction. We compared the abilities of 2 methods of tongue reconstruction to reserve tongue function.Study Design and Setting: Sixty patients underwent resection of the tumors and reconstruction with a pectoralis major flap or a radial forearm flap. The Chinese articulation test was used to evaluate the place and manner of error production, and a questionnaire on dietary habits was used to evaluate deglutition 6 months to 10 years after reconstruction.Results: Patients with the free flap had more intelligible speech. The questionnaire study showed no significant difference between the 2 groups in swallowing rating. Motility caused by flap pliability increased speech intelligibility more than it did on swallowing function.Conclusion: Our experience in a few selected patients shows that the functional outcome of tongue surgery is related to the reconstruction methods used (for speech) and to the extent of tongue resection (for swallowing). (Otolaryngol Head Neck Surg 2003;128:412-8.) [Copyright &y& Elsevier]