Oral transmucosal absorption of iodine after intraoral preparation with povidone-iodine prior to oral surgeries: a randomized controlled study in 12 male patients.

INTRODUCTION: Absorption of iodine through skin and an increased incidence of thyroid disorders due to iodophor exposure are reported. However, the risk of oral transmucosal absorption of povidone-iodine after intraoral preparation is not clear. OBJECTIVE: To investigate the possibility of oral transmucosal absorption of povidone-iodine after intraoral preparation and its effect on thyroxine level in blood. PATIENTS AND METHODS: A randomized controlled study was carried out in the department of oral and maxillofacial surgery. Twenty- to 40-year-old healthy male adults planning to receive oral surgery under general anesthesia were enrolled. The study group received povidone-iodine irrigation of oral cavity for 3 min as intraoral preparation before operation. The control group received chlorhexidine gluconate irrigation of oral cavity for 3 min as intraoral preparation before operation. Iodine levels in blood and urine, and thyroxine levels in blood were tested and compared, before and after operation. RESULT(S): In total, 24 patients were included and analyzed finally. We found that after intraoral preparation with povidone-iodine, serum iodine level increased significantly to 2-3 times the pre-operation level in 15-30 min, and the urinary iodine level increased to 5 times the pre-operation level on the first day after operation. Iodine levels in blood and urine decreased significantly on the third day after operation but still significantly greater than the pre-operation levels. However, thyroxine levels were not altered accordingly. CONCLUSION(S): Oral transmucosal absorption of iodine is observed when povidone-iodine is used for intraoral preparation in healthy male adults, though the free thyroxine in blood is not affected accordingly. CLINICAL RELEVANCE: Povidone-iodine is commonly used as an antiseptic in oral surgery and dental clinics. Based on our findings that iodine levels in blood and urine may elevate significantly after intraoral preparation with povidone-iodine prior to oral surgeries, care must be taken for individuals when excess iodine intakes can endanger the safety of the patient. REGISTRATION INFORMATION: Name of the trial registry: The Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ). Registration number: ChiCTR2100042028.

BMP9-initiated osteogenic/odontogenic differentiation of mouse tooth germ mesenchymal cells (TGMCS) requires Wnt/ß-catenin signalling activity.

Teeth arise from the tooth germ through sequential and reciprocal interactions between immature epithelium and mesenchyme during development. However, the detailed mechanism underlying tooth development from tooth germ mesenchymal cells (TGMCs) remains to be fully understood. Here, we investigate the role of Wnt/ß-catenin signalling in BMP9-induced osteogenic/odontogenic differentiation of TGMCs. We first established the reversibly immortalized TGMCs (iTGMCs) derived from young mouse mandibular molar tooth germs using a retroviral vector expressing SV40 T antigen flanked with the FRT sites. We demonstrated that BMP9 effectively induced expression of osteogenic markers alkaline phosphatase, collagen A1 and osteocalcin in iTGMCs, as well as in vitro matrix mineralization, which could be remarkably blunted by knocking down ß-catenin expression. In vivo implantation assay revealed that while BMP9-stimulated iTGMCs induced robust formation of ectopic bone, knocking down ß-catenin expression in iTGMCs remarkably diminished BMP9-initiated osteogenic/odontogenic differentiation potential of these cells. Taken together, these discoveries strongly demonstrate that reversibly immortalized iTGMCs retained osteogenic/odontogenic ability upon BMP9 stimulation, but this process required the participation of canonical Wnt signalling both in vitro and in vivo. Therefore, BMP9 has a potential to be applied as an efficacious bio-factor in osteo/odontogenic regeneration and tooth engineering. Furthermore, the iTGMCs may serve as an important resource for translational studies in tooth tissue engineering.

Filler found in bone: Surgical removal of polyacrylamide hydrogel (Amazingel) from the mandible after 24 years: A case report and literature review.

Polyacrylamide hydrogel (PAAG) is widely regarded as a safe soft tissue filler and has been extensively utilized for cosmetic enhancements, such as breast and facial augmentation in China from 1997 until its ban in 2006. Common complications associated with its use include inflammation, infection, granulomas, fibrosis, gel migration, and facial and soft tissue deformities. This case report describes a 45-year-old Chinese woman who experienced PAAG migration into her mandible 24 years after facial augmentation, causing irritation of the mandibular alveolar nerve - apparently the first documented instance of this occurrence. Surgical intervention was necessary to remove the migrated gel and associated calcifications. A literature review explored adverse events and management strategies for PAAG complications in cosmetic procedures. While generally considered safe, this report underscores the importance of meticulous injection techniques and careful anatomical site selection to prevent such severe complications.