Evaluation of inferior alveolar nerve regeneration by bifocal distraction osteogenesis with retrograde transportation of horseradish peroxidase in dogs

Background: Bifocal distraction osteogenesis has been shown to be a reliable method for reconstructing segmental mandibular defects. However, there are few reports regarding the occurrence of inferior alveolar nerve regeneration during the process of distraction. Previously, we reported inferior alveolar nerve regeneration after distraction, and evaluated the regenerated nerve using histological and electrophysiological methods. In the present study, we investigated axons regenerated by bifocal distraction osteogenesis using retrograde transportation of horseradish peroxidase in the mandibles of dogs to determine their type and function. Methods and Findings: Using a bifocal distraction osteogenesis method, we produced a 10-mm mandibular defect, including a nerve defect, in 11 dogs and distracted using a transport disk at a rate of 1 mm/day. The regenerated inferior alveolar nerve was evaluated by retrograde transportation of HRP in all dogs at 3 and 6 months after the first operation. At 3 and 6 months, HRP-labeled neurons were observed in the trigeminal ganglion. The number of HRP-labeled neurons in each section increased, while the cell body diameter of HRP-labeled neurons was reduced over time. Conclusions: We found that the inferior alveolar nerve after bifocal distraction osteogenesis successfully recovered until peripheral tissue began to function. Although our research is still at the stage of animal experiments, it is considered that it will be possible to apply this method in the future to humans who have the mandibular defects. © 2014 Shogen et al.Evaluation of Inferior Alveolar Nerve Regeneration by Bifocal Distraction Osteogenesis with Retrograde Transportation of Horseradish Peroxidase in Dogs. Shogen Y, Isomura ET, Kogo M. PLOS ONE 2014. 9(4) e94365. doi:10.1371/journal.pone.009436

Molecular Analysis of Salivary Gland Branching Morphogenesis

AbstractRecently, clinicians and scientists have focused on tissue engineering for regenerative medical therapy. This approach promises to provide remarkable clinical breakthroughs for the future. In oral and craniofacial medicine, most scientific approaches to tissue engineering currently involve tooth and bone, while little progress has been made toward regenerating organs such as salivary gland. To develop strategies for salivary gland regeneration, it will be important to understand the molecular mechanisms of normal salivary development. This mini-review describes a recently developed and tested set of approaches for identifying and characterizing molecules essential for branching morphogenesis and other developmental processes. It shows the value of using laser microdissection and the new process of T7-SAGE for gene discovery of putative candidate molecules that may be crucial regulators or mediators. We describe a stepwise series of associated strategies for reliable identification and functional testing of a candidate molecule, as well as its successful application to a specific candidate molecule originally identified by T7-SAGE

Lectin histochemistry of posterior lingual glands of developing rats

The posterior lingual glands are classified as Weber and von Ebner glands. Glycans play an important role in salivary glands. Although the distribution of glycans can explain functional diversity and variation, there are many unknowns in the developing rat posterior lingual glands. The purpose of this study was to elucidate the relationship between the development and function of the posterior lingual gland in rats by histochemical analysis using lectins that bind to sugar residues. In adult rats, Arachis hypogaea (PNA), Glycine maximus (SBA), and Triticum vulgaris (WGA) were associated with serous cells and Dolichos biflorus (DBA) with mucous cells. In both Weber's and von Ebner's glands, all 4 lectins were bound to serous cells in early development, but as development progressed, DBA disappeared in serous cells and only the DBA remained in mucous cells. These results suggest that Galβ (1,3) > Galβ(1,4) > Gal, αGalNAc > αGal > βGalNAc, NeuAc > (GalNAc)2–3>>>GlcNAc, and GalNAcα(1,3) are present in the early stage of development, but that GalNAcα(1,3) disappear in serous cells and only GalNAcα(1,3) are localized in mucous cells after maturation. These results indicate that Weber glands function as serous glands in the early postnatal stage when von Ebner glands have not matured.Harada K., Miki K., Tanaka S., et al. Lectin histochemistry of posterior lingual glands of developing rats. Scientific Reports 13, 10365 (2023); https://doi.org/10.1038/s41598-023-36154-9

Endoscopic soft palate augmentation using injectable materials in dogs to ameliorate velopharyngeal insufficiency

Background Velopharyngeal structure augmentation methods are used as alternatives to pharyngeal flap operations. Recently, we investigated the sites of velopharyngeal structure augmentation in dogs and reported that the most effective injection location is the soft palate. However, there have been no reports regarding the optimal materials for implantation or injection. In this study, we aimed to investigate the injectable materials used in soft palate augmentation in dogs to ameliorate velopharyngeal insufficiency (VPI). Methods Endoscopic soft palate augmentation (ESPA) was performed in dogs using purified sodium hyaluronate, atelocollagen, or autogenic fat tissue. ESPA is an original technique developed by our group, and this is the first report of its performance. Moreover, we assessed the amount of nasal air leakage during inspiration at rest and during expiration under the rebreathing system at 1, 2, 3, 4, 5, and 6 months after injection of these materials. Results The amount of nasal air leakage during expiration under the rebreathing system was significantly decreased in all dogs injected with the ESPA materials, but neither apnea nor hypopnea was observed. Conclusions We investigated the optimal materials for use in ESPA, such as purified sodium hyaluronate, atelocollagen, or autogenic fat tissue. We found that all of them reduced nasal air leakage and only autogenic fat tissue showed significant histologic differences in dogs at 6 months. This technique may also be useful for the treatment of patients with VPI.Endoscopic soft palate augmentation using injectable materials in dogs to ameliorate velopharyngeal insufficiency. Isomura ET, Matsukawa M, Nakagawa K, Mitsui R, Kogo M. PLOS ONE. 2020. 15(9) e0238646. doi:10.1371/journal.pone.023864

Evaluation of sites of velopharyngeal structure augmentation in dogs for improvement of velopharyngeal insufficiency

Background Velopharyngeal structure augmentation methods are used as alternatives to velopharyngeal plasty. Anatomic sites of implantation/injection vary widely due to a lack of standardized criteria. Here, we experimentally investigated optimal sites of velopharyngeal structure augmentation via saline injection in dogs as they naturally exhibit velopharyngeal insufficiency (VPI). Methods Velopharyngeal structure augmentation was performed on 10 beagles (age range: 20–24 months; weight range: 9–12 kg). Saline containing 1/80,000 epinephrine was injected intraorally in 1-mL increments into the nasal mucosa of the soft palate (n = 4), posterior pharyngeal wall (n = 3), or bilateral pharyngeal walls (n = 3) of each dog. Nasal air leakage was measured under rebreathing until velopharyngeal closure was achieved; the measurement was performed using flow meter sensors on both nasal apertures, and the oral cavity was filled with alginate impression material to prevent oral air leakage. Results Pre-injection, the dogs exhibited an average of 0.455 L/s air leakage from the nasal cavity. The dogs with saline injected into the nasal mucosa of the soft palate achieved steady augmentation, and nasal air leakage disappeared under rebreathing following 6-mL saline injection. Conversely, nasal air leakage remained in the dogs with saline injected in the posterior pharyngeal wall or bilateral pharyngeal walls. Conclusions During VPI treatment in dogs, augmentation was most effective at the nasal mucosa of the soft palate. Improvement in nasal air leakage was highly dependent on the saline injection volume. Although velopharyngeal structures vary between dogs and humans, velopharyngeal closure style is similar. Thus, our results may aid in the treatment of VPI patients.Evaluation of sites of velopharyngeal structure augmentation in dogs for improvement of velopharyngeal insufficiency. Isomura ET, Nakagawa K, Matsukawa M, Mitsui R, Kogo M. PLOS ONE. 2019. 14(2) e0212752. doi:10.1371/journal.pone.021275

TGF-β in jaw tumor fluids induces RANKL expression in stromal fibroblasts

Odontogenic tumors and cysts, arising in the jawbones, grow by resorption and destruction of the jawbones. However, mechanisms underlying bone resorption by odontogenic tumors/cysts remain unclear. Odontogenic tumors/cysts comprise odontogenic epithelial cells and stromal fibroblasts, which originate from the developing tooth germ. It has been demonstrated that odontogenic epithelial cells of the developing tooth germ induce osteoclastogenesis to prevent the tooth germ from invading the developing bone to maintain its structure in developing bones. Thus, we hypothesized that odontogenic epithelial cells of odontogenic tumors/cysts induce osteoclast formation, which plays potential roles in tumor/cyst outgrowth into the jawbone. The purpose of this study was to examine osteoclastogenesis by cytokines, focusing on transforming growth factor-β (TGF-β), produced by odontogenic epithelial cells. We observed two pathways for receptor activator of NF-κB ligand (RANKL) induction by keratocystic odontogenic tumor fluid: the cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) pathway through interleukin-1α (IL-1α) signaling and non-COX-2/PGE2 pathway through TGF-β receptor signaling. TGF-β1 and IL-1α produced by odontogenic tumors/cysts induced osteoclastogenesis directly in the osteoclast precursor cells and indirectly via increased RANKL induction in the stroma

Inhibition of invasion and metastasis in oral cancer by targeting urokinase-type plasminogen activator receptor

金沢大学医学部附属病院There have been reports of strong correlations between poor prognosis in various cancers and concomitant expression of urokinase-type plasminogen activator (uPA) and its surface receptor (uPAR). We and others have previously shown that the uPA system plays a significant role in a subset of head and neck squamous cell carcinoma. In the present study, we found that uPAR is required for invasion and metastasis of highly malignant oral cancer cells (OSC-19). Treating OSC-19 cells with antisense oligonucleotides (AS) targeting uPAR resulted in a dramatic decrease of uPAR mRNA expression. Furthermore, pretreatment with AS or siRNA targeting uPAR inhibited progression of OSC-19 cells in experimental models. These results suggest that overexpression of uPAR increases the invasiveness and metastasis of OSC-19 cells, and that uPAR is a promising therapeutic target for regulation of progression of oral cancer

Best practices for the diagnosis and evaluation of infants with robin sequence:a clinical consensus report

Importance: Robin sequence (RS) is a congenital condition characterized by micrognathia, glossoptosis, and upper airway obstruction. Currently, no consensus exists regarding the diagnosis and evaluation of children with RS. An international, multidisciplinary consensus group was formed to begin to overcome this limitation. Objective: To report a consensus-derived set of best practices for the diagnosis and evaluation of infants with RS as a starting point for defining standards and management. Evidence Review: Based on a literature review and expert opinion, a clinical consensus report was generated. Findings: Because RS can occur as an isolated condition or as part of a syndrome or multiple-anomaly disorder, the diagnostic process for each newborn may differ. Micrognathia is hypothesized as the initiating event, but the diagnosis of micrognathia is subjective. Glossoptosis and upper airway compromise complete the primary characteristics of RS. It can be difficult to judge the severity of tongue base airway obstruction, and the possibility of multilevel obstruction exists. The initial assessment of the clinical features and severity of respiratory distress is important and has practical implications. Signs of upper airway obstruction can be intermittent and are more likely to be present when the infant is asleep. Therefore, sleep studies are recommended. Feeding problems are common and may be exacerbated by the presence of a cleft palate. The clinical features and their severity can vary widely and ultimately dictate the required investigations and treatments. Conclusions and Relevance: Agreed-on recommendations for the initial evaluation of RS and clinical descriptors are provided in this consensus report. Researchers and clinicians will ideally use uniform definitions and comparable assessments. Prospective studies and the standard application of validated assessments are needed to build an evidence base guiding standards of care for infants and children with RS

A case of focal osseous dysplasia arising from an impacted tooth located in the maxillary sinus

We report a case of focal osseous dysplasia located in the maxillary sinus. A 45-year-old woman was referred to our clinic because of discomfort in the left side of the maxilla. Radiographic examinations revealed a massive mixed radiopaque lesion measuring approximately 3 × 2 cm with an impacted left wisdom tooth in the left maxillary sinus. The lesion was removed under general anesthesia. Histopathological examination of the surgical specimen revealed cementum-like and bone-like material surrounding the impacted tooth. On the basis of the clinical, radiographic and histopathological findings, the lesion was diagnosed as focal osseous dysplasia.増田 智丈, 磯村 恵美子, 沢井 奈津子, 岸野 万伸, 飯田 征二, 古郷 幹彦, 埋伏歯を伴い上顎洞内に位置した限局性骨性異形成症の1例, 日本口腔外科学会雑誌, 2010, 56 巻, 3 号, p. 194-198, 公開日 2013/10/19, Online ISSN 2186-1579, Print ISSN 0021-5163, https://doi.org/10.5794/jjoms.56.194