Innovations in surgical techniques have improved the esthetic outcome and predictability of root coverage procedures in recent years. A free gingival graft (FGG) augments the attached gingiva, but the compromised blood supply precludes its use in root coverage. In the surgical technique described in this case report, the FGG kept over a laterally placed periosteal flap enhanced the outcome. A laterally flipped periosteal flap was adapted over the root surface using resorbable sutures. The free graft was secured at the recipient site with cyanoacrylate adhesive, and adaptation was ensured with suspensory sutures. Satisfactory root coverage was appreciated and maintained at 6 months with excellent functional outcomes. Adequate width of the attached gingiva and vestibular depth were also noticed at the recipient site. The patient was highly satisfied with the obtained results, which were maintained until the 1-year postoperative period.

Introduction  Myringoplasty is a common otologic procedure to restore the integrity of the tympanic membrane in cases of traumatic or pathologic perforations. Many grafting materials have been used with different techniques. Objective  In the present work, we evaluate the surgical and audiological outcomes of periosteal graft overlying the mastoid cortex through a retroauricular incision in a pediatric cohort. Methods  A retrospective study was carried out involving all children aged ≤ 16 years who underwent periosteal graft myringoplasty for the treatment of chronic suppurative otitis media with dry central perforation in our hospital from April 2019 to April 2021. All patients were followed up for one year to assess the anatomical success and functional outcomes by comparing the preoperative and postoperative (after six months) results of pure tone audiometry (PTA). Results  The sample was composed of 36 patients; 20 of them were female (55.6%) and 16 were male (44.4%) subjects, with ages ranging from 7 to 16 (mean: 12.7) years. Four patients underwent surgery in both ears (with an interval of 6 to 9 months). Out of 40 surgeries performed, 38 ears have shown anatomical success (95%). A highly significant improvement in hearing was obtained (the mean difference between the pre- and postoperative results of the PTA was of 14.6 ± 3.45 dB ( p  < 0.001). Conclusion  We advocate the use of periosteal graft in the pediatric population as a good alternative for other types of grafts, with comparable and even better functional and anatomical outcomes.

OBJECTIVE: Following a mild traumatic brain injury (mTBI), the most prevalent and profoundly debilitating occurrence is the emergence of an acute and persistent post-traumatic headache (PTH), for which there are presently no approved treatments. A crucial gap in knowledge exists regarding the consequences of an mTBI, which could serve as a foundation for the development of therapeutic approaches. The activation of trigeminal sensory nerve terminals that innervate the calvarial periosteum (CP)-a densely innervated tissue layer covering the calvarial skull-has been implicated in both migraines and PTHs. We have previously shown that trigeminal oxytocin receptors (OTRs) may provide a therapeutic target for PTHs. This study examined the expression of oxytocin receptors on trigeminal nerves innervating the periosteum and whether these receptors might serve as a therapeutic target for PTHs using a direct application of oxytocin to the periosteum in a rodent model of PTH.
METHODS: We used retrograde tracing and immunohistochemistry to determine if trigeminal ganglion (TG) neurons innervating the periosteum expressed OTRs and/or CGRPs. To model the impact of local inflammation that occurs following an mTBI, we applied chemical inflammatory mediators directly to the CP and assessed for changes in immediate-early gene expression as an indication of neuronal activation. We also determined whether mTBI would lead to expression changes to OTR levels. To determine whether these OTRs could be a viable therapeutic target, we assessed the impact of oxytocin injections into the CP in a mouse model of PTH-induced periorbital allodynia.
RESULTS: The results of these experiments demonstrate the following: (1) the cell bodies of CP afferents reside in the TG and express both OTRs and CGRPs; (2) inflammatory chemical stimulation of the periosteum leads to rapid activation of TG neurons (phospho-ERK (p-ERK) expression), (3) mTBI-induced inflammation increased OTR expression compared to the sham group; and (4) administration of oxytocin into the periosteum on day 2 and day 40 blocked cutaneous allodynia for up to one hour post-administration for both acute and persistence phases in the PTH model-an effect that was preventable by the administration of an OTR antagonist.
CONCLUSIONS: Taken together, our observations suggest that periosteal trigeminal afferents contribute to post-TBI craniofacial pain, and that periosteum tissue can be used as a potential local target for therapeutics such as oxytocin.

The aim of this study is to validate a minimally invasive surgical procedure to harvest palate periosteum as a source of tissue for mesenchymal stromal/stem cells. We performed a standardized procedure to harvest the palate periosteum in ten subjects, which consisted of a 3 mm disposable punch and a Molt periosteal elevator to harvest a small full-thickness fragment of soft tissue at the hard palate area, between the upper bicuspids, 3 to 4 mm apical to the cement enamel junction. The one-third inner portion was fragmented, and following standard cell culture procedures, the adherent cells were cultured for three passages, after obtaining 70-90% confluence. Cell morphology analysis, flow cytometry analysis, and viability and osteogenic differentiation assays were performed. In all 10 cases, uneventful healing was observed, with no need for analgesic intake. The evaluation of cell morphology showed elongated spindle-shaped cells distributed in woven patterns. A high viability range was verified as well as an immunophenotype compatible with mesenchymal stem cell lineage. The differentiation assay showed the potential of the cells to differentiate into the osteogenic lineage. These results demonstrate that the minimally invasive proposed surgical technique is capable of supplying enough periosteum source tissue for stem cell culture and bone tissue engineering.

Congenital pseudarthrosis of the forearm poses a considerable challenge because of its rarity. The objective of this report is to introduce a novel surgical technique for its treatment. Here, we document a case of congenital pseudarthrosis of the radius in a 3-year-old boy diagnosed with type-1 neurofibromatosis. The surgical treatment involved the excision of approximately 9 cm of native radial periosteum and a bifocal radius osteotomy, which was supplemented with a vascularized tibial periosteal transplant to facilitate bone healing. Anastomosis between the anterior tibial vessels and radial vessels was performed. No immediate or late postoperative complications were observed. After 3 weeks, a robust callus formation was observed, and during a follow-up examination 3 years and 4 months later, a wide range of active forearm rotation was noted. This report suggests that vascularized periosteal flaps show promise as a viable treatment option for congenital pseudarthrosis of the forearm. They offer an alternative to vascularized fibular grafts or single-bone forearm constructs.

In periodontal care, where patient results are crucial in guiding the development of surgical techniques, gingival recession management is a critical issue. The periosteum eversion technique (PET) emerges as a modern strategy that leverages the intrinsic regenerative capabilities of the periosteum to attain root coverage. A detailed case study showcases the effectiveness of PET in managing a Miller Class I gingival recession alongside an adjunctive platelet-rich fibrin (PRF) procedure. This approach entailed the deliberate elevation and eversion of the periosteal flap to encompass the recession area, securing it meticulously through suturing. Across a six-month observation period, this method exhibited successful root coverage, augmentation of keratinized tissue, and enhanced patient comfort, as reported, with no significant complications observed. These outcomes provide support for the incorporation of PET into standard periodontal protocols, underscoring its capacity to reshape the treatment landscape for gingival recession.

Cell surface marker expression is one of the criteria for defining human mesenchymal stem or stromal cells (MSC) in vitro. However, it is unclear if expression of markers including CD73 and CD90 reflects the in vivo origin of cultured cells. We evaluated expression of 15 putative MSC markers in primary cultured cells from periosteum and cartilage to determine whether expression of these markers reflects either the differentiation state of cultured cells or the self-renewal of in vivo populations. Cultured cells had universal and consistent expression of various putative stem cell markers including > 95% expression CD73, CD90 and PDPN in both periosteal and cartilage cultures. Altering the culture surface with extracellular matrix coatings had minimal effect on cell surface marker expression. Osteogenic differentiation led to loss of CD106 and CD146 expression, however CD73 and CD90 were retained in > 90% of cells. We sorted freshly isolated periosteal populations capable of CFU-F formation on the basis of CD90 expression in combination with CD34, CD73 and CD26. All primary cultures universally expressed CD73 and CD90 and lacked CD34, irrespective of the expression of these markers ex vivo indicating phenotypic convergence in vitro. We conclude that markers including CD73 and CD90 are acquired in vitro in most \'mesenchymal\' cells capable of expansion. Overall, we demonstrate that in vitro expression of many cell surface markers in plastic-adherent cultures is unrelated to their expression prior to culture.

We present a transcriptomic analysis that provides a better understanding of regulatory mechanisms within the healthy and injured periosteum. The focus of this work is on characterizing early events controlling bone healing during formation of periosteal callus on day 3 after fracture. Building on our previous findings showing that induced Notch1 signaling in osteoprogenitors leads to better healing, we compared samples in which the Notch 1 intracellular domain is overexpressed by periosteal stem/progenitor cells, with control intact and fractured periosteum. Molecular mechanisms and changes in skeletal stem/progenitor cells (SSPCs) and other cell populations within the callus, including hematopoietic lineages, were determined. Notably, Notch ligands were differentially expressed in endothelial and mesenchymal populations, with Dll4 restricted to endothelial cells, whereas Jag1 was expressed by mesenchymal populations. Targeted deletion of Dll4 in endothelial cells using Cdh5CreER resulted in negative effects on early fracture healing, while deletion in SSPCs using α-smooth muscle actin-CreER did not impact bone healing. Translating these observations into a clinically relevant model of bone healing revealed the beneficial effects of delivering Notch ligands alongside the osteogenic inducer, BMP2. These findings provide insights into the regulatory mechanisms within the healthy and injured periosteum, paving the way for novel translational approaches to bone healing.

BACKGROUND: Reconstructive microsurgery techniques using vascularized bone grafts have revolutionized the treatment of complex cases associated with recalcitrant non-unions or osteomyelitis. The medial femoral corticoperiosteal flap (MFCP flap) has emerged as a valuable option in bone reconstruction. Its clinical applications have been extended over the years considering this flap from non-unions with minimal bone lost, up to large intercalary defects of the upper and lower extremities. This article aims to present the clinical applications and outcomes of the MFCP flap in various reconstructive scenarios.
METHODS: Seventy-nine patients with persistent non-union and bone defects of the upper and lower limb were evaluated from June 2008 to October 2020. All of them were reconstructed with a corticoperiosteal flap from the medial femoral condyle in our hospital. Previous procedures, bone gap and type of flap used were recorded. Postoperative functional status was assessed with time of bone healing, complications and clinical final outcome.
RESULTS: Radiological evidence of bone union was observed at 4.09 months (range 2-9). Healing rate was 97% with periosteal corticocancellous flaps (PCC flaps) and 93% with corticoperiosteal flaps (CP flaps). Average follow-up was 14.5 months (range 5-28). There were no significant donor site complications.
CONCLUSIONS: The MFCP flap offers a versatile and reliable option for bone reconstruction. Its ability to provide vascularized bone tissue with low morbidity enhances the healing process and improves outcomes. The MFCP flap has been increasing its applications and it serves as a valuable option in the treatment of recalcitrant non-unions or bony defects irrespective of site and size up to 5 cm in the upper and lower extremities.

Bone injury is often associated with tears in the periosteum and changes in the internal stress microenvironment of the periosteum. In this study, we investigated the biological effects of periosteal prestress release on periosteum-derived cells (PDCs) and the potential mechanisms of endogenous stem cell recruitment. Decellularized periosteum with natural extracellular matrix (ECM) components was obtained by a combination of physical, chemical, and enzymatic decellularization. The decellularized periosteum removed immunogenicity while retaining the natural network structure and composition of the ECM. The Young\'s modulus has no significant difference between the periosteum before and after decellularization. The extracted PDCs were further composited with the decellularized periosteum and subjected to 20% stress release. It was found that the proliferative capacity of PDCs seeded on decellularized periosteum was significantly enhanced 6 h after stress release of the periosteum. The cell culture supernatant obtained after periosteal prestress release was able to significantly promote the migration ability of PDCs within 24 h. Enzyme-linked immunosorbnent assay (ELISA) experiments showed that the expression of stroma-derived factor-1α (SDF-1α) and vascular endothelial growth factor (VEGF) in the supernatant increased significantly after 3 h and 12 h of stress release, respectively. Furthermore, periosteal stress release promoted the high expression of osteogenic markers osteocalcin (OCN), osteopontin (OPN), and collagen type I of PDCs. The change in stress environment caused by the release of periosteal prestress was sensed by integrin β1, a mechanoreceptor on the membrane of PDCs, which further stimulated the expression of YAP in the nucleus. These investigations provided a novel method to evaluate the importance of mechanical stimulation in periosteum, which is also of great significance for the design and fabrication of artificial periosteum with mechanical regulation function.