Maxillofacial Plastic and Reconstructive Surgery最新文献

Background: Mesenchymal stem cell (MSC) therapy gained interest among scientists following the discovery of its therapeutic potential. However, their clinical use has been hindered due to their immunogenicity and tumorigenicity. Relatively recently, it has been unveiled that the mechanism by which MSC promote healing is by secreting exosomes. This raised the interest in developing cell-free therapy, avoiding the obstacles that deterred the translation of MSC therapy into clinical practice.

Review: This comprehensive narrative review summarises the current understanding of exosome biogenesis and content. Moreover, the existing research on exosome use in bone tissue engineering is discussed.

Conclusions: Exosome-based therapy may provide excellent potential in the field of bone tissue engineering and craniofacial reconstructive surgery. Further investigation is required before the technology can be translated into clinical practice.

Background: Surgical ciliated cysts, also known as postoperative maxillary cysts or implantation cysts, occur mainly in the posterior maxilla after radical maxillary sinus surgery; they rarely develop in the mandible. They are thought to occur when the sinonasal epithelium is infiltrated by a surgical instrument during surgery or as a result of transplantation of bone or cartilage with respiratory epithelium attached.

Case presentation: We report a case in which a surgical ciliated cyst developed in the anterior part of the mandible, presumably as a result of bimaxillary orthognathic surgery and genioplasty performed 24 years earlier. We then review the few similar cases reported in the literature.

Conclusion: Surgical ciliated cysts in the mandible are extremely rare, but they could occur after simultaneous surgery on the maxilla and mandible, even decades later. To prevent surgical ciliated cysts in the mandible, we recommend that the surgical instruments, especially the saw blade used during bimaxillary surgery, be new or cleaned and that previously placed plates and screws be removed at an appropriate time.

Background: Gorlin syndrome, also known as Gorlin-Goltz syndrome (GGS) or basal cell nevus syndrome (BCNS) or nevoid basal cell carcinoma syndrome (NBCCS), is an autosomal dominant familial cancer syndrome. It is characterized by the presence of numerous basal cell carcinomas (BCCs), along with skeletal, ophthalmic, and neurological abnormalities. It is essential to anticipate the diagnosis by identifying the pathology through the available diagnostic tests, clinical signs, and radiological manifestations, setting up an adequate treatment plan.

Main body: In the first part, we searched recent databases including MEDLINE (PubMed), Embase, and the Cochrane Library by analyzing the etiopathogenesis of the disease, identifying the genetic alterations underlying them. Subsequently, we defined what are, to date, the major and minor clinical diagnostic criteria, the possible genetic tests to be performed, and the pathologies with which to perform differential diagnosis. The radiological investigations were reviewed based on the most recent literature, and in the second part, we performed a review regarding the existing jawbone protocols, treating simple enucleation, enucleation with bone curettage in association or not with topical use of cytotoxic chemicals, and "en bloc" resection followed by possible bone reconstruction, marsupialization, decompression, and cryotherapy.

Conclusion: To promote the most efficient and accurate management of GGS, this article summarizes the clinical features of the disease, pathogenesis, diagnostic criteria, differential diagnosis, and surgical protocols. To arrive at an early diagnosis of the syndrome, it would be advisable to perform radiographic and clinical examinations from the young age of the patient. The management of the patient with GGS requires a multidisciplinary approach ensuring an adequate quality of life and effective treatment of symptoms.

After tooth extraction, dimensional changes affect the alveolar socket, leading to loss in alveolar bone height and width. Histological modifications also occur, with initial formation of a blood clot that is replaced with granulation tissue and subsequently with a provisional connective tissue matrix. Spontaneous healing ends with socket filling with woven bone, which is gradually replaced with lamellar bone and bone marrow. Adequate alveolar ridge dimensions and bone quality are required to assure optimal stability and osseointegration following dental implant placement. When a tooth is extracted, alveolar ridge preservation (ARP) procedures are an effective method to prevent collapse of the post-extraction socket. Heterologous bone is widely chosen by clinicians for ARP, and anorganic bone xenografts (ABXs) made bioinert by heat treatment represents the most used biomaterial in clinical applications. Collagen-preserving bone xenografts (CBXs) made of porcine or equine bone are fabricated by less invasive chemical or enzymatic treatments to remove xenogenic antigens, and these are also effective in preserving post-extraction sites. Clinical differences between anorganic bone substitutes and collagen-preserving materials are not well documented in the literature but understanding these differences could clarify how processing protocols influence biomaterial behavior in situ. This systematic review of the literature compares the dimensional changes and histological features of ABXs versus CBXs in ridge preservation procedures to promote awareness of different bone xenograft efficacies in stimulating the healing of post-extraction sockets.

Background: Temporal hollowing is a common complication following the rotation of the temporalis muscle that leaves the patient with a cosmetic impairment. Several alloplastic materials have been used to reconstruct the donor site; however, these implants need meticulous adaptation to conform the periphery of the defect and restore the contour of the temporal area. The aim of this study was to assess the use of patient-specific polyetheretherketone (PEEK) temporal implants to prevent temporal hollowing following the use of full temporalis muscle flap for large maxillary defects reconstruction.

Methods: This was a prospective study conducted on eight patients with major maxillary defects indicating the need of reconstruction with full temporalis muscle flap or any lesion indicating major maxillary resection and immediate reconstruction with total temporalis muscle flap. For each patient, a patient-specific PEEK implant was fabricated using virtual planning and milled from PEEK blocks. In the surgical theater, the temporalis muscle was exposed, elevated, and transferred to the maxilla. After the temporalis muscle transfer, PEEK implants were fixed in place to prevent temporal hollowing.

Results: The surgical procedures were uneventful for all patients. The esthetic result was satisfactory with no post-operative complications except in one patient where seroma occurred after 2 weeks and resolved after serial aspiration.

Conclusion: Patient-specific PEEK implant appears to facilitate the surgical procedures eliminate several meticulous steps that are mainly based on the surgeon's experience.

Trial registration: Clinical trials registration: NCT05240963 .

Background: The stability of the results remains a significant concern in orthognathic surgeries. This study aimed to assess the amount of relapse following mandibular advancement with/without maxillomandibular fixation (MMF).

Materials and methods: A single-blind clinical trial was conducted on patients with mandibular retrognathism who underwent BSSO for mandibular advancement and Lefort I maxillary superior repositioning. Patients were randomly divided into two groups of treatment (MMF) and control (no MMF). In the treatment group, MMF was performed for 2 weeks; meanwhile, MMF was not performed in the control group, and only guiding elastics were applied postoperatively. Lateral cephalograms were obtained preoperatively (T1), immediately after surgery (T2), and at 1 year postoperatively (T3). The distance from points A and B to the X and Y plane were measured to identify the amount of vertical and horizontal relapse in 1 year as a primary outcome. An independent t-test was applied in order to find differences in outcomes between the control and treatment groups.

Results: Fifty-eight patients were evaluated in two groups (28 patients in the MMF group and 30 in the no-MMF group). The magnitude of mandibular advancement following BSSO was 7.68±1.39 mm and 7.53±1.28, respectively, without significant difference among the groups (p= 0.68). The mean sagittal and vertical changes (relapse) at point B were significantly different between the two groups at 1-year follow-up after the osteotomy (p=0.001 and p=0.05, respectively).

Conclusion: According to the results of this study, patients with short-term MMF following BSSO for mandibular advancement benefit from significantly greater skeletal stability in the sagittal and vertical dimensions.

Background: Even though dental implants are a reliable choice for dental rehabilitation, implant failures due to various etiologies have been reported. Early implant failures account for 2 to 6% of installed implants and are reported to have a higher rate than late failures, regardless of loading time. We herein report three cases of acute sinusitis and early implant failure with implants that failed within 1 month after installation. The aim of this study was to evaluate the surface properties of early failed implants and peri-implant tissue to determine the early osseointegration pattern in acute sinusitis-related failed implants as well as the possible role of surface contamination in the failure of osseointegration.

Results: A combined histological, electron microscopy, and X-ray spectroscopy approach was used to characterize the surface of non-osseointegrated titanium implants and the surrounding biological tissues. Morphologic scanning electron microscopy revealed a heterogeneous surface and irregular osseointegration. The implant surface was covered mostly by carbon- and oxygen-rich organic matter. Energy-dispersive X-ray spectroscopy surface analysis of three implants showed the incorporation of some contaminants in both the upper and apical regions. Carbon, nitrogen, sodium, silicon, chlorine, sulfur, gold, and zirconium were detected on the surface of one or more failed implants. Fibrosis, lymphocytic, and macrophage infiltrates and a high activation of osteoclasts surrounding the bone graft particles were detected in the surrounding tissues.

Conclusions: The etiology and mechanism of early implant failure, especially in sinus-related cases, as well as the proper management interventions to minimize the rate of early implant failures, are of great concern. No matter how confident and accurate the surgeon's operation, there may be unknown errors in the whole procedure that no one knows about. Rather than errors related to the implant surface, it is expected that there were invisible problems during the evaluation of the patient's own unique sinus mucosal inflammation or the operator's own procedure. Furthermore, well-designed researches are necessary to reveal the effect of material-related factors on acute sinus complication and early implant failure.