Maxillofacial Plastic and Reconstructive Surgery最新文献

Background: The effects of unilateral submandibular gland excision on the size of the contralateral gland are not well understood, with no human studies reported to date. This study aims to investigate the impact of unilateral submandibular gland excision on the contralateral gland's size, providing insights into compensatory mechanisms and their clinical implications.

Method: This retrospective study involved patients with oral cancer who underwent unilateral submandibular gland excision and ipsilateral neck dissection at Gangneung-Wonju National University Dental Hospital between 2008 and 2023. Patients were included if they had preoperative and follow-up 3D radiological images. The contralateral submandibular gland volume was measured using 3D Slicer software on preoperative, post-operative, and follow-up radiographic data.

Results: The mean volume change of the contralateral submandibular gland was 1.35 ± 2.06 cm3, with a mean change ratio of 1.18 ± 0.24. These changes were statistically significant (p = 0.006). Other factors such as age, gender, and radiotherapy did not significantly affect the volume change ratio (p > 0.05).

Conclusion: The contralateral submandibular gland exhibits a statistically significant increase in volume following unilateral gland excision, indicating compensatory hypertrophy. This morphological adaptation should be considered in post-operative care and surgical planning for oral cancer patients to optimize outcomes.

Background: Xerostomia, or dry mouth, can be a temporary or persistent symptom resulting from various factors, such as medication use, therapeutic radiation, chemotherapy, autoimmune conditions (e.g., Sjögren's syndrome), and hormonal imbalances. Xerostomia often leads to associated mucositis, which significantly impacts patients' quality of life. The nano-bio-fusion (NBF) gingival gel, a gel-type functional toothpaste containing vitamins C, E, propolis, and herbal extracts in a nano-emulsion state, has shown potential in accelerating the healing of oral mucosal lesions.

Methods: A total of 127 patients (102 females, 25 males) with persistent xerostomia were treated from 2018 to 2023. Of these, 32 patients were treated exclusively with NBF Gel, while 95 patients received NBF Gel in combination with other medications, such as pilocarpine. The underlying causes of xerostomia included irradiation and chemotherapy (12 patients), medication (40 patients), hormonal imbalance (28 patients), and Sjögren's syndrome (47 patients). NBF Gel was applied 2-3 times daily to the tongue and oral mucosa. Treatment effectiveness was evaluated through physical examinations and a patient-reported scale ranging from 1 (no improvement) to 10 (complete improvement), focusing on the healing of mucosal lesions rather than saliva production.

Results: Both treatment groups showed significant improvements in the healing of xerostomia-associated mucositis, particularly in severe cases with visible lesions. Patients treated with NBF Gel reported improved symptoms related to mucosal health, while those who received combination therapy also experienced reduced side effects of pilocarpine due to dose reduction. The most substantial improvements were observed in patients with drug-induced and hormonally-caused xerostomia-related mucositis. No adverse side effects from NBF Gel were reported during the study.

Conclusion: NBF gingival gel proved to be beneficial in accelerating the healing of mucositis associated with xerostomia, regardless of the underlying cause, including medication use, radiotherapy, chemotherapy, hormonal imbalances, and Sjögren's syndrome. It presents a promising adjunctive treatment to improve mucosal health and quality of life for patients suffering from xerostomia-associated mucositis.

Background: Relapses following orthognathic surgery have been reported to exceed 2% to 50%, depending on multiple factors. This study aimed to analyze the stability after orthognathic surgery in patients with mandibular ramus height asymmetry through 3D reconstruction using Cone-beam CT.

Methods: This retrospective cohort study investigated patients who underwent mandibular setback surgery using bilateral sagittal split ramus osteotomy. Three-dimensional CT scans were taken at three different time points. Evaluation of the postoperative stability involved measuring changes in the x, y, and z axes as well as roll and yaw rotations of the mandible at specific landmarks (B point, mental foramen) on 3D CT scans obtained immediately after surgery and 6-12 months postoperatively. They were categorized into four groups based on bilateral mandibular height asymmetry through Asymmetry index (AI). The one-way ANOVA was implemented to compare the intergroup differences and Tukey's post hoc test was employed. Additionally, the Pearson correlation coefficient was also calculated.

Results: A total of 24 patients were included in this study. The corresponding AI, representing the degree of asymmetry in both mandibles, were calculated as Group 1 was 1.25 ± 0.64%, Group 2 was 2.89 ± 0.47%, Group 3 was 5.03 ± 0.51%, and Group 4 was 9.40 ± 1.99%. The x-axis change in Group 4 was significantly larger at 1.71 mm compared to Group 1 at 0.64 mm. The mandibular roll, Group 4 showed a statistically significant increase at 1.33° compared to Group 1 at 0.35°. And there was a significant positive correlation observed between x-axis change and AI (p = 0.019), as well as between mandibular roll and AI (p = 0.025).

Conclusion: After orthognathic surgery, stability was influenced by numerous factors, with the findings of this study suggesting that the degree of ramus height asymmetry in the mandible can be considered one contributing factor.

Background: Tumor tissues comprise cancer cells and stromal cells, and their interactions form the cancer microenvironment. Therefore, treatments targeting cells other than cancer cells are also actively being developed, and among them, treatment targeting PD-1, an immune checkpoint molecule that is important in tumor immune evasion, has also been indicated for head and neck cancer. PD-L1, a ligand of PD-1, is expressed in both tumor cells and stromal cells, and the scoring system based on the combined positivity rates of both types of cells, the combined positive score (CPS), is used for predicting treatment effect. However, much is unknown regarding the expression of PD-L1. In this study, we histopathologically examined factors controlling the expression of PD-1/PD-L1. This study included 37 patients who underwent resection surgery for tongue squamous cell carcinoma in the Department of Oral and Maxillofacial Surgery at Tokyo Dental College Suidobashi Hospital. The expression levels of PD-L1, α-SMA, and p53 were assessed by immunohistochemical staining.

Results: Seven participants had CPS ≥ 20, twenty-four participants had 1 ≤ CPS < 20, and six participants had CPS < 1. The overall positivity rate of α-SMA, a marker for cancer-associated fibroblasts (CAFs), was 27% (10/37 participants), and the positivity rates of α-SMA for the three CPS groups were 85.7% (6/7 participants), 16.7% (4/24 participants), and 0% (0/6 participants), respectively. In addition, the overall positivity rate of p53 was 37.8% (14/37 participants), and the positivity rates of p53 for the three CPS groups were 71.4% (5/7 participants), 37.5% (9/24 participants), and 0% (0/6 participants), respectively.

Conclusions: The expression of PD-L1 demonstrated an association with α-SMA and p53 positivity. In addition, compared with the expression of p53, the expression of α-SMA demonstrated a higher association with PD-L1 expression in patients with a high CPS. The abovementioned findings suggest that the interactions between CAFs, cancer cells, and immunocompetent cells may regulate the expression of PD-L1.

Background: Despite the advancement of reconstructive surgical techniques, facial defect reconstruction has been always very challenging, aesthetic satisfaction has often been difficult to achieve due to the unique characteristics and complexity of the facial tissue. There have been various options regarding reconstruction and compensation of soft tissue loss all over the body rather than the face. Regardless of whether skin grafts, local flaps, and free flaps were used in the reconstruction process, each of them has its limitations. Beginning with skin grafts results could not always be satisfactory due to contracture, color, and lack of texture Additionally, local flaps have limitations due to mobility and the availability of overlapping skin and tissue, as well as the bulkiness of the pedicle which may need a second staged surgery and lately the difficulty of the free flaps and being a major surgery.

Results: Patients ages ranged between 23 and 77 years old, with a mean age of 58.33 ± 12.47. As regards the patients' sex, 63.3% of our patients were males and 36.7% were females. Co-morbidities were found in 60% of cases (DM 23.3%, HTN 20%, HCV 3.3%, cardiac 3.3%). Most flaps were facial artery perforator flaps 53.3%, then transverse facial artery 26.7%, superficial temporal artery 10%, angular artery 6.7%, and supra-trochlear artery 3.3%. Twenty-ix cases representing 86.7% of cases went uneventful, while complications showed in 4 cases representing 13.3% of cases, 1 case (3.3%) showed venous congestion that was relieved within 24 h after 2 suture releases, another case (3.3%) showed wound dehiscence that was improved after 2 days with regular dressings, the third patient (3.3%) had recurrence after 4 months that was treated by excision and grafting, while last patient (3.3%) had inadequate excision that was treated by radiotherapy. No bleeding or infection occurred. Also, we observed no correlation between flap length and complications. As regards the functional point of view, all patients showed no functional impairment at the donor site, and only one case showed functional impairment at the recipient site. As regards patient satisfaction, all 30 patients achieved positive satisfaction scores using the Likert scale, 18 cases were satisfied, and 12 cases were very satisfied.

Conclusion: The use of perforator-based flaps can provide a more effective and aesthetically pleasing solution for the reconstruction of small to moderate facial defects, provided that a reliable Perforator is accurately identified and executed by an experienced surgeon.

Introduction: Orthognathic surgery (OGS) is a highly sophisticated surgical technique that aims to repair a variety of skeletal and dental abnormalities, including misaligned jaws and teeth. It requires precise preoperative preparation and advanced surgical skills, which are typically learned through years of practical experience in operating rooms or laboratory-based surgical training facilities utilizing cadavers or models. The traditional physical hands-on method of surgical training is still used at OGS. However, this method requires a longer time of preparation. Currently, mixed reality (MR)-a combination of virtual reality and augmented reality technology-is an innovation of OGS. The present study aimed to present a comprehensive review of studies that assessed the advantages of utilizing mixed reality technology in OGS.

Methods: A modified Population, Intervention, Comparison, Outcome strategy was performed using a combination of electronic (PubMed, Cochrane, Embase) and manual searches between 2013 and 2023 exploring mixed reality (MR) technology in OGS in the last 10 years. The inclusion criteria were limited to the patient and study model focusing on the clinical application of MR and the associated field of OGS.

Result: The initial search indicated 1731 studies, of which 17 studies were included for analysis. The main results indicated that the use of MR technology in OGS led to high accuracy and time reduction as primary outcomes and cost-effectiveness and skill improvement as secondary outcomes. The review firmly concluded that MR technology exhibited a positive impact on students, trainees, and oromaxillofacial surgeons. However, due to the heterogeneity of the included studies, meta-analyses could not be performed. Collectively, these findings provide strong evidence for the advantages of MR technology in orthognathic surgery.

Conclusion: MR technology significantly improves OGS planning efficiency by providing pre-surgical information and serving as an intraoperative navigation tool, reducing surgical time without compromising outcomes. Virtual training using MR technology exerts a positive impact on knowledge and skill improvement for OGS. This innovative technology will revolutionize the healthcare system and enhance patient care.

Background: Many studies have been reported on tracheostomy to prevent upper airway obstruction after surgery. Among these, the scoring system proposed by Cameron et al. quantifies various factors that influence postoperative respiratory failure. This system provides a basis for surgeons to decide whether to perform an elective tracheostomy. In this study, the authors applied the Cameron scoring system retrospectively to patients undergoing severe oral cancer surgery to reevaluate the indications for elective tracheostomy and to investigate its clinical efficacy in airway management. In this study, a sample of 20 patients who underwent oral cancer surgery was selected and divided into two groups: 10 underwent tracheostomy and 10 did not. The Cameron scoring scores for each patient were extracted, to verify whether elective tracheostomy was performed in accordance with the threshold scores. Differences in scores and significant clinical impact factors between the two groups were analyzed and compared.

Result: The 10 patients who underwent tracheostomy had an average Cameron score of 6.4, all scoring above the recommended threshold of 5 for tracheostomy. For the 10 patients who did not undergo tracheostomy, the average score was 2.5, with 8 out of these 10 patients scoring below 5. Significant clinical impact factors observed included the location and size of the tumor, the performance of mandibulectomy and neck dissection, and the type of reconstruction surgery.

Conclusion: In planning surgery for oral cancer patients, it is essential to consider the use of elective tracheostomy based on preoperative assessment of the risk of postoperative airway obstruction using tools like the Cameron scoring system, and patients' condition. Research confirms that elective tracheostomy effectively enhances airway management in patients with severe oral cancer.

Background: Based on a three-dimensional (3D) orthognathic simulation, this technical report introduces a method for augmentation genioplasty using a proximal bone fragment of the mandible, which is typically discarded in intraoral vertical ramus osteotomy (IVRO).

Results: A 43-year-old female patient diagnosed with Class III malocclusion, presenting with a protruding mandible and long facial height, underwent surgical treatment. The surgical plan involved mandibular setback position using IVRO and augmentation genioplasty. The 3D orthognathic surgery including augmentation genioplasty simulation was performed. An excessively elongated proximal segment was sectioned following IVRO. The inferior part of the sectioned proximal bone fragment of the mandible was positioned to align with the requirements of advancement genioplasty. After ensuring that the placement of the fragment matched that of the simulated surgery, each bone fragment was fixed. At 1.5 years post-surgery, the grafted bone on the augmentation genioplasty was well maintained, with slight bone resorption.

Conclusions: Augmentation genioplasty using the proximal bone fragment of the mandible, which is typically discarded in IVRO, reduces the surgical complications associated with chin osteotomy. When a secondary genioplasty is required, genioplasty with osteotomy, movement of the cut bone fragments, partial bone-shaving osteotomy, and additional bone grafting are viable options.

Background: Orthodontic and surgical technical advances in recent years have resulted in treatment opportunities for a whole range of craniofacial skeletal disorders either in the adolescent or adult patient. In the growing child, these can include myofunctional orthodontic appliance therapy or distraction osteogenesis procedures, while in the adult, the mainstay approach revolves around orthognathic surgery. The literature agrees that for a change in craniofacial morphology to remain stable, the muscles acting upon the facial skeleton must be capable of adaptation in their structure and, therefore, their function. Failure of the muscles to adapt to the change in their length or orientation will place undesirable forces on the muscle attachments leading to potential instability of the skeleton. Adaptation can occur through various processes including those within the neuromuscular feedback mechanism, through changes within muscle structure or through altered muscle physiology, and through changes at the muscle/bone interface. It is now accepted that because there is no single method of assessing masticatory function, several measures should be taken, and whenever possible, simultaneously.

Methods: This investigation was designed to apply several, newly developed and more sophisticated methods of measuring muscle structure and function to a situation where adaptation of muscle is pivotal to the success of a therapeutic approach. Patients attending the combined orthodontic/orthognathic surgery clinic at the Clitrofa - Centro Médico, Dentário e Cirúrgico, in Trofa, Portugal, were screened. Ten patients scheduled for a bimaxillary osteotomy involving a combination of maxillary Le Fort I impaction procedure coupled with a sagittal split advancement of the mandible were selected to form the study group. The patients have MRI of the masseter muscle to evaluate the masseter muscle volume and fibre orientation changes. This exam was taken before surgery (T0), 6 to 12 months after surgery (T1), and 3 years after surgery (T2), by two independent observers, according to the protocol jointly developed between the Eastman Dental Institute - University of London and the MRI Centre - Department of Radiology at John Radcliffe Hospital - University of Oxford.

Results: Significant differences (p < 0.05) have been identified between Time 0 (pre-op) and Time 1 (6-12 months post-op) regarding the masseter area (mm²). The differences against Time 0 (pre-op) seem to disappear at Time 2 (3 years post-op).

Conclusions: MRI therefore seems to be a valid tool for measuring differences in the masseter muscle area and volume associated with high-severity occlusal deformities, although showing not to be as efficient in detecting the same differences in cases of low-severity occlusal deformities.