Application of 3D technology for the design of a guidewire for deep cervicofacial collections percutaneous management.

Background: This study aims to present a case of deep cervicofacial abscesses and demonstrate the efficacy of CT-guided drainage with a custom-designed puncture guide in a challenging anatomical location. The use of this type of guide is an innovative technique since CAD-CAM technology has not been used for this type of application until now. Material and Methods: A 76-year-old man with persistent facial swelling and trismus underwent surgical drainage initially, but symptoms persisted. A CT-guided transcutaneous approach was planned using a custom-designed positioning guide created with "in-house" 3D technology. The guide was fabricated using Surgical Guide resin, and the patient underwent successful CT-guided drainage. Results: The intervention facilitated precise drainage without damaging critical anatomical structures. The patient exhibited prompt clinical improvement, shortened hospitalization, and favorable aesthetic outcomes. Conclusions: CT-guided drainage, particularly when combined with a custom puncture guide, offers a less invasive alternative for challenging cervicofacial abscesses. This approach proves valuable in reducing procedure duration, minimizing soft tissue trauma, and enhancing preoperative planning, making it especially beneficial for patients with high anesthetic risk or complex anatomical considerations. Key words:Cervical abscess, 3D technology, drainage guide, percutaneous puncture.

Venous malformation differential diagnosis with an odontogenic abscess on a pediatric patient. Case report and review of the literature.

Venous malformations (VMs) are aberrant venous vessel angiogenesis present at birth. However, they can become apparent later in life, debuting in early childhood. This poses a clinical quest for surgeons, dentists, and pediatricians, as they might appear as a compressible mass in the head and neck region, not uncommonly mistaking them for odontogenic abscesses or other soft tissue tumors. The differential diagnosis can be challenging and imaging techniques are often needed. Ultrasounds are extremely useful initially as other diagnostic tools can be potentially harmful in the context of a VM. MRI is key as it provides accurate extension and location information, and allows to plan invasive treatment alternatives if the patient requires it. In this article, we present the case of a 6-year-old girl who was treated by mistake for an infection upon the diagnosis of an incipient odontogenic abscess instead of a venous malformation, and a literature review on VMs. Key words:Venous malformation, odontogenic abscess, differential diagnosis.

Surface scanned 3D designed customized chinstrap for the treatment of intraoral dehiscence in polytraumatized patient. Technical note.

The advent of 3D surgical technology has revolutionized personalized medicine, enabling the development of tailored solutions for individual patients. This technical note presents the application of 3D technology in designing a customized chin guard using flexible 3D resin. The process involves surface scanning the lower facial region of a polytraumatized patient with a structured-light surface 3D scanner, generating a detailed point cloud. The acquired data undergoes meticulous processing within an specific professional software, including erasing unwanted portions, aligning frames, and mesh consolidation. Subsequently, the mesh is exported as an STL file and further refined using a 3D mesh management software. A customized chin support is designed for the specific patient's needs, exported in STL format, and 3D printed using a stereolithography (SLA) printer with Flexible 80A resin. Post-printing procedures involve washing and curing to ensure biocompatibility and optimal mechanical characteristics. The resultant customized chin guard, attached to elastic support straps, offers a precise fit to the patient's anatomy, enhancing comfort and allowing for extended wear. This innovative approach addresses the challenge of surgical intraoral wound dehiscence in a polytraumatized patient, showcasing the potential of 3D technology in personalized medical solutions for complex cases. Key words:Surface scanner, 3D surgery, customized surgery, chinstrap.

Virtual Surgical Planning for Temporomandibular Joint Reconstruction with Stock TMJ Prostheses: Pilot Study.

The temporomandibular joint (TMJ) is one of the most complex joints in the human anatomy. In advanced degenerative stages, conservative or minimally invasive surgical therapies have failed to restore joint function, and joint replacement with prostheses has been required. Stock prostheses, compared to custom-made prostheses, are much less expensive and require less pre-operative preparation time. Four patients followed for years for temporomandibular dysfunction and previously operated on by arthroscopy or open joint surgery that have been reconstructed with stock TMJ prostheses (STMJP) through virtual surgical planning (VSP) and an STL model with surgical and positioning guides were included. The median follow-up was 15 months; the median number of previous TMJ surgeries was 2. The mean preoperative MIO was 24.6 mm and at longest follow-up was 36.4 mm. The median preoperative TMJ pain score was 8, and the median postoperative TMJ pain was 3. All patients have improved their mandibular function with a clear improvement of their initial situation. In conclusion, we believe that stock TMJ prostheses with virtual surgical planning and surgical guides are a good alternative for TMJ reconstruction at the present time. Nonetheless, prospective and randomized trials are required with long-term follow up to assess their performance and safety.

3D designed in-house positioning and cutting guide system for genioplasty surgery. Technical note and case report.

Advances in 3D printing technology have the potential to significantly improve the workflow of maxillofacial surgical planning. In-house fabricated custom positioning and cutting guides allow for intraoperative reproduction of pre-planned osteotomy cuts, which can result in greater surgical accuracy and patient safety while maintaining an acceptable cost-effectiveness ratio. The design and creation of the customized surgical guides is performed in our hospital fab lab, which allows time savings, from an average of 10 days to just 24 hours, and a cost reduction of more than 90%. The process begins with the import of the pre-surgical facial CT scan into 3D software that allows to perform the surgical cuts virtually and the manipulation of the segments. Once the virtual planning of the surgery has been performed, the next step is the creation of the cutting and positioning guides. The final step is the printing of the guides in surgical resin and their sterilization. In addition, post-surgical models can be 3D printed to pre-mold the plates on them, which saves surgical time. The mentoplasty surgery is a simple example of how 3D surgery can be applied to maxillofacial surgery in an efficient way obtaining all the advantages of customized surgery with a limited investment in time and resources. Key words:3Dsurgery, customized, personalized medicine, genioplasty, surgical guides, in house.

Depth of Invasion: Influence of the Latest TNM Classification on the Prognosis of Clinical Early Stages of Oral Tongue Squamous Cell Carcinoma and Its Association with Other Histological Risk Factors.

BACKGROUND: The American Joint Committee on Cancer (AJCC), in its 8th edition, introduces modifications to the previous TNM classification, incorporating tumour depth of invasion (DOI). The aim of this research is to analyse the prognosis (in terms of disease-free survival and overall survival) of clinical early stage (I and II) squamous cell carcinomas of the oral tongue according to the DOI levels established by the AJCC in its latest TNM classification to assess changes to the T category and global staging system and to evaluate the association between DOI and other histological risk factors. METHODS: A retrospective longitudinal observational study of a series of cases was designed. All patients were treated with upfront surgery at our institution between 2010 and 2019. The variables of interest were defined and classified into four groups: demographic, clinical, histological and evolutive control. Univariate and multivariate analyses were carried out and survival functions were calculated using the Kaplan-Meier method. Statistical significance was established for p values below 0.05. RESULTS: Sixty-one patients were included. The average follow-up time was 47.42 months. Fifteen patients presented a loco-regional relapse (24.59%) and five developed distant disease (8.19%). Twelve patients died (19.67%). Statistically significant differences were observed, with respect to disease-free survival (p = 0.043), but not with respect to overall survival (p = 0.139). A total of 49.1% of the sample upstaged their T category and 29.5% underwent modifications of their global stage. The analysis of the relationship between DOI with other histological variables showed a significant association with the presence of pathological cervical nodes (p = 0.012), perineural invasion (p = 0.004) and tumour differentiation grade (p = 0.034). Multivariate analysis showed association between depth of invasion and perineural invasion. CONCLUSIONS: Depth of invasion is a histological risk factor in early clinical stages of oral tongue squamous cell carcinoma. Depth of invasion impacts negatively on patient prognosis, is capable per se of modifying the T category and the global tumour staging, and is associated with the presence of cervical metastatic disease, perineural invasion and tumoural differentiation grade.

HPV infection in oral cancer, our experience: prevalence, clinical implications, and current vaccination program in Spain.

Background: Oral cancer is the 11th most common type of cancer in the world, with established major risk factors as tobacco and alcohol, and recently included high-risk human papillomavirus types 16 and 18. HPV types 16 and 18 are the etiologic agents of cervical cancers and a proportion of oropharyngeal cancers. However, the picture of HPV and the clinical implications of oral cancers are not clear with most reports combining oral cancer data with head and neck cancers. It has been confirmed as a favorable prognostic factor in oropharyngeal cancer. However, the prognostic value of HPV in oral squamous cell carcinoma is still unclear. Material and Methods: The main objective of this article is to present the evidence encountered following a bibliographical review of recent publications specifically related to oral cancer and its differences from oropharyngeal cancer. The secondary goals are to present the findings of a five-year retrospective observational study of the prevalence of HPV infection in oral cancer patients treated by the Oral and Maxillofacial Surgery Department at La Paz University Hospital (Madrid, Spain), and finally, we to evaluate and compare our country's HPV prevention program in comparison to other European countries. Results: According to the review of the literature, HPV positive oral squamous cell carcinoma is associated with significantly decreased overall survival and distant control. Bibliographic review suggest HPV infection can be used as a negative prognostic factor in oral squamous cell carcinoma. Conclusions: As regards diagnostic testing for HPV, it should be extended to as many cases of oral cavity squamous cell carcinoma as possible, especially in those with risk factors. The current vaccination program in Spain does not have adequate coverage and is significantly under the level of other European Union countries; it should be expanded and catch-up strategies should be included. Key words:HPV, OSSC, Papillomavirus, oral carcinoma, prevention.

Use of surgical bone cement to increase the projection of the nasomaxillary buttress in a case of orthognathic surgery. Technical note.

The soft tissue outcome of the projection at the level of the nasomaxillary buttress is difficult to manage in cases of severe hypoprojection, being orthognathic surgery resolutive at the occlusal level but sometimes insufficient at the level of esthetic outcome. The literature describes the use of alloplastic prostheses and autologous bone grafts, but there are few documented cases of the use of premolded surgical cement for this purpose. The main advantage of the use of bone cement over the alternatives described is its ability to be premolded for customization, low cost, easy availability, speed of preparation and minimal comorbidity. This technical note describes the surgical steps and outcome of the use of surgical bone cement for projection augmentation at this level, including notes on preparation, premolding and fixation. Key words:Orthognathic surgery, maxillary surgery, surgical bone cement, nasomaxillary buttress.

Genetic Profile of Arteriovenous Anomalies of the Head and Neck: Implications in Progression and Therapeutic Approaches.

BACKGROUND: Arteriovenous Malformations (AVMs) are complex vascular anomalies that are usually sporadic and can have a variable clinical course. Treatment of AVMs can lead to severe sequeale and require thorough decision-making. There is a lack of standardized treatment protocols showing a growing need for pharmacological targeted therapies, specially in the most severe cases where surgery may not be feasible. Current knowledge in molecular pathways and genetic diagnosis have shed light in the pathophysiology of AVMs, opening possibilities for personalized treatment strategies. METHODS: We performed a retrospective review of patients with head and neck AVMs treated in our department between 2003 and 2021 and performed a complete physical examination and imaging with ultrasound and angio-CT or MRI. Patients underwent genetic testing on AVMs' tissue samples and/or peripheral blood samples. Patients were grouped according to the genetic variant and a correlation between phenotype and genotype was studied. RESULTS: 22 patients with head and neck AVMs were included. We found eight patients with varians in MAP2K1, four patients with pathogenic variants in KRAS, six patients with pathogenic variants in RASA1, one patient with a pathogenic variant in BRAF, one patient with a pathogenic variant in NF1, another patient with a pathogenic variant in CELSR1 and one patient with pathogenic variants in PIK3CA and GNA14. Patients with MAP2K1 variants were the biggest group, with a moderate clinical course. Patients with KRAS mutations showed the most aggressive clinical course and a high rate of recurrence and osteolysis. Patients with RASA1 variants showed a characteristic phenotype with an ipsilateral capillary malformation in the neck. CONCLUSION: We found a correlation between genotype and phenotype in this group of patients. The genetic diagnosis of AVMs is recommended in order to stablish a personalized treatment strategy. Targeted therapies are currently being investigated with promising results and may be recommended in addition to conventional surgical or embolization procedures, specially in the most complex cases. LEVEL OF EVIDENCE: Level IV.

Peripheral odontogenic keratocyst. A Case report.

Odontogenic keratocysts (OKCs) are benign cysts arising from the dental lamina and its remnants. They are most commonly located in the posterior body and the ramus of the mandible. The diagnosis of peripheral OKCs (other than intraosseous) are extremely rare and the current literature is limited. The most common location is the gingiva, but mucosal, epidermal, and even intramuscular sites have also been described. Currently 15 cases have been described. The origin and nature of peripheral OKC still remains controversial. The differential diagnosis includes gingival cyst, mucoceles and epidermoid cyst. Soft tissue OKCs have a lower rate of recurrences; 12,5% vs. 62% in intraosseus OKCs. We report a case of a 58-year-old woman with a peripheral OKC, located in the left masticatory space. We performed a review of the existing literature on peripheral odontogenic keratocysts. Key words:Odontogenic keratocysts (OKCs), peripheral keratocyst, mandibular cyst.

Reconstrucción maxilar con un implante subperióstico en un caso de atrofia severa. De la planificación a la rehabilitación siguiendo un protocolo totalmente digital. A propósito o clínico y revisión bibliográfica / Maxillary reconstruction with a subperiosteal implant in a case of severe atrophy. From planning to rehabilitation following a fully digital protocol. A clinical case report and literature review

Introducción: Los implantes subperiósticos personalizados de titanio, diseñadosa partir de un software de planificación yfabricación, constituyen una alternativaen la rehabilitación de atrofias severasen los maxilares, evitando cirugías de reconstrucción óseas y el de partes blandasmás complejas y disminuyendo los tiempos de cicatrización. El objetivo de este trabajo es presentar la rehabilitación enun caso clínico con una atrofia severa enmaxilar superior, utilizando una estructuracon implantes subperiósticos, medianteun protocolo digital.Descripción del caso: Se diseñó unaestructura subperióstica de titanio sinterizada con seis conexiones transepitelialesque fueron rehabilitadas con una prótesisfija inmediata implantosoportada fabricada en PMMA. Dos meses después, serealizó una estructura sinterizada en cromo-cobalto con bases mecanizadas recubierta con dientes de resina acrílica comorestauración final. En el seguimiento a unaño, el caso permanece estable.Conclusiones: Hoy en día, la rehabilitación con implantes subperiósticos constituye una herramienta alternativa en casosde cirugías complejas con grandes atrofias con la posibilidad, además, de realizar una carga inmediata. (AU)

Introduction: Customized subperiosteal titanium implants, designed from planning and fabrication software, constitute analternative in the rehabilitation of severe maxillary atrophy, avoiding more complex bone and soft reconstruction surgeries and reducing healing times. The aim of this article is to present the rehabilitation in a clinical case with severe atrophy in the upper jaw, using a structure with subperiosteal implants, by means of a digital protocol.Clinical Case: A subperiosteal sintered titanium structure was fabricated with six transepithelial connections that were rehabilitated with an immediate implant-supported fixed prosthesis made of PMMA. Two months later, a sintered Chromium-Cobalt framework with machined bases covered with acrylic resin teeth was fabricated as the final restoration. At one year follow-up, the case remains stable. Conclusions: Nowadays, rehabilitatin with subperiosteal implants is an alternative tool in cases of complex surgeries with large atrophies with the possibility of immediate loading. (AU)

Buccal cheek mucosa solitary fibrous tumor. Case report.

Solitary fibrous tumor (STF) is a mesenchymal tumor that mainly appears in the pleura. Its presence in the oral cavity is very uncommon, being the buccal mucosa the most frequent location. Imaging cannot distinguish this entity between other types of tumors, being histological and immunohistochemical studies essential for its diagnosis. Immunohistochemical stains typically show positive results for CD34, Bcl2, and CD99. Surgical removal with wide margins is the gold standard treatment, requiring a close follow up due to recurrence risk. We present a case report of a solitary fibrous tumor located in the buccal cheek mucosa and the surgical approach. Key words:Solitary fibrous tumor, Buccal mucosa, Intraoral, Immunohistochemical markers.

Nota técnica: planificación virtual 3D en el tratamiento de fractura doble en mandíbula atrófica / Technical note: 3D virtual planning for atrophic mandible double fracture reduction

El uso de la planificación virtual ha demostrado en varios estudios una mayor predictibilidad de los resultados quirúrgicos, así como una reducción del tiempo quirúrgico y la posibilidad de comparar nuestros resultados con los esperados mediante una comparación con un TC postoperatorio. En esta nota técnica se describe cómo planificar de forma virtual la cirugía mediante tecnología 3D “in house” de fracturas en mandíbulas atróficas usando un software de uso libre. (AU)

The use of virtual planning has demonstrated in several studies greater predictability of surgical results, as well as a reduction in surgical time. In addition, we have the possibility to compare our results with the planning through a comparison with a postoperative CT. This technical note aims to describe how to plan surgery for fractures in atrophic mandibles using pre-surgical 3D technology and a free software. (AU)

A Quantitative and Qualitative Clinical Validation of Soft Tissue Simulation for Orthognathic Surgery Planning.

The purpose of this study was to perform a quantitative and qualitative validation of a soft tissue simulation pipeline for orthognathic surgery planning, necessary for clinical use. Simulation results were retrospectively obtained in 10 patients who underwent orthognathic surgery. Quantitatively, error was measured at 9 anatomical landmarks for each patient and different types of comparative analysis were performed considering two mesh resolutions, clinically accepted error, simulation time and error measured by means of percentage of the whole surface. Qualitatively, evaluation and binary questions were asked to two surgeons, both before and after seeing the actual surgical outcome, and their answers were compared. Finally, the quantitative and qualitative results were compared to check if these two types of validation are correlated. The quantitative results were accurate, with greater errors corresponding to gonions and lower lip. Qualitatively, surgeons answered similarly mostly and their evaluations improved when seeing the actual outcome of the surgery. The quantitative validation was not correlated to the qualitative validation. In this study, quantitative and qualitative validations were performed and compared, and the need to carry out both types of analysis in validation studies of soft tissue simulation software for orthognathic surgery planning was proved.

Virtual Surgical Planning and Customized Subperiosteal Titanium Maxillary Implant (CSTMI) for Three Dimensional Reconstruction and Dental Implants of Maxillary Defects after Oncological Resection: Case Series.

Maxillectomies cause malocclusion, masticatory disorders, swallowing disorders and poor nasolabial projection, with consequent esthetic and functional sequelae. Reconstruction can be achieved with conventional approaches, such as closure of the maxillary defect by microvascular free flap surgery or prosthetic obturation. Four patients with segmental maxillary defects that had been reconstructed with customized subperiosteal titanium maxillary implants (CSTMI) through virtual surgical planning (VSP), STL models and CAD/CAM titanium mesh were included. The smallest maxillary defect was 4.1 cm and the largest defect was 9.6 cm, with an average of 7.1 cm. The reconstructed maxillary vertical dimension ranged from 9.3 mm to 17.4 mm, with a mean of 13.17 mm. The transverse dimension of the maxilla at the crestal level was attempted to be reconstructed based on the pre-excision CT scan, and these measurements ranged from 6.5 mm in the premaxilla area to 14.6 mm at the posterior level. All patients were rehabilitated with a fixed prosthesis on subperiosteal implants with good esthetic and functional results. In conclusion, we believe that customized subperiosteal titanium maxillary implants (CSTMI) are a safe alternative for maxillary defects reconstruction, allowing for simultaneous dental rehabilitation while restoring midface projection. Nonetheless, prospective and randomized trials are required with long-term follow-up, to assess its long-term performance and safety.

New Technologies for Personalized Medicine in Head and Neck Oncologic and Reconstructive Surgery.

The search for standardized protocols has been a constant concern in Head and Neck Reconstructive Surgery [...].

Microtia Ear Reconstruction with Patient-Specific 3D Models-A Segmentation Protocol.

(1) Background: In recent years, three-dimensional (3D) templates have replaced traditional two-dimensional (2D) templates as visual guides during intra-operative carving of the autogenous cartilage framework in microtia reconstruction. This study aims to introduce a protocol of the fabrication of patient-specific, 3D printed and sterilizable auricular models for autogenous auricular reconstruction. (2) Methods: The patient's unaffected ear was captured with a high-resolution surface 3D scan (Artec Eva) and post-processed in order to obtain a clean surface model (STL format). In the next step, the ear was digitally mirrored, segmented and separated into its component auricle parts for reconstruction. It was disassembled into helix, antihelix, tragus and base and a physical model was 3D printed for each part. Following this segmentation, the cartilage was carved in the operating room, based on the models. (3) Results: This segmentation technique facilitates the modeling and carving of the scaffold, with adequate height, depth, width and thickness. This reduces both the surgical time and the amount of costal cartilage used. (4) Conclusions: This segmentation technique uses surface scanning and 3D printing to produce sterilizable and patient-specific 3D templates.