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Lateral, Hemimandibular, Anterior.
No full textMaintaining projection and support of the lower face and planning for endosseous dental implant positioning require bony reconstruction of the mandible when a major defect occurred. To completely restore the anterior mandible, it is necessary to overcome the limited height of the fibula compared to the native symphyseal and parasymphyseal region; adequate bone height is a precondition for dental implant planning. Intraoral tissue reconstruction and a myofascial lining can also be performed with myofascial fibula flap or with simple/folded skin island of fibula flap. For the largest defects, a double flap (fibula osteocutaneous flap externally, radial forearm fasciocutaneous or vertical rectus abdominis myocutaneous intraorally) may be required. We briefly describe the mandibular reconstructive principles through fibula flap related to specific defects, referring to the classification proposed by Cordeiro et al
Technique
No full textThe aim of maxillary or mandibular reconstruction must be to restore not only aesthetics but also complete oral function. Cortical bone thickness, height, and bicortical structure of the fibula shaft is ideal for long-term implant-borne prosthetic rehabilitation. Fibular cortical thickness is superior with respect to the iliac crest or the scapula crest. The efficacy of dental implants placed into free fibula flaps for orofacial reconstruction has been thoroughly proved. Some authors have reported the possibility of inserting implants into the free fibula flap during the primary reconstruction. The major disadvantage of immediate implant insertion concerns the high possibility of misalignment of the fixtures. The use of oral implants in irradiated tissue is not considered to be contraindicated. The timing of the implantation procedure, with regard to the effects of irradiation on the jawbone, remains inconclusive for lack of scientific evidence. Typically, dental implants are placed 6–12 months after radiation therapy. The fibula flap is commonly harvested as osteocutaneous flap, so that a skin paddle is harvested with the fibula bone graft. The skin paddle is bulky, much thicker than the gingiva, not fixed to the bone by the periosteum, and not keratinized. Several techniques are used in soft-tissue management after a fibula vascularized graft, such as skin graft, mucosa graft, or biological membranes
Linfadenectomia sovraomoioidea.
Full text linkLo svuotamento linfonodale sovra-omoioideo è la dissezione laterocervicale selettiva più frequentemente eseguita in caso di carcinoma del cavo orale. Con il termine “svuotamento linfonodale selettivo” si intende l’asportazione dei pacchetti linfonodali a maggior rischio di metastasi, con la preservazione di uno o più livelli linfonodali di solito rimossi durante uno svuotamento radicale. In particolar modo lo svuotamento sovraomoioideo prevede la dissezione del I-II-III livello linfonodale (ovvero al di sopra, cranialmente, rispetto al muscolo omoioideo). La possibilità di eseguire dissezioni selettive del collo si basa sul fatto che il drenaggio linfatico delle mucose del cavo orale, in pazienti con carcinoma a cellule squamose precedentemente non trattati, segue percorsi relativamente costanti e di conseguenza le metastasi linfonodali presentano un pattern di diffusione relativamente prevedibile in base alla localizzazione del tumore primitivo. Gli studi anatomici di Rouvière, Fish e Sigel (e successivamente Shah) hanno concluso che i tumori della cavità orale metastatizzano più frequentemente ai linfonodi del collo del I, II, e III livello, mentre i tumori dell’orofaringe, ipofaringe, laringe metastatizzano più frequentemente al II, III, e IV livello. Il trattamento chirurgico delle metastasi linfonodali è stato proposto ed eseguito in origine da Von Albrecht nel 1875, ai primordi della chirurgia laringea, con la sola asportazione dei linfonodi metastatici; Gluck e Sorensen asportavano anche il muscolo sternocleidomastoideo, la giugulare interna e, talvolta, la carotide. Crile nel 1898 introdusse lo svuotamento linfonodale sistematico in monoblocco con la laringectomia, dimostrando che nella sua casistica i malati così trattati sopravvivevano mediamente quattro volte di più di quelli trattati con semplice laringectomia. In seguito, circa 70 anni dopo, Suarez e Bocca iniziarono a conservare il nervo spinale accessorio, la vena giugulare interna e il muscolo sternocleidomastoideo in caso di tumori della laringe e ipofaringee con collo clinicamente negativo per localizzazioni metastatiche linfonodali. L’origine dello svuotamento selettivo, invece, non è del tutto chiara. Molti chirurghi hanno usato questo tipo di procedura per decadi senza descriverla formalmente. Per esempio, Kocher eseguiva un’asportazione parziale dei linfonodi nei pazienti con carcinoma del cavo orale e collo N0 già alla fine del diciannovesimo secolo. Con il tempo si diffuse una procedura detta “svuotamento sovraioideo” (cioè del I livello) nei casi di linfoadenopatie occulte associate ai carcinomi soprattutto del labbro. In seguito, nel 1972, Lindberg ha dimostrato che i livelli più frequentemente coinvolti in pazienti con carcinoma del cavo orale sono in genere il II e il III; nei carcinomi del pavimento della bocca e della lingua mobile il livello più frequentemente coinvolto è, invece, il I. Più tardi Byers propose i termini “anteriore” e “sovraomoioideo” per indicare le dissezioni parziali, ma solo nel 1991 si iniziò ad usare il termine selettivo per descrivere le resezioni linfonodali limitate (Academy’s Committee for Head and Neck Surgery and Oncology). In generale lo svuotamento linfonodale laterocervicale del collo può essere eseguito secondo due diversi tempi rispetto al momento dell’asportazione del tumore primario: 1) in contemporanea all’asportazione del tumore primario ed in assenza di evidenza clinica e radiologica di metastasi linfonodali laterocervicali, ovvero in stadio cN0, al fine di eradicare eventuali metastasi occulte: viene definito svuotamento elettivo o elective neck dissection. 2) successivamente all‘intervento sul tumore primario, al manifestarsi clinico o radiologico delle metastasi linfonodali laterocervicali: viene definito svuotamento terapeutico o therapeutic neck dissection. Lo svuotamento linfonodale elettivo (cN0) è abitualmente di tipo selettivo. Lo svuotamento selettivo del collo per il carcinoma del cavo orale comprende i livelli I-III ed è altrimenti denominato svuotamento linfonodale laterocervicale sovra-omoioideo. La “depth of invasion” (DOI) è ad oggi il miglior fattore per ipotizzare la presenza di metastasi linfonodali occulte laterocervicali e quindi decidere se attuare uno svuotamento linfonodale laterocervicale elettivo (cN0) o terapeutico (al manifestarsi delle metastasi linfonodali cN+). Per carcinomi con una DOI maggiore ai 4mm, si deve programmare uno svuotamento linfonodale elettivo (NCCN Guidelines, 2018). Studi randomizzati hanno dimostrato la superiore efficacia in termini di sopravvivenza dello svuotamento linfonodale elettivo in pazienti affetti da carcinomi del cavo orale cN0, quando la profondità d’infiltrazione (DOI) è superiore ai 3 mm. Quando la DOI è compresa tra 2 e 4mm si deve valutare e soppesare quando sia attuabile l’alternativa di un follow-up stringente ed accurato, secondo le specifiche condizioni socio-sanitarie del paziente in esame. In caso di dubbia aderenza al follow-up clinico-strumentale, consigliamo di effettuare uno svuotamento elettivo sovraomoioideo. In conclusione, lo svuotamento selettivo sovra-omoioideo del collo è attualmente indicato nei pazienti con carcinoma squamoso del cavo orale senza evidenza clinica o radiologica di coinvolgimento linfonodale(cN0), da attuarsi in unico tempo con l’asportazione radicale del tumore primario
Evolution in Indication
No full textSince the introduction of reconstructive technique using the fibula flap, the indications for use of this graft have evolved. The fibula graft may provide skin islands, up to 25 cm and 14 cm wide, suitable for reconstruction of associated soft tissue defects. The dual endosteal and periosteal blood supply ensures bony viability despite multiple osteotomies. Hidalgo in 1989 described the first lower jaw reconstruction with a fibular flap, using osteotomies to mimic the shape of the mandible after oncological or traumatic defects. Multiple skin islands can be harvested with the fibula graft providing an osteomyocutaneous flap, including those based on septocutaneous as well as on musculocutaneous peroneal perforators. This graft provides convenient tissue for simultaneous reconstruction of bony and soft tissue defects inside as well as outside the oral cavity, bringing viable tissue to a mostly irradiated and contaminated field, with the lowest complication rate among osteocutaneous flaps. Soleus muscle connected to motor branches at the recipient site is described to restore the motor function or by using the sural cutaneous nerve together with a skin island for restoring sensation. Flap combinations were performed by anastomosing a second free flap to the distal peroneal artery and vein, which do not significantly reduce in caliber and thus can also serve at the recipient site. The use of free vascularized fibula has become the gold standard for mandibular and maxillary extensive defects
Assessment
No full textIn order to achieve an adequate oral rehabilitation after reconstruction of the jaw, a consistent prosthetic treatment is necessary. The main determinants of implant stability are the mechanical properties of the bone tissue at the implant site, and how the contact between the implant neck and the cortical bone plate is achieved. If we presume a correct surgical technique and a good implant design, the bone density determines the primary implant stability at the time of surgery. A stable implant can exhibit different degrees of displacement or resistance to load, which corresponds to varying degrees of stability. Conversely, a failed implant shows clinical mobility on the macroscale, as the implant is surrounded by a fibrous scar tissue. An increasing degree of micro-mobility is present until clinical failure of the implant. This suggests that techniques to measure and to monitor implant micro-motion/stability could give the clinician the opportunity to optimize implant treatment. Insertion torque, Periotest, and resonance frequency analysis are suitable to measure primary implant stability. Nevertheless, the resonance frequency analysis is the only method that can detect variations in different bone densities, which may be measured even during the follow-up of the implant
Treating head and neck venous malformations with cold helium plasma electrosurgical device: A 17 patients case series
Full text linkVenous malformations (VMs) are some of the most common vascular malformations. Their treatment varies from laser to sclerotherapy and surgery. For many years, radiofrequency and argon plasma devices have been used on soft tissues VMs. However, their use has been limited because of high thermal impact of nearby structures. The here described cold-helium plasma electrosurgical device carries intrinsic bio-technical advantages, as the helium plasma beam manages to move towards tissues with less impedance, such as VM vessels. The primary objective of this study was to assess if J-Plasma® could be effective on treating the superficial portion of VMs, in a single or multimodal approach. From January 2022 to January 2024, 17 patients affected by head and neck VM involving mucosa or skin were treated using J-Plasma®, in addition to sclerotherapy. More than 1 session was needed in all but 1 patient. All patients showed a progressive shrinkage of the venous chambers and thickening of the surface, while no major intraoperative and perioperative complications, such as necrosis or severe bleeding were observed. Minor complications like oedema or exfoliation were mild. All 17 patients had a complete healing of the mucosal surface one week after treatment. The grade of effectiveness and the stability of the results correlated with the complexity of the VMs. This research may serve as groundwork for future studies that may aim to explore the use of this device on other vascular malformations. Level of evidence: Case series: level 4
Emerging challenges and possible strategies in maxillo-facial and oral surgery during the COVID-19 pandemic
Full text linkThe Coronavirus disease 2019 (COVID-19) pandemic suddenly took the world by storm and Italy was one of the hardest hit countries. Maxillo-facial surgery and dentistry procedures had to be significantly reorganized, since they are considered high-risk procedures. Protocols had to be changed and interdepartmental cooperation was put in place to plan surgical interventions and maintain high standards. Various improvements have been made to prevent and reduce the risks of spreading the infection. Even if the situation seems to have improved, being unprepared is not an option. In this paper the experience gained during these months has been shared and possible future challenges has been highlighted, suggesting practical adjustments based also on new guidelines and recommendations
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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