Italian position paper (SIPMO-SICMF) on medication-related osteonecrosis of the jaw (MRONJ).

OBJECTIVE: This paper aims to describe the 2023 update position paper on MRONJ developed by the Italian Societies of Oral Pathology and Medicine (SIPMO) and of Maxillofacial Surgery (SICMF). METHODS: This is the second update following the 2013 and 2020 Italian position papers by the Expert panel, which is a representation of the two scientific societies (SIPMO and SICMF). The paper is based on an extensive analysis of the available literature from January 2003 to February 2020, and the subsequent review of literature conducted between March 2020 and December 2022 to include all new relevant published papers to confirm or modify the previous set of recommendations. RESULTS: This position paper highlights the main issues of MRONJ on risk estimates, disease definition, diagnostic pathway, individual risk assessment, and the fundamental role of imaging in the diagnosis, classification, and management of MRONJ. CONCLUSION: The Expert Panel confirmed the MRONJ definition, the diagnostic work-up, the clinical-radiological staging system and the prophylactic drug holiday, as recognized by SIPMO-SICMF; while, it presented novel indications regarding the categories at risk of MRONJ, the prevention strategies, and the treatment strategies associated with the therapeutic drug holiday.

Thirteen-gene DNA methylation analysis of oral brushing samples: A potential surveillance tool for periodic monitoring of treated patients with oral cancer.

BACKGROUND: We evaluated the prognostic role of 13-gene DNA methylation analysis by oral brushing repeatedly performed during the follow-up of patients surgically treated for oral cancer. METHODS: This is a nested case-control study including 61 patients for a total of 64 outcomes (2/61 patients experienced multiple relapses). Samples were collected at baseline (4-10 months after OSCC resection) and repeatedly every 4-10 months until relapse or death. DNA methylation scores were classified as persistently positive, persistently negative, or mixed. RESULTS: Twenty cases who had persistently positive scores and 30 cases with mixed scores had, respectively, an almost 42-fold (p < 0.001) and 32-fold (p = 0.006) higher likelihood of relapse, compared to 14 patients with persistently negative scores. The last score before reoccurrence was positive in 18/19 secondary events. CONCLUSIONS: The 13-gene DNA methylation analysis may be considered for the surveillance of patients treated for oral carcinoma.

Pre-operative incisional biopsy of oral squamous cell carcinoma: high podoplanin expression is related to perineural invasion and may be a useful predictor of disease progression.

OBJECTIVE: Immunohistochemical analysis of podoplanin expression as a pre-operative molecular marker for perineural invasion (PNI) may represent an attractive strategy for surgical management of oral squamous cell cancer (OSCC). We evaluated the relationship between podoplanin expression and PNI in pre-operative incisional biopsies of OSCC. STUDY DESIGN: After performing pathological staging and histologic and immunohistochemical evaluation of 83 surgical specimens, we performed multivariable logistic regression analysis to examine the relationship between PNI and independent variables. To evaluate the utility of podoplanin immunopositivity for discrimination of PNI status pre-operatively, we calculated the sensitivity, specificity, positive predictive value, and negative predictive value. We performed receiver operating characteristic curve analysis to evaluate the diagnostic accuracy of podoplanin immunopositivity for predicting PNI alone and in combination with age, T stage, N stage, and index site. RESULTS: We observed podoplanin expression in 42 (50.6%) of all the 83 pre-operative incisional biopsies and 29 of the pre-operative biopsies of the 31 (93.5%) postoperative specimens with PNI. The rate of podoplanin expression was significantly higher in patients with pT3 to pT4 stage and pN+ stage disease. Podoplanin positivity in the pre-operative biopsy showed high sensitivity in predicting PNI in the surgical specimen. CONCLUSION: Podoplanin expression appears to be an independent pre-operative variable significantly related to PNI and a possibly valuable prognostic marker for therapeutical planning and surgical treatment of OSCC.

Soft tissue prediction in orthognathic surgery: Improving accuracy by means of anatomical details.

Three-dimensional virtual simulation of orthognathic surgery is now a well-established method in maxillo-facial surgery. The commercial software packages are still burdened by a consistent imprecision on soft tissue predictions. In this study, the authors produced an anatomically detailed patient specific numerical model for simulation of soft tissue changes in orthognathic surgery. Eight patients were prospectively enrolled. Each patient underwent CBCT and planar x-rays prior to surgery and in addition received an MRI scan. Postoperative soft-tissue change was simulated using Finite Element Modeling (FEM) relying on a patient-specific 3D models generated combining data from preoperative CBCT (hard tissue) scans and MRI scans (muscles and skin). An initial simulation was performed assuming that all the muscles and the other soft tissue had the same material properties (Homogeneous Model). This model was compared with the postoperative CBCT 3D simulation for validation purpose. Design of experiments (DoE) was used to assess the effect of the presence of the muscles considered and of their variation in stiffness. The effect of single muscles was evaluated in specific areas of the midface. The quantitative distance error between the homogeneous model and actual patient surfaces for the midface area was 0.55 mm, standard deviation 2.9 mm. In our experience, including muscles in the numerical simulation of orthognathic surgery, brought an improvement in the quality of the simulation obtained.

Is Beauty a Matter of Volume Distribution? Proposal of a New Aesthetic Three-Dimensional Guide in Orthognathic Surgery.

BACKGROUND: Orthognathic surgery is a multidisciplinary surgery in which the aesthetic results have become increasingly important, and consequently, also the predictability of the surgical outcomes. In this paper, we analyzed the volumetric distribution of the lower two-thirds of the face, in patients operated by orthognathic surgery and selected for their attractiveness. Our goal was to analyze the aesthetic volumetric distribution for gender and to propose our operating philosophy, that a normative distribution of facial volumes could be used like a new 3D aesthetic guide in orthognathic planning. METHODS: A group of 46 orthognathic patients (26 females, 20 males) with the best postoperative aesthetic score was selected by a jury of plastic surgeons, orthodontists, and journalists. The mean soft tissue volumes of the malar, maxillary, mandibular, and chin regions were analyzed. RESULTS: Overall, we measured a mean female facial volume distribution of 38.7%, 29%, 27.6%, and 4.7%, respectively, in the malar, maxillary, mandibular, and chin regions, while in males, it was 37%, 26%, 30%, and 6%, respectively. CONCLUSIONS: In this paper, the expansion of facial volumes in orthognathic surgery is proposed as a key point for facial harmonization. Beauty could be scientifically interpreted as a balanced distribution of facial volumes, and the virtual study of this distribution can become an important part of the preoperative analysis, such as a "volumetric" 3D cephalometry, where the surgeon could use average values of aesthetic volumetric distribution as preoperative surgical references.

Sural Nerve Vertical Cross-Face Graft for Lacrimal Gland Neurotization to Improve Tear Secretion in Neurodeprivative Dry Eye.

PURPOSE: No specific interventions have been reported for the treatment of severe neurodeprivative dry eye disease owing to facial nerve palsy. We describe herein the feasibility of a novel surgical procedure to reinnervate the lacrimal gland and report the preliminary outcomes of the first series of patients who were treated accordingly. METHODS: Prospective interventional case series including consecutive patients affected by facial palsy with absolute deficiency of tear secretion who underwent lacrimal gland neurotization. A sural nerve vertical cross-face graft was used to connect the lacrimal gland with the parasympathetic branch of the lingual nerve directed to the contralateral submandibular gland. RESULTS: Lacrimal neurotization was performed uneventfully in 10 patients (4 M, 6 F; mean age 47.1 ± 17.1 years). In all cases, the procedure was combined with facial reanimation, while corneal neurotization was performed in 4 cases. One year postoperatively, mean values of a Schirmer test increased significantly compared with baseline values (7.56 ± 7.84 vs. 0 ± 0 mm/5 min; P = 0.02), while the mean daily number of instillation of tear substitutes decreased significantly (21.8 ± 4.5 vs. 7.1 ± 2.2; P = 0.009). Overall, all patients were satisfied with surgery (very satisfied: n = 7 and satisfied: n = 2). No major postoperative complications occurred. CONCLUSIONS: Vertical cross-face using a sural nerve graft to connect the lacrimal gland with the contralateral submandibular gland is a novel technique for treating patients with facial nerve palsy and severe neurodeprivative dry eye disease. This surgery both performed alone and combined with corneal neurotization is able to improve tear secretion and decrease the need for frequent instillations of tear substitutes.

Shared epigenetic alterations between oral cancer and periodontitis: A preliminary study.

INTRODUCTION: We recently developed a non-invasive sampling procedure for oral squamous cell carcinoma (OSCC) detection based on DNA methylation analysis of a panel of 13 genes. Oral cancer, as well as acute and chronic inflammatory diseases, may influence the methylation level of several genes in the oral cavity. In the present study, we evaluated the presence of periodontal disease (PD) and the methylation status using our 13-gene panel. METHODS: Oral brushing specimens were collected from three different patient groups: 23 gingival OSCC patients, 15 patients affected by PD, and 15 healthy volunteers lacking evidence of PD. DNA methylation analysis was performed and each sample was determined to be positive or negative based on a predefined cut-off value. RESULTS: Positive results were found for 23/23 OSCC patients, 3/15 PD patients, and 0/15 samples from healthy volunteers. The GP1BB and MIR193 genes in the PD group exhibited mean methylation levels similar to OSCC patients. ZAP70 showed different methylation levels among three groups. CONCLUSION: Preliminary data identified shared epigenetic alterations between PD and OSCC patients in two inflammatory genes (GP1BB and MIR193). This study may help to identify potential links between the two diseases and serve as a starting point for the future research focused on pathogenesis.

Three-dimensional cephalometric outcome predictability of virtual orthodontic-surgical planning in surgery-first approach.

OBJECTIVES: The aim of this study is to introduce a novel 3D cephalometric analysis (3DCA) and to validate its use in evaluating the reproducibility of virtual orthodontic-surgical planning (VOSP) in surgery-first approach (SF) comparing VOSP and post-operative outcome (PostOp). METHODS: The cohort of nineteen patients underwent bimaxillary orthognathic surgery following the VOSP designed in SimPlant O&O software by processing cone-beam computed tomography (CBCT) scans and intraoral digital scanning of the dental arches. Said records were re-acquired once the post-operative orthodontic treatment was completed. The 3DCA was performed by three expert operators on VOSP and PostOp 3D models. Descriptive statistics of 3DCA measures were evaluated, and outcomes were compared via Wilcoxon test. RESULTS: In the comparison between cephalometric outcomes against planned ones, the following values showed significant differences: Wits Index, which suggests a tendency towards skeletal class III in PostOp (p = 0.033); decreased PFH/AFH ratio (p = 0.010); decreased upper incisors inclination (p < 0.001); and increased OVJ (p = 0.001). However not significant (p = 0.053), a tendency towards maxillary retroposition was found in PostOp (A/McNamara VOSP: 5.05 ± 2.64 mm; PostOp: 4.1 ± 2.6 mm). On average, however, when McNamara's plane was considered as reference, a tendency to biprotrusion was found. Upper incisal protrusion was greater in PostOp as an orthodontic compensation for residual maxillary retrusion (VOSP: 5.68 ± 2.56 mm; PostOp: 6.53 ± 2.63 mm; p = 0.084). Finally, the frontal symmetry in relation to the median sagittal plane decreased in craniocaudal direction. LIMITATIONS: A potential limit of studies making use of closest point distance analysis is represented by the complexity that surgeons and orthodontists face in applying this three-dimensional evaluation of SF accuracy/predictability to everyday clinical practice and diagnosis. Also, heterogeneity and limited sample size may impact the results of the study comparison. CONCLUSIONS: The presented 3DCA offers a valid aid in performing VOSP and analysing orthognathic surgery outcomes, especially in SF. Thanks to the cephalometric analysis, we found that surgery-first approach outcome unpredictability is mainly tied to the sagittal positioning of the maxilla and that the transverse symmetry is progressively less predictable in a craniocaudal direction.

A 3-Dimensional Evaluation of Bone Density in Alveolar Cleft Grafting Methods: Bone Substitutes Versus Autologous Bone.

INTRODUCTION: Secondary alveolar cleft repair using autologous bone graft is currently the gold standard in treating residual alveolar clefts. Despite its effectiveness, this technique is still burdened by several withdrawals, mostly related to donor site morbidity. To decrease disadvantages for patients, numerous attempts in the literature regarding bone substitutes have been described. The aim of this study is to compare the viability of bovine-based replacement bone material with respect of autologous bone graft in alveolar cleft reconstruction, through 3-dimensional alveolar cleft segmentation and bone density evaluation from preoperative and postoperative cone-beam computed tomography. PATIENTS AND METHODS: A retrospective cohort study of 10 patients who underwent surgical procedure for alveolar cleft grafting at Sant'Orsola Malpighi University Hospital of Bologna from December 2012 to December 2016 was undertaken. Five patients received autologous bone graft and 5 a bovine bone substitute graft. Preoperative and immediate postoperative orthopanoramic x-rays were recorded. Cone-beam computed tomography scans have recorded both pre and postoperatively. Volumetric evaluation on 3-dimensional cone-beam computed tomography images was performed. RESULTS: Alveolar clefts repaired using substitute bovine bone/biological membrane scaffold had a mean fill of 69.00% of total cleft volume, while this figure was of 67.07% with autologous bone grafting. The immediate postoperative course and subsequent discharge were uneventful for both groups, with a difference in timing. The cost of substitute bovine bone was offset by cost savings associated with a reduction in operative and postoperative and hospitalization time. CONCLUSIONS: Bone substitutes showed to be a promising solution in alveolar cleft grafting.

Guided bone regeneration using titanium mesh to augment 3-dimensional alveolar defects prior to implant placement. A pilot study.

OBJECTIVES: To evaluate the outcomes of bone regeneration using a customized titanium mesh scaffold to cover a bone graft for reconstruction of complex defects of the jaws. MATERIALS AND METHODS: 19 large defects were digitally reconstructed using CT scans according to the prosthetic requirements. A titanium mesh scaffold was designed to cover the bone (autologous/bovine bone particulate) graft. At least 6 months after surgery, a new cone-beam CT was taken. The pre- and postoperative CT datasets were then converted into three-dimensional models and digitally aligned. The actual mesh position was compared to the virtual position to assess the reliability of the digital project. The reconstructed bone volumes (RBVs) were calculated according to the planned bone volumes (PBVs), outlining the areas under the mesh. These values were then correlated with the number of exposures, locations of atrophy, and virtually planned bone volume. RESULTS: The mean matching value between the planned position of the mesh and the actual one was 82 ± 13.4%. 52.3% (40% early and 60% late) exposures were observed, with 15.8% exhibiting infection. 26.3% resulted as failures. The amount of reconstructed bone volume (RBV) in respect to PBV was 65 ± 40.5%, including failures, and 88.2 ± 8.32% without considering the failures. The results of the exposure event were statistically significant (p = .006) in conditioning the bone volume regenerated. CONCLUSIONS: This study obtained up to 88% of bone regeneration in 74% of the cases. The failures encountered (26%) should underline the operator's expertise relevance in conditioning the final result.

AEducaAR, Anatomical Education in Augmented Reality: A Pilot Experience of an Innovative Educational Tool Combining AR Technology and 3D Printing.

Gross anatomy knowledge is an essential element for medical students in their education, and nowadays, cadaver-based instruction represents the main instructional tool able to provide three-dimensional (3D) and topographical comprehensions. The aim of the study was to develop and test a prototype of an innovative tool for medical education in human anatomy based on the combination of augmented reality (AR) technology and a tangible 3D printed model that can be explored and manipulated by trainees, thus favoring a three-dimensional and topographical learning approach. After development of the tool, called AEducaAR (Anatomical Education with Augmented Reality), it was tested and evaluated by 62 second-year degree medical students attending the human anatomy course at the International School of Medicine and Surgery of the University of Bologna. Students were divided into two groups: AEducaAR-based learning ("AEducaAR group") was compared to standard learning using human anatomy atlas ("Control group"). Both groups performed an objective test and an anonymous questionnaire. In the objective test, the results showed no significant difference between the two learning methods; instead, in the questionnaire, students showed enthusiasm and interest for the new tool and highlighted its training potentiality in open-ended comments. Therefore, the presented AEducaAR tool, once implemented, may contribute to enhancing students' motivation for learning, increasing long-term memory retention and 3D comprehension of anatomical structures. Moreover, this new tool might help medical students to approach to innovative medical devices and technologies useful in their future careers.

Validation of a Cleanroom Compliant Sonication-Based Decellularization Technique: A New Concept in Nerve Allograft Production.

Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze-thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique.

Corneal Neurotization: A Novel Surgical Procedure for Neurotrophic Keratopathy.

PURPOSE: The aim of this study is to describe techniques, results, and open issues of corneal neurotization (CN) for the treatment of neurotrophic keratopathy (NK). METHODS: An overview of the most important studies of CN is provided. The 2 main surgical approaches (namely, direct CN and indirect CN) with specific advantages and disadvantages are described. The results regarding changes of corneal sensitivity and clarity, visual acuity, and in vivo confocal microscopy metrics are summarized. Ex vivo studies with histopathology of the neurotized cornea are reported. Intraoperative and early and late postoperative complications are described along with current open issues to be further clarified. RESULTS: Corneal sensitivity improves after both direct and indirect CN. Corneal reinnervation allows the healing of NK in almost the totality of the operated eyes, determining a corresponding improvement of corneal clarity and visual acuity. Regeneration of corneal nerve fibers is confirmed by means of either in vivo confocal microscopy or ex vivo histopathology. Few self-limiting complications are reported during the postoperative course. Current open issues concern the identification of the technique of choice, the use of autograft or allograft, and the timing of CN either when performed alone or when combined with other surgeries. CONCLUSIONS: CN represents a game-changing surgical procedure for NK, which has the potential to restore corneal sensitivity in all stages of the disease regardless of the mechanism of denervation. Further long-term results are needed to confirm its efficacy over time. The design of randomized clinical trials comparing CN with noninterventional therapies could further validate the adoption of this technique.

PSI-Guided Mandible-First Orthognathic Surgery: Maxillo-Mandibular Position Accuracy and Vertical Dimension Adjustability.

In orthognathic surgery, patient-specific osteosynthesis implants (PSIs) represent a novel approach for the reproduction of the virtual surgical planning on the patient. The aim of this study is to analyse the quality of maxillo-mandibular positioning using a hybrid mandible-first mandibular-PSI-guided procedure on twenty-two patients while the upper maxilla was fixed using manually bent stock titanium miniplates. The virtual surgical plan was used to design PSIs and positioning guides, which were then 3D printed using biocompatible materials. A Cone Beam Computed Tomography (CBCT) scan was performed one month after surgery and postoperative facial skeletal models were segmented for comparison against the surgical plan. A three-dimensional cephalometric analysis was carried out on both planned and obtained anatomies. A Spearman correlation matrix was computed on the calculated discrepancies in order to achieve a more comprehensive description of maxillo-mandibular displacement. Intraoperatively, all PSIs were successfully applied. The procedure was found to be accurate in planned maxillo-mandibular positioning reproduction, while maintaining a degree of flexibility to allow for aesthetics-based verticality correction in a pitch range between -5.31 and +1.79 mm. Such a correction did not significantly affect the achievement of planned frontal symmetry.

Dynamic Navigation in Implant Dentistry: A Systematic Review and Meta-analysis.

PURPOSE: Dynamic navigation is a technique that allows for the placement of dental implants using a computer-guided approach according to preoperative planning. Its accuracy has been assessed in several previous studies. The purpose of this study was to summarize data on implant placement accuracy using dynamic navigation, to synthesize the frequency of intraoperative complications and implant failures, and to compare this technique with static computer-guided surgery and a freehand approach. MATERIALS AND METHODS: Electronic and manual literature searches until December 2019 were performed. The outcome variables were implant placement accuracy using dynamic navigation, accuracy differences between dynamic and static techniques and between dynamic and freehand techniques, intraoperative complications, and implant failures. Random-effects meta-analyses were performed. RESULTS: A total of 32 studies were included; 29 reported accuracy values (2,756 implants), and 10 focused on complications and implant failures (1,039 implants). The pooled mean implant placement errors were 0.81 (95% CI: 0.677 to 0.943) mm at the entry point and 0.910 (95% CI: 0.770 to 1.049) mm at the apical point. The pooled mean vertical and angular deviations were 0.899 (95% CI: 0.721 to 1.078) mm and 3.807 (95% CI: 3.083 to 4.530) degrees. The navigation group showed significantly lower implant placement errors with respect to the freehand technique (P < .01) and similar accuracy values (P ≥ .05) compared with the static technique. The pooled prevalence of failures was 1% (95% CI: 0.00% to 2%). CONCLUSION: Dynamic navigation provided small implant placement errors, comparable with those obtained using static computer-guided surgery, and can be considered a more accurate technique than conventional freehand surgery.

Flapless and bone-preserving extraction of partially impacted mandibular third molars with dynamic navigation technology. A report of three cases.

AIM: Most of the intra- and postoperative patient discomfort related to complex mandibular third molar (M3M) extraction is proportional to the invasiveness of the surgery. This can be minimized through the support of dynamic navigation (DN) technology, which can be successfully applied in dental implantology. Materials and methods: Three patients, one female (aged 25 years) and two males (aged 18 and 51 years, respectively) underwent the DN-supported extraction of partially impacted M3Ms with a flapless approach that required minimal bone removal. The patients' discomfort and the speed of recovery were considered to be proof of the quality of the adopted procedure. RESULTS: No postoperative discomfort such as pain or swelling was recorded in the immediate postoperative period, and no complications were reported within a month of the surgery. No medications were prescribed. The procedure lasted no longer than 20 min in all cases. CONCLUSION: Using DN technology, the real-time 3D monitoring of the clinical situation in each surgical phase enabled the surgeon to avoid soft tissue detachment as well as limit bone loss and intraoperative bleeding, thanks to a precise multi--section of the tooth and important nearby anatomical structures, respectively.

Mandibular reconstruction using a new design for a patient-specific plate to support a fibular free flap and avoid double-barrel technique.

Mandibular reconstruction is a primary concern for head and neck reconstructive surgeons because of the aesthetic restoration needs after ablative surgery, as well as for functional reasons: the mandible has a central functional role in speaking, swallowing and mastication. It is generally agreed that the gold standard for mandibular reconstruction is a bone free flap supported by a reconstructive titanium plate. The fibular flap represents the first choice for multi-segment mandibular reconstruction. The fibula, harvested as a single barrel graft, does not exhibit sufficient thickness to reach the original height of the native mandible; therefore, the positioning of dental implants is often deeper than that of the native alveolar crest. The aim of this study was to evaluate the positioning of the fibular free flap as it pertains to the restoration of vertical mandible height, by modifying the design of a 3D-printed titanium patient-specific implant (PSI). In this novel reconstructive workflow, the customised plate was projected to support the fibular flap at an alveolar bone position above the typical inferior mandibular border, and carried out on four patients. All patients were treated for benign neoplasms involving mandibular bone. Clinical outcomes and accuracy of the procedure are described. Our reconstructive proposal appears to be a valid alternative to the double-barrel technique in order to restore the vertical height of the reconstructed mandible.^ieng

La ricostruzione mandibolare è particolarmente rilevante per il chirurgo cervico-cefalico, in quanto influenza significativamente i successi in termini di risultati estetici e funzionali per il paziente. Il gold standard per tale ricostruzione è l'utilizzo di lembi ossei rivascolarizzati, stabilizzati mediante una placca ricostruttiva in titanio. Il lembo di fibula rappresenta la prima scelta ricostruttiva laddove necessitino molteplici segmenti ossei. Tuttavia questo lembo, allestito secondo la tecnica della singola barra, non permette di ripristinare l'altezza mandibolare nativa, adeguata per una corretta riabilitazione masticatoria implanto-supportata. Lo scopo di questo studio è quindi presentare un nuovo design di placca ricostruttiva custom-made, atta a posizionare il segmento osseo di fibula in una posizione più coronale, evitando pertanto la necessità di allestire il lembo secondo la tecnica della doppia barra. La placca custom-made contribuisce inoltre al mantenimento del profilo mandibolare, garantendo il ripristino morfologico della ricostruzione. Questo protocollo è stato eseguito su quattro pazienti sottoposti a resezione mandibolare per tumori benigni. I risultati clinici e di accuratezza della procedura sono presentati. Il protocollo presentato sembra una valida alternativa alla tecnica della doppia barra al fine di ripristinare l'altezza mandibolare nativa.

Existence of a Neutral-Impact Maxillo-Mandibular Displacement on Upper Airways Morphology.

Current scientific evidence on how orthognathic surgery affects the airways morphology remains contradictory. The aim of this study is to investigate the existence and extension of a neutral-impact interval of bony segments displacement on the upper airways morphology. Its upper boundary would behave as a skeletal displacement threshold differentiating minor and major jaw repositioning, with impact on the planning of the individual case. Pre- and post-operative cone beam computed tomographies (CBCTs) of 45 patients who underwent maxillo-mandibular advancement or maxillary advancement/mandibular setback were analysed by means of a semi-automated three-dimensional (3D) method; 3D models of skull and airways were produced, the latter divided into the three pharyngeal subregions. The correlation between skeletal displacement, stacked surface area and volume was investigated. The displacement threshold was identified by setting three ∆Area percentage variations. No significant difference in area and volume emerged from the comparison of the two surgical procedures with bone repositioning below the threshold (approximated to +5 mm). A threshold ranging from +4.8 to +7 mm was identified, varying in relation to the three ∆Area percentages considered. The ∆Area increased linearly above the threshold, while showing no consistency in the interval ranging from -5 mm to +5 mm.

Clinical validation of 13-gene DNA methylation analysis in oral brushing samples for detection of oral carcinoma: Italian multicenter study.

BACKGROUND: The aim of this Italian multicenter study was to evaluate the diagnostic performance of a minimally invasive method for the detection of oral squamous cell carcinoma (OSCC) based on 13-gene DNA methylation analysis in oral brushing samples. METHODS: Oral brushing specimens were collected in 11 oral medicine centers across Italy. Twenty brushing specimens were collected by each center, 10 from patients with OSCC, and 10 from healthy volunteers. DNA methylation analysis was performed in blindness, and each sample was determined as positive or negative based on a predefined cutoff value. RESULTS: DNA amplification failed in 4 of 220 (1.8%) samples. Of the specimens derived from patients with OSCC, 93.6% (103/110) were detected as positive, and 84.9% (90/106) of the samples from healthy volunteers were negative. CONCLUSION: These data confirmed the diagnostic performance of our novel procedure in a large cohort of brushing specimens collected from 11 different centers and analyzed in blindness.

Augmented Reality to Assist Skin Paddle Harvesting in Osteomyocutaneous Fibular Flap Reconstructive Surgery: A Pilot Evaluation on a 3D-Printed Leg Phantom.

BACKGROUND: Augmented Reality (AR) represents an evolution of navigation-assisted surgery, providing surgeons with a virtual aid contextually merged with the real surgical field. We recently reported a case series of AR-assisted fibular flap harvesting for mandibular reconstruction. However, the registration accuracy between the real and the virtual content needs to be systematically evaluated before widely promoting this tool in clinical practice. In this paper, after description of the AR based protocol implemented for both tablet and HoloLens 2 smart glasses, we evaluated in a first test session the achievable registration accuracy with the two display solutions, and in a second test session the success rate in executing the AR-guided skin paddle incision task on a 3D printed leg phantom. METHODS: From a real computed tomography dataset, 3D virtual models of a human leg, including fibula, arteries and skin with planned paddle profile for harvesting, were obtained. All virtual models were imported into Unity software to develop a marker-less AR application suitable to be used both via tablet and via HoloLens 2 headset. The registration accuracy for both solutions was verified on a 3D printed leg phantom obtained from the virtual models, by repeatedly applying the tracking function and computing pose deviations between the AR-projected virtual skin paddle profile and the real one transferred to the phantom via a CAD/CAM cutting guide. The success rate in completing the AR-guided task of skin paddle harvesting was evaluated using CAD/CAM templates positioned on the phantom model surface. RESULTS: On average, the marker-less AR protocol showed comparable registration errors (ranging within 1-5 mm) for tablet-based and HoloLens-based solution. Registration accuracy seems to be quite sensitive to ambient light conditions. We found a good success rate in completing the AR-guided task within an error margin of 4 mm (97% and 100% for tablet and HoloLens, respectively). All subjects reported greater usability and ergonomics for HoloLens 2 solution. CONCLUSIONS: Results revealed that the proposed marker-less AR based protocol may guarantee a registration error within 1-5 mm for assisting skin paddle harvesting in the clinical setting. Optimal lightening conditions and further improvement of marker-less tracking technologies have the potential to increase the efficiency and precision of this AR-assisted reconstructive surgery.