Mutational landscape of HSP family on human breast cancer.

Breast cancer (BRCA) is a prevalent malignancy with the highest incidence among females. BRCA can be categorized into five intrinsic molecular subtypes (LumA, LumB, HER2, Basal, and Normal), each characterized by varying molecular and clinical features determined by the expression of intrinsic genes (PAM50). The Heat Shock Protein (HSP) family is composed of 95 genes evolutionary conservated, they have critical roles in proteostasis in both normal and cancerous processes. Many studies have linked HSP to the development and spread of cancer. They modulate the activity of multiple proteins expressed by oncogenes and anti-oncogenes through a range of interactions. In this study, we evaluate the mutational changes that HSP undergoes in BRCA mainly from the TCGA database. We observe that Copy Number Variations (CNV) are the more frequent events analyzed surpassing the occurrence of point mutations, indels, and translation start site mutations. The Basal subtype showcased the highest count of amplified CNV, including subtype-specific changes, whereas the Luminals tumors accumulated the greatest number of deletion CNV. Meanwhile, the HER2 subtype exhibited a comparatively lower frequency of CNV alterations when compared to the other subtypes. This study integrates CNV and expression data, finding associations between these two variables and the influence of CNV on the deregulation of HSP expression. To enhance the role of HSP as a risk predictor in BRCA, we succeeded in identifying CNV profiles as a prognostic marker. We included Artificial Intelligence to improve the clustering of patients, and we achieved a molecular CNV signature as a significant risk factor independent of known classic markers, including molecular subtypes PAM50. This research enhances the comprehension of HSP DNA alterations in BRCA and its relation with predicting the risk of affected individuals providing insights to develop guide personalized treatment strategies.

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.

Retention strength of ball-attachment titanium post for removable partial denture or overdenture

Aim: To evaluate the retention of an endodontic titanium postwith a spherical head for removable partial denture or overdentureattachment according to surface treatment type. Methods: Sixtyhealthy single-rooted teeth, sectioned at the enamel/cementumjunction, were treated endodontically and steadily fixed in theembedding acrylic resin. The titanium posts were subdivided intofour groups: control, no surface treatment (Ctrl); posts with macroretentivegrooves (MR); air abrasion of the post surface (AB); andposts with macro-retentive grooves and air abrasion of the postsurface (MR+AB). The posts were luted in the root canal usingself-adhesive dual resin cement. Pull-out testing was performedusing a universal testing machine until complete detachment wasachieved. After pull-out testing, the metallic posts were examinedunder an optical microscope and the failures were classifiedbased on the cement distribution pattern on the extracted posts:0, no cement left on the post (cement/post failure); 1, postsurface partially covered by adhered cement (post/cement anddentin/cement mixed failure); 2, post surface completely coveredby cement (dentin/cement failure). The retention data wereanalyzed by one-way ANOVA, Bonferroni­Dunn test (p<0.05)and Weibull analysis. Results: AB showed the highest retentionvalue (485.37±68.36), followed by MR+AB (355.80±118.47), MR(224.63±42.54) and Ctrl (113.12 ± 51.32). AB and MR showedthe highest Weibull moduli. Conclusions: The data indicatedthat air abrasion alone could significantly increase the retentionof titanium posts/attachments for use with overdentures orremovable partial denture

Fatigue resistance of monolithic lithium disilicate occlusal veneers: a pilot study.

The use of thin lithium disilicate (LD) occlusal veneers is an effective method to increase the vertical dimension of occlusion in cases of tooth wear. However, doubt remains regarding the threshold thickness to be used in this restoration class. This study aims to evaluate the effect of ceramic thickness on the survival rate and failure pattern of LD molar veneer restorations using a simplified fatigue testing machine. Sixty sound, freshly extracted human molars were used. Three groups (n = 20) were randomly created with different ceramic thicknesses (0.5, 0.8, and 1.2 mm), and 60 LD IPS e.max Press LT occlusal veneers were fabricated. The ceramic restorations were luted with a resin cement. The stainless-steel rotating drum of the ball mill contained 10 zirconia (Y-TZP) and 10 stainless steel spheres, in 500 mL of distilled water at 37 ± 1 °C. Crack growth in the LD restorations was evaluated under a stereomicroscope following each fatigue testing run (12 60-min runs). Progressive damage was observed as a function of cycling time. Survival was significantly influenced by the restoration thickness (p = 0.002, log-rank test), with thicker restorations exhibiting a higher survival rate. Thinner restorations (0.5 mm) showed significantly lower survival rate than 0.8- and 1.2-mm restorations (p < 0.016); no significant difference was observed between the 0.8- and 1.2-mm restorations. A threshold value of 0.8 mm may represent an acceptable compromise between fatigue resistance and tooth reduction.

In vitro assessment of the accuracy of digital impressions prepared using a single system for full-arch restorations on implants.

PURPOSE: This study describes a method for measuring the accuracy of the virtual impression. METHODS: In vitro measurements according to a metrological approach were based on (1) use of an opto-mechanical coordinate measuring machine to acquire 3D points from a master model, (2) the mathematical reconstruction of regular geometric features (planes, cylinders, points) from 3D points or an STL file, and (3) consistent definition and evaluation of position and distance errors describing scanning inaccuracies. Two expert and two inexpert operators each made five impressions. The 3D position error, with its relevant X, Y, and Z components, the mean 3D position error of each scanbody, and the intra-scanbody distance error were measured using the analysis of variance and the Sheffe's test for multiple comparison. RESULTS: Statistically significant differences in the accuracy of the impression were observed among the operators for each scanbody, despite the good reliability (Cronbach's [Formula: see text] = 0.897). The mean 3D position error of the digital impression was between 0.041 ± 0.023 mm and 0.082 ± 0.030 mm. CONCLUSIONS: Within the limitations of this in vitro study, which was performed using a single commercial system for preparing digital impressions and one test configuration, the data showed that the digital impressions had a level of accuracy comparable to that reported in other studies, and which was acceptable for clinical and technological applications. The distance between the individual positions (#36 to #46) of the scanbody influenced the magnitude of the error. The position error generated by the intraoral scanner was dependent on the length of the arch scanned. Operator skill and experience may influence the accuracy of the impression.

Prosthetically CAD-CAM-Guided Bone Augmentation of Atrophic Jaws Using Customized Titanium Mesh: Preliminary Results of an Open Prospective Study.

This study evaluated the outcomes of computer-aided design-computer-aided machining (CAD-CAM)-customized titanium mesh used for prosthetically guided bone augmentation related to the occlusion-driven implant position, to the vertical bone volume gain of the mandible and maxilla, and to complications, such as mesh exposure. Nine patients scheduled for bone augmentation of atrophic sites were treated with custom titanium mesh and particulate bone grafts with autologous bone and anorganic bovine bone in a 1:1 ratio prior to implant surgery. The bone volume needed to augment was virtually projected based on implant position, width, and length, and the mesh design was programmed for the necessary retaining screws. After 6 to 8 months, bone augmentations of 1.72 to 4.1 mm (mean: 3.83 mm) for the mandibular arch and 2.14 to 6.88 mm (mean: 3.95 mm) for the maxilla were registered on cone-beam computerized tomography. Mesh premature (within 4 to 6 weeks) exposure was observed in 3 cases and delayed (after 4 to 6 weeks) in 3 other cases. One titanium mesh was removed before the programmed time but in all augmented sites was possible implant insertion. No complication occurred during prosthetic follow-up. Using CAD-CAM technology for prosthetically guided bone augmentation showed important postoperative morbidity of mesh exposure (66%). Because of this high prevalence of mesh exposure and the potential infection that could affect the expected bone augmentation, this study suggests a cautious approach to this procedure when designing the titanium mesh, to avoid flap tension that may cause mucosal rupture.

Short-term outcomes of mandibular reconstruction in oncological patients using a CAD/CAM prosthesis including a condyle supporting a fibular free flap.

PURPOSE: Condylar reconstruction and replacement using alloplastic materials currently attracts much surgical interest. The major challenge is to functionally reconstruct the anatomical region; this is crucial in terms of correct mandibular function. The goal of the present study was to evaluate the clinical outcomes of and complications experienced by a series of oncological patients who underwent computer-aided design/computer-aided manufacturing (CAD/CAM) condylar reconstruction following resection-disarticulation of the mandible. MATERIALS AND METHODS: We included nine patients who underwent disarticulation resection surgery to treat benign and malignant mandibular tumors involving the condylar region. All resections preserved the articular meniscus and featured placement of a CAD/CAM reconstructive plate supporting a fibular, microvascular free flap. The head of the prosthetic condyle reproduced the anatomical morphology of the native condyle. Patients were clinically evaluated in terms of occlusion stability, mandibular functional recovery, static and dynamic pain, and preservation of the normal mandibular contour. Planning and postoperative computed tomography (CT) scans were superimposed to assess the accuracy of reconstruction. RESULTS: No patient experienced plate exposure and, on direct clinical examination, no patient complained of joint pain. No patient developed plate loosening. No resorption of the glenoid fossa was evident when pre- and postoperative bone thicknesses were compared by CT. Preoperative occlusion was preserved in all dentate patients. One patient exhibited condylar displacement. In terms of reconstructive accuracy, the average postoperative deviation of the condyle from the preoperative position was 3.8 mm (range: 1.3-6.7 mm). CONCLUSIONS: The clinical outcomes of our series of oncological patients who underwent reconstruction using CAD/CAM plates including condyles were encouraging. The utility of our protocol needs to be confirmed in larger patient series.

Surgical reconstruction of maxillary defects using a computer-assisted design/computer-assisted manufacturing-produced titanium mesh supporting a free flap.

The maxilla provides support to the overlying structures and contributes significantly to the overall facial appearance and to critical functions such as mastication, speech, and deglutition. Many different techniques have been used over the years to achieve this reconstructive goal. Modern computer-assisted surgery affords new methods for planning resections, as well as optimising reconstructive outcomes and functional rehabilitation. The aim of this study was to describe our experience with, and technique for, the functional, structural, and aesthetic reconstruction of maxillary bone defects using a computer-assisted design (CAD)/computer-assisted manufacturing (CAM)-printed titanium mesh to provide structural support for free flap reconstruction. Four patients who underwent reconstruction with a CAD/CAM-printed titanium mesh were included in this study. The preoperative computed tomography (CT) data set used for virtual planning was superimposed onto the postoperative CT scan to calculate the difference between the virtually planned position and the postoperative position of the titanium mesh. The orbital floor and alveolus were the most frequent sites of deviation, and good reproducibility could be obtained with less than 1 mm of deviation between planning and results in most regions. Printed titanium meshes obtained with CAD/CAM technology and used to structurally support free flaps provide a valuable method for the achievement of good aesthetic, structural, and functional outcomes in maxillary reconstruction. Reconstructive accuracy using this technique is reasonably high. Further studies with a larger number of patients would be useful to confirm these results.

Is a computer-assisted design and computer-assisted manufacturing method for mandibular reconstruction economically viable?

The design and manufacture of patient-specific mandibular reconstruction plates, particularly in combination with cutting guides, has created many new opportunities for the planning and implementation of mandibular reconstruction. Although this surgical method is being used more widely and the outcomes appear to be improved, the question of the additional cost has to be discussed. To evaluate the cost generated by the management of this technology, we studied a cohort of patients treated for mandibular neoplasms. The population was divided into two groups of 20 patients each who were undergoing a 'traditional' freehand mandibular reconstruction or a computer-aided design/computer-aided manufacturing (CAD-CAM) mandibular reconstruction. Data concerning operation time, complications, and days of hospitalisation were used to evaluate costs related to the management of these patients. The mean operating time for the CAD-CAM group was 435 min, whereas that for the freehand group was 550.5 min. The total difference in terms of average time gain was 115.5 min. No microvascular complication occurred in the CAD-CAM group; two complications (10%) were observed in patients undergoing freehand reconstructions. The mean overall lengths of hospital stay were 13.8 days for the CAD-CAM group and 17 days for the freehand group. Finally, considering that the institutional cost per minute of theatre time is €30, the money saved as a result of the time gained was €3,450. This cost corresponds approximately to the total price of the CAD-CAM surgery. In conclusion, we believe that CAD-CAM technology for mandibular reconstruction will become a widely used reconstructive method and that its cost will be covered by gains in terms of surgical time, quality of reconstruction, and reduced complications.

A CAD-CAM-prototyped temporomandibular condyle connected to a bony plate to support a free fibula flap in patients undergoing mandiblectomy: A pilot study with 5 years of follow up.

Reconstruction of the condyle after an ablative procedure with the aim of cancer elimination remains surgically challenging. This pilot study focused on mandibular condylar replacement using CAD-CAM temporomandibular prostheses connected to customized reconstructive plates to support free fibula flaps in oncological patients. Five patients underwent mandibular disarticulation resection, and two of them completed their 5-year follow ups. The condylar anatomy, the position of the condyle within the glenoid fossa, and glenoid anatomy were measured by superimposing pre- and postoperative CT images (obtained after 6 months and 5 years of follow up). When comparing condyle anatomy, the shift was no more than 0.19 mm; when calculating condyle downward displacement the values were inferior to 2.92 mm; when analyzing glenoid fossa thickness, in case #1, glenoid fossa thickness increased by 0.62 and 0.48 mm at the 6-month and 5-year follow ups, respectively, and in case #2 were 0.50 and -0.11 mm, respectively. The hypothesis that the absence of anatomical change would prevent biodynamic alteration of tissues of the articulation chamber (the glenoid fossa, the synovial liquid, and the disc) was confirmed by the preliminary findings of this study.

Morphological results of customized microvascular mandibular reconstruction: A comparative study.

INTRODUCTION: Virtual planning and guided surgery with customized reconstructive plates are becoming more and more common for mandibular reconstruction with fibular free flaps. Although the literature describes many potential applications, no systematic analyses have been made about morphological results regarding computer-aided reconstruction compared to traditional freehand bent plate. MATERIALS AND METHODS: In the present study, we propose a comparative study in this innovative field, analysing a case series of 30 CAD/CAM reconstructed mandibles, compared to traditional reconstructed mandibles, in terms of morphological results. All patients were evaluated by pre-operative and a post-operative CT scan. To evaluate the morphological results, several anatomical landmarks were measured on CT scan: 1) the midline deviation; 2) the amplitude variation, in grades, of the mandibular angle; 3) the bi-gonial diameter of the mandibular and 4) the chin protrusion. RESULTS: The mean differences registered between pre-operative and post-operative CT scan were significantly better for test group regarding mandibular angle (p = 0.034), bi-gonial diameter (p = 0.041), chin protrusion (p = 0.05). No significant differences were registered for midline deviation (p = 0.092). CONCLUSION: CAD/CAM reconstructive technique appears to be a valid method to accurately restore the pre-operative morphological situation.

Mandibular reconstructions using computer-aided design/computer-aided manufacturing: A systematic review of a defect-based reconstructive algorithm.

Modern planning techniques, including computer-aided design/computer-aided manufacturing (CAD-CAM) can be used to plan reconstructive surgery, optimising aesthetic outcomes and functional rehabilitation. However, although many such applications are available, no systematic protocol yet describes the entire reconstructive procedure, which must include virtual planning, custom manufacture, and a reconstructive algorithm. We reviewed current practices in this novel field, analysed case series described in the literature, and developed a new, defect-based reconstructive algorithm. We also evaluated methods of mandibular reconstruction featuring virtual planning, the use of surgical guides, and laser printing of custom titanium bony plates to support composite free flaps, and evaluated their utility.

Evaluation of Masticatory Efficiency and QoL Improvements After Prosthetic Rehabilitation of Mandibular Cancer Patients Reconstructed with a Fibula Free Flap.

PURPOSE: The purpose of this noninferiority study was to determine whether removable or implant-supported fixed dental prostheses restored patients' abilities to preoperative levels after cancer removal in the mandible. MATERIALS AND METHODS: Ten patients who had undergone mandibular resection to remove cancer and subsequent reconstruction with microvascularized free fibula flaps were examined in this study. Five patients were rehabilitated with removable prostheses and five received implant-supported fixed prostheses. Health-related quality of life was evaluated using the Head and Neck (H&N30) questionnaire. Kruskal-Wallis nonparametric analysis of variance and Tamhane's T2 test were used to analyze results in comparison with a control group composed of 10 subjects with Class I natural dentition. RESULTS: Masticatory efficiency among the three groups of patients differed significantly (P=.003); in particular, that of the patients who received removable prostheses was not inferior to that of the control subjects (P=.019). Analysis of responses to the Head and Neck module of the Quality of Life Questionnaire showed no significant difference between patients with fixed dentures and patients with removable dentures. CONCLUSIONS: There is no apparent difference in quality of life between patients using implant-supported fixed prostheses and those using removable prostheses. Regarding masticatory efficiency, when feasible, the use of implant-supported fixed prostheses is recommended in patients who have undergone free fibula flap surgery, although the removable prostheses also were not inferior in patients who underwent no surgery.

Work flow for the prosthetic rehabilitation of atrophic patients with a minimal-intervention CAD/CAM approach.

The implant-supported fixed rehabilitation of patients with an atrophic edentulous crest remains a challenge if bone augmentation is not planned. A minimal intervention approach for bone regeneration is necessary to minimize the flap overextension needed to close the defect over the augmented bone. Prosthetically guided bone regeneration can determine the amount of bone augmentation necessary for definitive prosthetic fixed rehabilitation. The positions of the implants and prosthetic restoration were planned; a 0.3 mm thick titanium mesh was customized for bone augmentation by using computer-aided design and computer-aided manufacturing and rapid prototyped by laser sintering, and the definitive prosthetic rehabilitation was carried out according to the initial treatment plan. This resulted in minimal bone augmentation relative to the functional needs of the definitive prosthetic rehabilitation.

HER2 and ß-catenin protein location: importance in the prognosis of breast cancer patients and their correlation when breast cancer cells suffer stressful situations.

In human breast cancer, ß-catenin localization has been related with disease prognosis. Since HER2-positive patients are an important subgroup, and that in breast cancer cells a direct interaction of ß-catenin/HER2 has been reported, in the present study we have explored whether ß-catenin location is related with the disease survival. The study was performed in a tumor bank from patients (n = 140) that did not receive specific anti-HER2 therapy. The proteins were detected by immunohistochemistry in serial sections, 47 (33.5%) patients were HER2-positive with a long follow-up. HER2-positive patients that displayed ß-catenin at the plasma membrane (completely surrounding the tumour cells) showed a significant better disease-free survival and overall survival than the patients showing the protein on other locations. Then we explored the dynamics of the co-expression of ß-catenin and HER2 in human MCF-7 and SKBR3 cells exposed to different stressful situations. In untreated conditions MCF-7 and SKBR3 cells showed very different ß-catenin localization. In MCF-7 cells, cadmium administration caused a striking change in ß-catenin localization driving it from plasma membrane to cytoplasmic and perinuclear areas and HER2 showed a similar localization patterns. The changes induced by cadmium were compared with heat shock, H2O2 and tamoxifen treatments. In conclusion, this study shows the dynamical associations of HER2 and ß-catenin and their changes in subcellular localizations driven by stressful situations. In addition, we report for the first time the correlation between plasma membrane associated ß-catenin in HER2-positive breast cancer and survival outcome, and the importance of the protein localization in breast cancer samples.

Accuracy of fibular sectioning and insertion into a rapid-prototyped bone plate, for mandibular reconstruction using CAD-CAM technology.

Modern techniques of mandibular reconstruction, such as CAD-CAM technology and rapid prototyping, offer new means by which reconstructive surgery can be planned to optimise aesthetic outcomes and prosthetic rehabilitation. The high degree of accuracy afforded by these approaches is principally attributable to high-precision fibular sectioning and insertion of the bone into a customised bone plate. CAD-CAM mandibular reconstruction procedures using vascularised bone free-flap transfers were performed on 10 patients with benign or malignant neoplasms. Five were not treated with the aid of CAD-CAM technology, and served as the control group. Five were scheduled for maxillofacial surgery using surgical cutting guides and customised bone plates. A generalised linear model for linear measures was used to compare the accuracy of reconstruction between the two groups. A difference, even though not significant, in the lateral shift of the mesial and distal positions of the fibular units was evident between groups. CAD-CAM-generated fibular surgical guides afford improved accuracy when used to restore native anatomy, especially in the context of mandibular arch restoration, and both operating room time and related costs are reduced during fibular sectioning.

Technical aspects of prosthetically guided maxillofacial surgery of the mandible. A pilot test study.

A test of the accuracy in transferring the virtual data into the surgical environment was carried out. Differences between the virtually planned and the actual position during surgery of the rapid prototyped guides and the bone plates were investigated. The accuracy of the method was evaluated in terms of the precision of cuts in the mandible, the final positions of the rami and condyles, and the sectioning precision of the fibula. The guide position presented a mean value dislocation of 0.6 mm in the right side and of 4.1 mm in the left side; the cut line of the mandible presented an angular deviation of 2.9° (right) and of 17.5° (left). The right condyle was positioned 2.5 ± 0.05 mm more medial than native position, and the left condyle 5.2 ± 0.05 mm medial. The total length was 0.3 ± 0.05 mm short of the virtually projected length at the inferior margin of the mandible and 1.9 ± 0.05 mm longer than projected at the superior margin. The Prosthetically Guided Maxillofacial Surgery (PGMS) is a viable way to improve the precision of mandibular reconstruction using a fibula free flap.

The CAD-CAM technique for mandibular reconstruction: an 18 patients oncological case-series.

BACKGROUND: Modern techniques for mandibular reconstruction, such as CAD-CAM, offer new solutions for planning of reconstructive surgery in relation to the aesthetic outcome and the prosthetic rehabilitation. METHODS: CAD-CAM reconstruction procedures using vascularised bone free-flap transfers and surgical guides to cut the mandible and fibula were performed in 18 cases of neoplasms. The planned surgery was used to design and manufacture customised surgical devices. RESULTS: The mean follow-up was 12 months. All patients, except one, are alive without disease at the time of writing. Reconstructive microvascular flap survival was 100%. No major or minor microvascular complication occurred. No donor site complication was observed. CONCLUSIONS: CAD-CAM technology is a very useful way to obtain the native morphology of the mandible, especially when both bi-dimensional and tri-dimensional defects occur. The reconstruction protocol presented offers several benefits and few disadvantages, which are discussed in the article.

Oculo-facial rehabilitation after facial cancer removal: updated CAD/CAM procedures: a pilot study.

BACKGROUND AND AIM: Leaving open or closing the oculo-facial defect by means of a myocutaneous flap mainly depends on maxillofacial surgical considerations. For those cases that present a closed defect, the authors aim to evaluate an innovative method of ocular bulb positioning using a magnetic resonance imaging dataset. TECHNIQUE: Following cancer removal and plastic reconstructive surgery, a Digital Imaging and Communications in Medicine format magnetic resonance imaging dataset was used to determine the volume and position of the left ocular bulb. The exact location of the prosthetic bulb was determined by mirroring this position on the affected side. Images of the eyeglasses were imported into the virtual environment, and the designs of the substructure and facial prosthesis were projected using computer-aided design/computer-aided manufacture (CAD/CAM) technology. DISCUSSION: The updated method presented here enables restoration with a facial prosthesis, even when a myocutaneous flap is used to close the defect, thereby resolving the problem of ocular bulb positioning and enabling the rapid and easy design of a retention system connected to eyeglasses. CLINICAL RELEVANCE: The proposed protocol aims to develop and describe a viable method for the construction of a facial prosthesis for a patient whose face had been reconstructed using a myocutaneous free flap.

Prosthetically guided maxillofacial surgery: evaluation of the accuracy of a surgical guide and custom-made bone plate in oncology patients after mandibular reconstruction.

BACKGROUND: The aim of the present study was to evaluate the accuracy of prosthetically guided maxillofacial surgery in reconstructing the mandible with a free vascularized flap using custom-made bone plates and a surgical guide to cut the mandible and fibula. METHODS: The surgical protocol was applied in a study group of seven consecutive mandibular-reconstructed patients who were compared with a control group treated using the standard preplating technique on stereolithographic models (indirect computer-aided design/computer-aided manufacturing method). The precision of both surgical techniques (prosthetically guided maxillofacial surgery and indirect computer-aided design/computer-aided manufacturing procedure) was evaluated by comparing preoperative and postoperative computed tomographic data and assessment of specific landmarks. RESULTS: With regard to midline deviation, no significant difference was documented between the test and control groups. With regard to mandibular angle shift, only one left angle shift on the lateral plane showed a statistically significant difference between the groups. With regard to angular deviation of the body axis, the data showed a significant difference in the arch deviation. All patients in the control group registered greater than 8 degrees of deviation, determining a facial contracture of the external profile at the lower margin of the mandible. With regard to condylar position, the postoperative condylar position was better in the test group than in the control group, although no significant difference was detected. CONCLUSIONS: The new protocol for mandibular reconstruction using computer-aided design/computer-aided manufacturing prosthetically guided maxillofacial surgery to construct custom-made guides and plates may represent a viable method of reproducing the patient's anatomical contour, giving the surgeon better procedural control and reducing procedure time. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.