Locking plates nowadays represent an important treatment in bone trauma and bone healing due to its strong biomechanical properties. The purpose of this study was to both computationally and ...experimentally validate a novel screw locking system by comparing it to another locking system from state-of-the-art and to apply it in an environment of a fractured mandible. FEA was used to test both systems prior to experimental tests. The systems were locked in the plate holes at 0°, 10°, 15°, and 20°. Cyclic bending tests and push-out tests were performed in order to determine the stiffness and push-out forces of both locking systems. Finally, newly designed locking system was implemented in mandibular angle fracture. Control locking system was biomechanically superior in push-out test, but with no greater significance. In contrast, the new locking system showed greater stiffness by 17.3% at the deflection angle of 20° in cyclic tests, with lower values for other deflection angles. Similar values were displayed in fractured mandible angle environment. Greater stiffness of the new locking system in cyclic loading tests, together with polyaxiallity of the new locking screw, could lead to easier application and improved biomechanical stability of the mandible angle fractures.
Graphical abstract
: The purpose of this study was to develop and evaluate a deep learning model capable of autonomously detecting and segmenting radiolucent lesions in the lower jaw by utilizing You Only Look Once ...(YOLO) v8.
: This study involved the analysis of 226 lesions present in panoramic radiographs captured between 2013 and 2023 at the Clinical Hospital Dubrava and the School of Dental Medicine, University of Zagreb. Panoramic radiographs included radiolucent lesions such as radicular cysts, ameloblastomas, odontogenic keratocysts (OKC), dentigerous cysts and residual cysts. To enhance the database, we applied techniques such as translation, scaling, rotation, horizontal flipping and mosaic effects. We have employed the deep neural network to tackle our detection and segmentation objectives. Also, to improve our model's generalization capabilities, we conducted five-fold cross-validation. The assessment of the model's performance was carried out through metrics like Intersection over Union (IoU), precision, recall and mean average precision (mAP)@50 and mAP@50-95.
: In the detection task, the precision, recall, mAP@50 and mAP@50-95 scores without augmentation were recorded at 91.8%, 57.1%, 75.8% and 47.3%, while, with augmentation, were 95.2%, 94.4%, 97.5% and 68.7%, respectively. Similarly, in the segmentation task, the precision, recall, mAP@50 and mAP@50-95 values achieved without augmentation were 76%, 75.5%, 75.1% and 48.3%, respectively. Augmentation techniques led to an improvement of these scores to 100%, 94.5%, 96.6% and 72.2%.
: Our study confirmed that the model developed using the advanced YOLOv8 has the remarkable capability to automatically detect and segment radiolucent lesions in the mandible. With its continual evolution and integration into various medical fields, the deep learning model holds the potential to revolutionize patient care.
Velopharyngeal insufficiency is a disorder where the soft palate directs the air through the nose. It is often present in patients with previous cleft or short palate, but also in many other ...conditions. Symptoms are primarily to be found in speech, with very distinct nasal sound. After clinical evaluation and nasal endoscopy, surgery is considered. Several surgical techniques are in use, with posterior pharyngeal flap pharyngoplasty being most widely used. This method leaves the base of the posterior pharyngeal flap attached to the posterior pharyngeal wall, with two lateral ports on each side of the flap. Permanent nasopharyngeal obstruction is a very challenging pathology for anesthesiologists in case of mandatory nasal intubation since it is a relative contraindication for nasal intubation. Patients with previous palatoplasty will regularly appear in our routine anesthetic practice, in all surgical segments. The high risk of damage to the flap with possible bleeding can put the anesthesiologist in a very unpleasant situation if not aware of the permanent effect of this surgery. During preanesthetic assessment, if there is information on a previous pharyngoplasty, one should consider alternative options for nasotracheal intubation. All nasal insertion procedures must be either avoided or carried out with great caution, under fiberoptic visual control.
Hyaline fibromatosis syndrome (HFS) is a rare autosomal recessive genetic disorder characterized by accumulation of hyalinized fibrous tissue with cutaneous, mucosal, osteoarticular, and systemic ...involvement. The condition is caused by a mutation of ANTXR2 gene that results in a faulty synthesis of a transmembrane protein which leads up to excessive deposition of hyaline material in extracellular space. The first signs may be present at birth or appear during infancy, and joint stiffness is the first, most common, symptom. Other manifestations include joint contractures, hyperpigmented macules over bony prominences of the joints, and gingival hypertrophy. The symptom that raises suspicion of HFS is present later, along with subcutaneous growths. The progression of the disease includes enteropathy with extensive protein loss, chronic diarrhea and frequent infections. We present a case of a five-year-old girl with severe gingival hypertrophy that caused difficulties in eating and speaking. To the best of our knowledge, this is also the first patient in Croatia with a confirmed ANTXR2 gene mutation described in the literature.
Intraoperative stabilisation of bony fragments with maxillo-mandibular fixation (MMF) is an essential step in the surgical treatment of mandibular fractures that are treated with open reduction and ...internal fixation (ORIF). The MMF can be performed with or without wire-based methods, rigid or manual MMF, respectively. The aim of this study was to compare the use of manual versus rigid MMF, in terms of occlusal outcomes and infective complications.
This multi-centric prospective study involved 12 European maxillofacial centres and included adult patients (age ≥16 years) with mandibular fractures treated with ORIF. The following data were collected: age, gender, pre-trauma dental status (dentate or partially dentate), cause of injury, fracture site, associated facial fractures, surgical approach, modality of intraoperative MMF (manual or rigid), outcome (minor/major malocclusions and infective complications) and revision surgeries. The main outcome was malocclusion at 6 weeks after surgery.
Between May 1, 2021 and April 30, 2022, 319 patients-257 males and 62 females (median age, 28 years)-with mandibular fractures (185 single, 116 double and 18 triple fractures) were hospitalised and treated with ORIF. Intraoperative MMF was performed manually on 112 (35%) patients and with rigid MMF on 207 (65%) patients. The study variables did not differ significantly between the two groups, except for age. Minor occlusion disturbances were observed in 4 (3.6%) patients in the manual MMF group and in 10 (4.8%) patients in the rigid MMF group (p > .05). In the rigid MMF group, only one case of major malocclusion required a revision surgery. Infective complications involved 3.6% and 5.8% of patients in the manual and rigid MMF group, respectively (p > .05).
Intraoperative MMF was performed manually in nearly one third of the patients, with wide variability among the centres and no difference observed in terms of number, site and displacement of fractures. No significant difference was found in terms of postoperative malocclusion among patients treated with manual or rigid MMF. This suggests that both techniques were equally effective in providing intraoperative MMF.
Ameloblastic carcinoma (AC) is a rare and aggressive malignant epithelial odontogenic tumor, most commonly located in the mandible or maxilla. An extremely rare extragnathic localization of AC with ...no connection to the jaws, ectopic ameloblastic carcinoma (EAC), has so far been described only three times. This report presents a 64-year-old male with skull base ameloblastic carcinoma and offers a review of diagnostic and treatment challenges related to EAC. Because of its rarity and histological similarity to other tumors, EAC is often misdiagnosed. This is why we established a pathohistological and immunohistochemical profile of EAC that differentiates it from histologically similar tumors. The most frequently used EAC treatment is radical surgical resection, but the majority of reviewed reports described local recurrence. Taking into consideration new scientific discoveries on the molecular pathogenesis of ameloblastoma, we are the first to have performed BRAF mutation analysis in an EAC patient. BRAF inhibitors offer promising results in the treatment of BRAF-positive ameloblastomas and should continue to be researched in AC and EAC patients. Finally, EAC should be considered in differential diagnosis of head and neck tumors outside the jaws.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The training and preferences of surgeons influence the type of surgical treatment for mandibular fractures. This multicentre prospective study analyzed the current treatment strategies and outcomes ...for mandibular fractures with open reduction and internal fixation (ORIF).
This prospective study included patients aged ≥16 years who underwent ORIF for mandibular fractures in 12 European maxillofacial centers. Age, sex, pretrauma dental status, fracture cause, site and type, associated facial fractures, surgical approach, plate number and thickness (≤1.4 or ≥1.5 mm), duration of postoperative maxillomandibular fixation, occlusal and infective complications at 6 weeks and 3 months, and revision surgeries were recorded.
Between May 1, 2021 and April 30, 2022, 425 patients (194 single, 182 double, and 49 triple mandibular fractures) underwent ORIF for 1 or more fractures. Rigid osteosynthesis was performed for 74% of fractures and was significantly associated with displaced ( P =0.01) and comminuted ( P =0.03) fractures and with the number of nonsurgically treated fracture sites ( P =0.002). The angle was the only site associated with nonrigid osteosynthesis ( P <0.001). Malocclusions (5.6%) and infective complications (5.4%) were not associated with osteosynthesis type.
Rigid osteosynthesis was the most frequently performed treatment at all fracture sites, except the mandibular angle, and was significantly associated with displaced and comminuted fractures and the number of nonsurgically treated fracture sites. No significant differences were observed regarding postoperative malocclusion or infections among osteosynthesis types.
BACKGROUNDMidface reconstruction is one of the most challenging tasks for the reconstructive surgeon. We present a technique for the reconstruction of the midface after total maxillectomy with ...preservation of orbital contents.
METHODSSkeletal reconstruction is achieved with a preoperatively bent titanium sheet mesh on a universal skeletal model. The alveolar ridge, the anterior wall of the maxillary sinus, the zygomatic prominence, the lower orbital rim, and the orbital floor are reconstructed with a titanium mesh. A soft tissue free flap, preferably anterolateral thigh free flap, is harvested as well. A part of the flap is deepithelized and put in front of the mesh to prevent exposure, and the other part is used for palatal reconstruction.
RESULTSFour male and 1 female patients were reconstructed with titanium mesh. Four free flaps were raised3 anterolateral thigh and 1 latissimus dorsi. All free flaps survived. All patients received postoperative irradiation with 64 Gy. Median follow-up was 12 months; no major complications occurred. Mesh was exposed in only 1 case, which was managed successfully with resuspension of the heavy latissimus dorsi myocutaneous flap. Midface projection and height, globe position, ocular movements, and vision where satisfactory in all cases.
CONCLUSIONSMidface reconstruction with titanium mesh and soft tissue free flap is a reliable and safe method for functional and aesthetic reconstruction after maxillectomy.
To evaluate the relationship between soft tissue and bone structure for Class III patients before and after bilateral sagittal split osteotomy (BSSO) and bimaxillary orthognathic surgery; to ...determine the impact of other factors on soft tissue change; and to evaluate correlations between thickness of tissue before surgery, SNA, SNB, and ANB angles, and soft tissue changes.
The study included 78 Class III patients treated only with BSSO or with BSSO and Le Fort I osteotomy. Lateral cephalograms were taken before and 3 months to 1 year after surgery. After all points of the Zagreb82 and Legan and Burstone profile analysis were traced, the ratio of five soft tissue points before and after surgery was evaluated.
Soft tissue between points Sn and A and upper lip showed statistically significant changes for patients treated with bimaxillary surgery and BSSO. Only gender had an influence on soft tissue change. The correlation between soft tissue thickness and changes after surgery was significant. A change in SNB angle correlated with upper lip thickness for patients treated with BSSO but not for patients treated with BSSO and Le Fort I. SNA angle changes correlated with soft tissue changes between points Sn and A.
Results of this study show soft tissue changes after BSSO and BSSO and Le Fort I and eliminate the deficiencies that were indicated in the meta-analysis of soft tissue changes from a previous study.
The goal of mandibular fracture treatment is to restore static and dynamic occlusal functions. Open reduction and internal fixation (ORIF) of these fractures can be associated with an intraoperative ...and/or postoperative maxillo-mandibular fixation (MMF). The aim of this study was to analyse the use of perioperative MMF and its effects on occlusal outcomes in the management of mandibular fractures.
This multicentric prospective study included adult patients with mandibular fractures treated with ORIF. The following data were collected: age, gender, pre-trauma dental status (dentate, partially dentate), cause of injury, fracture site, associated facial fractures, surgical approach, type of ORIF (rigid, non-rigid or mixed), thickness and number of plates, modality of intraoperative MMF (arch bars, self-tapping and self-drilling screws STSDSs, manual, other) and duration of postoperative MMF. The primary outcome was malocclusion at 6 weeks and 3 months. Statistical analyses were performed with Fisher's exact test or chi-square test, as appropriate.
Between 1 May 2021 and 30 April 2022, 336 patients, 264 males and 72 females (median age, 28 years) with mandibular fractures (194 single, 124 double and 18 triple fractures) were hospitalized. Intraoperative MMF was performed in all patients. Osteosynthesis was rigid in 75% of single fractures, and rigid or mixed in 85% and 100% of double and triple fractures, respectively. Excluding patients who underwent manual reduction, postoperative MMF (median duration, 3 weeks) was performed in 140 (64%) patients, without differences by type or number of fractures (p > 0.05). No significant difference was found in the incidence of malocclusion in patients with postoperative MMF (5%, 95% confidence interval CI, 2–10%) compared to those without (4%; 95% IC, 1–11%) (p > 0.05).
Postoperative MMF was performed in more than half of the patients despite adequate fracture osteosynthesis, with wide variability amongst centers. No evidence of a reduction in the incidence of postoperative malocclusion in patients treated with postoperative MMF was found.
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