Correction to: Patient-Specific Mandibular Reconstruction Plates Increase Accuracy and Long-Term Stability in Immediate Alloplastic Reconstruction of Segmental Mandibular Defects.

[This corrects the article DOI: 10.1007/s12663-019-01323-9.].

Reduction in perioperative blood loss using ultrasound-activated scissors during tumour surgery.

The aim of this study was to compare the effectiveness of Harmonic Focus+ scissors with the conventional surgical method regarding surgical blood loss and transfusion of blood products in the surgical treatment of head and neck tumours. In a retrospective study, the intraoperative blood loss, number of units of transfusion products given, operating time, and inpatient length of stay of 74 patients with squamous cell carcinoma were compared. Patients who underwent classic tumour surgery were compared with a group treated with Harmonic Focus+ scissors. A significantly lower intraoperative blood loss (496.15⬰ml vs 1096.0⬰ml, respectively; P⬰=⬰0.002) and shorter operation time (436.89 minutes vs 493.13 minutes, respectively; P⬰=⬰0.030) were achieved using the Harmonic Focus+ scissors when compared to the classic tumour surgery. Additionally, fewer units of blood products needed to be transfused (administration of red cell concentrates, P⬰<⬰0.001) and the length of stay in the intensive care unit was shorter for patients treated with the Harmonic Focus+ scissors (P⬰=⬰0.009). The study results indicate that the use of Harmonic Focus+ scissors during surgery for cancer of the oral cavity and pharynx is a safe and cost-effective method. This is of paramount importance during a pandemic when medical resources are scarce, including access to blood reserves.

Intraoperative real-time navigation and intraoperative three-dimensional imaging for patient-specific total temporomandibular joint replacement.

Customized solutions for replacement of the temporomandibular joint (TMJ) along with surgical guides enable precise and fast transfer of the virtual plan to the patient. However, these guides lack information on screw vectors and length, and well-defined borders for bony resections towards the medial skull base. This retrospective study was performed to investigate the feasibility and benefit of real-time navigation and intraoperative three-dimensional imaging during total TMJ replacement (TJR), as well as patient clinical outcomes. Between 2016 and 2020, 26 customized prostheses were implanted in 21 patients either with or without real-time navigation and instrument tracking. The clinical, surgical, radiological, and navigational data were analysed. The accuracy of navigation registration with instrument tracking, precision of screw insertion, and implant and screw positions were analysed by fusion of the virtual plan and surgical outcome. Real-time navigation aided orientation during lateral skull base dissection and resection. However, the results of real-time navigation-aided drilling were inconclusive regarding vector and length control. At a mean 15.3±3.0 months of follow-up, average mouth opening had improved from 21.69±2.80mm to 36.40±1.25mm; the average pain score decreased from 6.18±0.74 to 1.06±0.52. Thus, intraoperative real-time navigation for TJR assists lateral skull base dissection and resection.

Patient-Specific Mandibular Reconstruction Plates Increase Accuracy and Long-Term Stability in Immediate Alloplastic Reconstruction of Segmental Mandibular Defects.

OBJECTIVES: The aim of the current study was to evaluate potential differences in the accuracy of mandibular reconstruction and long-term stability, with respect to different reconstructive procedures. METHODS: In total, 42 patients who had undergone primary segmental mandibular resection with immediate alloplastic reconstruction, with either manually pre-bent or patient-specific mandibular reconstruction plates (PSMRP), were included in this study. Mandibular dimensions, in terms of six clinically relevant distances (capitulum [most lateral points], capitulum [most medial points], incisura [most caudal points], mandibular foramina, coronoid process [most cranial points], dorsal tip of the mandible closest to the gonion point) determined from tomographic images, were compared prior to, and after surgery. RESULTS: Dimensional alterations were significantly more often found when conventionally bent titanium reconstruction plates were used. These occurred in the area of the coronoid process (p = 0.014). Plate fractures were significantly (p = 0.022) more often found within the manually pre-bent group than within the PSMRP group (17%/0%). CONCLUSION: The results suggest that the use of PSMRP may prevent rotation of the proximal mandibular segment, thus avoiding functional impairment. In addition, the use of PSMRP may potentially enhance the long-term stability of alloplastic reconstructions.

In vivo tissue engineered bone versus autologous bone: stability and structure.

This pilot study investigated the biomechanical properties of prefabricated, vascularized bioartificial bone grafts, which may provide an alternative bone source for the restoration of segmental osseous defects. Vascularized bioartificial bone grafts comprise an artificial customized scaffold made of beta-tricalcium phosphate. Bone formation along the prefabricated scaffold is induced by autogenous cancellous bone. Vascularization of the bone graft is provided by the host's vascular system. Within 6 months, a mammalian bioreactor (sheep were used in the present study) creates heterotopic vascularized bioartificial bone grafts of a predetermined anatomical shape, which can be harvested for reconstructing osseous defects. The bioartificial bone grafts in this study contained up to 25% bone tissue, as shown by histomorphometric analysis and computed tomography. Moreover, unconfined compression tests revealed that the constructs had mechanical characteristics similar to those of ovine cancellous bone. Therefore, this method could be applied to generate vascularized prefabricated bone substitutes for critical-size defects.